//! What stage 1c is checked with.
//!
//! `docs/FEATURE-MERMAID-RENDERER.md` §6 sets the terms, because konoma has twice been fooled by
//! a green suite that was measuring nothing (a diff harness that had quietly become a
//! self-comparison; a golden that pinned a function production did not call). So the tests here
//! are built around three questions that konoma cannot answer by itself:
//!
//! 1. **Does resvg draw the text at the width konoma measured?** [`box_width_matches_resvg`] puts
//! the emitted SVG through usvg with konoma's own font database and compares the box konoma
//! sized against `Text::bounding_box().width()`. That is konoma versus *resvg's real shaper*,
//! so it cannot decay into konoma versus konoma.
//! 2. **Is the geometry sound?** The `invariant_*` tests state the five properties §6 lists —
//! boxes do not overlap, edges do not cross a box's inside, a label sits on its own line and on
//! no box, an arrow tip lands on the target's boundary, the viewBox holds everything — over a
//! corpus built from the *specification's* cases (`§2-2`'s shapes, strokes, directions), not
//! from a list of bugs already found.
//! 3. **Does it still come out the same?** The golden is the SVG text (never a PNG: §6 notes
//! resvg 0.48 swapped its whole text stack), and it goes through [`super::render`], the
//! function production will call.
//!
//! # Why the golden masks its numbers
//!
//! Every coordinate in a diagram descends from a label width, and a label width comes from the
//! system's sans-serif face — Helvetica here, DejaVu Sans on the Linux CI box. A byte-exact
//! end-to-end golden would therefore be a golden of *this machine's fonts*, and would fail on CI
//! for a reason that has nothing to do with the renderer. So the corpus golden masks numeric
//! attribute values and pins everything else: which elements are emitted, in what order, with
//! which colours, which path commands, and which text. The numbers are pinned separately, by
//! [`emit_golden`] (which builds a diagram by hand, so no font is involved) and by the arithmetic
//! tests over the shape formulas.
//!
//! That the mask really is font-independent was measured rather than assumed: multiplying every
//! measured label width by 0.5, 0.85, 1.15, 1.3 and 2.0 — far past the gap between Helvetica and
//! DejaVu Sans — leaves `mermaid_render.snap` byte-identical. Ranks, orders and dummy-node counts
//! come from the graph's shape, not from its labels' widths, so the emitted element sequence does
//! not move with the font.
use std::collections::{HashMap, HashSet};
use std::path::{Path as FsPath, PathBuf};
use resvg::usvg;
use super::clusters;
use super::edges;
use super::labels::Label;
use super::shapes::{self, Glyph, Size};
use super::svg::num;
use super::theme::{self, Theme};
use super::{
lay_out, lay_out_curve, lay_out_flow, orthogonal, render, render_curve, render_flow, Curve,
Diagram, PlacedCluster, PlacedEdge, PlacedEdgeLabel, PlacedNode, RenderError, Routing, Tip,
MARGIN,
};
use crate::preview::mermaid::flowchart::{parse, Arrow, Direction, Shape, Stroke};
use crate::preview::mermaid::layout::Point;
use crate::preview::mermaid::text_metrics;
use crate::preview::svg::shared_fontdb;
// ---------------------------------------------------------------------------------------------
// Corpus
// ---------------------------------------------------------------------------------------------
/// The diagrams every structural test runs over.
///
/// Chosen from the *cases in the specification* rather than from past bugs (memory
/// `corpus-from-spec-not-from-bugs`): each of §2-2's classic shapes, each stroke and arrow
/// spelling, both label notations, all four directions, multi-line labels, CJK, a long edge that
/// skips ranks, a cycle, a self-loop, and a subgraph — which stage 1c must survive without
/// drawing (§7).
pub(super) const CORPUS: &[(&str, &str)] = &[
(
"branch",
"flowchart TD\n A[Start] --> B{Ready?}\n B -->|yes| C([Ship])\n B -->|no| D[Fix it]\n D --> B",
),
(
"shapes",
"flowchart TD\n a[rect] --> b(round)\n b --> c([stadium])\n c --> d[[sub]]\n \
d --> e[(store)]\n e --> f((circle))\n f --> g{diamond}\n g --> h{{hex}}\n \
h --> i>odd]\n i --> j[/lean/]\n j --> k[\\lean back\\]\n k --> l[/trap\\]\n \
l --> m[\\inv trap/]",
),
(
"strokes",
"flowchart LR\n A --- B\n B -.-> C\n C ==> D\n D --o E\n E --x F\n A <--> F\n \
C ~~~ E",
),
(
"cjk",
"flowchart TD\n A[ツリー] -->|Enter| B{種別を解決}\n B -->|画像| C[全画面プレビュー]\n \
B -->|テキスト| D[窓読み]\n D --> A",
),
(
"long-edge",
"flowchart TD\n A --> B --> C --> D --> E\n A --> E\n E --> B\n C --> A",
),
(
"left-right",
"flowchart LR\n Parse -- tokens --> Layout -- boxes --> Draw\n Draw --> Parse",
),
(
"bottom-top",
"flowchart BT\n leaf1 --> mid\n leaf2 --> mid\n mid --> root",
),
(
"right-left",
"flowchart RL\n A[one] --> B[two]\n B --> C[three]",
),
(
"multiline",
"flowchart TD\n A[first line<br>second line<br>third] --> B[\"one\\ntwo\"]",
),
(
"self-loop",
"flowchart TD\n A[retry] --> A\n A --> B[done]",
),
(
"subgraph",
"flowchart TD\n subgraph one [Group]\n A --> B\n end\n B --> C\n C --> A",
),
(
"subgraph-nested",
"flowchart TD\n subgraph outer [Outer]\n subgraph inner [Inner]\n A --> B\n end\n B --> C\n end\n C --> D",
),
(
"subgraph-siblings",
"flowchart LR\n subgraph left [Read]\n A --> B\n end\n subgraph right [Write]\n C --> D\n end\n B --> C",
),
(
// A block sitting between two nodes that have nothing to do with it: `X --> Y` spans the
// same ranks the frame does, and it is dagre's compound layout (`parentDummyChains`) that
// keeps its waypoints out of the box rather than anything this renderer does afterwards.
"subgraph-bypass",
"flowchart LR\n subgraph one [Middle]\n A --> B\n end\n X --> Y\n X --> A\n B --> Y",
),
(
"subgraph-endpoint",
"flowchart LR\n subgraph one [First]\n A --> B\n end\n subgraph two [Second]\n C --> D\n end\n one --> two\n E --> one",
),
(
"subgraph-direction",
"flowchart LR\n subgraph one [Steps]\n direction TB\n A --> B --> C\n end\n one --> D",
),
(
"subgraph-cjk",
"flowchart TD\n subgraph proc [プレビュー解決]\n A[種別] --> B[レンダラ]\n end\n B --> C[全画面表示]",
),
(
"subgraph-long-title",
"flowchart TD\n subgraph one [resolve the preview kind and delegate it]\n A --> B\n end\n subgraph two [b]\n C --> D\n end\n B --> C",
),
(
// A two-line title is the case that makes a frame grow upward: the band dagre leaves
// above the topmost rank is one `ranksep`/2, which fits one line of text and not two.
"subgraph-tall-title",
"flowchart TD\n subgraph one [Resolve the kind<br>and delegate]\n A --> B\n end\n B --> C",
),
(
"subgraph-untitled",
"flowchart TD\n subgraph\n A --> B\n end\n B --> C",
),
(
"amp-chain",
"flowchart LR\n A & B --> C & D\n C --> E",
),
(
"length",
"flowchart TD\n A ---> B\n A --> C\n B --> D\n C --> D",
),
(
// `linkStyle` naming several indices at once, in the exact shape a real diagram uses it
// (`~/work/Ergora/doc/spec/05-system-architecture.md`'s six colour-coded groups of edges
// — the source of the 2026-08-28 regression `docs/STATUS.md` records). Before that fix,
// `mask_numbers` would have shown this case's colour drift — `fill`/`stroke` are two of
// the few attributes it does *not* mask — but no corpus case exercised `linkStyle` at
// all, which is exactly how the regression reached a release unnoticed.
"link-style-multi-index",
"flowchart TD\n A --> B\n B --> C\n C --> D\n D --> E\n \
linkStyle 0,1,2 stroke:#1f6feb\n linkStyle 3 stroke:#d4a017",
),
(
// `classDef` + `:::` + a node's own `style` together, so the golden pins the whole
// cascade at once: `default` colours every node, `:::hot` overrides the one it names, and
// `style` on top of that overrides `:::hot` again.
"classdef-and-style-cascade",
"flowchart TD\n classDef default fill:#223,stroke:#556\n \
classDef hot fill:#f9f,stroke:#a00\n A:::hot --> B\n style A fill:#0f0",
),
];
/// Label strings the measuring instrument runs over. §6 names these classes explicitly: CJK,
/// emoji, text with kerning pairs, thin glyphs, long runs and mixtures.
const LABELS: &[(&str, &str)] = &[
("ascii", "Start"),
("kerning", "AVATAR To Wa"),
("thin", "illicit lilli"),
("cjk", "全画面プレビュー"),
("cjk-punct", "開始、処理。「確認」"),
("emoji", "build 🚀 ship"),
(
"long",
"resolve the preview kind and hand it to the right renderer",
),
(
"mixed",
"konoma のプレビュー preview を全画面 fullscreen で",
),
("digits", "0123456789"),
("one", "x"),
// usvg folds runs of whitespace *before* it shapes, so a label written with two spaces is
// drawn one space narrower than its bytes suggest. Measuring the bytes sizes a box the text
// does not fill, and every coordinate downstream of that box moves with it. Stage 4 met this
// for real on a sequence diagram's `loop Every minute`; `docs/STATUS.md` recorded it as a
// hole in every kind's measurement, so each kind's instrument now carries a case of it.
("double-space", "loop Every minute"),
("edge-space", " padded out "),
];
// ---------------------------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------------------------
fn laid_out(src: &str) -> Diagram {
let chart = parse(src).unwrap_or_else(|e| panic!("corpus source must parse: {e}"));
lay_out(&chart).unwrap_or_else(|e| panic!("corpus source must lay out: {e}"))
}
/// [`laid_out`], with every edge's curve resolved from `curve` (`ui.mermaid_curve`'s raw
/// string) the way [`lay_out_curve`] resolves it.
fn laid_out_curve(src: &str, curve: &str) -> Diagram {
let chart = parse(src).unwrap_or_else(|e| panic!("corpus source must parse: {e}"));
lay_out_curve(&chart, curve).unwrap_or_else(|e| panic!("corpus source must lay out: {e}"))
}
/// [`laid_out_curve`], with edges additionally routed by `routing` (`ui.mermaid_routing`'s raw
/// string) the way [`lay_out_flow`] resolves it.
pub(super) fn laid_out_flow(src: &str, curve: &str, routing: &str) -> Diagram {
let chart = parse(src).unwrap_or_else(|e| panic!("corpus source must parse: {e}"));
lay_out_flow(&chart, curve, routing)
.unwrap_or_else(|e| panic!("corpus source must lay out: {e}"))
}
/// A [`PlacedNode`] with a plain rectangle glyph and a blank label — a hand-built layout input for
/// the stage 2-4 unit tests below, the same role `orthogonal.rs`'s own private `node` helper plays
/// for that module's tests (kept separate rather than shared: the two test modules build different
/// things from a node — this file also needs a full [`GraphSpec`] elsewhere, which
/// `orthogonal.rs`'s helper has no reason to know about).
fn placed_node(id: &str, cx: f64, cy: f64, w: f64, h: f64) -> PlacedNode {
PlacedNode {
id: id.to_string(),
shape: Glyph::default(),
center: Point::new(cx, cy),
size: Size::new(w, h),
label: Label::measure(""),
panel: None,
series: None,
mark: None,
style: None,
}
}
pub(super) fn tree_of(svg: &str) -> usvg::Tree {
let opt = usvg::Options {
fontdb: shared_fontdb(),
..usvg::Options::default()
};
usvg::Tree::from_data(svg.as_bytes(), &opt).expect("emitted SVG parses")
}
/// Every `<text>` in the tree, as the width resvg actually laid it out at.
pub(super) fn text_widths(group: &usvg::Group, out: &mut Vec<f32>) {
for node in group.children() {
match node {
usvg::Node::Text(t) => out.push(t.bounding_box().width()),
usvg::Node::Group(g) => text_widths(g, out),
_ => {}
}
}
}
/// Every `<text>` in the tree, as the string it holds and the width resvg laid it out at.
///
/// The content is what makes an instrument precise: a document usually has several kinds of label
/// in it, and comparing the widest one would only ever measure the widest kind.
pub(super) fn measured_texts(group: &usvg::Group, out: &mut Vec<(String, f64)>) {
for node in group.children() {
match node {
usvg::Node::Text(t) => {
let s: String = t.chunks().iter().map(|c| c.text().to_string()).collect();
out.push((s, t.bounding_box().width() as f64));
}
usvg::Node::Group(g) => measured_texts(g, out),
_ => {}
}
}
}
/// Every drawn path's bounding box (fill geometry, stroke excluded).
pub(super) fn path_boxes(group: &usvg::Group, out: &mut Vec<usvg::Rect>) {
for node in group.children() {
match node {
usvg::Node::Path(p) => out.push(p.bounding_box()),
usvg::Node::Group(g) => path_boxes(g, out),
_ => {}
}
}
}
/// Squared distance from `p` to the segment `a`-`b`.
pub(super) fn dist_to_segment(p: &Point, a: &Point, b: &Point) -> f64 {
let (dx, dy) = (b.x - a.x, b.y - a.y);
let len2 = dx * dx + dy * dy;
if len2 == 0.0 {
return (p.x - a.x).hypot(p.y - a.y);
}
let t = (((p.x - a.x) * dx + (p.y - a.y) * dy) / len2).clamp(0.0, 1.0);
(p.x - (a.x + t * dx)).hypot(p.y - (a.y + t * dy))
}
pub(super) fn dist_to_polyline(p: &Point, line: &[Point]) -> f64 {
line.windows(2)
.map(|w| dist_to_segment(p, &w[0], &w[1]))
.fold(f64::INFINITY, f64::min)
}
/// The boundary of a placed node, as a closed polygon in absolute coordinates.
///
/// Deliberately built from [`shapes::polygon`] and the bounding box rather than from
/// [`shapes::intersect`]: the invariant "the arrow tip is on the boundary" has to be checked
/// against the outline, not against the same function that produced the point.
pub(super) fn boundary(node: &PlacedNode) -> Vec<Point> {
let (w, h) = (node.size.w, node.size.h);
let (cx, cy) = (node.center.x, node.center.y);
let local = shapes::polygon(node.shape, node.size);
if !local.is_empty() {
return local
.into_iter()
.map(|p| Point::new(cx + p.x, cy + p.y))
.collect();
}
match node.shape {
// Sampled finely enough that "on the boundary" is decided by geometry, not by the sample
// count: 256 segments on a circle of radius 100 deviate by under 0.008px.
// Both `[*]` markers are circles too — a `stateEnd`'s ring is what an edge stops on, and
// measuring it against a bounding box instead lets a line end up to `r(1 - 1/√2)` inside
// the shape without the invariant noticing.
Glyph::Flow(Shape::Circle)
| Glyph::Flow(Shape::DoubleCircle)
| Glyph::StateStart
| Glyph::StateEnd => {
let r = w / 2.0;
(0..256)
.map(|i| {
let t = std::f64::consts::TAU * i as f64 / 256.0;
Point::new(cx + r * t.cos(), cy + r * t.sin())
})
.collect()
}
_ => vec![
Point::new(cx - w / 2.0, cy - h / 2.0),
Point::new(cx + w / 2.0, cy - h / 2.0),
Point::new(cx + w / 2.0, cy + h / 2.0),
Point::new(cx - w / 2.0, cy + h / 2.0),
],
}
}
/// [`shapes::size`] for one of a flowchart's own shapes, which is what the arithmetic tests are
/// written about. The renderer measures every node through [`Glyph`]; wrapping it here keeps the
/// formulas readable as formulas.
fn flow_size(shape: Shape, label: Size) -> Size {
shapes::size(Glyph::Flow(shape), label)
}
/// Distance from `p` to a closed polygon's boundary.
pub(super) fn dist_to_boundary(p: &Point, poly: &[Point]) -> f64 {
let n = poly.len();
(0..n)
.map(|i| dist_to_segment(p, &poly[i], &poly[(i + 1) % n]))
.fold(f64::INFINITY, f64::min)
}
/// Even-odd point-in-polygon.
pub(super) fn inside(p: &Point, poly: &[Point]) -> bool {
let n = poly.len();
let mut hit = false;
let mut j = n - 1;
for i in 0..n {
let (a, b) = (&poly[i], &poly[j]);
if (a.y > p.y) != (b.y > p.y) {
let x = a.x + (p.y - a.y) / (b.y - a.y) * (b.x - a.x);
if p.x < x {
hit = !hit;
}
}
j = i;
}
hit
}
/// How far inside the shape `p` lies, or 0 when it is outside.
pub(super) fn depth(p: &Point, poly: &[Point]) -> f64 {
if inside(p, poly) {
dist_to_boundary(p, poly)
} else {
0.0
}
}
/// The subgraph tree of a source, rebuilt from the parser's own output.
///
/// The cluster invariants need to know who is inside what, and the [`Diagram`] deliberately does
/// not carry membership — a frame is geometry. Re-deriving it from [`parse`] keeps the question
/// ("is this node a member of that block?") answered by the parser, which stage 1b tested, rather
/// than by the layout code under test here.
fn tree_of_src(src: &str) -> clusters::Tree {
let chart = parse(src).expect("parses");
let ids: HashSet<String> = chart.nodes.iter().map(|n| n.id.clone()).collect();
clusters::Tree::build(&chart, |id| ids.contains(id))
}
/// Axis-aligned overlap of two rectangles given as `(l, t, r, b)`.
pub(super) fn rect_overlap(a: (f64, f64, f64, f64), b: (f64, f64, f64, f64)) -> (f64, f64) {
(a.2.min(b.2) - a.0.max(b.0), a.3.min(b.3) - a.1.max(b.1))
}
/// How far `inner` pokes out of `outer`, as the worst of the four sides. Negative means contained.
pub(super) fn escapes(inner: (f64, f64, f64, f64), outer: (f64, f64, f64, f64)) -> f64 {
(outer.0 - inner.0)
.max(outer.1 - inner.1)
.max(inner.2 - outer.2)
.max(inner.3 - outer.3)
}
/// The deepest a polyline reaches inside a rectangle, sampling every half pixel. 0 when it never
/// enters. Sampling rather than testing the vertices is what catches a segment that cuts a corner.
pub(super) fn polyline_depth_in_rect(line: &[Point], rect: (f64, f64, f64, f64)) -> f64 {
let depth_at = |p: &Point| {
let d = (p.x - rect.0)
.min(rect.2 - p.x)
.min(p.y - rect.1)
.min(rect.3 - p.y);
d.max(0.0)
};
let mut worst: f64 = 0.0;
for w in line.windows(2) {
let len = (w[1].x - w[0].x).hypot(w[1].y - w[0].y);
let steps = (len / 0.5).ceil().max(1.0) as usize;
for i in 0..=steps {
let t = i as f64 / steps as f64;
let p = Point::new(
w[0].x + t * (w[1].x - w[0].x),
w[0].y + t * (w[1].y - w[0].y),
);
worst = worst.max(depth_at(&p));
}
}
worst
}
/// Axis-aligned overlap of two node boxes, as `(dx, dy)` — both positive means they intersect.
pub(super) fn box_overlap(a: &PlacedNode, b: &PlacedNode) -> (f64, f64) {
let (al, at, ar, ab) = a.bounds();
let (bl, bt, br, bb) = b.bounds();
(ar.min(br) - al.max(bl), ab.min(bb) - at.max(bt))
}
/// Masks the value of every numeric attribute, leaving structure, colours and text intact.
///
/// `M12.5,4 L20,4` becomes `M#,# L#,#`, so the golden pins which path commands are emitted in
/// which order without pinning coordinates that descend from the system font.
pub(super) fn mask_numbers(svg: &str) -> String {
const NUMERIC: &[&str] = &[
"x",
"y",
"x1",
"y1",
"x2",
"y2",
"width",
"height",
"rx",
"ry",
"cx",
"cy",
"r",
"d",
"points",
"stroke-width",
"dy",
"font-size",
"stroke-dasharray",
"viewBox",
];
let numeric: HashSet<&str> = NUMERIC.iter().copied().collect();
let mut out = String::with_capacity(svg.len());
let bytes: Vec<char> = svg.chars().collect();
let mut i = 0;
while i < bytes.len() {
// Find `name="` where `name` is a numeric attribute.
if bytes[i] == '=' && i + 1 < bytes.len() && bytes[i + 1] == '"' {
let mut start = i;
while start > 0 && (bytes[start - 1].is_ascii_alphanumeric() || bytes[start - 1] == '-')
{
start -= 1;
}
let name: String = bytes[start..i].iter().collect();
if numeric.contains(name.as_str()) {
out.push_str("=\"");
let mut j = i + 2;
let mut in_number = false;
while j < bytes.len() && bytes[j] != '"' {
let c = bytes[j];
if c.is_ascii_digit() || c == '.' || (c == '-' && !in_number) {
if !in_number {
out.push('#');
in_number = true;
}
} else {
in_number = false;
out.push(c);
}
j += 1;
}
out.push('"');
i = j + 1;
continue;
}
}
out.push(bytes[i]);
i += 1;
}
out
}
/// The columns of an emitted SVG that a routing regression would actually move: every `d` (a
/// path's shape, with its numbers masked the same way [`mask_numbers`] masks them — font-dependent
/// label widths must not make this signature drift between Helvetica here and DejaVu Sans on
/// Linux CI, the same reason `corpus_golden` masks numbers at all) and every literal `fill`/
/// `stroke` (colour, which `mask_numbers` never touches — see the `link-style-multi-index` corpus
/// comment for why that's deliberate). One attribute per line, document order preserved, so a
/// change in bend count, sign pattern, command letter, or colour still moves this string even
/// though the exact coordinates are masked away.
pub(super) fn routing_signature(svg: &str) -> String {
let masked = mask_numbers(svg);
let mut out = String::new();
let chars: Vec<char> = masked.chars().collect();
let mut i = 0;
while i < chars.len() {
if chars[i] == '=' && i + 1 < chars.len() && chars[i + 1] == '"' {
let mut start = i;
while start > 0 && (chars[start - 1].is_ascii_alphanumeric() || chars[start - 1] == '-')
{
start -= 1;
}
let name: String = chars[start..i].iter().collect();
if matches!(name.as_str(), "d" | "fill" | "stroke") {
let mut j = i + 2;
while j < chars.len() && chars[j] != '"' {
j += 1;
}
let value: String = chars[i + 2..j].iter().collect();
out.push_str(&name);
out.push('=');
out.push_str(&value);
out.push('\n');
i = j + 1;
continue;
}
}
i += 1;
}
out
}
pub(super) fn snapshot_path(name: &str) -> PathBuf {
FsPath::new(env!("CARGO_MANIFEST_DIR"))
.join("snapshots")
.join(format!("{name}.snap"))
}
/// Compares against the checked-in snapshot, following konoma's existing convention:
/// `KONOMA_UPDATE_SNAPSHOTS=1` rewrites the file, and a missing file skips (a build from the
/// published crate has no `snapshots/`, which is excluded).
pub(super) fn assert_snapshot(name: &str, actual: &str) {
let path = snapshot_path(name);
if std::env::var_os("KONOMA_UPDATE_SNAPSHOTS").is_some() {
std::fs::create_dir_all(path.parent().expect("snapshot dir")).expect("create snapshots/");
std::fs::write(&path, actual).expect("write snapshot");
eprintln!("mermaid snapshot: wrote {}", path.display());
return;
}
let Ok(expected) = std::fs::read_to_string(&path) else {
eprintln!(
"mermaid snapshot: {} not found — skipping (published-crate build?); \
regenerate with `KONOMA_UPDATE_SNAPSHOTS=1 cargo test`",
path.display()
);
return;
};
if expected == actual {
return;
}
let (el, al): (Vec<&str>, Vec<&str>) = (expected.lines().collect(), actual.lines().collect());
let mut i = 0;
while i < el.len().min(al.len()) && el[i] == al[i] {
i += 1;
}
let lo = i.saturating_sub(2);
panic!(
"mermaid snapshot {name} drifted at line {i}\n--- expected ---\n{}\n--- actual ---\n{}\n\
Re-run with KONOMA_UPDATE_SNAPSHOTS=1 and inspect the diff if this is intentional.",
el[lo..(i + 3).min(el.len())].join("\n"),
al[lo..(i + 3).min(al.len())].join("\n"),
);
}
// ---------------------------------------------------------------------------------------------
// 1. The main instrument: what konoma measured vs what resvg drew
// ---------------------------------------------------------------------------------------------
/// **The instrument §6 asks for.** A one-node diagram is emitted, put through usvg with konoma's
/// own font database, and the box konoma sized is compared against the width resvg laid the text
/// out at. The relation is exact and declared: a rectangle is the label plus `padding * 4`
/// (`squareRect.ts` doubles `padding` for `labelPaddingX`, `drawRect.ts` doubles it again).
///
/// This is konoma against **resvg's real shaper**, not against another copy of konoma, so it
/// cannot silently become a self-comparison — the failure mode that made the markdown diff
/// harness report "468/468 identical" while every paragraph was broken.
#[test]
fn box_width_matches_resvg() {
if !text_metrics::fonts_available() {
eprintln!("no sans-serif face — skipping (the renderer refuses to draw here too)");
return;
}
let expected_padding = shapes::PADDING * 4.0;
for (name, label) in LABELS {
let src = format!("flowchart TD\n A[\"{label}\"]");
let diagram = laid_out(&src);
let svg = render(&src, "dark").expect("renders");
let node = &diagram.nodes[0];
let mut widths = Vec::new();
text_widths(tree_of(&svg).root(), &mut widths);
assert_eq!(
widths.len(),
1,
"{name}: exactly one <text> should survive usvg (a dropped one means the font \
resolution konoma measured with is not the one resvg drew with)"
);
let drawn = widths[0] as f64;
let slack = node.size.w - drawn;
assert!(
(slack - expected_padding).abs() <= 1.0,
"{name} {label:?}: box is {} wide, resvg drew the text {} wide → {} of padding, \
but the shape declares {}",
num(node.size.w),
num(drawn),
num(slack),
num(expected_padding)
);
// …and the box konoma sized is the box it emitted.
let mut boxes = Vec::new();
path_boxes(tree_of(&svg).root(), &mut boxes);
assert!(
boxes
.iter()
.any(|b| (b.width() as f64 - node.size.w).abs() < 0.01 && b.x() > 0.0),
"{name}: no drawn path has the width the model declares ({})",
num(node.size.w)
);
}
}
/// The same comparison for an edge label, which is measured by the same code but sized by a
/// different rule (a small pad, not a shape's padding).
#[test]
fn edge_label_box_matches_resvg() {
if !text_metrics::fonts_available() {
return;
}
let src = "flowchart TD\n A[a] -->|全画面プレビュー| B[b]";
let diagram = laid_out(src);
let svg = render(src, "dark").expect("renders");
let label = diagram.edges[0]
.label
.as_ref()
.expect("edge carries a label");
let mut widths = Vec::new();
text_widths(tree_of(&svg).root(), &mut widths);
// Two node labels and the edge label; the edge label is the widest here.
let drawn = widths.iter().copied().fold(0.0_f32, f32::max) as f64;
let slack = label.size.w - drawn;
assert!(
(slack - super::LABEL_PAD_X * 2.0).abs() <= 1.0,
"edge label box {} vs resvg's {} → {} of padding, declared {}",
num(label.size.w),
num(drawn),
num(slack),
num(super::LABEL_PAD_X * 2.0)
);
}
/// A multi-line label is as tall as its line count says, and as wide as its widest line — which
/// is what makes `<br>` change a box's shape rather than just its text.
#[test]
fn multiline_label_is_measured_per_line() {
if !text_metrics::fonts_available() {
return;
}
let one = Label::measure("short");
let three = Label::measure("short\nconsiderably longer line\nmid");
assert_eq!(three.lines.len(), 3);
assert!((three.height - one.height * 3.0).abs() < 1e-9);
assert!(three.width > one.width);
assert!((three.width - Label::measure("considerably longer line").width).abs() < 1e-9);
}
// ---------------------------------------------------------------------------------------------
// 2. Geometric invariants (§6's supporting list)
// ---------------------------------------------------------------------------------------------
/// (1) No two node boxes overlap.
pub(super) fn check_nodes_do_not_overlap(name: &str, d: &Diagram) {
for i in 0..d.nodes.len() {
for j in (i + 1)..d.nodes.len() {
let (dx, dy) = box_overlap(&d.nodes[i], &d.nodes[j]);
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: {} and {} overlap by {}x{}",
d.nodes[i].id,
d.nodes[j].id,
num(dx),
num(dy)
);
}
}
}
#[test]
fn invariant_nodes_do_not_overlap() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_nodes_do_not_overlap(name, &laid_out(src));
}
}
/// (2) No edge passes through the inside of a shape.
///
/// Checked against each node's **outline**, not its bounding box: a diamond's box is far bigger
/// than the diamond, and an edge leaving one legitimately crosses the box's corner. Sampling the
/// polyline every half pixel and asking how deep inside each sample lies makes the check
/// independent of `shapes::intersect`, which is the function under test.
///
/// **An edge that names a block is exempt**, for the reason spelled out on
/// [`check_edges_keep_out_of_foreign_frames`] and recorded by
/// [`an_edge_that_names_a_block_is_not_kept_clear_of_its_surroundings`]: dagre was handed a
/// stand-in leaf instead of the endpoint the author wrote, and the line is only cut back to the
/// frame afterwards, so nothing constrained the route to clear the boxes beside it.
///
/// **A note's connector is exempt** for a different reason, recorded by
/// [`super::state_tests::a_notes_connector_can_cross_a_state_in_a_crowded_diagram`]: a note is
/// placed on the side the author named rather than where a clear line to it exists, and on a
/// crowded diagram those are not the same place. It is a straight line between two boxes, not a
/// route, so there is nothing here for the layout to have got wrong.
pub(super) fn check_edges_stay_out_of_shapes(name: &str, d: &Diagram) {
let outlines: Vec<Vec<Point>> = d.nodes.iter().map(boundary).collect();
for e in &d.edges {
// See the doc comment. A frame in this diagram bearing the endpoint's name is exactly
// "this edge was routed between stand-ins"; an end drawn as a note is exactly "this line
// was not routed at all".
if d.cluster(&e.from).is_some() || d.cluster(&e.to).is_some() {
continue;
}
let is_note = |id: &str| d.node(id).is_some_and(|n| n.shape == Glyph::Note);
if is_note(&e.from) || is_note(&e.to) {
continue;
}
let line = e.drawn_points();
for w in line.windows(2) {
let len = (w[1].x - w[0].x).hypot(w[1].y - w[0].y);
let steps = ((len * 2.0).ceil() as usize).clamp(1, 4000);
for s in 0..=steps {
let t = s as f64 / steps as f64;
let p = Point::new(
w[0].x + t * (w[1].x - w[0].x),
w[0].y + t * (w[1].y - w[0].y),
);
for (node, poly) in d.nodes.iter().zip(&outlines) {
let inside_by = depth(&p, poly);
assert!(
inside_by <= 1.0,
"{name}: edge {}->{} runs {}px inside {} at ({}, {})",
e.from,
e.to,
num(inside_by),
node.id,
num(p.x),
num(p.y)
);
}
}
}
}
}
#[test]
fn invariant_edges_stay_out_of_shapes() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_edges_stay_out_of_shapes(name, &laid_out(src));
}
}
/// (3) An edge label sits **on its own line** and on no node.
///
/// The first half is what distinguishes re-placing the label at the arc midpoint from leaving it
/// where dagre put it: dagre's position is offset from the line by `labeloffset` because its
/// default `labelpos` is `r`.
pub(super) fn check_labels_ride_their_edge(name: &str, d: &Diagram) {
for e in &d.edges {
let Some(label) = &e.label else { continue };
let off = dist_to_polyline(&label.center, &e.points);
assert!(
off <= 0.5,
"{name}: label {:?} on {}->{} sits {}px off its own line",
label.label.lines.join(" "),
e.from,
e.to,
num(off)
);
for n in &d.nodes {
let (nl, nt, nr, nb) = n.bounds();
let (ll, lt, lr, lb) = (
label.center.x - label.size.w / 2.0,
label.center.y - label.size.h / 2.0,
label.center.x + label.size.w / 2.0,
label.center.y + label.size.h / 2.0,
);
let (dx, dy) = (nr.min(lr) - nl.max(ll), nb.min(lb) - nt.max(lt));
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: label {:?} overlaps node {} by {}x{}",
label.label.lines.join(" "),
n.id,
num(dx),
num(dy)
);
}
}
}
#[test]
fn invariant_labels_ride_their_edge_and_clear_every_node() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_labels_ride_their_edge(name, &laid_out(src));
}
}
/// (4) Every edge starts and ends **on** the outline of the shape it touches.
///
/// This is the property that makes a branch come out of a diamond's slanted side. Comparing
/// against a densely sampled outline rather than against `shapes::intersect` keeps the check
/// honest: replacing the shape intersection with a bounding-box one has to fail here.
///
/// An end that names a *block* has no outline; it lands on a frame, which
/// [`invariant_an_edge_that_names_a_block_stops_on_its_frame`] checks instead.
pub(super) fn check_endpoints_land_on_the_outline(name: &str, d: &Diagram) {
for e in &d.edges {
let placed = |id: &str| match d.node(id) {
Some(n) => Some(n),
None if d.cluster(id).is_some() => None,
None => panic!(
"{name}: edge {}->{} names a node that is not placed",
e.from, e.to
),
};
let (tail, head) = (placed(&e.from), placed(&e.to));
let first = e.points.first().expect("edge has points");
let last = e.points.last().expect("edge has points");
for (label, p, node) in [("start", first, tail), ("end", last, head)]
.into_iter()
.filter_map(|(l, p, n)| n.map(|n| (l, p, n)))
{
let off = dist_to_boundary(p, &boundary(node));
assert!(
off <= 0.05,
"{name}: {label} of {}->{} is {}px off {}'s outline",
e.from,
e.to,
num(off),
node.id
);
}
}
}
#[test]
fn invariant_endpoints_land_on_the_outline() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_endpoints_land_on_the_outline(name, &laid_out(src));
}
}
/// (5) The viewBox contains every node, every waypoint and every label.
pub(super) fn check_view_box_contains_everything(name: &str, d: &Diagram) {
let check = |x: f64, y: f64, what: &str| {
assert!(
x >= -0.01 && y >= -0.01 && x <= d.width + 0.01 && y <= d.height + 0.01,
"{name}: {what} at ({}, {}) is outside the {}x{} viewBox",
num(x),
num(y),
num(d.width),
num(d.height)
);
};
for n in &d.nodes {
let (l, t, r, b) = n.bounds();
check(l, t, &n.id);
check(r, b, &n.id);
}
for e in &d.edges {
for p in e.drawn_points() {
check(p.x, p.y, "waypoint");
}
if let Some(l) = &e.label {
check(
l.center.x - l.size.w / 2.0,
l.center.y - l.size.h / 2.0,
"label",
);
check(
l.center.x + l.size.w / 2.0,
l.center.y + l.size.h / 2.0,
"label",
);
}
}
// …and the margin is really there.
let left = d
.nodes
.iter()
.map(|n| n.bounds().0)
.fold(f64::INFINITY, f64::min);
assert!(
left >= MARGIN - 0.01,
"{name}: drawing starts left of the margin"
);
}
#[test]
fn invariant_view_box_contains_everything() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_view_box_contains_everything(name, &laid_out(src));
}
}
// ---------------------------------------------------------------------------------------------
// 4b. Cluster invariants (§6, stage 1d)
// ---------------------------------------------------------------------------------------------
/// (6) A frame holds every one of its members.
///
/// This is the whole promise of a subgraph: the reader is being told that these nodes belong
/// together. A frame that clips a member says something false about the diagram.
pub(super) fn check_clusters_hold_their_members(name: &str, d: &Diagram, tree: &clusters::Tree) {
for c in &d.clusters {
let frame = c.bounds();
for n in &d.nodes {
if !tree.touches(&n.id, &c.id) {
continue;
}
let out = escapes(n.bounds(), frame);
assert!(
out <= 0.01,
"{name}: node {} pokes {out:.2}px out of frame {}",
n.id,
c.id
);
}
}
}
/// (6b) A frame holds none of what is *not* its member — the converse of (6), above.
///
/// §10-5 part-3 item 1's own invariant ("ノードは所属クラスターの枠内・非所属ノードは枠外"): a
/// node with no membership in a cluster (`clusters::Tree::touches` false) must not overlap that
/// cluster's own frame at all. Nothing before this checked the converse of (6) — every existing
/// cluster check only ever asked "does a member ever escape its own frame", never "does a
/// *stranger* ever land inside one" — which is exactly the gap `zz-design-4a`'s end marker fell
/// through under `konoma-orthogonal`'s own tighter node spacing
/// (`orthogonal::clear_foreign_cluster_overlaps`'s own doc has the dagre/nodesep reasoning).
pub(super) fn check_foreign_nodes_stay_out_of_clusters(
name: &str,
d: &Diagram,
tree: &clusters::Tree,
) {
for c in &d.clusters {
let frame = c.bounds();
for n in &d.nodes {
if tree.touches(&n.id, &c.id) {
continue;
}
let (dx, dy) = rect_overlap(n.bounds(), frame);
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: node {} (not a member) overlaps frame {} by {dx:.2}x{dy:.2}px",
n.id,
c.id
);
}
}
}
/// (6c) §10-5 round 4: under `konoma-orthogonal` a frame is not merely *big enough* for its
/// members — it is **derived** from them. Every side sits exactly [`clusters::PAD`] beyond the
/// members' own bounding box, plus the title's band at the top, and the box is only ever widened
/// symmetrically for a title too wide for it (`super::rebuild_frames`).
///
/// (6) alone cannot state this: dagre's own border-node rectangle held its members too, and it was
/// still stale — lopsided around them by however far the post-dagre passes had moved one. What the
/// exact derivation buys is the frame's own *centre*, which is what
/// [`super::orthogonal::classify`] measures a cluster-anchored edge's alignment against and what
/// [`super::orthogonal::evict`] hands out ports around; a frame merely "big enough" makes a
/// dead-straight lane through a block impossible to draw.
pub(super) fn check_frames_are_derived_from_members(
name: &str,
d: &Diagram,
tree: &clusters::Tree,
) {
for c in &d.clusters {
let mut bbox: Option<(f64, f64, f64, f64)> = None;
let mut hold = |(l, t, r, b): (f64, f64, f64, f64)| {
bbox = Some(match bbox {
Some((cl, ct, cr, cb)) => (cl.min(l), ct.min(t), cr.max(r), cb.max(b)),
None => (l, t, r, b),
});
};
for child in d
.clusters
.iter()
.filter(|k| k.parent.as_deref() == Some(&c.id))
{
hold(child.bounds());
}
if let Some(block) = tree.get(&c.id) {
for m in &block.member_nodes {
if let Some(n) = d.nodes.iter().find(|n| &n.id == m) {
hold(n.bounds());
}
}
}
let Some((l, t, r, b)) = bbox else { continue };
let pad = clusters::PAD;
let band = if c.title.is_blank() {
0.0
} else {
c.title.height + clusters::TITLE_PAD_Y * 2.0
};
let (fl, ft, fr, fb) = c.bounds();
// A title wider than its contents pushes both sides out by the same amount, so the *width*
// may exceed the derived one — but never asymmetrically, and never at top or bottom.
let widened = ((fr - fl) - (r - l + 2.0 * pad)).max(0.0) / 2.0;
for (label, got, want) in [
("left", fl, l - pad - widened),
("right", fr, r + pad + widened),
("top", ft, t - pad - band),
("bottom", fb, b + pad),
] {
assert!(
(got - want).abs() <= 0.01,
"{name}: frame {} {label} edge is {got:.2}, derived from its members it should be \
{want:.2}",
c.id
);
}
}
}
#[test]
fn invariant_clusters_hold_their_members() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_clusters_hold_their_members(name, &laid_out(src), &tree_of_src(src));
}
}
/// (6c) over every orthogonal fixture there is, including the design references — the invariant
/// `super::rebuild_frames` exists to satisfy, stated against the real render rather than against
/// the function's own arithmetic.
#[test]
fn invariant_orthogonal_frames_are_derived_from_their_members() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
check_frames_are_derived_from_members(name, &d, &tree_of_src(src));
}
}
/// (7) A nested frame is inside the frame that contains it.
pub(super) fn check_nested_clusters_sit_inside_their_parent(name: &str, d: &Diagram) {
for c in &d.clusters {
let Some(parent) = c.parent.as_deref().and_then(|p| d.cluster(p)) else {
continue;
};
let out = escapes(c.bounds(), parent.bounds());
assert!(
out <= 0.01,
"{name}: frame {} pokes {out:.2}px out of its parent {}",
c.id,
parent.id
);
}
}
#[test]
fn invariant_nested_clusters_sit_inside_their_parent() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_nested_clusters_sit_inside_their_parent(name, &laid_out(src));
}
}
/// (8) Two frames that are not one inside the other do not overlap.
///
/// Stated over every pair rather than over siblings only: `left` and `right` in `subgraph-
/// siblings` share a parent, but `inner` and an unrelated top-level block do not, and the two
/// boxes overlapping would be just as wrong.
pub(super) fn check_unrelated_clusters_do_not_overlap(name: &str, d: &Diagram) {
let nested = |d: &Diagram, a: &PlacedCluster, b: &PlacedCluster| {
let mut cur = a.parent.clone();
while let Some(p) = cur {
if p == b.id {
return true;
}
cur = d.cluster(&p).and_then(|c| c.parent.clone());
}
false
};
for (i, a) in d.clusters.iter().enumerate() {
for b in d.clusters.iter().skip(i + 1) {
if nested(d, a, b) || nested(d, b, a) {
continue;
}
let (dx, dy) = rect_overlap(a.bounds(), b.bounds());
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: frames {} and {} overlap by {dx:.2}x{dy:.2}px",
a.id,
b.id
);
}
}
}
#[test]
fn invariant_unrelated_clusters_do_not_overlap() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_unrelated_clusters_do_not_overlap(name, &laid_out(src));
}
}
/// (9) A line does not run through a frame it has no business being in.
///
/// The distinction the test turns on is [`clusters::Tree::touches`]: an edge with one end inside
/// a block *must* cross that block's border, and clipping it there would cut the line off from
/// its own node. An edge with neither end under the block has no reason to be inside it at all —
/// dagre's compound layout keeps it out (that is what `parentDummyChains` is for), and this is
/// what proves the clusters really were handed to dagre rather than drawn on afterwards.
///
/// **An edge that *names* a block is exempt, and the exemption is a known gap, not a rule.**
/// dagre cannot route to a compound parent, so such an edge is laid out against a stand-in leaf
/// inside the block ([`clusters::Tree::anchor`]) and cut back to the frame only when it is drawn.
/// dagre therefore never saw the endpoints the reader wrote, and nothing constrains the route it
/// chose between the two stand-ins to stay out of a *third* block that happens to sit between
/// them. [`an_edge_that_names_a_block_is_not_kept_clear_of_its_surroundings`] records both halves of
/// the reason it is `#[ignore]`d: it is a property of the vendored layout that predates state
/// diagrams, not something stage 2 introduced, and papering over it here would turn a bug into a
/// specification.
pub(super) fn check_edges_keep_out_of_foreign_frames(
name: &str,
d: &Diagram,
tree: &clusters::Tree,
) {
for e in &d.edges {
// See the doc comment: an edge whose own endpoint is a block was routed between two
// stand-ins, so the layout was never asked the question this invariant poses.
if tree.contains(&e.from) || tree.contains(&e.to) {
continue;
}
for c in &d.clusters {
if tree.touches(&e.from, &c.id) || tree.touches(&e.to, &c.id) {
continue;
}
let depth = polyline_depth_in_rect(&e.drawn_points(), c.bounds());
assert!(
depth <= 0.5,
"{name}: edge {} -> {} runs {depth:.2}px into frame {}",
e.from,
e.to,
c.id
);
}
}
}
#[test]
fn invariant_edges_keep_out_of_frames_they_do_not_belong_to() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_edges_keep_out_of_foreign_frames(name, &laid_out(src), &tree_of_src(src));
}
}
/// (10) An edge that names a block starts or ends **on that block's frame**, and never inside it.
///
/// `one --> two` is legal mermaid (§2-2) and dagre cannot route it — a compound parent has no
/// rank. The line is laid out against a member and then cut back to the boundary, which is the
/// only thing that makes the arrow point at the box rather than at some node the author never
/// mentioned.
pub(super) fn check_edge_that_names_a_block_stops_on_its_frame(
name: &str,
d: &Diagram,
tree: &clusters::Tree,
) {
for e in &d.edges {
for (end, id) in [("tail", &e.from), ("head", &e.to)] {
if !tree.contains(id) {
continue;
}
let c = d
.cluster(id)
.unwrap_or_else(|| panic!("{name}: edge names block {id} but no frame was placed"));
let frame = c.bounds();
let point = if end == "tail" {
e.points.first()
} else {
e.points.last()
}
.expect("an edge has points");
let on_edge = (point.x - frame.0)
.abs()
.min((point.x - frame.2).abs())
.min((point.y - frame.1).abs())
.min((point.y - frame.3).abs());
assert!(
on_edge <= 0.01,
"{name}: the {end} of {} -> {} is {on_edge:.2}px off frame {id}",
e.from,
e.to
);
let depth = polyline_depth_in_rect(&e.drawn_points(), frame);
assert!(
depth <= 0.5,
"{name}: {} -> {} is drawn {depth:.2}px inside frame {id}",
e.from,
e.to
);
}
}
}
#[test]
fn invariant_an_edge_that_names_a_block_stops_on_its_frame() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_edge_that_names_a_block_stops_on_its_frame(name, &laid_out(src), &tree_of_src(src));
}
}
/// (11) A title is inside its own frame and on top of nothing.
///
/// Both halves matter and they pull in opposite directions: pushing the title further in to clear
/// the members eventually pushes it onto them from the other side, and the only reason there is
/// room at all is that dagre leaves a band above the topmost rank. A frame that had to grow to
/// make that band big enough is exactly the case this catches.
pub(super) fn check_cluster_titles(name: &str, d: &Diagram, tree: &clusters::Tree) {
for c in &d.clusters {
if c.title.is_blank() {
continue;
}
let t = c.title_center();
let title = (
t.x - c.title.width / 2.0,
t.y - c.title.height / 2.0,
t.x + c.title.width / 2.0,
t.y + c.title.height / 2.0,
);
let out = escapes(title, c.bounds());
assert!(
out <= 0.01,
"{name}: the title of {} pokes {out:.2}px out of its own frame",
c.id
);
for n in &d.nodes {
if !tree.touches(&n.id, &c.id) {
continue;
}
let (dx, dy) = rect_overlap(title, n.bounds());
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: the title of {} sits on node {} ({dx:.2}x{dy:.2}px)",
c.id,
n.id
);
}
for other in &d.clusters {
if other.parent.as_deref() != Some(c.id.as_str()) {
continue;
}
let (dx, dy) = rect_overlap(title, other.bounds());
assert!(
dx <= 0.01 || dy <= 0.01,
"{name}: the title of {} sits on the nested frame {} ({dx:.2}x{dy:.2}px)",
c.id,
other.id
);
}
}
}
/// (12) Every row of a compartmented box is **inside the box**, and every rule that separates the
/// rows lies on the box.
///
/// The one thing a [`Panel`](super::panel::Panel) can get wrong that nothing else notices: it is
/// the only geometry in the renderer that is stated in coordinates *relative to a node*, so a
/// sizing mistake shows up as text hanging out of a class box rather than as an overlap the other
/// invariants would catch. Both halves are needed — a panel sized too small clips its own rows,
/// and a rule computed from the wrong height draws across the diagram.
pub(super) fn check_panels_stay_inside_their_box(name: &str, d: &Diagram) {
for n in &d.nodes {
let Some(panel) = &n.panel else { continue };
assert!(
(panel.size.w - n.size.w).abs() < 0.01 && (panel.size.h - n.size.h).abs() < 0.01,
"{name}: {} is {}x{} but its panel is {}x{}",
n.id,
num(n.size.w),
num(n.size.h),
num(panel.size.w),
num(panel.size.h)
);
for (l, t, r, b) in panel.cell_bounds() {
assert!(
l >= -0.01 && t >= -0.01 && r <= n.size.w + 0.01 && b <= n.size.h + 0.01,
"{name}: a row of {} runs from ({}, {}) to ({}, {}), outside its {}x{} box",
n.id,
num(l),
num(t),
num(r),
num(b),
num(n.size.w),
num(n.size.h)
);
}
for y in &panel.rules {
assert!(
*y >= -0.01 && *y <= n.size.h + 0.01,
"{name}: a rule of {} is at y={} in a box {} tall",
n.id,
num(*y),
num(n.size.h)
);
}
for x in &panel.columns {
assert!(
*x >= -0.01 && *x <= n.size.w + 0.01,
"{name}: a column rule of {} is at x={} in a box {} wide",
n.id,
num(*x),
num(n.size.w)
);
}
}
}
#[test]
fn invariant_cluster_titles_stay_in_the_frame_and_off_the_members() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
check_cluster_titles(name, &laid_out(src), &tree_of_src(src));
}
}
/// **A known gap, recorded rather than papered over.** An edge that *names a block* is laid out
/// between stand-in leaves, so nothing keeps its route clear of what happens to lie beside it: it
/// can cross a third block, and it can graze a node.
///
/// dagre cannot route to a compound parent — the ranking phase only ever sees leaves — so
/// [`clusters::Tree::anchor`] hands it a descendant instead, and `edges::route` cuts the result
/// back to the frame only when it is drawn. Between those two steps the endpoint the author wrote
/// does not exist as far as the layout is concerned. mermaid solves it the same way and has the
/// same gap.
///
/// Measured on **flowcharts** on purpose. Both halves reproduce identically in state diagrams
/// (`composite-siblings` and `direction-lr` in [`super::state_tests::CASES`]), so this is a
/// property of stage 1's re-anchoring rather than something stage 2 brought in — which is the
/// difference between a limitation to record and a regression to fix. Closing it means
/// constraining the route, which is a change to how a cluster endpoint reaches dagre, not a
/// tolerance to widen. `#[ignore]`d with the reason rather than deleted, following the convention
/// konoma used for the nested `<details>` ordinal bug: the test says what *should* be true, and
/// it fails for as long as it is not.
#[test]
#[ignore = "known gap: an edge naming a block is routed between stand-in leaves, so neither a third block between them nor a node beside them is avoided. Reproduces in mermaid too; needs a change to how a cluster endpoint reaches dagre."]
fn an_edge_that_names_a_block_is_not_kept_clear_of_its_surroundings() {
if !text_metrics::fonts_available() {
return;
}
// (a) the route crosses a third block that sits between the two it joins.
let src = "flowchart TD\n Z --> one\n one --> two\n one --> three\n subgraph one [First]\n a --> b\n end\n subgraph two [Second]\n c --> d\n end\n subgraph three [Third]\n e --> f\n end";
let d = laid_out(src);
let tree = tree_of_src(src);
for e in &d.edges {
for c in &d.clusters {
if tree.touches(&e.from, &c.id) || tree.touches(&e.to, &c.id) {
continue;
}
let depth = polyline_depth_in_rect(&e.drawn_points(), c.bounds());
assert!(
depth <= 0.5,
"edge {} -> {} runs {depth:.2}px into frame {}",
e.from,
e.to,
c.id
);
}
}
// (b) the route grazes a node standing beside the frame it leaves.
let src = "flowchart LR\n Z --> A\n A --> B\n B --> C\n B --> D\n subgraph B [B]\n a --> b\n end";
let d = laid_out(src);
let outlines: Vec<Vec<Point>> = d.nodes.iter().map(boundary).collect();
for e in &d.edges {
for p in e.drawn_points() {
for (node, poly) in d.nodes.iter().zip(&outlines) {
let inside_by = depth(&p, poly);
assert!(
inside_by <= 1.0,
"edge {} -> {} runs {}px inside {}",
e.from,
e.to,
num(inside_by),
node.id
);
}
}
}
}
/// Every block the author wrote gets a frame, and every frame is a block the author wrote.
///
/// The second half is the one that matters: a frame around a group nobody declared is a lie about
/// the diagram, and it is what a bug in the tree-building would produce.
#[test]
fn every_block_that_holds_a_node_gets_exactly_one_frame() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
let d = laid_out(src);
let tree = tree_of_src(src);
let drawn: HashSet<&str> = d.clusters.iter().map(|c| c.id.as_str()).collect();
assert_eq!(
drawn.len(),
d.clusters.len(),
"{name}: a frame is drawn twice"
);
let declared: HashSet<&str> = tree.iter().map(|c| c.id.as_str()).collect();
assert_eq!(drawn, declared, "{name}: frames and blocks disagree");
}
}
/// Everything the author wrote is on the page: one shape per node, and one line per edge — an
/// edge that names a block included, now that a block is something a line can end on. A dropped
/// node is how a renderer quietly lies about a diagram.
#[test]
fn every_node_and_drawable_edge_survives() {
for (name, src) in CORPUS {
let chart = parse(src).expect("parses");
let tree = tree_of_src(src);
let d = laid_out(src);
assert_eq!(d.nodes.len(), chart.nodes.len(), "{name}: node count");
let drawable = chart
.edges
.iter()
.filter(|e| {
let end = |id: &str| chart.node(id).is_some() || tree.contains(id);
end(&e.from) && end(&e.to)
})
.count();
assert_eq!(d.edges.len(), drawable, "{name}: edge count");
}
}
// ---------------------------------------------------------------------------------------------
// 3. The shape formulas, stated as arithmetic
// ---------------------------------------------------------------------------------------------
/// A label size with no font behind it, so these tests say the same thing on every machine.
const L: Size = Size { w: 100.0, h: 20.0 };
/// mermaid's `question.ts`: `w = label + padding`, `h = label + padding`, and the drawn square's
/// side is **`w + h`**, not `w`.
///
/// This is the formula that matters most to a reader: sizing a decision box like a rectangle puts
/// its branch labels on top of it. A mutation to `s = w` has to fail here.
#[test]
fn diamond_side_is_the_sum_of_both_padded_axes() {
let s = flow_size(Shape::Diamond, L);
let expected = (L.w + shapes::PADDING) + (L.h + shapes::PADDING);
assert_eq!(s.w, expected);
assert_eq!(s.h, expected);
// …and it really is a square standing on its corner.
let p = shapes::polygon(Glyph::Flow(Shape::Diamond), s);
assert_eq!(p.len(), 4);
assert_eq!((p[0].x, p[0].y), (0.0, -expected / 2.0));
assert_eq!((p[1].x, p[1].y), (expected / 2.0, 0.0));
}
/// `squareRect.ts` -> `drawRect.ts`: `labelPaddingX` is `padding * 2` and `drawRect` doubles it,
/// while `labelPaddingY` is `padding * 1` and is doubled too — so a rectangle is four paddings
/// wider and two paddings taller than its label.
#[test]
fn rect_padding_is_four_by_two() {
let s = flow_size(Shape::Rect, L);
assert_eq!(s.w, L.w + shapes::PADDING * 4.0);
assert_eq!(s.h, L.h + shapes::PADDING * 2.0);
}
/// `stadium.ts`: the height gets **one** padding, not two, and the width carries a quarter of the
/// height for the two caps.
#[test]
fn stadium_height_takes_a_single_padding() {
let s = flow_size(Shape::Stadium, L);
let h = L.h + shapes::PADDING;
assert_eq!(s.h, h);
assert_eq!(s.w, L.w + h / 4.0 + shapes::PADDING);
// The outline is a rectangle whose corner radius closes the ends into semicircles.
assert_eq!(
shapes::outline(Glyph::Flow(Shape::Stadium), s, None),
shapes::Outline::Rect {
w: s.w,
h: s.h,
r: s.h / 2.0
}
);
}
/// `circle.ts` sizes the ring from the label's **width alone**, so a circle is always round.
#[test]
fn circle_radius_follows_the_label_width() {
let s = flow_size(Shape::Circle, L);
assert_eq!(s.w, s.h);
assert_eq!(s.w, L.w + shapes::PADDING * 2.0);
}
/// `hexagon.ts`: the slanted ends are `h/4` wide each, so the box is half a height wider than the
/// padded label.
#[test]
fn hexagon_ends_are_a_quarter_of_its_height() {
let s = flow_size(Shape::Hexagon, L);
let h = L.h + shapes::PADDING;
assert_eq!(s.h, h);
assert_eq!(s.w, L.w + h / 2.0 + shapes::PADDING);
let p = shapes::polygon(Glyph::Flow(Shape::Hexagon), s);
assert_eq!(p.len(), 6);
assert_eq!(p[0].x, -s.w / 2.0 + h / 4.0);
}
/// `trapezoid.ts` takes one padding per axis while `invertedTrapezoid.ts` doubles both. The
/// asymmetry is upstream's; recording it here stops it being "tidied up" into a bug.
#[test]
fn trapezoid_and_inverted_trapezoid_pad_differently() {
let up = flow_size(Shape::Trapezoid, L);
let down = flow_size(Shape::InvTrapezoid, L);
assert_eq!(up.h, L.h + shapes::PADDING);
assert_eq!(down.h, L.h + shapes::PADDING * 2.0);
assert_eq!(up.w, L.w + shapes::PADDING + up.h);
assert_eq!(down.w, L.w + shapes::PADDING * 2.0 + down.h);
// The wide side is the bottom for one and the top for the other.
let (a, b) = (
shapes::polygon(Glyph::Flow(Shape::Trapezoid), up),
shapes::polygon(Glyph::Flow(Shape::InvTrapezoid), down),
);
assert!(
a[0].y > 0.0 && a[0].x == -up.w / 2.0,
"trapezoid is wide at the bottom"
);
assert!(
b[2].y < 0.0 && b[2].x == down.w / 2.0,
"inv trapezoid is wide at the top"
);
}
/// **The label fits inside the shape that was sized for it.**
///
/// Stated over the outline, not the bounding box, because that is where sizing goes wrong: a
/// diamond sized `s = w` instead of `s = w + h` still has a perfectly reasonable bounding box and
/// still puts its text outside the rhombus. Checking the four corners of the label rectangle is
/// what turns "the formula is the one mermaid uses" into "the diagram reads".
///
/// Circles are the documented exception: `circle.ts` derives the radius from the label's **width
/// alone**, so a tall label overflows upstream too. konoma keeps mermaid's formula here (see
/// `shapes::size`) and records the limitation rather than quietly diverging.
#[test]
fn every_shape_holds_the_label_it_was_sized_for() {
for shape in [
Shape::Rect,
Shape::RoundedRect,
Shape::Stadium,
Shape::Subroutine,
Shape::Cylinder,
Shape::Diamond,
Shape::Hexagon,
Shape::Odd,
Shape::Trapezoid,
Shape::InvTrapezoid,
Shape::LeanRight,
Shape::LeanLeft,
Shape::Text,
] {
let size = flow_size(shape, L);
let node = PlacedNode {
id: format!("{shape:?}"),
shape: Glyph::Flow(shape),
center: Point::new(0.0, 0.0),
size,
label: Label {
lines: vec!["x".to_string()],
width: L.w,
height: L.h,
line_pitch: L.h,
font_size: crate::preview::mermaid::text_metrics::FONT_SIZE as f64,
},
panel: None,
series: None,
mark: None,
style: None,
};
let outline = boundary(&node);
for (sx, sy) in [(-1.0, -1.0), (1.0, -1.0), (1.0, 1.0), (-1.0, 1.0)] {
let corner = Point::new(sx * L.w / 2.0, sy * L.h / 2.0);
assert!(
inside(&corner, &outline),
"{shape:?}: a {}x{} label reaches ({}, {}), which is outside the {}x{} outline",
num(L.w),
num(L.h),
num(corner.x),
num(corner.y),
num(size.w),
num(size.h)
);
}
}
// What mermaid does guarantee for a circle: the label's width fits across it.
for shape in [Shape::Circle, Shape::DoubleCircle] {
let size = flow_size(shape, L);
assert!(size.w >= L.w, "{shape:?}: the label is wider than the ring");
}
}
/// A diamond's edges leave from its slanted sides, which is the whole point of intersecting the
/// outline instead of the bounding box. A point due east of the centre leaves at the right
/// corner; a point to the north-east leaves part-way along the upper-right side, strictly inside
/// the bounding box's corner.
#[test]
fn diamond_intersection_uses_the_slanted_sides() {
let s = Size::new(100.0, 100.0);
let c = Point::new(0.0, 0.0);
let east = shapes::intersect(
Glyph::Flow(Shape::Diamond),
c.clone(),
s,
&Point::new(500.0, 0.0),
);
assert!((east.x - 50.0).abs() < 1e-9 && east.y.abs() < 1e-9);
let ne = shapes::intersect(
Glyph::Flow(Shape::Diamond),
c,
s,
&Point::new(500.0, -500.0),
);
// On the side |x| + |y| = 50, and well inside the box corner (50, -50).
assert!(
(ne.x.abs() + ne.y.abs() - 50.0).abs() < 1e-9,
"on the slanted side"
);
assert!(
ne.x < 49.0 && ne.y > -49.0,
"not at the bounding box's corner"
);
}
// ---------------------------------------------------------------------------------------------
// 4. Edge geometry
// ---------------------------------------------------------------------------------------------
/// d3's `curveBasis` — mermaid's default. It touches the first and last point and **no** other:
/// the rest are control points. Pinning the exact `d` for three known points fixes the whole
/// construction, ends included (d3 draws a straight sixth of the first and last segment).
#[test]
fn curve_basis_matches_d3() {
let pts = [
Point::new(0.0, 0.0),
Point::new(60.0, 0.0),
Point::new(60.0, 60.0),
];
assert_eq!(
edges::curve_basis_path(&pts),
"M0,0L10,0C20,0 40,0 50,10C60,20 60,40 60,50L60,60"
);
// Two points are just a line; one is just a move.
assert_eq!(edges::curve_basis_path(&pts[..2]), "M0,0L60,0");
assert_eq!(edges::curve_basis_path(&pts[..1]), "M0,0");
// Collinear points (vertical, horizontal) and a duplicated point — this section's own
// `VERTICAL`/`HORIZONTAL`/`DUPLICATE` module docs have the reason these three shapes are
// swept over every curve, `basis` included even though it was never the one that broke.
let vertical = [
Point::new(100.0, 50.0),
Point::new(100.0, 120.0),
Point::new(100.0, 190.0),
];
assert_eq!(
edges::curve_basis_path(&vertical),
"M100,50L100,61.667C100,73.333 100,96.667 100,120\
C100,143.333 100,166.667 100,178.333L100,190"
);
let horizontal = [
Point::new(50.0, 100.0),
Point::new(120.0, 100.0),
Point::new(190.0, 100.0),
];
assert_eq!(
edges::curve_basis_path(&horizontal),
"M50,100L61.667,100C73.333,100 96.667,100 120,100\
C143.333,100 166.667,100 178.333,100L190,100"
);
let duplicate = [
Point::new(0.0, 0.0),
Point::new(40.0, 40.0),
Point::new(40.0, 40.0),
Point::new(80.0, 80.0),
];
assert_eq!(
edges::curve_basis_path(&duplicate),
"M0,0L6.667,6.667C13.333,13.333 26.667,26.667 33.333,33.333\
C40,40 40,40 46.667,46.667C53.333,53.333 66.667,66.667 73.333,73.333L80,80"
);
}
/// `edges.js`'s `fixCorners` rounds a right angle off with a radius of 5, replacing the corner
/// with three points. A bend that is too shallow to matter is left alone.
#[test]
fn fix_corners_rounds_right_angles_only() {
let square = [
Point::new(0.0, 0.0),
Point::new(0.0, 100.0),
Point::new(100.0, 100.0),
];
let fixed = edges::fix_corners(&square);
assert_eq!(fixed.len(), 5, "the corner becomes three points");
assert!(
fixed[1].y < 100.0 && fixed[3].x > 0.0,
"the replacement points step back from the corner"
);
// A corner whose arms are shorter than the 5px test is not a corner.
let tiny = [
Point::new(0.0, 0.0),
Point::new(0.0, 4.0),
Point::new(4.0, 4.0),
];
assert_eq!(edges::fix_corners(&tiny).len(), 3);
// A straight line has nothing to round.
let straight = [
Point::new(0.0, 0.0),
Point::new(0.0, 50.0),
Point::new(0.0, 100.0),
];
assert_eq!(edges::fix_corners(&straight).len(), 3);
}
/// The label goes at the half-way point **by arc length**, so uneven waypoint spacing does not
/// drag it towards the crowded end. mermaid's `traverseEdge`.
#[test]
fn arc_midpoint_is_measured_by_length_not_by_waypoint() {
// Three waypoints, but the second sits at 90% of the length: a "middle waypoint" rule would
// answer (90, 0) where the real midpoint is (50, 0).
let line = [
Point::new(0.0, 0.0),
Point::new(90.0, 0.0),
Point::new(100.0, 0.0),
];
let mid = edges::arc_midpoint(&line).expect("has a midpoint");
assert!((mid.x - 50.0).abs() < 1e-9 && mid.y.abs() < 1e-9);
assert_eq!(edges::arc_midpoint(&[]), None);
}
/// An arrow head is `ARROW_LENGTH` long, points along the last segment, and has its tip exactly
/// on the point it was given — the point clipping put on the shape's outline.
#[test]
fn arrow_head_points_along_the_last_segment() {
let head = edges::arrow_head(&Point::new(0.0, 0.0), &Point::new(0.0, 100.0));
assert_eq!((head[0].x, head[0].y), (0.0, 100.0));
assert!((head[1].y - (100.0 - edges::ARROW_LENGTH)).abs() < 1e-9);
assert!((head[1].x - head[2].x).abs() - edges::ARROW_HALF_WIDTH * 2.0 < 1e-9);
}
/// Every flowchart arrow spelling puts a mark on **exactly the ends it names**, and nothing on
/// the end it does not.
///
/// Until this test existed the whole arrow family was guarded by the two goldens alone, and a
/// mutation proved what that is worth: turning `Tip::of_arrow(Arrow::Point)` from
/// `(Tip::None, Tip::Arrow)` into `(Tip::Arrow, Tip::Arrow)` — a one-way arrow quietly growing a
/// second head — reddened `emit_golden` and `corpus_golden` and **not one named test**. That is
/// the shape `docs/STATUS.md` records as having cost konoma twice: behaviour a golden alone holds
/// is lost silently the next time the golden is regenerated. The class and ER families already
/// had their own version of this check
/// ([`super::er_tests::a_crows_foot_is_drawn_at_the_end_that_asked_for_it`]); the flowchart family
/// did not.
///
/// Stated twice on purpose. Once about the **model**, which end asked for which mark, and once
/// about the **drawing**, how many of each mark actually reach the page — `svg::emit_edge` decides
/// for itself what a `Tip` looks like, so the two can disagree.
#[test]
fn a_flowchart_arrow_marks_only_the_ends_that_spelled_a_mark() {
if !text_metrics::fonts_available() {
return;
}
// (what the author wrote, what it parses to, the mark at the tail, the mark at the head).
let cases: &[(&str, Arrow, Tip, Tip)] = &[
("---", Arrow::None, Tip::None, Tip::None),
("-->", Arrow::Point, Tip::None, Tip::Arrow),
("--x", Arrow::Cross, Tip::None, Tip::Cross),
("--o", Arrow::Circle, Tip::None, Tip::Circle),
("<-->", Arrow::DoublePoint, Tip::Arrow, Tip::Arrow),
("x--x", Arrow::DoubleCross, Tip::Cross, Tip::Cross),
("o--o", Arrow::DoubleCircle, Tip::Circle, Tip::Circle),
// The two halves of an infix link disagreeing (§2-6 rule 6). mermaid calls it `INVALID`
// and konoma draws the shaft with nothing on either end, rather than guessing.
("x-- t -->", Arrow::Invalid, Tip::None, Tip::None),
];
// The table covers the whole enum: a new `Arrow` variant makes `covered` fail to compile, and
// a variant left out of the table fails here.
fn covered(a: Arrow) -> bool {
match a {
Arrow::None
| Arrow::Point
| Arrow::Cross
| Arrow::Circle
| Arrow::DoublePoint
| Arrow::DoubleCross
| Arrow::DoubleCircle
| Arrow::Invalid => true,
}
}
let spelled: HashSet<Arrow> = cases.iter().map(|(_, a, _, _)| *a).collect();
assert_eq!(spelled.len(), cases.len(), "an arrow is spelled twice");
for a in &spelled {
assert!(covered(*a));
}
// How many marks of each kind the emitted document actually carries. Both nodes are `[]`
// rectangles, so a `<polygon>` can only be an arrow head and a `<circle>` can only be a `--o`
// disc; a `--x` is the one `<path>` whose `d` carries a second `M` (a curve never does).
let drawn = |svg: &str| -> (usize, usize, usize) {
let heads = svg.matches("<polygon").count();
let crosses = svg
.lines()
.filter(|l| l.starts_with("<path") && l.matches('M').count() > 1)
.count();
let discs = svg.matches("<circle").count();
(heads, crosses, discs)
};
let wanted = |tip: Tip| -> (usize, usize, usize) {
match tip {
Tip::Arrow => (1, 0, 0),
Tip::Cross => (0, 1, 0),
Tip::Circle => (0, 0, 1),
_ => (0, 0, 0),
}
};
for (spelling, arrow, tip_start, tip_end) in cases {
let src = format!("flowchart LR\n A[a] {spelling} B[b]\n");
let chart = parse(&src).unwrap_or_else(|e| panic!("{spelling}: {e}"));
assert_eq!(chart.edges.len(), 1, "{spelling}: one edge");
assert_eq!(chart.edges[0].arrow, *arrow, "{spelling}: parsed arrow");
let d = laid_out(&src);
assert_eq!(d.edges.len(), 1, "{spelling}: one edge survives layout");
let e = &d.edges[0];
assert_eq!(
(e.tip_start, e.tip_end),
(*tip_start, *tip_end),
"{spelling}: the marks are on the wrong ends"
);
let svg = render(&src, "dark").expect("renders");
let (heads, crosses, discs) = drawn(&svg);
let (ws, wc, wd) = wanted(*tip_start);
let (we, wcc, wdd) = wanted(*tip_end);
assert_eq!(
(heads, crosses, discs),
(ws + we, wc + wcc, wd + wdd),
"{spelling}: {heads} arrow heads, {crosses} crosses and {discs} discs were drawn for \
({tip_start:?}, {tip_end:?})"
);
}
}
/// The line is pulled back so the arrow head has room, but never past the point of having no
/// direction left.
#[test]
fn trimming_leaves_a_line_with_a_direction() {
let line = [Point::new(0.0, 0.0), Point::new(0.0, 100.0)];
let cut = edges::trim_end(&line, edges::ARROW_LENGTH);
assert!((cut.last().unwrap().y - 91.0).abs() < 1e-9);
let stub = [Point::new(0.0, 0.0), Point::new(0.0, 3.0)];
assert_eq!(edges::trim_end(&stub, edges::ARROW_LENGTH), stub.to_vec());
}
/// `~~~` is a layout constraint that draws nothing, and it must still have moved the layout.
#[test]
fn invisible_edge_constrains_but_does_not_draw() {
let with = laid_out("flowchart TD\n A[aaa]\n B[bbb]\n A ~~~ B");
let without = laid_out("flowchart TD\n A[aaa]\n B[bbb]");
assert!(
with.height > without.height,
"the invisible edge should have pushed B onto its own rank"
);
let svg = render("flowchart TD\n A[aaa]\n B[bbb]\n A ~~~ B", "dark").expect("renders");
assert_eq!(
svg.matches("<path").count(),
0,
"an invisible edge emits no path"
);
}
// ---------------------------------------------------------------------------------------------
// 5. The SVG contract (§1) and the round trip through resvg
// ---------------------------------------------------------------------------------------------
/// §1's constraints, each of which is a thing resvg was measured doing rather than a style rule.
#[test]
fn emitted_svg_obeys_the_renderer_contract() {
for (name, src) in CORPUS {
for theme_name in ["dark", "light", "classic", "forest", "neutral"] {
let svg = render(src, theme_name).expect("renders");
assert!(
svg.contains("viewBox=\""),
"{name}/{theme_name}: without a viewBox usvg falls back to 100x100"
);
assert!(svg.contains("width=\"") && svg.contains("height=\""));
assert!(
!svg.contains("foreignObject"),
"{name}/{theme_name}: resvg drops <foreignObject> whole, label and all"
);
assert!(
!svg.contains("var(--"),
"{name}/{theme_name}: usvg cannot resolve CSS variables — fills go black"
);
assert!(
!svg.contains("<style") && !svg.contains("class=\"node default\""),
"{name}/{theme_name}: nothing may depend on a stylesheet"
);
assert!(
svg.contains("font-family=\"sans-serif\""),
"{name}/{theme_name}: the drawing font must be the one that was measured"
);
// The only full-canvas rect is the transparent one.
let opaque_background = svg
.lines()
.any(|l| l.starts_with("<rect width=") && !l.contains("fill=\"none\""));
assert!(
!opaque_background,
"{name}/{theme_name}: an opaque background turns the diagram into a card"
);
}
}
}
/// The output goes through konoma's own rasteriser, which is the thing that will actually draw it.
#[test]
fn every_corpus_diagram_rasterises() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in CORPUS {
let svg = render(src, "dark").expect("renders");
let img = crate::preview::svg::rasterize_bytes(svg.as_bytes(), FsPath::new("m.svg"), 600)
.unwrap_or_else(|| panic!("{name}: konoma's resvg could not rasterise the output"));
assert!(img.width() > 0 && img.height() > 0, "{name}: empty raster");
}
}
/// A diagram that draws nothing at all would rasterise to a transparent rectangle, which is
/// exactly the failure §6 calls out in the current crate (`graph TD` alone becoming a 16x16
/// transparent SVG blown up to full width). Some ink has to reach the pixmap.
#[test]
fn a_rendered_diagram_actually_has_ink_in_it() {
if !text_metrics::fonts_available() {
return;
}
let svg = render("flowchart TD\n A[Start] --> B{Ready?}", "dark").expect("renders");
let img = crate::preview::svg::rasterize_bytes(svg.as_bytes(), FsPath::new("m.svg"), 400)
.expect("rasterises");
let opaque = img.to_rgba8().pixels().filter(|p| p.0[3] > 32).count();
assert!(
opaque > 500,
"only {opaque} pixels were drawn — the diagram is effectively blank"
);
}
// ---------------------------------------------------------------------------------------------
// 6. Themes (§4)
// ---------------------------------------------------------------------------------------------
/// Every colour is a normalised lowercase hex, and the background is never painted.
///
/// Over [`theme::EVERY_PALETTE`], not `theme::ALL`: `theme::KONOMA` is not a `[ui] mermaid_theme`
/// value (only `konoma-orthogonal` ever selects it) but it is still a palette, and a rule about
/// what a palette may contain is not weaker for the palette being reached a different way.
#[test]
fn every_theme_colour_is_normalised_hex() {
for t in theme::EVERY_PALETTE {
assert_eq!(
t.background_paint, "none",
"{}: the background is a reference colour, never a paint (§4-2)",
t.name
);
for (field, value) in [
("background_ref", t.background_ref),
("node_fill", t.node_fill),
("node_stroke", t.node_stroke),
("node_text", t.node_text),
("line", t.line),
("arrowhead", t.arrowhead),
("edge_label_text", t.edge_label_text),
("cluster_fill", t.cluster_fill),
("cluster_stroke", t.cluster_stroke),
("cluster_text", t.cluster_text),
("state_marker", t.state_marker),
("note_fill", t.note_fill),
("note_stroke", t.note_stroke),
("note_text", t.note_text),
] {
assert!(
theme::parse_hex(value).is_some(),
"{}.{field} = {value:?} is not a normalised #rrggbb",
t.name
);
}
}
}
/// **§4-1's decision, as a test.** konoma never paints a background, so a light theme's diagram
/// can end up composited on a dark terminal. mermaid's own `forest` resolves its line colour to
/// `#000000` (`invert(background)` on line 31 overwrites the `green` on line 17) and vanishes
/// there. Every light-series palette here must stay legible against **both** grounds; the dark
/// palette only has to answer for the dark one.
#[test]
fn lines_survive_being_composited_on_either_ground() {
const FLOOR: f64 = 2.2;
for t in theme::EVERY_PALETTE {
// `state_marker` is here and not with the fills below because it is the one *filled*
// shape with nothing behind it: the `[*]` dots and the fork bars are solid marks on the
// terminal itself, so a palette that picked a dark one would make them vanish outright
// rather than merely go faint.
for (field, colour) in [
("line", t.line),
("arrowhead", t.arrowhead),
("state_marker", t.state_marker),
] {
let on_black = Theme::contrast(colour, "#000000");
assert!(
on_black >= 3.0,
"{}.{field} = {colour} has contrast {:.2} on black — it disappears on a dark \
terminal (this is what happens to mermaid's forest)",
t.name,
on_black
);
if t.name != "dark" {
let on_white = Theme::contrast(colour, "#ffffff");
assert!(
on_white >= FLOOR,
"{}.{field} = {colour} has contrast {:.2} on white",
t.name,
on_white
);
}
}
// Node text has to read against the fill it is drawn on, whatever the terminal does.
assert!(
Theme::contrast(t.node_text, t.node_fill) >= 4.0,
"{}: node text {} on fill {} has contrast {:.2}",
t.name,
t.node_text,
t.node_fill,
Theme::contrast(t.node_text, t.node_fill)
);
// A note's text is drawn on the note's own fill, which is opaque, so this is the same
// question as node text and gets the same floor.
assert!(
Theme::contrast(t.note_text, t.note_fill) >= 4.0,
"{}: note text {} on fill {} has contrast {:.2}",
t.name,
t.note_text,
t.note_fill,
Theme::contrast(t.note_text, t.note_fill)
);
// An edge label is drawn on the reference colour, not on the terminal.
assert!(
Theme::contrast(t.edge_label_text, t.background_ref) >= 4.0,
"{}: edge label text {} on {} has contrast {:.2}",
t.name,
t.edge_label_text,
t.background_ref,
Theme::contrast(t.edge_label_text, t.background_ref)
);
}
}
/// The five names konoma promises, plus mermaid's own spellings — and an unknown value is `dark`,
/// silently, which is the behaviour `mermaid_to_svg` has today (§1).
#[test]
fn theme_names_resolve_the_way_the_config_promises() {
assert_eq!(Theme::named("dark").name, "dark");
assert_eq!(Theme::named("light").name, "light");
assert_eq!(Theme::named("modern").name, "light");
assert_eq!(Theme::named("classic").name, "classic");
assert_eq!(Theme::named("mermaid").name, "classic");
assert_eq!(Theme::named("forest").name, "forest");
assert_eq!(Theme::named("neutral").name, "neutral");
assert_eq!(Theme::named("").name, "dark");
assert_eq!(Theme::named("Dracula").name, "dark");
// `konoma` is **not** a `[ui] mermaid_theme` value — the palette of that name belongs to
// `[ui] mermaid_routing = "konoma-orthogonal"` and is reached only through
// `Theme::for_routing`. Writing it in `mermaid_theme` is a typo like any other, and a typo
// falls back to `dark` rather than changing what the diagram looks like.
assert_eq!(Theme::named("konoma").name, "dark");
}
/// `Theme::for_routing`: `konoma-orthogonal` owns its palette, `splines` defers to the theme.
///
/// Stated over **every** theme spelling the config accepts, so "the mode ignores the theme" cannot
/// be true for four values and false for the fifth.
#[test]
fn the_orthogonal_router_carries_its_own_palette() {
for name in [
"dark", "light", "modern", "classic", "mermaid", "forest", "neutral", "", "Dracula",
] {
assert_eq!(
Theme::for_routing(name, Routing::Orthogonal).name,
"konoma",
"mermaid_theme={name:?} must not reach a konoma-orthogonal drawing"
);
assert_eq!(
Theme::for_routing(name, Routing::Splines),
Theme::named(name),
"mermaid_theme={name:?} must decide a splines drawing by itself"
);
}
// And the two really are different palettes, so the assertion above is not vacuous.
assert_ne!(theme::KONOMA, Theme::named("dark"));
// Only the orthogonal palette carries `Tokens`; every theme value carries none, which is what
// makes "no `[ui] mermaid_theme` value can reach a single one of those branches" structural.
assert!(theme::KONOMA.tokens.is_some());
for t in theme::ALL {
assert!(
t.tokens.is_none(),
"{}: a mermaid_theme palette must carry no drawing tokens",
t.name
);
}
}
/// A theme changes colours and nothing else.
///
/// Structurally guaranteed here — [`lay_out`] never sees a theme — but worth a test anyway,
/// because the bug it guards against did happen: when each theme measured with its own font, the
/// label boxes changed size per theme and an edge took a detour ring (reported from a real
/// terminal on 2026-07-17; §4-3). The comparison strips every `fill`/`stroke` colour and keeps
/// the rest, so a palette that quietly moved a coordinate cannot pass.
#[test]
fn themes_change_colours_but_never_geometry() {
let src = "flowchart TD\n A[Start] -->|go| B{Ready?}\n B --> C((end))";
let geometry_of = |s: &str| {
s.lines()
.map(|l| {
l.split_whitespace()
.filter(|w| !w.starts_with("fill=") && !w.starts_with("stroke=\""))
.collect::<Vec<_>>()
.join(" ")
})
.collect::<Vec<_>>()
.join("\n")
};
let base = geometry_of(&render(src, "dark").expect("renders"));
for name in ["light", "classic", "forest", "neutral"] {
assert_eq!(
base,
geometry_of(&render(src, name).expect("renders")),
"theme {name} moved something"
);
}
}
// ---------------------------------------------------------------------------------------------
// 7. Degrading rather than lying (§6)
// ---------------------------------------------------------------------------------------------
/// A diagram of another kind must not be drawn. The crate konoma ships turns `venn-beta` into
/// three boxes labelled "venn", "beta" and "sets" — a picture of something nobody wrote.
#[test]
fn another_diagram_kind_is_refused() {
assert!(matches!(
render("venn-beta\n sets: [a, b]", "dark"),
Err(RenderError::Parse(_))
));
assert!(matches!(
render("sequenceDiagram\n A->>B: hi", "dark"),
Err(RenderError::Parse(_))
));
}
/// A header with no body is not a diagram either. The current crate answers `graph TD` with a
/// 16x16 transparent SVG that gets stretched to full width.
#[test]
fn a_flowchart_with_no_nodes_is_refused() {
assert!(matches!(
render("graph TD", "dark"),
Err(RenderError::Parse(_))
));
}
/// A block is a frame, not a box: it is drawn, but it is not a node and it holds no label of its
/// own beyond the title. Its members stay ordinary nodes with ordinary edges.
#[test]
fn a_block_is_a_frame_and_not_a_node() {
let d =
laid_out("flowchart TD\n subgraph one [Group]\n A --> B\n end\n B --> C\n C --> A");
assert_eq!(d.nodes.len(), 3, "every member is still drawn");
assert_eq!(d.edges.len(), 3);
assert!(d.node("one").is_none(), "the block is not a node");
let frame = d.cluster("one").expect("the block is a frame");
assert_eq!(frame.title.lines, vec!["Group".to_string()]);
assert_eq!(frame.parent, None);
assert_eq!(frame.depth, 0);
}
/// An edge that names a block is drawn, and it points at the frame.
///
/// Stage 1c dropped it: the parser removes a subgraph id from the node list, so there was no
/// shape to attach the line to. Stage 1d re-anchors it onto a member for the layout and cuts it
/// back to the frame for the drawing.
#[test]
fn an_edge_can_name_a_block() {
let d = laid_out(
"flowchart TD\n subgraph one [Group]\n A --> B\n end\n one --> C\n D --> one",
);
assert!(d.node("one").is_none(), "the block is still not a node");
let named: Vec<&PlacedEdge> = d
.edges
.iter()
.filter(|e| e.from == "one" || e.to == "one")
.collect();
assert_eq!(named.len(), 2, "both edges onto the block survive");
for e in named {
assert!(e.points.len() >= 2, "{} -> {} has a line", e.from, e.to);
}
}
/// A block that holds no node at all is not drawn, and an edge that names it is dropped.
///
/// dagre gives a parent its rectangle through the border nodes it hangs off its children; a
/// parent with no children never gets any, and reading a box back from it would produce a frame
/// at the origin with no size. Dropping it is the honest answer.
#[test]
fn an_empty_block_is_not_drawn() {
let d = laid_out("flowchart TD\n subgraph hollow [Nothing]\n end\n A --> B\n hollow --> A");
assert!(d.clusters.is_empty(), "no frame for an empty block");
assert_eq!(d.edges.len(), 1, "the edge that named it is dropped");
assert_eq!(d.nodes.len(), 2);
}
/// A `direction` inside a block is read by the parser and **deliberately not applied**.
///
/// See [`super::lay_out`]'s note: dagre has one `rankdir` per layout, honouring a per-block one
/// means laying that block out in a graph of its own, and that is the change mermaid shipped in
/// 11.16.0 and took back in 11.17.0 because the arrows *between* blocks broke. Pinning it as a
/// test rather than as a comment means a future stage that changes its mind has to say so here.
#[test]
fn a_block_direction_does_not_move_anything() {
let with = laid_out(
"flowchart LR\n subgraph one [Steps]\n direction TB\n A --> B\n end\n B --> C",
);
let without = laid_out("flowchart LR\n subgraph one [Steps]\n A --> B\n end\n B --> C");
assert_eq!(with.nodes, without.nodes);
assert_eq!(with.clusters, without.clusters);
}
/// Errors carry the parser's reason. §8 notes the current crate throws these away, losing
/// messages as useful as "unknown participant 'API' at line 3".
#[test]
fn errors_say_what_was_wrong() {
let e = render("venn-beta", "dark").unwrap_err();
assert!(
e.to_string().contains("venn-beta"),
"the message should name what it found: {e}"
);
}
// ---------------------------------------------------------------------------------------------
// 8. Goldens
// ---------------------------------------------------------------------------------------------
/// The regression net over the whole corpus, **through [`render`]** — the function stage 1e will
/// wire into production, not a stand-in for it (§6, after konoma was once caught pinning a golden
/// on a function nothing called).
///
/// Numeric attribute values are masked; see the module docs for why (every coordinate descends
/// from the system font, so a byte-exact end-to-end golden would be a golden of this machine).
/// What is pinned is everything else: which elements, in what order, with which colours, which
/// path commands, and which text.
#[test]
fn corpus_golden() {
if !text_metrics::fonts_available() {
return;
}
let mut out = String::new();
for (name, src) in CORPUS {
out.push_str(&format!("=== {name} ===\n"));
out.push_str(&mask_numbers(&render(src, "dark").expect("renders")));
out.push('\n');
}
assert_snapshot("mermaid_render", &out);
}
/// A diagram assembled by hand, so **no font is involved and every number is pinned exactly**.
///
/// This is the other half of the golden: the corpus golden pins structure over real sources, this
/// one pins arithmetic — number formatting, the outline paths of all fifteen shapes, the curve,
/// the arrow heads, the dash patterns and the label patch.
#[test]
fn emit_golden() {
let d = synthetic_diagram();
let mut out = String::new();
// The five `[ui] mermaid_theme` palettes, spelled out rather than `theme::EVERY_PALETTE`:
// `theme::KONOMA` is reached only through `konoma-orthogonal`, whose own drawing §10-2 forbids
// putting in this file at all (the golden is the splines byte stream and must never move).
// Its emission is pinned by `konoma_orthogonal_draws_the_design_reference_look` instead.
for t in theme::ALL {
out.push_str(&format!("=== {} ===\n", t.name));
out.push_str(&super::svg::emit(&d, t));
out.push('\n');
}
assert_snapshot("mermaid_emit", &out);
}
/// One node of every shape and one edge of every stroke/arrow spelling, at coordinates chosen by
/// hand. Nothing here is measured, so it renders identically on every machine.
fn synthetic_diagram() -> Diagram {
let label = |text: &str, w: f64| Label {
lines: text.split('\n').map(str::to_string).collect(),
width: w,
height: text.split('\n').count() as f64 * super::labels::line_height(),
line_pitch: super::labels::line_height(),
font_size: crate::preview::mermaid::text_metrics::FONT_SIZE as f64,
};
let shapes_in_order = [
Shape::Rect,
Shape::RoundedRect,
Shape::Stadium,
Shape::Subroutine,
Shape::Cylinder,
Shape::Circle,
Shape::DoubleCircle,
Shape::Diamond,
Shape::Hexagon,
Shape::Odd,
Shape::Trapezoid,
Shape::InvTrapezoid,
Shape::LeanRight,
Shape::LeanLeft,
Shape::Text,
];
let mut nodes = Vec::new();
for (i, shape) in shapes_in_order.into_iter().enumerate() {
let text = if i == 0 { "two\nlines" } else { "label" };
let l = label(text, 40.0);
let size = flow_size(shape, Size::new(l.width, l.height));
nodes.push(PlacedNode {
id: format!("n{i}"),
shape: Glyph::Flow(shape),
center: Point::new(
120.0 + (i % 5) as f64 * 200.0,
80.0 + (i / 5) as f64 * 160.0,
),
size,
label: l,
panel: None,
series: None,
mark: None,
style: None,
});
}
let arrows = [
(Arrow::Point, Stroke::Normal),
(Arrow::None, Stroke::Normal),
(Arrow::Cross, Stroke::Dotted),
(Arrow::Circle, Stroke::Thick),
(Arrow::DoublePoint, Stroke::Normal),
(Arrow::DoubleCross, Stroke::Normal),
(Arrow::DoubleCircle, Stroke::Normal),
(Arrow::Invalid, Stroke::Invalid),
(Arrow::Point, Stroke::Invisible),
];
let mut edges = Vec::new();
for (i, (arrow, stroke)) in arrows.into_iter().enumerate() {
let y = 420.0 + i as f64 * 30.0;
let points = vec![
Point::new(60.0, y),
Point::new(200.0, y),
Point::new(200.0, y + 20.0),
Point::new(380.0, y + 20.0),
];
let l = label("via", 20.0);
edges.push(PlacedEdge {
from: format!("n{i}"),
to: format!("n{}", i + 1),
label: (i % 2 == 0).then(|| super::PlacedEdgeLabel {
center: edges::arc_midpoint(&points).expect("midpoint"),
size: Size::new(
l.width + super::LABEL_PAD_X * 2.0,
l.height + super::LABEL_PAD_Y * 2.0,
),
label: l,
}),
points,
gaps: Vec::new(),
tip_start: super::Tip::of_arrow(arrow).0,
tip_end: super::Tip::of_arrow(arrow).1,
stroke,
start_label: None,
end_label: None,
badge: None,
series: None,
straight: false,
overlay: false,
style: None,
curve: Curve::Basis,
tip_matches_line: false,
});
}
// Two frames, one inside the other, at coordinates chosen by hand: the outer one titled on
// two lines (the case that makes a frame grow) and the inner one untitled (the case that
// emits a rect and no text at all).
let clusters = vec![
PlacedCluster {
id: "outer".to_string(),
title: label("Outer frame\nwith two lines", 130.0),
center: Point::new(300.0, 620.0),
size: Size::new(360.0, 160.0),
parent: None,
depth: 0,
dashed: false,
filled: true,
sections: Vec::new(),
title_strip: false,
},
PlacedCluster {
id: "inner".to_string(),
title: label("", 0.0),
center: Point::new(320.0, 645.0),
size: Size::new(200.0, 90.0),
parent: Some("outer".to_string()),
depth: 1,
dashed: false,
filled: true,
sections: Vec::new(),
title_strip: false,
},
];
Diagram {
width: 1040.0,
height: 720.0,
nodes,
edges,
clusters,
lifelines: Vec::new(),
}
}
/// The number formatter, which every coordinate goes through. Three decimals, no trailing zeros,
/// and no `-0` (which is a legal float and an ugly attribute).
#[test]
fn numbers_are_written_the_same_way_every_time() {
assert_eq!(num(12.0), "12");
assert_eq!(num(12.5), "12.5");
assert_eq!(num(1.0 / 3.0), "0.333");
assert_eq!(num(-0.0001), "0");
assert_eq!(num(-12.25), "-12.25");
}
/// Text that would otherwise break the document is escaped, in both content and attributes.
#[test]
fn label_text_is_escaped() {
let svg = super::svg::escape("a < b & c > \"d\"");
assert_eq!(svg, "a < b & c > "d"");
if text_metrics::fonts_available() {
let out = render(
"flowchart TD\n A[\"a < b\"] --> B[\"x & y\"]",
"dark",
)
.expect("renders");
assert!(!out.contains("a < b"), "a raw < would break the document");
assert!(usvg::Tree::from_data(
out.as_bytes(),
&usvg::Options {
fontdb: shared_fontdb(),
..usvg::Options::default()
}
)
.is_ok());
}
}
/// Sources chosen to be awkward rather than realistic. konoma's rule is that the renderer runs on
/// a worker thread wrapped in `catch_unwind` (§1) — which is a safety net, not a licence — so
/// each of these has to come back with a diagram or an error, never a panic and never a diagram
/// with a NaN in it.
#[test]
fn awkward_sources_produce_a_diagram_or_an_error_and_never_a_panic() {
if !text_metrics::fonts_available() {
return;
}
let mut wide = String::from("flowchart LR\n");
for i in 0..120 {
wide.push_str(&format!(" n{i} --> n{}\n", i + 1));
}
wide.push_str(" n0 --> n120\n n120 --> n0\n");
// Twelve blocks, each inside the last. mermaid's own `adjustClustersAndEdges` gives up past a
// depth of ten; konoma's tree walk is bounded by the number of blocks instead, so this asks
// whether that bound is really there.
let mut deep = String::from("flowchart TD\n");
for i in 0..12 {
deep.push_str(&format!(" subgraph s{i} [Level {i}]\n"));
}
deep.push_str(" A --> B\n");
for _ in 0..12 {
deep.push_str(" end\n");
}
deep.push_str(" s0 --> C\n C --> s11\n");
let cases: &[&str] = &[
"",
" \n\n ",
"flowchart TD",
"flowchart TD\n A[\"\"]",
"flowchart TD\n A[\" \"] --> B[\"\"]",
"flowchart TD\n A -->|| B",
"flowchart TD\n A --> A",
"flowchart LR\n A[\"<script>&\"] --> B[\"a > b\"]",
"flowchart TD\n A[\"一\"] --> B[\"🎉\"]",
"flowchart TD\n %% only a comment\n A --> B",
"flowchart TD\n classDef hot fill:#f9f\n A:::hot --> B",
"flowchart TD\n A@{ shape: cyl, label: \"store\" } --> B",
// Blocks, in the shapes a person would not write on purpose.
"flowchart TD\n subgraph one\n end\n A --> B",
"flowchart TD\n subgraph one\n end\n one --> one",
"flowchart TD\n subgraph one [Group]\n A --> B\n end\n one --> A",
"flowchart TD\n subgraph one [Group]\n A --> B\n end\n one --> one",
"flowchart LR\n subgraph one\n subgraph two\n subgraph three\n A\n end\n end\n end\n one --> three",
"flowchart TD\n subgraph one [\"\"]\n A\n end\n A --> B",
"flowchart TD\n A --> one\n subgraph one [Declared after the edge]\n B --> C\n end",
&deep,
&wide,
];
for src in cases {
match render(src, "dark") {
Err(_) => {}
Ok(svg) => {
assert!(!svg.contains("NaN"), "NaN reached the document for {src:?}");
assert!(
!svg.contains("inf"),
"an infinity reached the document for {src:?}"
);
let d = laid_out(src);
assert!(
d.width.is_finite() && d.height.is_finite() && d.width > 0.0 && d.height > 0.0,
"{src:?}: {}x{} is not a drawable size",
num(d.width),
num(d.height)
);
assert!(
crate::preview::svg::rasterize_bytes(svg.as_bytes(), FsPath::new("m.svg"), 300)
.is_some(),
"{src:?}: the output did not rasterise"
);
}
}
}
}
// ---------------------------------------------------------------------------------------------
// 9. `classDef` / `class` / `:::` / `style` / `linkStyle` (docs/STATUS.md, 2026-08-28 regression)
// ---------------------------------------------------------------------------------------------
//
// The bug this section pins: `flowchart/parser.rs` always kept `class_defs` and `link_styles` —
// only so `classDef hot fill:#f9f` could not become a phantom node (§2-3) — and nothing
// downstream ever read what they said. `mask_numbers` (this file's module docs) hides
// `stroke-width`/`stroke-dasharray` but **not** `fill`/`stroke`, so a colour regression here would
// have shown up in `corpus_golden` if the corpus had a case for it; it did not (`CORPUS` has no
// `classDef` source), which is exactly how this shipped unnoticed. These tests read
// [`PlacedNode::style`]/[`PlacedEdge::style`] directly rather than relying on a golden, so a future
// regression fails by name instead of by an unrelated-looking snapshot diff.
/// `classDef default` colours every node automatically, and must **not** leak onto an edge that
/// carries neither a `class` of its own nor any `linkStyle` — caught while regenerating the
/// corpus golden for this section: [`super::style::cascade_edge`] used to start from
/// [`super::style::cascade`], which begins every element at `classDef default`, and an edge is
/// not a node.
#[test]
fn classdef_default_colours_nodes_but_not_an_untouched_edge() {
let d = laid_out("flowchart TD\n classDef default fill:#223,stroke:#556\n A --> B");
assert_eq!(
d.node("A")
.unwrap()
.style
.as_ref()
.unwrap()
.stroke
.as_deref(),
Some("#556"),
"classDef default must still colour every node"
);
assert!(
d.edges[0].style.is_none(),
"the edge names neither a class nor a linkStyle, so classDef default must not reach it"
);
let svg = render(
"flowchart TD\n classDef default fill:#223,stroke:#556\n A --> B",
"dark",
)
.expect("renders");
assert_eq!(
svg.matches("stroke=\"#556\"").count(),
2,
"exactly the two node rects (A and B) may carry classDef default's stroke, never the edge's path: {svg}"
);
assert!(
svg.contains(&format!("stroke=\"{}\"", theme::DARK.line)),
"the edge's path must still draw in the theme's own line colour: {svg}"
);
}
/// `classDef` + `class` colours the node it names, and leaves every other node at the theme's own
/// colour.
#[test]
fn classdef_and_class_colour_the_node_they_name() {
let d =
laid_out("flowchart TD\n classDef hot fill:#f9f,stroke:#a00\n A --> B\n class A hot");
let a = d
.node("A")
.expect("A exists")
.style
.as_ref()
.expect("A has a style");
assert_eq!(a.fill.as_deref(), Some("#f9f"));
assert_eq!(a.stroke.as_deref(), Some("#a00"));
assert!(
d.node("B").expect("B exists").style.is_none(),
"class hot named only A, so B must keep the theme's own colour"
);
let svg = render(
"flowchart TD\n classDef hot fill:#f9f,stroke:#a00\n A --> B\n class A hot",
"dark",
)
.expect("renders");
assert!(
svg.contains("fill=\"#f9f\""),
"the fill reaches the SVG: {svg}"
);
}
/// `:::hot` at the declaration does what a separate `class` statement does.
#[test]
fn triple_colon_is_the_same_as_a_class_statement() {
let d = laid_out("flowchart TD\n classDef hot fill:#f9f\n A:::hot --> B");
let a = d
.node("A")
.expect("A exists")
.style
.as_ref()
.expect("A has a style");
assert_eq!(a.fill.as_deref(), Some("#f9f"));
assert!(d.node("B").expect("B exists").style.is_none());
}
/// A node's own `style` statement is the last step of the cascade, so it wins over a `classDef`
/// the node also carries — D2's "後のものが前を上書きする".
#[test]
fn a_nodes_own_style_wins_over_its_classdef() {
let d =
laid_out("flowchart TD\n classDef hot fill:#f9f\n A:::hot --> B\n style A fill:#00ff00");
let a = d
.node("A")
.expect("A exists")
.style
.as_ref()
.expect("A has a style");
assert_eq!(
a.fill.as_deref(),
Some("#00ff00"),
"the node's own `style` statement must be the final word, not the classDef"
);
}
/// `linkStyle <idx>` touches only the edge at that index into [`Flowchart::edges`] — proof the
/// index-to-edge mapping is right, not just that *an* edge got styled.
#[test]
fn link_style_by_index_touches_only_that_edge() {
let d = laid_out("flowchart TD\n A --> B\n B --> C\n C --> D\n linkStyle 1 stroke:#1f6feb");
assert_eq!(d.edges.len(), 3, "three edges: A->B, B->C, C->D");
assert!(d.edges[0].style.is_none(), "A->B (index 0) is untouched");
assert_eq!(
d.edges[1]
.style
.as_ref()
.expect("B->C (index 1) has a style")
.stroke
.as_deref(),
Some("#1f6feb")
);
assert!(d.edges[2].style.is_none(), "C->D (index 2) is untouched");
}
/// `linkStyle 0,1,2 stroke:#1f6feb` — the user's own reported shape
/// (`~/work/Ergora/doc/spec/05-system-architecture.md`), where several indices share one
/// declaration. Every named edge gets it and the edge left out does not.
#[test]
fn link_style_with_multiple_indices_reaches_every_named_edge() {
let d = laid_out(
"flowchart TD\n A --> B\n B --> C\n C --> D\n D --> E\n \
linkStyle 0,1,2 stroke:#1f6feb",
);
assert_eq!(d.edges.len(), 4);
for i in 0..3 {
assert_eq!(
d.edges[i]
.style
.as_ref()
.unwrap_or_else(|| panic!("edge {i} has a style"))
.stroke
.as_deref(),
Some("#1f6feb"),
"edge {i} is named by `linkStyle 0,1,2`"
);
}
assert!(
d.edges[3].style.is_none(),
"edge 3 (D->E) was not named, and must be untouched"
);
}
/// `linkStyle default` colours every edge, and a specific index still overrides it — the fixed
/// pipeline order [`super::style::cascade_edge`]'s docs describe, independent of which the source
/// physically wrote first.
#[test]
fn link_style_default_colours_every_edge_and_an_index_still_overrides_it() {
let d = laid_out(
"flowchart TD\n A --> B\n B --> C\n linkStyle 0 stroke:#e11\n \
linkStyle default stroke:#39d",
);
assert_eq!(
d.edges[0].style.as_ref().unwrap().stroke.as_deref(),
Some("#e11"),
"edge 0's own index is more specific than `default`, even written first"
);
assert_eq!(
d.edges[1].style.as_ref().unwrap().stroke.as_deref(),
Some("#39d"),
"edge 1 has no index of its own, so `default` reaches it"
);
}
/// `stroke-width` is one of [`mask_numbers`]' masked attributes, so the golden cannot see whether
/// it actually reached the SVG — this asserts on the unmasked string directly.
#[test]
fn link_style_stroke_width_reaches_the_unmasked_svg() {
let svg = render(
"flowchart TD\n A --> B\n linkStyle 0 stroke-width:4px",
"dark",
)
.expect("renders");
assert!(
svg.contains("stroke-width=\"4\""),
"the declared width must reach the path's own attribute, unmasked: {svg}"
);
}
// --- the four tests above this line all read `Diagram`/`PlacedEdge::style` — the *model* the
// cascade resolves into. Every one of them is blind to a defect in the last step, `svg.rs`
// applying that field when it writes the `<path>` element: the regression this whole section
// exists for was reported *from that exact step* (`linkStyle` colours that reached `PlacedEdge`
// correctly and never reached the SVG the terminal draws). The tests below read the emitted
// string instead of the model, so a defect confined to `svg::emit_edge` — the model right, the
// drawing wrong — fails one of these rather than passing every model-level test in the file.
/// `linkStyle <idx> stroke:#…` reaches the one path element for that edge, in the raw SVG text,
/// and the other edges' paths keep the theme's own line colour.
#[test]
fn link_style_single_index_stroke_reaches_the_svg_and_only_that_edges_path() {
let svg = render(
"flowchart TD\n A --> B\n B --> C\n C --> D\n linkStyle 1 stroke:#1f6feb",
"dark",
)
.expect("renders");
assert_eq!(
svg.matches("stroke=\"#1f6feb\"").count(),
1,
"exactly one edge (index 1) was named: {svg}"
);
assert_eq!(
svg.matches(&format!("stroke=\"{}\"", theme::DARK.line))
.count(),
2,
"the other two edges must still draw in the theme's own line colour: {svg}"
);
}
/// `linkStyle 0,1,2 stroke:#…` — several indices sharing one declaration, the user's own reported
/// shape (`~/work/Ergora/doc/spec/05-system-architecture.md`) — reaches every named edge's path in
/// the raw SVG text, and the edge left out does not get it.
#[test]
fn link_style_multiple_indices_stroke_reaches_every_named_edges_path() {
let svg = render(
"flowchart TD\n A --> B\n B --> C\n C --> D\n D --> E\n \
linkStyle 0,1,2 stroke:#1f6feb",
"dark",
)
.expect("renders");
assert_eq!(
svg.matches("stroke=\"#1f6feb\"").count(),
3,
"three edges (0, 1, 2) were named: {svg}"
);
assert_eq!(
svg.matches(&format!("stroke=\"{}\"", theme::DARK.line))
.count(),
1,
"the fourth edge (D->E) was not named and must keep the theme's line colour: {svg}"
);
}
/// `linkStyle default` colours every edge's path in the raw SVG text, and an indexed `linkStyle`
/// still overrides it there too — the same fixed pipeline order the model-level
/// [`link_style_default_colours_every_edge_and_an_index_still_overrides_it`] states, checked at
/// the one step that test cannot see.
#[test]
fn link_style_default_then_an_index_reach_the_svg_as_two_distinct_colours() {
let svg = render(
"flowchart TD\n A --> B\n B --> C\n linkStyle 0 stroke:#e11\n \
linkStyle default stroke:#39d",
"dark",
)
.expect("renders");
assert_eq!(
svg.matches("stroke=\"#e11\"").count(),
1,
"edge 0's own index must win over `default`, even written first: {svg}"
);
assert_eq!(
svg.matches("stroke=\"#39d\"").count(),
1,
"edge 1 has no index of its own, so `default` must reach its path: {svg}"
);
}
/// An unparsable colour is dropped, not substituted with black — [`super::style::paint`]'s whole
/// reason for existing (`UiConfig::math_color`'s "blank equation" precedent). The node must still
/// draw, in the theme's own colour, and the document must still be valid SVG.
#[test]
fn an_invalid_color_falls_back_to_the_theme_instead_of_black() {
let d = laid_out("flowchart TD\n classDef bad fill:notacolor\n A:::bad --> B");
assert!(
d.node("A").unwrap().style.is_none(),
"the only declared field failed to validate, so there is nothing to override with"
);
let svg = render(
"flowchart TD\n classDef bad fill:notacolor\n A:::bad --> B",
"dark",
)
.expect("renders");
assert!(
svg.contains(theme::DARK.node_fill),
"A must draw in the theme's node colour, not vanish or turn black: {svg}"
);
assert!(
!svg.contains("notacolor"),
"the bad literal must never reach the SVG document"
);
// `tree_of` itself `.expect()`s a successful parse, so simply calling it is the assertion:
// the document is still valid SVG usvg can read.
tree_of(&svg);
}
// ---------------------------------------------------------------------------------------------
// 10. `curve` (`[ui] mermaid_curve` / `linkStyle ... interpolate`)
// ---------------------------------------------------------------------------------------------
//
// mermaid's most-requested flowchart feature is a straight/right-angle line instead of the
// default spline (mermaid-js#2817, 129 reactions; mermaid-js#2549, 75 reactions; both open 4+
// years). The unconditional requirement this section exists to pin: `render_curve(..., "basis")`
// — and so `render` itself, which is defined as exactly that call — must draw byte-for-byte what
// it drew before `curve` existed. `corpus_golden` staying green already implies this; these tests
// state the reason directly, the way §9 states its own bug by name instead of by an
// unrelated-looking snapshot diff.
/// D5's invariant, stated directly: the default curve changes nothing. `render` is `render_curve`
/// called with `"basis"` (`mod.rs`'s own definition), so this is really pinning that the
/// delegation stays what it is — but a future edit could still break it by, say, giving `render`
/// its own copy of the pipeline that drifts from `render_curve`'s.
#[test]
fn basis_curve_is_byte_identical_to_render() {
for (name, src) in CORPUS {
let via_curve =
render_curve(src, "dark", "basis").unwrap_or_else(|e| panic!("{name}: {e}"));
let via_render = render(src, "dark").unwrap_or_else(|e| panic!("{name}: {e}"));
assert_eq!(
via_curve, via_render,
"{name}: render_curve(..., \"basis\") must match render() exactly"
);
}
}
/// `Curve::Basis` still rounds right-angle corners off (`edges::fix_corners`) — today's look,
/// unchanged. Segment lengths are past `fix_corners`' short-corner guard (`CORNER_RADIUS`'s own
/// module docs use 10px as the threshold), so the corner really is rounded, not left alone by a
/// guard this test failed to clear.
#[test]
fn basis_curve_still_rounds_corners() {
let raw = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 40.0),
Point::new(40.0, 40.0),
];
let edge = bent_edge(raw.clone(), Curve::Basis);
assert_eq!(edge.drawn_points(), edges::fix_corners(&raw));
assert_ne!(
edge.drawn_points(),
raw,
"a real right angle must actually be rounded under Curve::Basis"
);
}
/// `Curve::Linear` still runs `fix_corners`, the same as every curve but `Rounded`
/// (`Curve::rounds_corners`'s own doc has the versioned evidence). **This test used to assert the
/// opposite** — that `linear` kept a sharp right angle — on the reasoning that `linear`/`step*`
/// are chosen *because* they draw a sharp angle, so rounding one off would undo the shape asked
/// for. That reasoning was never checked against upstream, and it was wrong: `mermaid@11.4.1` and
/// `mermaid@11.12.0` (both released versions) call `fixCorners` unconditionally in `edges.js`, no
/// curve-type check at all, so a real `linear` flowchart on GitHub has this exact corner softened
/// too. This crate's acceptance test is "the same source reads the same picture GitHub draws"
/// (this session's own brief), so the fixed expectation is the one that matches that picture, not
/// the one that looked most consistent with `linear`'s own name.
#[test]
fn linear_curve_also_rounds_corners() {
let raw = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 40.0),
Point::new(40.0, 40.0),
];
let edge = bent_edge(raw.clone(), Curve::Linear);
assert_eq!(
edge.drawn_points(),
edges::fix_corners(&raw),
"Curve::Linear must run fix_corners, matching every released mermaid version"
);
assert_ne!(
edge.drawn_points(),
raw,
"a real right angle must actually be rounded under Curve::Linear too"
);
// `Curve::Linear.path` itself is still an unmodified `polyline_path` — straight segments
// through whatever points it is given. What changed is which points it is given: the
// fix_corners-rounded ones (`drawn_points`), not the raw waypoints. `polyline_path` drawing a
// straight line between two rounded-corner points is exactly how `fixCorners` + `curveLinear`
// reads upstream too — the corner becomes a short straight chamfer, not a smooth arc.
assert_eq!(
Curve::Linear.path(&edge.drawn_points()),
edges::polyline_path(&edge.drawn_points())
);
}
/// `Curve::Step` also runs `fix_corners` — same evidence, same fix as `Curve::Linear`'s own test
/// just above. Checked separately because `step`'s own shape (an explicit right-angle transition
/// mid-segment) makes it easy to assume, wrongly, that `fixCorners` would be redundant on it; it
/// is not — `fixCorners` acts on the edge's *waypoints*, before `step_path` ever sees them, so a
/// real right-angle waypoint (not `step`'s own synthetic transition point) is softened exactly
/// like it is for every other non-`Rounded` curve.
#[test]
fn step_curve_also_rounds_corners() {
let raw = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 40.0),
Point::new(40.0, 40.0),
];
let edge = bent_edge(raw.clone(), Curve::Step);
assert_eq!(
edge.drawn_points(),
edges::fix_corners(&raw),
"Curve::Step must run fix_corners, matching every released mermaid version"
);
assert_ne!(edge.drawn_points(), raw);
}
/// `Curve::Rounded` is the one curve `PlacedEdge::drawn_points` does **not** run `fix_corners`
/// for — it rounds every corner itself, at its own radius (`rounded_path`), so pre-rounding would
/// round the same corner twice. The regression this guards: a mutation that made `Rounded` *also*
/// run `fix_corners` (double-rounding) must be caught here, not just inferred from
/// `Curve::rounds_corners`'s own boolean.
#[test]
fn rounded_curve_does_not_also_run_fix_corners() {
let raw = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 40.0),
Point::new(40.0, 40.0),
];
let edge = bent_edge(raw.clone(), Curve::Rounded);
assert_eq!(
edge.drawn_points(),
raw,
"Curve::Rounded must not run fix_corners — it rounds corners itself"
);
}
/// The three step variants draw three different shapes for the same waypoints — the regression
/// guard against copy-pasting one branch over another. Values are worked out from d3-shape's own
/// `Step` class (`edges.rs`'s `step_path` docs): `stepBefore` goes vertical first, `stepAfter`
/// goes horizontal first, `step` splits at the midpoint.
#[test]
fn step_variants_differ_from_each_other_and_match_d3() {
let pts = vec![Point::new(0.0, 0.0), Point::new(40.0, 60.0)];
let step = Curve::Step.path(&pts);
let before = Curve::StepBefore.path(&pts);
let after = Curve::StepAfter.path(&pts);
assert_ne!(step, before, "step and stepBefore must draw differently");
assert_ne!(step, after, "step and stepAfter must draw differently");
assert_ne!(
before, after,
"stepBefore and stepAfter must draw differently"
);
let m = |x: f64, y: f64| format!("M{},{}", num(x), num(y));
let l = |x: f64, y: f64| format!("L{},{}", num(x), num(y));
assert_eq!(
before,
format!("{}{}{}", m(0.0, 0.0), l(0.0, 60.0), l(40.0, 60.0)),
"stepBefore: vertical leg first, at the segment's starting x"
);
assert_eq!(
after,
format!("{}{}{}", m(0.0, 0.0), l(40.0, 0.0), l(40.0, 60.0)),
"stepAfter: horizontal leg first, at the segment's ending x"
);
assert_eq!(
step,
format!(
"{}{}{}{}",
m(0.0, 0.0),
l(20.0, 0.0),
l(20.0, 60.0),
l(40.0, 60.0)
),
"step: the transition sits at the segment's midpoint x, and the line still reaches p1"
);
}
/// `linkStyle <n> interpolate <curve>` reaches exactly the edge it names, and no other — the
/// wiring `flowchart/model.rs` used to say konoma does not have (§2-5, now implemented).
#[test]
fn link_style_interpolate_affects_only_that_edge() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n C --> D\n linkStyle 0 interpolate linear",
"basis",
);
assert_eq!(d.edges[0].curve, Curve::Linear);
assert_eq!(d.edges[1].curve, Curve::Basis);
}
/// An edge's own `linkStyle interpolate` wins over the chart-wide `[ui] mermaid_curve` default —
/// the priority order D4 requires, stated as the strongest case: the two disagree outright.
#[test]
fn link_style_interpolate_overrides_the_chart_wide_default() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n linkStyle 0 interpolate linear",
"step",
);
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"the edge's own interpolate must win over ui.mermaid_curve"
);
}
/// `linkStyle default interpolate` sets the chart-wide default for every edge that names no
/// index of its own, exactly the way `style::cascade_edge` already treats `linkStyle default`
/// styles — and an indexed `linkStyle` still wins over it, the same cascade order.
#[test]
fn link_style_default_interpolate_applies_unless_an_index_overrides_it() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n C --> D\n linkStyle default interpolate linear\n \
linkStyle 1 interpolate step",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"linkStyle default interpolate applies to an edge with no index override"
);
assert_eq!(
d.edges[1].curve,
Curve::Step,
"linkStyle 1's own interpolate must still win over linkStyle default"
);
}
/// An unrecognised curve name falls back to `Curve::Basis` rather than erroring, both directly
/// through `Curve::parse` and through the whole config → render pipeline. Never crashes.
///
/// All 13 of mermaid's own `flowchart.curve` values are implemented as of this test (see the
/// "eight newly implemented curves" section below), so "a real d3 curve this crate does not
/// implement" is no longer an example this test can give — `curveBasisClosed` stands in instead:
/// a real d3-shape curve name, just not one mermaid's `flowchart.curve` schema ever accepts.
#[test]
fn unknown_curve_falls_back_to_basis_without_crashing() {
assert_eq!(
Curve::parse("basisClosed"),
Curve::Basis,
"a real d3-shape curve, but not one of mermaid's flowchart.curve values"
);
assert_eq!(
Curve::parse("Basis"),
Curve::Basis,
"wrong case — Curve::parse is case-sensitive, matching mermaid's own spellings"
);
assert_eq!(
Curve::parse("nonsense"),
Curve::Basis,
"not a curve name at all"
);
assert_eq!(Curve::parse(""), Curve::Basis, "empty string");
let d = laid_out_curve("flowchart TD\n A --> B", "basisClosed");
assert_eq!(d.edges[0].curve, Curve::Basis);
let svg = render_curve("flowchart TD\n A --> B", "dark", "nonsense")
.expect("an unknown curve must still render, as Curve::Basis");
assert!(svg.contains("<svg"));
}
// ---------------------------------------------------------------------------------------------
// 10-b. The eight curves implemented after the five above: d3-shape's `natural`, `cardinal`,
// `catmullRom`, `monotoneX`, `monotoneY`, `bumpX`, `bumpY`, and mermaid's own `rounded`.
// ---------------------------------------------------------------------------------------------
//
// Every `_matches_d3` test below pins geometry generated by actually running the real npm
// `d3-shape` package (v3, the version mermaid itself depends on) through a small Node context
// object that records `moveTo`/`lineTo`/`bezierCurveTo` calls in exactly the string convention
// this module's own `push_move`/`push_line`/`push_bezier` use (comma inside a coordinate pair,
// space between pairs, three-decimal rounding via the same formula as `svg::num`) — not hand-
// derived, and not `curve_basis_matches_d3`'s approach of working the control-point algebra out
// by hand, because a spline family this size (five distinct state machines, one of them with an
// epsilon-gated weighting term) is exactly where hand arithmetic is most likely to be the thing
// that is wrong. The three point sets are chosen on purpose: `RIGHT_ANGLE` and `FOUR_POINT` have
// evenly-spaced waypoints, under which centripetal Catmull-Rom (`catmullRom`) and the classic
// Cardinal spline (`cardinal`) are mathematically the same curve — so `UNEVEN` (unequal segment
// lengths) is the set that actually exercises `catmullRom`'s own epsilon-gated weighting and
// tells the two apart; without it a `cardinal`/`catmullRom` copy-paste bug would pass silently.
//
// `VERTICAL`/`HORIZONTAL`/`DUPLICATE` exist because none of the three sets above ever has two
// consecutive points share a coordinate, and that is exactly the shape that broke `monotoneX` in
// production: `flowchart TD` is konoma's *default* direction, under which an ordinary vertical
// edge is three points with the same x — `slope3`'s `dx` is `0` for that pair, which upstream
// handles (its `Math.min` propagates the resulting `NaN` through to a `0` fallback) and this
// crate's first port of it did not (`js_min`'s own doc has the full mechanism). `VERTICAL` is
// exactly that shape; `HORIZONTAL` is its mirror (the case `monotoneY`'s reflected axis turns
// into the same failure); `DUPLICATE` is the more general version — two *identical* consecutive
// points, which is what an axis-aligned run degenerates to when dagre's own dedup does not catch
// it. All three were mechanically swept over every one of the 13 curves (not guessed at from the
// bug report) — `Curve::path` never emits `NaN`/`Infinity` for any of them, pinned separately by
// `no_curve_ever_emits_nan_or_infinite_coordinates` below.
const RIGHT_ANGLE: [(f64, f64); 3] = [(0.0, 0.0), (60.0, 0.0), (60.0, 60.0)];
const FOUR_POINT: [(f64, f64); 4] = [(0.0, 0.0), (40.0, 0.0), (40.0, 40.0), (80.0, 40.0)];
const UNEVEN: [(f64, f64); 4] = [(0.0, 0.0), (10.0, 0.0), (40.0, 30.0), (90.0, 35.0)];
/// Three collinear points sharing an x — an ordinary vertical edge under `flowchart TD`,
/// konoma's default direction. The exact shape that broke `monotoneX` in production.
const VERTICAL: [(f64, f64); 3] = [(100.0, 50.0), (100.0, 120.0), (100.0, 190.0)];
/// `VERTICAL`'s mirror — three collinear points sharing a y, the shape that breaks `monotoneY`'s
/// reflected axis the same way `VERTICAL` breaks `monotoneX`'s own.
const HORIZONTAL: [(f64, f64); 3] = [(50.0, 100.0), (120.0, 100.0), (190.0, 100.0)];
/// Two consecutive points at the exact same coordinate — the more general version of
/// `VERTICAL`/`HORIZONTAL`'s "a segment has zero length" degeneracy, on a diagonal run instead of
/// an axis-aligned one.
const DUPLICATE: [(f64, f64); 4] = [(0.0, 0.0), (40.0, 40.0), (40.0, 40.0), (80.0, 80.0)];
fn pts(raw: &[(f64, f64)]) -> Vec<Point> {
raw.iter().map(|&(x, y)| Point::new(x, y)).collect()
}
#[test]
fn curve_natural_matches_d3() {
assert_eq!(
edges::curve_natural_path(&pts(&RIGHT_ANGLE)),
"M0,0C25,-5 50,-10 60,0C70,10 65,35 60,60"
);
assert_eq!(
edges::curve_natural_path(&pts(&FOUR_POINT)),
"M0,0C17.778,-4.444 35.556,-8.889 40,0C44.444,8.889 35.556,31.111 40,40\
C44.444,48.889 62.222,44.444 80,40"
);
assert_eq!(
edges::curve_natural_path(&pts(&UNEVEN)),
"M0,0C2,-3.222 4,-6.444 10,0C16,6.444 26,22.556 40,30C54,37.444 72,36.222 90,35"
);
assert_eq!(
edges::curve_natural_path(&pts(&VERTICAL)),
"M100,50C100,73.333 100,96.667 100,120C100,143.333 100,166.667 100,190"
);
assert_eq!(
edges::curve_natural_path(&pts(&HORIZONTAL)),
"M50,100C73.333,100 96.667,100 120,100C143.333,100 166.667,100 190,100"
);
assert_eq!(
edges::curve_natural_path(&pts(&DUPLICATE)),
"M0,0C17.778,17.778 35.556,35.556 40,40C44.444,44.444 35.556,35.556 40,40\
C44.444,44.444 62.222,62.222 80,80"
);
// Two points are a line; one is a bare move; zero is empty — the shared degenerate cases.
assert_eq!(
edges::curve_natural_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0L60,0"
);
assert_eq!(edges::curve_natural_path(&pts(&RIGHT_ANGLE[..1])), "M0,0");
assert_eq!(edges::curve_natural_path(&[]), "");
}
#[test]
fn curve_cardinal_matches_d3() {
assert_eq!(
edges::curve_cardinal_path(&pts(&RIGHT_ANGLE)),
"M0,0C0,0 50,-10 60,0C70,10 60,60 60,60"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&FOUR_POINT)),
"M0,0C0,0 33.333,-6.667 40,0C46.667,6.667 33.333,33.333 40,40\
C46.667,46.667 80,40 80,40"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&UNEVEN)),
"M0,0C0,0 3.333,-5 10,0C16.667,5 26.667,24.167 40,30C53.333,35.833 90,35 90,35"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&VERTICAL)),
"M100,50C100,50 100,96.667 100,120C100,143.333 100,190 100,190"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&HORIZONTAL)),
"M50,100C50,100 96.667,100 120,100C143.333,100 190,100 190,100"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&DUPLICATE)),
"M0,0C0,0 33.333,33.333 40,40C46.667,46.667 33.333,33.333 40,40\
C46.667,46.667 80,80 80,80"
);
assert_eq!(
edges::curve_cardinal_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0L60,0"
);
assert_eq!(edges::curve_cardinal_path(&pts(&RIGHT_ANGLE[..1])), "M0,0");
assert_eq!(edges::curve_cardinal_path(&[]), "");
}
#[test]
fn curve_catmull_rom_matches_d3() {
assert_eq!(
edges::curve_catmull_rom_path(&pts(&RIGHT_ANGLE)),
"M0,0C0,0 50,-10 60,0C70,10 60,60 60,60"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&FOUR_POINT)),
"M0,0C0,0 33.333,-6.667 40,0C46.667,6.667 33.333,33.333 40,40\
C46.667,46.667 80,40 80,40"
);
// The one point set that actually tells `catmullRom` apart from `cardinal` — see this
// section's own module doc.
assert_eq!(
edges::curve_catmull_rom_path(&pts(&UNEVEN)),
"M0,0C0,0 6.169,-1.587 10,0C17.89,3.268 27.455,24.055 40,30C53.653,36.47 90,35 90,35"
);
assert_ne!(
edges::curve_catmull_rom_path(&pts(&UNEVEN)),
edges::curve_cardinal_path(&pts(&UNEVEN)),
"catmullRom and cardinal must differ once waypoints are unevenly spaced"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&VERTICAL)),
"M100,50C100,50 100,96.667 100,120C100,143.333 100,190 100,190"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&HORIZONTAL)),
"M50,100C50,100 96.667,100 120,100C143.333,100 190,100 190,100"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&DUPLICATE)),
"M0,0C0,0 40,40 40,40C40,40 40,40 40,40C40,40 80,80 80,80"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0L60,0"
);
assert_eq!(
edges::curve_catmull_rom_path(&pts(&RIGHT_ANGLE[..1])),
"M0,0"
);
assert_eq!(edges::curve_catmull_rom_path(&[]), "");
}
#[test]
fn curve_monotone_x_matches_d3() {
assert_eq!(
edges::curve_monotone_x_path(&pts(&RIGHT_ANGLE)),
"M0,0C20,0 40,0 60,0C60,0 60,60 60,60"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&FOUR_POINT)),
"M0,0C13.333,0 26.667,0 40,0C40,0 40,40 40,40C53.333,40 66.667,40 80,40"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&UNEVEN)),
"M0,0C3.333,0 6.667,0 10,0C20,0 30,28 40,30C56.667,33.333 73.333,34.167 90,35"
);
// The exact bug: three collinear points sharing an x (an ordinary vertical edge under
// `flowchart TD`, konoma's default direction) made `slope3`'s `p` become `NaN`
// (`Infinity * 0 - Infinity * 0`) — upstream's `Math.min` propagates that `NaN` through to a
// `0` fallback (a flat tangent), which is the finite, correct answer below. This crate's
// first port used `f64::min`, which *ignores* a `NaN` operand instead of propagating it
// (`js_min`'s own doc has the full mechanism), so `slope3` returned `Infinity` and the
// resulting bezier control points were `NaN` — an invalid SVG path whose line silently did
// not draw at all (found by rendering a real `curve: monotoneX` flowchart and looking at it).
assert_eq!(
edges::curve_monotone_x_path(&pts(&VERTICAL)),
"M100,50C100,50 100,120 100,120C100,120 100,190 100,190"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&HORIZONTAL)),
"M50,100C73.333,100 96.667,100 120,100C143.333,100 166.667,100 190,100"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&DUPLICATE)),
"M0,0C13.333,13.333 26.667,26.667 40,40C53.333,53.333 66.667,66.667 80,80"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0L60,0"
);
assert_eq!(
edges::curve_monotone_x_path(&pts(&RIGHT_ANGLE[..1])),
"M0,0"
);
assert_eq!(edges::curve_monotone_x_path(&[]), "");
}
#[test]
fn curve_monotone_y_matches_d3() {
assert_eq!(
edges::curve_monotone_y_path(&pts(&RIGHT_ANGLE)),
"M0,0C0,0 60,0 60,0C60,20 60,40 60,60"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&FOUR_POINT)),
"M0,0C0,0 40,0 40,0C40,13.333 40,26.667 40,40C40,40 80,40 80,40"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&UNEVEN)),
"M0,0C0,0 10,0 10,0C30,10 20,20 40,30C43.333,31.667 66.667,33.333 90,35"
);
assert_ne!(
edges::curve_monotone_x_path(&pts(&UNEVEN)),
edges::curve_monotone_y_path(&pts(&UNEVEN)),
"monotoneX and monotoneY must draw differently — the whole point of the reflected axis"
);
// `VERTICAL`'s mirror: `monotoneY`'s reflected axis hits the same degeneracy on a
// *horizontal* run instead of a vertical one — see `curve_monotone_x_matches_d3`'s own
// comment on the exact bug this pins the fix for.
assert_eq!(
edges::curve_monotone_y_path(&pts(&VERTICAL)),
"M100,50C100,73.333 100,96.667 100,120C100,143.333 100,166.667 100,190"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&HORIZONTAL)),
"M50,100C50,100 120,100 120,100C120,100 190,100 190,100"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&DUPLICATE)),
"M0,0C13.333,13.333 26.667,26.667 40,40C53.333,53.333 66.667,66.667 80,80"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0L60,0"
);
assert_eq!(
edges::curve_monotone_y_path(&pts(&RIGHT_ANGLE[..1])),
"M0,0"
);
assert_eq!(edges::curve_monotone_y_path(&[]), "");
}
#[test]
fn curve_bump_x_matches_d3() {
assert_eq!(
edges::curve_bump_x_path(&pts(&RIGHT_ANGLE)),
"M0,0C30,0 30,0 60,0C60,0 60,60 60,60"
);
assert_eq!(
edges::curve_bump_x_path(&pts(&FOUR_POINT)),
"M0,0C20,0 20,0 40,0C40,0 40,40 40,40C60,40 60,40 80,40"
);
assert_eq!(
edges::curve_bump_x_path(&pts(&UNEVEN)),
"M0,0C5,0 5,0 10,0C25,0 25,30 40,30C65,30 65,35 90,35"
);
// Unlike every other curve in this module, `bumpX` draws a curve — not a straight `L` — even
// between just two points: d3-shape's own `Bump.point` has no `case 2` that falls back to a
// line (`edges.rs`'s own `curve_bump_x_path` doc).
assert_eq!(
edges::curve_bump_x_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0C30,0 30,0 60,0"
);
assert_eq!(
edges::curve_bump_x_path(&pts(&VERTICAL)),
"M100,50C100,50 100,120 100,120C100,120 100,190 100,190"
);
assert_eq!(
edges::curve_bump_x_path(&pts(&HORIZONTAL)),
"M50,100C85,100 85,100 120,100C155,100 155,100 190,100"
);
assert_eq!(
edges::curve_bump_x_path(&pts(&DUPLICATE)),
"M0,0C20,0 20,40 40,40C40,40 40,40 40,40C60,40 60,80 80,80"
);
assert_eq!(edges::curve_bump_x_path(&pts(&RIGHT_ANGLE[..1])), "M0,0");
assert_eq!(edges::curve_bump_x_path(&[]), "");
}
#[test]
fn curve_bump_y_matches_d3() {
assert_eq!(
edges::curve_bump_y_path(&pts(&RIGHT_ANGLE)),
"M0,0C0,0 60,0 60,0C60,30 60,30 60,60"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&FOUR_POINT)),
"M0,0C0,0 40,0 40,0C40,20 40,20 40,40C40,40 80,40 80,40"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&UNEVEN)),
"M0,0C0,0 10,0 10,0C10,15 40,15 40,30C40,32.5 90,32.5 90,35"
);
assert_ne!(
edges::curve_bump_x_path(&pts(&UNEVEN)),
edges::curve_bump_y_path(&pts(&UNEVEN)),
"bumpX and bumpY must draw differently"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&RIGHT_ANGLE[..2])),
"M0,0C0,0 60,0 60,0"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&VERTICAL)),
"M100,50C100,85 100,85 100,120C100,155 100,155 100,190"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&HORIZONTAL)),
"M50,100C50,100 120,100 120,100C120,100 190,100 190,100"
);
assert_eq!(
edges::curve_bump_y_path(&pts(&DUPLICATE)),
"M0,0C0,20 40,20 40,40C40,40 40,40 40,40C40,60 80,60 80,80"
);
assert_eq!(edges::curve_bump_y_path(&pts(&RIGHT_ANGLE[..1])), "M0,0");
assert_eq!(edges::curve_bump_y_path(&[]), "");
}
/// `rounded` is mermaid's own curve, not d3-shape's — so what it is pinned against is mermaid's
/// own `edges.js::generateRoundedPath`, ported the same way (real function, run through Node,
/// same string convention) rather than hand-derived. `radius` is [`edges::CORNER_RADIUS`] (5),
/// the same value `Curve::path` calls this with — matching what `fix_corners` uses for every
/// other curve, per this module's own "why `radius` is a parameter" doc on `rounded_path`.
#[test]
fn rounded_curve_matches_mermaid() {
let radius = edges::CORNER_RADIUS;
assert_eq!(
edges::rounded_path(&pts(&[(0.0, 0.0), (0.0, 40.0), (40.0, 40.0)]), radius),
"M0,0L0,32.929Q0,40 7.071,40L40,40"
);
assert_eq!(
edges::rounded_path(&pts(&UNEVEN), radius),
"M0,0L5,0Q10,0 13.536,3.536L29.483,19.483Q40,30 54.799,31.48L90,35"
);
// A straight run (no bend at all — every point collinear) is left exactly straight: the
// corner-detection angle is `π`, which trips `generateRoundedPath`'s own "too close to 180°"
// guard, the same guard a real flowchart route can hit on an unbent middle waypoint.
assert_eq!(
edges::rounded_path(&pts(&[(0.0, 0.0), (50.0, 0.0), (100.0, 0.0)]), radius),
"M0,0L50,0L100,0"
);
assert_eq!(
edges::rounded_path(&pts(&RIGHT_ANGLE[..2]), radius),
"M0,0L60,0",
"two points is just a line, corner or not"
);
// `VERTICAL`/`HORIZONTAL` are themselves collinear runs (no bend), so — like the straight run
// above — every corner-detection angle is `π` and nothing is rounded; `DUPLICATE` has a
// zero-length segment at its middle point, which `generateRoundedPath`'s own `len1 < epsilon`
// guard catches the same way.
assert_eq!(
edges::rounded_path(&pts(&VERTICAL), radius),
"M100,50L100,120L100,190"
);
assert_eq!(
edges::rounded_path(&pts(&HORIZONTAL), radius),
"M50,100L120,100L190,100"
);
assert_eq!(
edges::rounded_path(&pts(&DUPLICATE), radius),
"M0,0L40,40L40,40L80,80"
);
assert_eq!(edges::rounded_path(&pts(&RIGHT_ANGLE[..1]), radius), "M0,0");
assert_eq!(edges::rounded_path(&[], radius), "");
}
/// All 13 of mermaid's `flowchart.curve` spellings parse to their own, distinct [`Curve`] — the
/// mutation guard against `Curve::parse`'s match arms drifting out of sync with the enum (a copy-
/// pasted arm pointing at the wrong variant would make two names parse to the same curve and this
/// test would be the only thing that notices, since nothing else compares parse results against
/// each other).
#[test]
fn every_curve_name_parses_to_a_distinct_curve() {
let names = [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
];
let parsed: Vec<Curve> = names.iter().map(|s| Curve::parse(s)).collect();
for (i, a) in parsed.iter().enumerate() {
for (j, b) in parsed.iter().enumerate() {
if i != j {
assert_ne!(
a, b,
"{} and {} must not parse to the same Curve",
names[i], names[j]
);
}
}
}
}
/// The eight new curves draw eight different shapes for the same bent waypoints — the same
/// "must differ from each other" guard `step_variants_differ_from_each_other_and_match_d3` runs
/// for the first five, extended to the rest, over a point set with an actual bend (two points
/// would let several of these agree by accident: `curveLinear`-shaped coincidences already bit
/// this file once, `different_curves_draw_different_svg_path_data`'s own doc).
#[test]
fn the_eight_new_curves_draw_different_paths_from_each_other() {
let p = pts(&UNEVEN);
let named: Vec<(&str, String)> = vec![
("natural", edges::curve_natural_path(&p)),
("cardinal", edges::curve_cardinal_path(&p)),
("catmullRom", edges::curve_catmull_rom_path(&p)),
("monotoneX", edges::curve_monotone_x_path(&p)),
("monotoneY", edges::curve_monotone_y_path(&p)),
("bumpX", edges::curve_bump_x_path(&p)),
("bumpY", edges::curve_bump_y_path(&p)),
("rounded", edges::rounded_path(&p, edges::CORNER_RADIUS)),
];
for i in 0..named.len() {
for j in (i + 1)..named.len() {
assert_ne!(
named[i].1, named[j].1,
"{} and {} must draw differently",
named[i].0, named[j].0
);
}
}
}
/// `Curve::parse(name).path(points)` reaches the exact free function this section's own
/// `_matches_d3`/`_matches_mermaid` tests already pinned against upstream — for every one of the
/// 13 names, not just the eight new ones.
///
/// This is not redundant with the `_matches_d3` tests above: those call `edges::curve_natural_path`
/// (etc.) **directly**, so a mistake in `Curve::parse`'s match arms or in `Curve::path`'s dispatch
/// — the wiring between a config string and the function that actually draws it — is invisible to
/// them. A mutation proved the gap real: swapping `Curve::path`'s `MonotoneX` arm to call
/// `curve_natural_path` instead of `curve_monotone_x_path` left every other test in this file
/// green, `curve_monotone_x_matches_d3` included, because that test never goes through
/// `Curve::path` at all. This test is the one built to catch exactly that swap.
type CurvePathFn = fn(&[Point]) -> String;
#[test]
fn curve_parse_and_path_reach_the_function_that_was_pinned_against_upstream() {
let p = pts(&UNEVEN);
let cases: &[(&str, CurvePathFn)] = &[
("basis", edges::curve_basis_path),
("linear", edges::polyline_path),
("natural", edges::curve_natural_path),
("cardinal", edges::curve_cardinal_path),
("catmullRom", edges::curve_catmull_rom_path),
("monotoneX", edges::curve_monotone_x_path),
("monotoneY", edges::curve_monotone_y_path),
("bumpX", edges::curve_bump_x_path),
("bumpY", edges::curve_bump_y_path),
];
for (name, f) in cases {
assert_eq!(
Curve::parse(name).path(&p),
f(&p),
"Curve::parse(\"{name}\").path(...) must reach the same function {name} was pinned \
against upstream with"
);
}
// `rounded` takes a radius, so it is checked against `Curve::path`'s own hardcoded
// `CORNER_RADIUS` argument rather than fitting the `fn(&[Point]) -> String` shape above.
assert_eq!(
Curve::parse("rounded").path(&p),
edges::rounded_path(&p, edges::CORNER_RADIUS)
);
// `step`/`stepBefore`/`stepAfter` take a `t` argument `step_variants_differ_from_each_other_
// and_match_d3` already pins by value; checked here for wiring completeness the same way.
assert_eq!(Curve::parse("step").path(&p), edges::step_path(&p, 0.5));
assert_eq!(
Curve::parse("stepBefore").path(&p),
edges::step_path(&p, 0.0)
);
assert_eq!(
Curve::parse("stepAfter").path(&p),
edges::step_path(&p, 1.0)
);
}
/// The dispatch-completeness check above (`curve_parse_and_path_reach_the_function_that_was_
/// pinned_against_upstream`), but for the exact degenerate shape that shipped a real bug: a
/// vertical run of waypoints — `flowchart TD`'s ordinary look, konoma's default direction —
/// through `Curve::parse("monotoneX").path(...)`, the real config-to-render path, not the free
/// function directly. The bug this closes (`js_min`'s own doc has the mechanism) reached
/// production through exactly this call chain — `[ui] mermaid_curve = "monotoneX"` on a plain
/// `flowchart TD` — so the regression test for it has to go through the same chain, not just the
/// free function `curve_monotone_x_matches_d3` already pins directly.
type CurveDegenerateCase = (&'static str, &'static [(f64, f64)], &'static str);
#[test]
fn all_thirteen_curves_match_d3_or_mermaid_on_degenerate_points_through_curve_path() {
let cases: &[CurveDegenerateCase] = &[
(
"basis",
&VERTICAL,
"M100,50L100,61.667C100,73.333 100,96.667 100,120\
C100,143.333 100,166.667 100,178.333L100,190",
),
("linear", &VERTICAL, "M100,50 L100,120 L100,190"),
// `step`/`stepBefore`/`stepAfter` genuinely diverge from raw d3 here — not a bug in
// either implementation, and not related to the NaN fix this test exists for. d3's own
// `Step.point` always emits two `lineTo` calls per point unconditionally (never checking
// whether either has zero length), so a vertical run's raw d3 output carries redundant
// same-coordinate legs (`edges::step_path`'s own module doc did not anticipate this —
// it reasoned about the *deferred final leg* `curveStep` (t=0.5) leaves for `lineEnd`,
// not about a *zero-dx segment* dropping a leg outright). konoma's own `step_path` skips
// a leg whose two endpoints coincide (`EPS`-guarded), so it collapses straight to the
// three real points instead. Both draw the *identical picture* — a zero-length line
// segment is invisible in any renderer — so this is a cosmetic `d`-string difference,
// not a rendering one, and out of scope for the NaN bug; flagged, not silently patched.
("step", &VERTICAL, "M100,50L100,120L100,190"),
("stepBefore", &VERTICAL, "M100,50L100,120L100,190"),
("stepAfter", &VERTICAL, "M100,50L100,120L100,190"),
(
"natural",
&VERTICAL,
"M100,50C100,73.333 100,96.667 100,120\
C100,143.333 100,166.667 100,190",
),
(
"cardinal",
&VERTICAL,
"M100,50C100,50 100,96.667 100,120C100,143.333 100,190 100,190",
),
(
"catmullRom",
&VERTICAL,
"M100,50C100,50 100,96.667 100,120C100,143.333 100,190 100,190",
),
(
"monotoneX",
&VERTICAL,
"M100,50C100,50 100,120 100,120C100,120 100,190 100,190",
),
(
"monotoneY",
&HORIZONTAL,
"M50,100C50,100 120,100 120,100C120,100 190,100 190,100",
),
(
"bumpX",
&VERTICAL,
"M100,50C100,50 100,120 100,120C100,120 100,190 100,190",
),
(
"bumpY",
&HORIZONTAL,
"M50,100C50,100 120,100 120,100C120,100 190,100 190,100",
),
("rounded", &VERTICAL, "M100,50L100,120L100,190"),
];
for (name, raw, expected) in cases {
let p = pts(raw);
assert_eq!(
Curve::parse(name).path(&p),
*expected,
"Curve::parse(\"{name}\").path(...) on a degenerate point set"
);
assert!(
!Curve::parse(name).path(&p).contains("NaN"),
"{name} must not emit NaN through Curve::path"
);
}
}
/// **Mechanical**, not example-based: every one of the 13 curve names, over a battery of
/// degenerate point sets (vertical, horizontal, and every other axis-aligned-or-duplicate shape
/// below), must never emit `NaN` or `Infinity` into the `d` attribute it draws — regardless of
/// whether this crate happens to have a hand-written expected value for that exact combination.
/// The bug this exists to make impossible to reintroduce (`js_min`'s own doc has the mechanism)
/// was found by looking at a rendered picture, not by a test — this is the test that should have
/// caught it, and the reason it is swept over every curve rather than just `monotoneX`/`monotoneY`
/// is that the next curve to grow a `NaN` might not be either of those two.
#[test]
fn no_curve_ever_emits_nan_or_infinite_coordinates() {
let names = [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
];
// Every point set is deliberately degenerate in a different way: two axis-aligned runs (the
// exact shape that broke `monotoneX`/`monotoneY`), a run with a duplicated interior point, a
// single repeated point three times over, and a two-point vertical/horizontal edge (the
// *most* common real shape of all — an ordinary two-node `flowchart TD` edge).
let degenerate: &[&[(f64, f64)]] = &[
&VERTICAL,
&HORIZONTAL,
&DUPLICATE,
&[(50.0, 50.0), (50.0, 50.0), (50.0, 50.0)],
&[(0.0, 0.0), (0.0, 100.0)],
&[(0.0, 0.0), (100.0, 0.0)],
&[(100.0, 100.0), (100.0, 100.0)],
];
for name in names {
for raw in degenerate {
let p = pts(raw);
let d = Curve::parse(name).path(&p);
assert!(
!d.contains("NaN") && !d.contains("inf") && !d.contains("Inf"),
"{name} emitted a non-finite coordinate for {raw:?}: {d}"
);
}
}
}
/// `Curve::rounds_corners` matches every released mermaid version's actual gate in `edges.js`:
/// `fixCorners` runs unconditionally, for **every** curve, `rounded` included on `develop` only
/// by an exemption added the same commit that introduced it (`Curve::rounds_corners`'s own doc
/// has the versioned evidence — `mermaid@11.4.1`/`mermaid@11.12.0` have no condition at all).
/// `Rounded` is the *only* curve this crate exempts, and only because it rounds every corner
/// itself at its own radius — running `fix_corners` first would double-round the same corner.
///
/// This test used to assert the opposite for `Linear`/`Step`/`StepBefore`/`StepAfter` — a rule
/// invented from how those curves *look* (chosen for a sharp angle, so surely nothing should
/// round it) rather than checked against upstream. It was wrong on both released versions
/// checked; the corrected list below is every curve *but* `Rounded`.
#[test]
fn rounds_corners_matches_mermaids_fix_corners_gate() {
for curve in [
Curve::Basis,
Curve::Linear,
Curve::Step,
Curve::StepBefore,
Curve::StepAfter,
Curve::Natural,
Curve::Cardinal,
Curve::CatmullRom,
Curve::MonotoneX,
Curve::MonotoneY,
Curve::BumpX,
Curve::BumpY,
] {
assert!(curve.rounds_corners(), "{curve:?} must run fix_corners");
}
assert!(
!Curve::Rounded.rounds_corners(),
"Curve::Rounded must not run fix_corners — it rounds corners itself"
);
}
// ---------------------------------------------------------------------------------------------
// 10-c. `%%{init}%%`'s `flowchart.curve` — the priority order `spec_of`'s own doc states:
// `linkStyle <n> interpolate` > `linkStyle default interpolate` > `%%{init}%%`'s `flowchart.curve`
// > `[ui] mermaid_curve`.
// ---------------------------------------------------------------------------------------------
/// `%%{init: {"flowchart": {"curve": "linear"}}}%%` overrides `[ui] mermaid_curve` — the weakest
/// link in the priority chain beating the weaker-still config default.
#[test]
fn init_directive_curve_overrides_the_config_default() {
let d = laid_out_curve(
"%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\nflowchart TD\n A --> B",
"step",
);
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"the init directive must win over ui.mermaid_curve"
);
}
/// An edge's own `linkStyle interpolate` still wins over `%%{init}%%` — the strongest link in the
/// chain beating the middle one, with a config default that agrees with neither so the test
/// cannot pass by two of the three coinciding.
#[test]
fn link_style_interpolate_overrides_init_directive_curve() {
let d = laid_out_curve(
"%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\n\
flowchart TD\n A --> B\n linkStyle 0 interpolate step",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Step,
"linkStyle interpolate must win over both the init directive and the config default"
);
}
/// `linkStyle default interpolate` sits between the two: it loses to this edge's own indexed
/// `linkStyle`, but beats the init directive for every edge that names no index of its own.
#[test]
fn link_style_default_interpolate_sits_between_init_and_indexed_link_style() {
let d = laid_out_curve(
"%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\n\
flowchart TD\n A --> B\n C --> D\n \
linkStyle default interpolate step\n linkStyle 1 interpolate stepBefore",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Step,
"linkStyle default interpolate must win over the init directive for an edge with no index override"
);
assert_eq!(
d.edges[1].curve,
Curve::StepBefore,
"linkStyle 1's own interpolate must still win over linkStyle default"
);
}
/// `%%{init: {"theme": "dark"}}%%` — a directive that names no `flowchart.curve` at all — is still
/// completely ignored for curve purposes, exactly as it always was (the corpus already has this
/// exact shape, and `docs/STATUS.md`'s "既定の出力は変わらない" invariant is precisely this: only
/// `flowchart.curve` reaching in is new, every other key must draw exactly what it drew before
/// this crate started reading `%%{init}%%` at all).
#[test]
fn init_directive_naming_only_theme_still_does_not_touch_curve() {
let d = laid_out_curve(
"%%{init: {\"theme\": \"dark\"}}%%\nflowchart TD\n A --> B",
"step",
);
assert_eq!(
d.edges[0].curve,
Curve::Step,
"a theme-only init directive must leave the config default untouched"
);
}
/// Quote style, whitespace, multi-line bodies and key order are all noise `init_flowchart_curve`
/// has to see through — the exact axes the task called out. Every source below sets the same
/// `flowchart.curve: linear` and must resolve to the same [`Curve::Linear`].
#[test]
fn init_directive_curve_survives_formatting_variation() {
let sources = [
// Double-quoted, single line — the canonical shape.
"%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\nflowchart TD\n A --> B",
// Single-quoted — mermaid's own examples use this spelling just as often.
"%%{init: {'flowchart': {'curve': 'linear'}}}%%\nflowchart TD\n A --> B",
// Multi-line, indented, mixed quoting.
"%%{init: {\n \"flowchart\": {\n 'curve': \"linear\"\n }\n}}%%\n\
flowchart TD\n A --> B",
// `flowchart` is not the first key in the init object.
"%%{init: {\"theme\": \"dark\", \"flowchart\": {\"curve\": \"linear\"}}}%%\n\
flowchart TD\n A --> B",
// `curve` is not the first key inside `flowchart`.
"%%{init: {\"flowchart\": {\"htmlLabels\": false, \"curve\": \"linear\"}}}%%\n\
flowchart TD\n A --> B",
// Bare (unquoted) keys and value — valid JSON5, which is what mermaid's directive body
// actually is.
"%%{init: {flowchart: {curve: linear}}}%%\nflowchart TD\n A --> B",
// No space after the colons.
"%%{init:{\"flowchart\":{\"curve\":\"linear\"}}}%%\nflowchart TD\n A --> B",
];
for src in sources {
let d = laid_out_curve(src, "basis");
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"must resolve to Linear regardless of formatting: {src}"
);
}
}
/// A malformed `%%{init}%%` — bad JSON, a `curve` of the wrong type, `flowchart` misplaced — must
/// never crash, and must fall back all the way to the config default, exactly like an unrecognised
/// curve *name* already does (PRD design principle #3: an unknown or malformed value never blocks
/// a render).
#[test]
fn malformed_init_directive_falls_back_without_crashing() {
let sources = [
// `curve` is a number, not a string.
"%%{init: {\"flowchart\": {\"curve\": 5}}}%%\nflowchart TD\n A --> B",
// `curve` is itself an object.
"%%{init: {\"flowchart\": {\"curve\": {\"x\": 1}}}}%%\nflowchart TD\n A --> B",
// `curve` is an array.
"%%{init: {\"flowchart\": {\"curve\": [\"linear\"]}}}%%\nflowchart TD\n A --> B",
// `flowchart` is a string, not an object — nothing to look a `curve` up inside.
"%%{init: {\"flowchart\": \"oops\"}}%%\nflowchart TD\n A --> B",
// The directive's own JSON never closes.
"%%{init: {\"flowchart\": {\"curve\": \"linear\"\nflowchart TD\n A --> B",
// `curve` at the top level, not nested under `flowchart` at all.
"%%{init: {\"curve\": \"linear\"}}%%\nflowchart TD\n A --> B",
// Empty object.
"%%{init: {}}%%\nflowchart TD\n A --> B",
];
for src in sources {
let d = laid_out_curve(src, "step");
assert_eq!(
d.edges[0].curve,
Curve::Step,
"a malformed init directive must fall back to the config default: {src}"
);
let svg = render_curve(src, "dark", "step")
.unwrap_or_else(|e| panic!("must still render despite a malformed directive: {e}"));
assert!(svg.contains("<svg"));
}
}
/// CJK labels alongside a real `%%{init}%%` `flowchart.curve` — the one combination this section's
/// other tests never exercise together, and the exact kind of "two features nobody tried at once"
/// gap `CLAUDE.md`'s testing policy calls out by name.
#[test]
fn cjk_labels_render_with_an_init_directive_curve() {
let src = "%%{init: {\"flowchart\": {\"curve\": \"monotoneX\"}}}%%\n\
flowchart TD\n A[ツリー] -->|Enter| B{種別を解決}\n B -->|画像| C[全画面プレビュー]";
let d = laid_out_curve(src, "basis");
assert_eq!(d.edges[0].curve, Curve::MonotoneX);
let svg = render_curve(src, "dark", "basis").unwrap_or_else(|e| panic!("must render: {e}"));
assert!(svg.contains("<svg"));
}
/// The wiring reaches all the way to the emitted `d=` attribute, over a corpus source with a real
/// bend (`long-edge`'s `A --> E` spans multiple ranks, so dagre gives it waypoints in between —
/// on two points `curve_basis_path` and `polyline_path` already agree, which would make this test
/// pass by accident).
#[test]
fn different_curves_draw_different_svg_path_data() {
let (_, src) = CORPUS
.iter()
.find(|(name, _)| *name == "long-edge")
.expect("corpus must still have `long-edge`");
let basis = render_curve(src, "dark", "basis").expect("renders");
let linear = render_curve(src, "dark", "linear").expect("renders");
let step = render_curve(src, "dark", "step").expect("renders");
assert_ne!(
basis, linear,
"a bent edge must draw differently under linear"
);
assert_ne!(basis, step, "a bent edge must draw differently under step");
assert_ne!(
linear, step,
"linear and step must draw differently from each other too"
);
}
/// CJK labels — konoma's standing gap in test coverage (`CLAUDE.md`'s own reminder) — must render
/// under every implemented curve without panicking.
#[test]
fn cjk_labels_render_under_every_curve() {
let src = "flowchart TD\n A[ツリー] -->|Enter| B{種別を解決}\n \
B -->|画像| C[全画面プレビュー]\n B -->|テキスト| D[窓読み]\n D --> A";
for curve in [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
] {
let svg = render_curve(src, "dark", curve).unwrap_or_else(|e| panic!("{curve}: {e}"));
assert!(
svg.contains("<svg"),
"{curve}: CJK labels must still render"
);
}
}
// ---------------------------------------------------------------------------------------------
// 10-d. Coverage audit (2026-08-29): gaps found while auditing the curve feature's test coverage
// against a 35-point checklist. Each test below closes exactly one point the checklist named —
// see the doc comment for which.
// ---------------------------------------------------------------------------------------------
/// Checklist A4: an empty or whitespace-only curve name is exactly as unrecognised as any other
/// bad spelling — `Curve::parse` has no special case for either, so both fall through its
/// catch-all arm to `Curve::Basis`, the same fallback `unknown_curve_falls_back_to_basis_without_
/// crashing` already pins for `""`. That test never tried a *whitespace* string (as opposed to a
/// truly empty one), which is the shape checked here, both directly and through the full
/// `[ui] mermaid_curve` → render pipeline.
#[test]
fn whitespace_only_curve_name_falls_back_to_basis() {
assert_eq!(Curve::parse(" "), Curve::Basis);
assert_eq!(Curve::parse("\t"), Curve::Basis);
assert_eq!(Curve::parse("\n"), Curve::Basis);
let d = laid_out_curve("flowchart TD\n A --> B", " ");
assert_eq!(d.edges[0].curve, Curve::Basis);
let svg = render_curve("flowchart TD\n A --> B", "dark", " ")
.expect("a blank curve name must still render, as Curve::Basis");
assert!(svg.contains("<svg"));
}
/// Checklist B11: mermaid re-applies each `%%{init}%%` directive over its running config in
/// source order, so a *later* directive's `flowchart.curve` overrides an earlier one's —
/// `preprocess::strip_directives`'s own doc states this as the intended behaviour, but no
/// existing test actually put two init directives naming `flowchart.curve` in one source.
#[test]
fn a_second_init_directive_overrides_the_first_ones_curve() {
let d = laid_out_curve(
"%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\n\
%%{init: {\"flowchart\": {\"curve\": \"step\"}}}%%\n\
flowchart TD\n A --> B",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Step,
"the second init directive must win over the first"
);
}
/// Checklist B12: an `%%{init}%%` directive is not required to sit before the diagram's header —
/// `preprocess::strip_directives` scans the whole source rather than assuming a fixed position.
/// Every other init-directive test in this section puts the directive first; this one puts it
/// after the header and after an edge, which no existing test does.
#[test]
fn an_init_directive_after_the_header_still_sets_the_curve() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n \
%%{init: {\"flowchart\": {\"curve\": \"linear\"}}}%%\n B --> C",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"a mid-diagram init directive must still set the chart-wide curve"
);
assert_eq!(d.edges[1].curve, Curve::Linear);
}
/// Checklist C14 for `interpolate` specifically: `linkStyle 0,1,2 interpolate <curve>` — several
/// indices sharing one `interpolate` argument. `link_style_with_multiple_indices_reaches_every_
/// named_edge` already proves this shape for a plain style declaration; this is the same proof
/// for `interpolate`, which that test never exercised.
#[test]
fn link_style_interpolate_with_multiple_indices_reaches_every_named_edge() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n B --> C\n C --> D\n D --> E\n \
linkStyle 0,1,2 interpolate linear",
"basis",
);
assert_eq!(d.edges.len(), 4);
for i in 0..3 {
assert_eq!(
d.edges[i].curve,
Curve::Linear,
"edge {i} is named by `linkStyle 0,1,2 interpolate linear`"
);
}
assert_eq!(
d.edges[3].curve,
Curve::Basis,
"edge 3 (D->E) was not named, and must keep the chart-wide default"
);
}
/// Checklist C16: `linkStyle` naming an index past the last edge must not crash, and must leave
/// every real edge untouched. The adversarial sweep in `flowchart/tests.rs` already proves the
/// *parser* survives `linkStyle 99 stroke:red` on a source with no edges at all; this proves the
/// *render* pipeline does too, on a chart that has a real edge, with `interpolate` specifically,
/// and that the phantom index changes nothing real.
#[test]
fn link_style_interpolate_naming_an_index_past_the_last_edge_does_not_crash() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n linkStyle 5 interpolate linear",
"step",
);
assert_eq!(d.edges.len(), 1);
assert_eq!(
d.edges[0].curve,
Curve::Step,
"an out-of-range linkStyle index must touch no real edge"
);
let svg = render_curve(
"flowchart TD\n A --> B\n linkStyle 5 interpolate linear",
"dark",
"step",
)
.expect("an out-of-range linkStyle index must not crash the render");
assert!(svg.contains("<svg"));
}
/// Checklist C17: `linkStyle 0 interpolate <curve> <styles>` — an `interpolate` argument followed
/// by ordinary style declarations on the same statement — must apply *both*: the curve reaches
/// `PlacedEdge::curve` and the style reaches `PlacedEdge::style`, from one parse of one
/// statement. `flowchart::tests::link_style_reads_its_index_list_its_default_form_and_its_
/// interpolation` already proves the *parser* keeps both fields distinct; this is the render-level
/// proof that neither field's cascade clobbers the other's.
#[test]
fn link_style_interpolate_and_stroke_on_the_same_statement_both_apply() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n linkStyle 0 interpolate linear stroke:#1f6feb",
"basis",
);
assert_eq!(d.edges[0].curve, Curve::Linear, "the curve must apply");
assert_eq!(
d.edges[0]
.style
.as_ref()
.expect("the style must apply too")
.stroke
.as_deref(),
Some("#1f6feb")
);
}
/// Checklist G31: `mermaid_curve` reaches only a flowchart's own edges. `spec_of`'s own doc states
/// that every other diagram kind's `SpecEdge::curve` is hardcoded to `Curve::Basis`, and the real
/// dispatcher (`preview::markdown::mermaid_to_svg_reason_flow`) does not even thread a `curve`
/// argument through to any other renderer's entry point. This is the end-to-end proof, through the
/// exact function the app calls (`mermaid_to_svg_curve`), for three diagram kinds.
#[test]
fn non_flowchart_diagrams_ignore_mermaid_curve() {
use crate::preview::markdown::mermaid_to_svg_curve;
let cases = [
"stateDiagram-v2\n [*] --> A\n A --> B\n B --> [*]",
"classDiagram\n A --|> B",
"erDiagram\n A ||--o{ B : has",
];
for src in cases {
let basis = mermaid_to_svg_curve(src, "dark", "basis").expect("must render");
let step = mermaid_to_svg_curve(src, "dark", "step").expect("must render");
assert_eq!(
basis, step,
"a non-flowchart diagram must draw identically regardless of mermaid_curve: {src}"
);
}
}
/// Checklist H34: `curve` still reaches an edge that names a subgraph as one of its own ends —
/// the `edges::End::Cluster` path through `route`, which no existing curve test exercises (every
/// other curve test in this section connects two ordinary nodes). `PlacedEdge::curve` is carried
/// unconditionally regardless of which `End` variant routed the edge (`lay_out_spec`'s own
/// `curve: edge.curve` push), so this is the proof at the level a reader would actually see: a
/// diagram with an edge crossing a subgraph's frame must still draw visibly differently under two
/// different curves, the same way `different_curves_draw_different_svg_path_data` proves it for
/// an ordinary bent edge.
#[test]
fn curve_reaches_an_edge_that_crosses_a_subgraph_frame() {
let src = "flowchart LR\n subgraph one [First]\n A --> B\n end\n \
subgraph two [Second]\n C --> D\n end\n one --> two\n E --> one";
let d = laid_out_curve(src, "step");
assert!(
!d.clusters.is_empty(),
"the source must actually produce a subgraph frame"
);
for e in &d.edges {
assert_eq!(
e.curve,
Curve::Step,
"every edge must resolve to the configured curve, cluster-bound or not"
);
}
let basis = render_curve(src, "dark", "basis").expect("renders");
let step = render_curve(src, "dark", "step").expect("renders");
assert_ne!(
basis, step,
"a subgraph-bearing diagram must still draw visibly differently under two curves"
);
}
/// Checklist H35: the legacy `graph` keyword is the same grammar as `flowchart`
/// (`flowchart/parser.rs`'s header parsing accepts both), so `curve` must resolve through it
/// identically — checked directly rather than assumed, since every other curve test in this file
/// spells the keyword `flowchart`. Both the config-default path and `linkStyle ... interpolate`
/// are checked, not just one.
#[test]
fn curve_resolves_identically_under_the_legacy_graph_keyword() {
let flowchart = laid_out_curve("flowchart LR\n A --> B", "monotoneX");
let graph = laid_out_curve("graph LR\n A --> B", "monotoneX");
assert_eq!(flowchart.edges[0].curve, Curve::MonotoneX);
assert_eq!(graph.edges[0].curve, Curve::MonotoneX);
let flowchart2 = laid_out_curve(
"flowchart LR\n A --> B\n linkStyle 0 interpolate step",
"basis",
);
let graph2 = laid_out_curve(
"graph LR\n A --> B\n linkStyle 0 interpolate step",
"basis",
);
assert_eq!(flowchart2.edges[0].curve, Curve::Step);
assert_eq!(graph2.edges[0].curve, Curve::Step);
}
// ---------------------------------------------------------------------------------------------
// 10-e. Independent second audit (2026-08-29): every existing degenerate-point/NaN-safety test
// above (`no_curve_ever_emits_nan_or_infinite_coordinates`,
// `all_thirteen_curves_match_d3_or_mermaid_on_degenerate_points_through_curve_path`) runs the 13
// curves over *hand-picked* point sets (`VERTICAL`, `HORIZONTAL`, `UNEVEN`, `DUPLICATE`, ...).
// That is exactly the shape of gap this feature has bitten konoma with once already: a synthetic
// point list proved the arithmetic safe while the *route dagre actually produces* for a real
// diagram — a self-loop, an edge crossing a subgraph frame, a parallel `A & B --> C & D` fan —
// never went through it, because those routes are built by `route`/`clip`'s own dedupe-and-insert
// logic (`edges.rs`'s module docs, steps 1-3) before a single coordinate ever reaches
// `Curve::path`. Nothing in this file had, until now, run the *specification corpus* (`CORPUS`,
// chosen from real diagram shapes — memory `corpus-from-spec-not-from-bugs`) across *every* curve
// name; every existing corpus-based curve test picks one corpus entry (`"long-edge"`) and at most
// three curves (`different_curves_draw_different_svg_path_data`), or one curve name across the
// whole corpus (`corpus_golden`, always `Curve::Basis`). This closes that cross product.
// ---------------------------------------------------------------------------------------------
/// Every entry in [`CORPUS`] — self-loop, edges crossing a subgraph frame both from inside and
/// from outside (`subgraph-bypass`, `subgraph-endpoint`), the `&`-group fan-out (`amp-chain`),
/// CJK labels, and the `classDef`/`linkStyle` cascade — run through **every** one of the 13 curve
/// names. Each combination must render, must contain no `NaN`/`Infinity` coordinate, must come
/// out a finite, positive size, and must actually rasterise — the same bar
/// `awkward_sources_produce_a_diagram_or_an_error_and_never_a_panic` sets for the default curve
/// alone, swept here over the full curve set instead.
///
/// Also covers the two structural cases no [`CORPUS`] entry has at all: a chart with nodes but
/// **zero** edges (so `Curve::path` is never even called — `spec_of`'s edge loop must still not
/// choke on an empty iterator, for every curve name it is handed) and a single node with no edges.
#[test]
fn every_corpus_source_survives_every_curve() {
if !text_metrics::fonts_available() {
return;
}
let curves = [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
];
let extra: &[(&str, &str)] = &[
("zero-edges", "flowchart TD\n A[one]\n B[two]\n C[three]"),
("single-node", "flowchart TD\n A[Solo]"),
];
for (name, src) in CORPUS.iter().chain(extra) {
for curve in curves {
let svg = render_curve(src, "dark", curve)
.unwrap_or_else(|e| panic!("{name} under {curve}: must render: {e}"));
assert!(
!svg.contains("NaN") && !svg.contains("inf") && !svg.contains("Inf"),
"{name} under {curve}: emitted a non-finite coordinate: {svg}"
);
let d = laid_out_curve(src, curve);
assert!(
d.width.is_finite() && d.height.is_finite() && d.width > 0.0 && d.height > 0.0,
"{name} under {curve}: {}x{} is not a drawable size",
num(d.width),
num(d.height)
);
assert!(
crate::preview::svg::rasterize_bytes(svg.as_bytes(), FsPath::new("m.svg"), 300)
.is_some(),
"{name} under {curve}: the output did not rasterise"
);
}
}
}
/// A far larger and more cyclic graph than anything in [`CORPUS`] (whose entries are all a
/// handful of edges) — a long rank chain closed into a cycle, and a chain of nested subgraphs —
/// run through every curve. The point sets a curve function sees here (many more waypoints per
/// edge from the extra ranks, more coincident-rank runs) are shaped differently from any
/// [`CORPUS`] entry's, which matters because the one real curve bug this crate has shipped
/// (`js_min`'s own doc, the `monotoneX`/vertical-run `NaN`) was found on a real rendered diagram,
/// not on a synthetic point list — so this is deliberately a *diagram*, built the way
/// `awkward_sources_produce_a_diagram_or_an_error_and_never_a_panic` builds its `wide`/`deep`
/// sources, rather than another hand-picked `&[Point]`.
#[test]
fn a_large_cyclic_and_deeply_nested_graph_survives_every_curve() {
if !text_metrics::fonts_available() {
return;
}
let mut wide = String::from("flowchart LR\n");
for i in 0..40 {
wide.push_str(&format!(" n{i} --> n{}\n", i + 1));
}
wide.push_str(" n0 --> n40\n n40 --> n0\n");
let mut nested = String::from("flowchart TD\n");
for i in 0..8 {
nested.push_str(&format!(" subgraph s{i} [Level {i}]\n"));
}
nested.push_str(" A --> B\n");
for _ in 0..8 {
nested.push_str(" end\n");
}
nested.push_str(" s0 --> C\n C --> s7\n");
let curves = [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
];
for (label, src) in [
("wide-cycle", wide.as_str()),
("deep-nested", nested.as_str()),
] {
for curve in curves {
let svg = render_curve(src, "dark", curve)
.unwrap_or_else(|e| panic!("{label} under {curve}: must render: {e}"));
assert!(
!svg.contains("NaN") && !svg.contains("inf") && !svg.contains("Inf"),
"{label} under {curve}: emitted a non-finite coordinate"
);
}
}
}
/// A second `linkStyle <n> interpolate` statement naming the **same** index as an earlier one:
/// mermaid re-applies each statement over its running config in source order (the same rule
/// `a_second_init_directive_overrides_the_first_ones_curve` already pins for `%%{init}%%`), so the
/// later one must win. `spec_of`'s `indexed_interpolate` picks this with `.filter_map(...)
/// .next_back()` over every matching `LinkStyle` — a real, distinct code path (it only does
/// anything different from `.next()` when more than one `LinkStyle` matches the same index) that
/// no existing test ever gives more than one matching statement to: every other `linkStyle
/// interpolate` test in this file names a given index exactly once.
#[test]
fn a_second_link_style_interpolate_on_the_same_index_overrides_the_first() {
let d = laid_out_curve(
"flowchart TD\n A --> B\n \
linkStyle 0 interpolate step\n linkStyle 0 interpolate linear",
"basis",
);
assert_eq!(
d.edges[0].curve,
Curve::Linear,
"a later linkStyle 0 interpolate must override an earlier one naming the same index"
);
// The same rule for `linkStyle default interpolate`, repeated.
let d2 = laid_out_curve(
"flowchart TD\n A --> B\n \
linkStyle default interpolate step\n linkStyle default interpolate linear",
"basis",
);
assert_eq!(
d2.edges[0].curve,
Curve::Linear,
"a later linkStyle default interpolate must override an earlier one"
);
}
// ---------------------------------------------------------------------------------------------
// 10-f. Coverage audit follow-up (2026-08-29): two of the three items the audit flagged as
// unverified. `mermaid_curve`'s interaction with `mermaid_theme`/`mermaid_rows`/`svg_max_px` is
// finished here for `mermaid_theme` (both knobs are plain function parameters at this level) and
// in `app/tests.rs` for `mermaid_rows`/`svg_max_px` (which only exist as `App`/`[ui]` config, not
// as parameters `render_curve`/`mermaid_to_svg_curve` ever take). The third item — text mode never
// even reaching curve resolution — is also in `app/tests.rs`, next to the existing text-mode test.
// ---------------------------------------------------------------------------------------------
/// `[ui] mermaid_curve` and `[ui] mermaid_theme` sit on independent axes: changing one must never
/// move so much as a byte of what the other is responsible for. Checked both directions, so
/// neither can hide behind the other:
///
/// 1. holding theme fixed, every curve must draw the exact same colour-bearing attributes
/// (`fill="…"`/`stroke="…"`) — only the path/label geometry may move;
/// 2. holding curve fixed at something other than the default `basis`, every theme must draw the
/// exact same geometry — only colour may move.
///
/// Direction 2 is the gap `mermaid_themes_change_colours_but_never_font_metrics` (`markdown.rs`)
/// leaves open: that test always renders through `mermaid_to_svg`, which is `render_curve(...,
/// "basis")` by definition, so it has never actually exercised a non-default curve at all.
#[test]
fn mermaid_curve_and_mermaid_theme_are_independent_axes() {
let (_, src) = CORPUS
.iter()
.find(|(name, _)| *name == "long-edge")
.expect("corpus must still have `long-edge`");
fn color_attrs(svg: &str) -> Vec<&str> {
svg.split_whitespace()
.filter(|w| w.starts_with("fill=\"") || w.starts_with("stroke=\""))
.collect()
}
let geometry_of = |svg: &str| -> String {
svg.split_whitespace()
.filter(|w| !w.starts_with("fill=") && !w.starts_with("stroke=\""))
.collect::<Vec<_>>()
.join(" ")
};
// 1. Fixed theme, varying curve.
let basis = render_curve(src, "dark", "basis").expect("renders");
for curve in ["linear", "step", "monotoneX"] {
let other = render_curve(src, "dark", curve).expect("renders");
assert_eq!(
color_attrs(&basis),
color_attrs(&other),
"curve {curve} must not move a single colour attribute away from the basis render"
);
assert_ne!(
basis, other,
"curve {curve} must still change something (the path data) — otherwise this \
comparison is vacuous"
);
}
// 2. Fixed curve (non-default), varying theme.
let linear_dark = render_curve(src, "dark", "linear").expect("renders");
let base_geometry = geometry_of(&linear_dark);
for theme in ["light", "modern", "classic", "mermaid", "forest", "neutral"] {
let other = render_curve(src, theme, "linear").expect("renders");
assert_eq!(
base_geometry,
geometry_of(&other),
"theme {theme} moved curve=\"linear\" geometry, not just colour"
);
assert_ne!(
linear_dark, other,
"theme {theme} must still change colour — otherwise this comparison is vacuous"
);
}
}
/// A hand-built two-point-or-more edge in `curve`, for the geometry tests above — the same shape
/// [`chart::rule`] builds for a chart's rule line, minus the theme/tip decisions this section
/// does not care about.
fn bent_edge(points: Vec<Point>, curve: Curve) -> PlacedEdge {
PlacedEdge {
from: "a".to_string(),
to: "b".to_string(),
points,
gaps: Vec::new(),
tip_start: Tip::None,
tip_end: Tip::None,
stroke: Stroke::Normal,
label: None,
start_label: None,
end_label: None,
badge: None,
series: None,
straight: false,
overlay: false,
style: None,
curve,
tip_matches_line: false,
}
}
// ---------------------------------------------------------------------------------------------
// 10-g. Coverage audit follow-up (2026-08-29), item 2: `linkStyle <n>`'s index over **parallel**
// edges — more than one edge between the same node pair, self-loops included. `spec_of` resolves
// `linkStyle` purely from `chart.edges.iter().enumerate()` (`mod.rs`'s own comment: "`linkStyle`
// indices are positions in `Flowchart::edges`... exactly this iterator's index"), i.e. declaration
// order, before any layout ever runs — but nothing in this file had checked that against a source
// where two edges share both endpoints, the one shape where a bug that resolved the index against
// *layout* order instead (e.g. edges sorted by rank, or self-loops moved to the end of the list —
// both real things a routing pass could plausibly do) would be invisible on every existing test,
// since every existing test's edges are already distinguishable by their `(from, to)` pair alone.
//
// Each test below tells two same-pair edges apart by a distinct `linkStyle`-free discriminator
// (the edge's own label text), so it never has to *assume* `Diagram::edges` preserves declaration
// order — it looks each edge up by what it says, not by where it landed in the output `Vec`.
// ---------------------------------------------------------------------------------------------
/// The label text of an edge, or `""` if it carries none — the discriminator every test in this
/// section uses instead of trusting `d.edges`' own order.
fn edge_label_text(e: &PlacedEdge) -> String {
e.label
.as_ref()
.map(|l| l.label.lines.join("\n"))
.unwrap_or_default()
}
/// Two ordinary parallel `A --> B` edges, told apart by label: `linkStyle 0` must land on the
/// first-declared one (labelled `x`) and `linkStyle 1` on the second (labelled `y`) — never the
/// other way around, and never both on the same edge.
#[test]
fn link_style_index_targets_the_declared_edge_among_parallel_edges() {
let d = laid_out_curve(
"flowchart TD\n A -->|x| B\n A -->|y| B\n \
linkStyle 0 interpolate linear\n linkStyle 1 interpolate step",
"basis",
);
let x = d
.edges
.iter()
.find(|e| edge_label_text(e) == "x")
.expect("the \"x\"-labelled edge must exist");
let y = d
.edges
.iter()
.find(|e| edge_label_text(e) == "y")
.expect("the \"y\"-labelled edge must exist");
assert_eq!(
x.curve,
Curve::Linear,
"linkStyle 0 must land on the first-declared A->B edge (labelled x)"
);
assert_eq!(
y.curve,
Curve::Step,
"linkStyle 1 must land on the second-declared A->B edge (labelled y), not the first"
);
}
/// The same proof over three parallel edges instead of two, so an off-by-one shift (an index
/// resolved one position early or late) cannot accidentally still land on the intended edge the
/// way it might by luck with only two.
#[test]
fn link_style_index_targets_the_declared_edge_among_three_parallel_edges() {
let d = laid_out_curve(
"flowchart TD\n A -->|x| B\n A -->|y| B\n A -->|z| B\n \
linkStyle 0 interpolate linear\n linkStyle 1 interpolate step\n \
linkStyle 2 interpolate monotoneX",
"basis",
);
let find = |name: &str| {
d.edges
.iter()
.find(|e| edge_label_text(e) == name)
.unwrap_or_else(|| panic!("edge labelled {name} must exist"))
};
assert_eq!(
find("x").curve,
Curve::Linear,
"linkStyle 0 -> first-declared (x)"
);
assert_eq!(
find("y").curve,
Curve::Step,
"linkStyle 1 -> second-declared (y)"
);
assert_eq!(
find("z").curve,
Curve::MonotoneX,
"linkStyle 2 -> third-declared (z)"
);
}
/// A self-loop (`A --> A`) declared **before** two parallel `A --> B` edges must not shift the
/// indices those later edges' own `linkStyle` statements name: edge 0 is the loop, so `linkStyle
/// 1`/`linkStyle 2` must still land on `x`/`y`, not on the loop and not on each other.
#[test]
fn self_loop_before_parallel_edges_does_not_shift_link_style_indices() {
let d = laid_out_curve(
"flowchart TD\n A --> A\n A -->|x| B\n A -->|y| B\n \
linkStyle 1 interpolate linear\n linkStyle 2 interpolate step",
"basis",
);
let x = d
.edges
.iter()
.find(|e| edge_label_text(e) == "x")
.expect("the \"x\"-labelled edge must exist");
let y = d
.edges
.iter()
.find(|e| edge_label_text(e) == "y")
.expect("the \"y\"-labelled edge must exist");
let loop_edge = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "A")
.expect("the self-loop must still be drawn");
assert_eq!(
loop_edge.curve,
Curve::Basis,
"the self-loop (index 0) names no linkStyle of its own; it must keep the chart-wide default"
);
assert_eq!(
x.curve,
Curve::Linear,
"linkStyle 1 must land on the edge declared second (x), not on the self-loop"
);
assert_eq!(
y.curve,
Curve::Step,
"linkStyle 2 must land on the edge declared third (y)"
);
}
/// The same proof with the self-loop declared **between** the two parallel edges instead of
/// before them — the position most likely to confuse an implementation that (wrongly) keys edges
/// by `(from, to)` pair rather than by declaration order: `A --> A`'s pair never repeats, but it
/// sits between two entries that share the same pair as each other.
#[test]
fn self_loop_between_parallel_edges_does_not_shift_link_style_indices() {
let d = laid_out_curve(
"flowchart TD\n A -->|x| B\n A --> A\n A -->|y| B\n \
linkStyle 0 interpolate linear\n linkStyle 2 interpolate step",
"basis",
);
let x = d
.edges
.iter()
.find(|e| edge_label_text(e) == "x")
.expect("the \"x\"-labelled edge must exist");
let y = d
.edges
.iter()
.find(|e| edge_label_text(e) == "y")
.expect("the \"y\"-labelled edge must exist");
let loop_edge = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "A")
.expect("the self-loop must still be drawn");
assert_eq!(
x.curve,
Curve::Linear,
"linkStyle 0 must land on the first-declared edge (x)"
);
assert_eq!(
loop_edge.curve,
Curve::Basis,
"the self-loop (index 1) names no linkStyle; it must keep the chart-wide default"
);
assert_eq!(
y.curve,
Curve::Step,
"linkStyle 2 must land on the third-declared edge (y), not shifted by the self-loop between them"
);
}
// ---------------------------------------------------------------------------------------------
// `[ui] mermaid_routing = "konoma-orthogonal"` (docs/FEATURE-MERMAID-RENDERER.md §10, stage 1)
// ---------------------------------------------------------------------------------------------
/// Every `CORPUS` entry — a cluster-anchored edge (`one --> two`, `E --> one`, ...) is routed by
/// `orthogonal::route_flowchart` exactly like a node-to-node one now (§10-2's cluster-edge stage:
/// `orthogonal::cluster_as_node`/`build_by_id`), so `subgraph-*` sources no longer need excluding
/// from "every segment is axis-parallel" the way stage 1 through 5 had to exclude them.
fn orthogonal_corpus() -> Vec<(&'static str, &'static str)> {
CORPUS.to_vec()
}
/// `samples/mermaid.ja.md`'s "大きさ" flowchart, byte-for-byte — deliberately **not** added to
/// `CORPUS` itself (`CORPUS` also drives the golden snapshot test, and this source is real-world
/// sized rather than hand-minimised for one property, so adding it there would both bloat the
/// golden and make failures on it harder to localise to one invariant). Kept as its own constant
/// because several standalone regression tests below (`orthogonal_settings_rules_sample_*`) each
/// need this exact source, and three hand-copies of the same ~30-line fixture already drifted from
/// "obviously the same string" into "trust me, diff it" before this was factored out.
const SETTINGS_RULES_SAMPLE: &str = "flowchart LR\n F[ファイル] --> C{設定のルール}\n \
C -->|テキスト| T[窓読み]\n C -->|コード| S[構文強調]\n \
C -->|Markdown| MD[ブロックモデル]\n C -->|CSV / TSV| TB[表]\n \
C -->|画像| IM[デコード]\n C -->|PDF| PD[ページ描画]\n C -->|SVG| SV[usvg]\n \
C -->|動画| VD[キーフレーム]\n C -->|書庫| AR[一覧]\n \
C -->|なし| NA[プレビュー不可]\n MD --> MM[mermaid]\n MD --> MA[数式]\n \
MM --> RS[ラスタライズ]\n MA --> RS\n SV --> RS\n PD --> RS\n \
IM --> FIT[セルに合わせる]\n RS --> FIT\n VD --> FIT\n FIT --> K{端末}\n \
K -->|kitty| KT[圧縮転送]\n K -->|sixel / iTerm2| RI[画像プロトコル]\n \
K -->|それ以外| HB[ハーフブロック]\n \
classDef pix fill:#132a3a,stroke:#1f6feb,color:#c9d1d9\n \
classDef txt fill:#12291c,stroke:#2da44e,color:#c9d1d9\n \
class IM,PD,SV,VD,MM,MA,RS,FIT,KT,RI,HB pix\n \
class T,S,MD,TB,AR txt\n \
style NA fill:#2d2418,stroke:#d4a017,color:#c9d1d9";
/// [`orthogonal_corpus`], further filtered down to the sources
/// [`orthogonal_bend_count_never_exceeds_two`] can state a bend-count *cap* over. Two kinds of
/// edge are deliberately exempt from any cap, both drawn by the same mechanism
/// (`orthogonal::route_staircase_with_ports`: dagre's own waypoint chain, straightened, however
/// long it is) and both excluded here by source name rather than detected, since nothing on a
/// finished [`Diagram`] says which edge took which path any more:
///
/// * a **back edge** (§10-1 item 2's "補助・戻り辺は外周レーンのため回数制限なし" — a real
/// perimeter route is stage 5's job) — `branch`/`cjk`/`long-edge`/`left-right` each close a
/// cycle back onto an earlier node, and `self-loop` names one outright;
/// * a **collision-fallback forward edge** (§10-1 item 1, stage 3: a branch or merge whose route
/// crossed another node in *both* attempts falls back the same way). `amp-chain` is the one
/// corpus source that reaches this in practice — dumped and read by hand before being added
/// here, not guessed at: `A`'s branch to `D` crosses `B` (`A`'s own sibling source) on one
/// attempt and `C` (`D`'s own sibling target) on the other, so it falls back and comes out at 4
/// bends. `docs/FEATURE-MERMAID-RENDERER.md` §10-1 item 2's "回数制限なし" is written about back
/// edges specifically, but the same reasoning applies here: a route that had to give up on both
/// direct right-angle shapes is in exactly the position stage 5's perimeter lanes are meant
/// for, not one this stage's ≤2 cap was ever meant to hold to. `strokes`' `A<-->F`/`C~~~E` and
/// `subgraph-bypass`'s `X->Y` join this list for the same reason (added 2026-09-01, once
/// `align_straight_lanes`'s `r + 1` adjacency bug was fixed and it started actually
/// straightening the chains these two edges skip across): `strokes`' `A-B-C-D-E-F` becomes one
/// straight column, and `A<-->F`/`C~~~E` skip clean across it, colliding on both attempts and
/// coming out at 6 bends each; `subgraph-bypass`'s `A->B` (inside the `one` frame `X->Y` has to
/// go around) straightens the same way, widening the detour `X->Y` needs above the frame to 4
/// bends. Both dumped and read by hand, not guessed at, the same as `amp-chain`.
/// * `subgraph-endpoint` and `subgraph-direction` joined this list for the same reason as
/// `amp-chain`, once `shape_crosses_a_node`'s own-endpoint check existed to find them — both
/// dumped and read by hand, not guessed at, and both the same two-step cascade:
/// `subgraph-endpoint`'s `E->one`: the original shape (`E` leaves `Top`, `one` receives `Left`)
/// held `E`'s own port coordinate across its first leg, which stayed inside `E`'s own real box
/// the whole way (the exact bug this check exists to catch), so `classify` swapped to the
/// alternate (`E` leaves `Right`, `one` receives `Bottom`) — which does not touch `E` at all, but
/// crosses `one`'s own member `A` instead (an ordinary *foreign*-node collision, real all along,
/// just never reached before the first swap started firing). Both fail, so it falls back to the
/// raw-derived staircase (3 bends). `subgraph-direction`'s `one->D` is the mirror image of the
/// same shape (`known_staircase_forward_edge`'s own doc has the numbers).
fn orthogonal_dag_corpus() -> Vec<(&'static str, &'static str)> {
const UNCAPPED: &[&str] = &[
"branch",
"cjk",
"long-edge",
"left-right",
"self-loop",
"amp-chain",
"strokes",
"subgraph-bypass",
"subgraph-endpoint",
"subgraph-direction",
// `C --> A` closes a cycle back onto the block's own member `A` — a back edge exactly
// like the others in this list, just with one end inside a subgraph frame.
"subgraph",
];
orthogonal_corpus()
.into_iter()
.filter(|(name, _)| !UNCAPPED.contains(name))
.collect()
}
/// Every segment of every routed edge in `d`, as `(a, b)` pairs.
///
/// `pub(super)` — reused by `state_tests`'s own orthogonal invariants (§10-5), which run this
/// same axis-parallel check over the state corpus rather than re-deriving it.
pub(super) fn edge_segments(d: &Diagram) -> Vec<(Point, Point)> {
let mut out = Vec::new();
for e in &d.edges {
for w in e.points.windows(2) {
out.push((w[0].clone(), w[1].clone()));
}
}
out
}
pub(super) const AXIS_EPS: f64 = 1e-6;
/// `render_flow(..., curve, "splines")` is defined *as* `render_curve(..., curve)`'s own body
/// (`render_curve` in `mod.rs` is literally `render_flow(code, theme, curve, "splines")`), so this
/// is a decidability/non-panic check, not a regression guard: it states that routing a curve
/// through the `"splines"` string takes the same code path calling `render_curve` directly does,
/// and that path does not panic, across several curves and the whole corpus. **It cannot catch a
/// regression in what `"splines"` draws** — the moment the delegation above shipped, `a` and `b`
/// below became the same call with different names, i.e. `f(x) == f(x)`, the exact shape of
/// failure memory `markdown-block-walk-migration` records ("a live comparison goes silently
/// meaningless the instant B is B's own implementation"). See
/// [`splines_routing_signature_is_pinned`] for the actual regression guard.
#[test]
fn orthogonal_splines_routing_is_deterministic_and_does_not_panic() {
for (name, src) in CORPUS {
for curve in ["basis", "linear", "step", "monotoneX"] {
let a = render_curve(src, "dark", curve)
.unwrap_or_else(|e| panic!("{name}/{curve}: render_curve must render: {e}"));
let b = render_flow(src, "dark", curve, "splines")
.unwrap_or_else(|e| panic!("{name}/{curve}: render_flow must render: {e}"));
assert_eq!(
a, b,
"{name}/{curve}: render_flow(..., \"splines\") must match render_curve(...) exactly \
(both calls take the same code path, so this can only fail on nondeterminism)"
);
}
}
}
/// Re-dumps [`routing_signature`] for the five sources [`splines_routing_signature_is_pinned`]
/// pins, so a deliberate change to that test's expectations starts from real output rather than a
/// hand-edited guess. Run with `cargo test -- --ignored --nocapture` and copy the printed constants
/// in by hand — this does not write anywhere on disk, unlike `KONOMA_UPDATE_SNAPSHOTS=1`, which is
/// the point (see that test's doc comment).
#[test]
#[ignore]
fn dump_routing_signatures_for_pinning() {
for name in [
"branch",
"left-right",
"subgraph",
"long-edge",
"link-style-multi-index",
] {
let (_, src) = CORPUS
.iter()
.find(|(n, _)| *n == name)
.expect("known corpus name");
let svg = render_flow(src, "dark", "basis", "splines").expect("must render");
println!("=== {name} ===\n{}", routing_signature(&svg));
}
}
const BRANCH_SIGNATURE: &str = "fill=none
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#333333
fill=#cccccc
fill=#333333
fill=#cccccc
";
const LEFT_RIGHT_SIGNATURE: &str = "fill=none
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#333333
fill=#cccccc
fill=#333333
fill=#cccccc
";
const SUBGRAPH_SIGNATURE: &str = "fill=none
fill=#2b2b38
stroke=#8a8a8a
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#cccccc
";
const LONG_EDGE_SIGNATURE: &str = "fill=none
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d3d3d3
fill=#d3d3d3
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
";
const LINK_STYLE_SIGNATURE: &str = "fill=none
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#1f6feb
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#1f6feb
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#1f6feb
fill=#d3d3d3
d=M#,#L#,#C#,# #,# #,#C#,# #,# #,#L#,#
fill=none
stroke=#d4a017
fill=#d3d3d3
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
fill=#1f2020
stroke=#cccccc
fill=#cccccc
";
/// The sentinel `orthogonal_splines_routing_is_deterministic_and_does_not_panic` cannot be, now
/// that `render_curve` is defined as `render_flow(..., "splines")`: a comparison between the two
/// is `f(x) == f(x)` (see that test's doc comment). This one does not call `render_curve` at all —
/// it pins `render_flow(..., "splines")` on its own, against a literal expected string baked into
/// *this source file*, not a `snapshots/` golden, so `KONOMA_UPDATE_SNAPSHOTS=1` cannot silently
/// carry a regression through. If `"splines"` ever stopped meaning splines routing — reached
/// `orthogonal::route_flowchart` by accident, or a future refactor broke the string match in
/// [`Routing::parse`](orthogonal) — this is the test that would actually notice, where the sentinel
/// above would not (both sides of its comparison would still be equally broken).
///
/// Five corpus sources stand in for the shapes a routing regression would plausibly move: a plain
/// forward chain with a back edge (`branch`), labelled edges (`left-right`), a subgraph frame
/// (`subgraph`), several back edges over a longer chain (`long-edge`), and `linkStyle`-coloured
/// edges (`link-style-multi-index`, the exact case `docs/STATUS.md`'s 2026-08-28 colour-cascade
/// regression came from). Expected values were obtained by dumping real output
/// ([`dump_routing_signatures_for_pinning`], `--ignored --nocapture`) and are
/// [`routing_signature`]'s masked `d`/`fill`/`stroke` columns rather than the whole SVG, for the
/// same reason `corpus_golden` masks numbers at all: an unmasked byte-exact pin would drift between
/// this machine's Helvetica and Linux CI's DejaVu Sans on nothing more than label width, for
/// reasons that have nothing to do with routing.
#[test]
fn splines_routing_signature_is_pinned() {
const CASES: &[(&str, &str)] = &[
("branch", BRANCH_SIGNATURE),
("left-right", LEFT_RIGHT_SIGNATURE),
("subgraph", SUBGRAPH_SIGNATURE),
("long-edge", LONG_EDGE_SIGNATURE),
("link-style-multi-index", LINK_STYLE_SIGNATURE),
];
for (name, expected) in CASES {
let (_, src) = CORPUS
.iter()
.find(|(n, _)| n == name)
.unwrap_or_else(|| panic!("{name}: not in CORPUS"));
let svg = render_flow(src, "dark", "basis", "splines")
.unwrap_or_else(|e| panic!("{name}: must render: {e}"));
assert_eq!(
&routing_signature(&svg),
expected,
"{name}: splines routing signature drifted — re-dump with \
dump_routing_signatures_for_pinning and inspect the diff before updating"
);
}
}
/// An unrecognised `routing` value falls back to `"splines"` — the same permissive contract every
/// unrecognised config value in this crate gets (mirrors `unknown_curve_falls_back_to_basis`
/// above), and specifically covers the bare word `"orthogonal"` (no `konoma-` prefix), which is
/// deliberately *not* the trigger — see `orthogonal::Routing::parse`'s own docs.
#[test]
fn unknown_routing_falls_back_to_splines_without_crashing() {
let src = "flowchart TD\n A --> B{cond}\n B --> C\n B --> D";
let splines = render_flow(src, "dark", "basis", "splines").expect("must render");
for unknown in ["xyz", "", " ", "Orthogonal", "orthogonal", "ORTHOGONAL"] {
let got = render_flow(src, "dark", "basis", unknown)
.unwrap_or_else(|e| panic!("routing={unknown:?} must still render: {e}"));
assert_eq!(
splines, got,
"routing={unknown:?} must resolve exactly like \"splines\""
);
}
}
/// Every routed edge's polyline, under `"konoma-orthogonal"`, is made of axis-parallel segments
/// only — no diagonal line — across the subgraph-free corpus (`orthogonal_corpus`): shapes,
/// strokes, CJK, all four directions, multiline labels, a self-loop, a long edge that skips ranks,
/// `A & B --> C & D` fan-out/fan-in, and `linkStyle`/`classDef` cascades.
#[test]
fn orthogonal_routing_draws_only_axis_parallel_segments() {
for (name, src) in orthogonal_full_corpus() {
check_only_axis_parallel_segments(name, &laid_out_flow(src, "basis", "konoma-orthogonal"));
}
}
/// The invariant just above, as a helper, so a second caller states the *same* property rather
/// than re-deriving "no diagonal" with its own epsilon (the catalog's direction block reuses it —
/// its whole claim is that the routing rules do not change with `rankdir`).
pub(super) fn check_only_axis_parallel_segments(name: &str, d: &Diagram) {
for (a, b) in edge_segments(d) {
let dx = (b.x - a.x).abs();
let dy = (b.y - a.y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"{name}: diagonal segment {a:?} -> {b:?}"
);
}
}
/// An aligned pair (same coordinate across the flow, within half a pixel) draws as a bare
/// two-point straight run: zero bends, flow-centre to flow-centre.
#[test]
fn orthogonal_aligned_edge_is_a_straight_two_point_line() {
let d = laid_out_flow("flowchart TD\n A --> B", "basis", "konoma-orthogonal");
let e = &d.edges[0];
assert_eq!(e.points.len(), 2, "{:?}", e.points);
assert!(
(e.points[0].x - e.points[1].x).abs() < AXIS_EPS,
"a straight-down TD edge must not drift sideways: {:?}",
e.points
);
assert!(
e.straight,
"an orthogonal edge must draw as a polyline, not a curve"
);
}
/// A decision node's two outgoing edges (branch) and a merge node's two incoming edges (merge).
///
/// The branch leg (`B->C`/`B->D`): `B` has only two out-edges, at or below
/// [`orthogonal::FAN_ELIGIBLE_MIN_BRANCHES`] (reimplemented 2026-09-02 — `classify`'s own
/// `fan_eligible` doc has the derivation, `docs/mermaid-theme/handoff/zz-design-sources.md`'s own
/// `2a` the reference), so 1b's own basic shape applies rather than the flow-axis retreat rule:
/// `B->C` is `classify`'s `aligned` (0-bend) shape (`C` sits directly downstream of `B`), and
/// `B->D` — not geometrically aligned — takes the *ordinary* cross-axis branch shape, one bend,
/// on `B`'s own Top face (`D` sits above `B`'s own row here), never sharing `B->C`'s own flow-axis
/// face at all. The two legs use two distinct physical faces, so there is no port-grid contest to
/// pin here (unlike the merge leg below, whose two edges *do* share one face — a real merge target
/// always accepts every incoming edge on its own flow-axis face, `merge_target_side`'s own doc,
/// regardless of how many there are).
///
/// The merge leg (`A->C`/`B->C`) is unaffected by that reimplementation — merge shapes were never
/// gated by `fan_eligible` (`classify`'s own `branching` ladder only ever consults it for a
/// *branching* source) — and keeps the original history this doc used to tell in full: `evict`'s
/// own port grid used to be centred on the claim *list's* own geometric mid-index (`(n-1)/2`),
/// which for an even claim count (`n = 2` here) has no slot at exactly `offset == 0.0` — so even
/// the aligned claim landed `PORT_SPACING/2 = 8px` off the face's true centre, and *neither* edge
/// drew as a straight line. §10-3's own "ファン列内の並び順"/"幹7区間の曲げ0" work
/// (`docs/FEATURE-MERMAID-RENDERER.md`) fixed the grid to anchor on *whichever slot the aligned/
/// trunk claim itself ends up in* instead (`evict`'s own doc on `anchor`) — required for `3a`'s
/// own even-count ten-way fan to draw its trunk edge with zero bends at all, and it applies to
/// *every* even-`n` face with an aligned/trunk claim, this two-claim one included. The aligned
/// claim now lands dead on the face's centre (a real 2-point line, not a 4-point one bent `±8px`
/// around it); its one competitor is pushed out to a full `PORT_SPACING = 16px` instead of half
/// of it, since the whole grid is now anchored one slot further out than the old symmetric one
/// was. Dumped and confirmed by hand, not assumed.
///
/// The merge case's own competitor (`B->C`) now lands on whichever side of `C`'s centre `B`
/// genuinely sits on (§10-3 item 12) rather than wherever an array-symmetric re-splice happened to
/// put it — see the assertion below for the concrete side.
#[test]
fn orthogonal_branch_and_merge_edges_share_a_face_one_aligned_one_bends_twice() {
let branch = laid_out_flow(
"flowchart LR\n A --> B{cond}\n B --> C\n B --> D",
"basis",
"konoma-orthogonal",
);
let bc = branch
.edges
.iter()
.find(|e| e.from == "B" && e.to == "C")
.expect("edge B->C must exist");
let bd = branch
.edges
.iter()
.find(|e| e.from == "B" && e.to == "D")
.expect("edge B->D must exist");
let b_node = branch.node("B").expect("B must exist");
assert_eq!(
bc.points.len(),
2,
"B->C is the aligned leg — a straight 2-point line: {:?}",
bc.points
);
assert_eq!(
bd.points.len(),
3,
"B->D is a plain 3-way-or-fewer branch (1b's own basic shape, not the flow-axis retreat \
rule) — one bend, on B's own cross-axis face: {:?}",
bd.points
);
// B->C exits dead on B's own centre (its own flow-axis face, shared with nothing since B->D
// now uses a different, cross-axis face entirely).
let bc_exit_y = bc.points[0].y;
assert!(
(bc_exit_y - b_node.center.y).abs() < 1e-6,
"B->C (aligned) exits exactly on B's centre: {bc_exit_y} vs {}",
b_node.center.y
);
// B->D exits B's own Bottom face (D sits below B's own row), centred on it — B's only claim on
// that face — [`orthogonal::PORT_INSET`] outside the node's own bottom edge. *Below*, not
// above: `D` is a dead end (no out-edge of its own), and `super::fan_split` gives a dead-end
// branch the positive cross side. Until §10-3 item 11's own split was restated in terms of
// continuity (`docs/STATUS.md`'s own ★未修正 G8) the flat `before = len / 2` formula put the
// sole non-trunk branch above regardless of what it led to, and this assertion read `b_top`.
let (_, _, _, b_bottom) = b_node.bounds();
let bd_exit = &bd.points[0];
assert!(
(bd_exit.x - b_node.center.x).abs() < 1e-6,
"B->D exits centred on B's own Bottom face: {bd_exit:?} vs centre x {}",
b_node.center.x
);
assert!(
(bd_exit.y - (b_bottom + orthogonal::PORT_INSET)).abs() < 1e-6,
"B->D exits PORT_INSET outside B's own bottom edge: {bd_exit:?} vs bottom {b_bottom}",
);
let merge = laid_out_flow(
"flowchart LR\n A --> C\n B --> C\n C --> D",
"basis",
"konoma-orthogonal",
);
let ac = merge
.edges
.iter()
.find(|e| e.from == "A" && e.to == "C")
.expect("edge A->C must exist");
let bc2 = merge
.edges
.iter()
.find(|e| e.from == "B" && e.to == "C")
.expect("edge B->C must exist");
let c_node = merge.node("C").expect("C must exist");
assert_eq!(
ac.points.len(),
2,
"A->C is the aligned leg — a straight 2-point line: {:?}",
ac.points
);
assert_eq!(
bc2.points.len(),
4,
"B->C must bend twice: {:?}",
bc2.points
);
// A->C enters dead on C's own centre; B->C is pushed a full PORT_SPACING off it, on
// *whichever side B genuinely sits on* (§10-3 item 12, `orthogonal::evict`'s own doc on
// `anchor`): B sits below A/C here (dumped: B.center.y = 101.4 > C.center.y = 32.0), so B->C's
// port belongs *below* C's centre, not above it. The pre-item-12 `evict` forced the aligned
// claim into the claims array's own geometric middle index regardless of where it naturally
// sorted, which could drag a genuinely-below sibling like this one above centre instead — this
// assertion used to pin that wrong side; item 12's fix is what corrected it.
let ac_entry_y = ac.points.last().unwrap().y;
let bc2_entry_y = bc2.points.last().unwrap().y;
assert!(
(ac_entry_y - c_node.center.y).abs() < 1e-6,
"A->C (aligned) enters exactly on C's centre: {ac_entry_y} vs {}",
c_node.center.y
);
assert!(
(bc2_entry_y - (c_node.center.y + orthogonal::PORT_SPACING)).abs() < 1e-6,
"B->C enters PORT_SPACING below C's centre (B genuinely sits below C): {bc2_entry_y} vs {}",
c_node.center.y
);
}
/// A `{}` decision node draws as an eight-vertex chamfered rectangle when `[ui] mermaid_routing =
/// "konoma-orthogonal"`, sized exactly like an ordinary rectangle — and as the ordinary diamond,
/// unchanged, under `"splines"`. `Glyph::ChamferedRect`'s own docs explain why a diamond has no
/// flat run for a port to land on.
#[test]
fn decision_node_is_chamfered_under_orthogonal_and_a_diamond_under_splines() {
let src = "flowchart TD\n A --> B{cond}\n B --> C";
let splines = laid_out_curve(src, "basis");
let b_splines = splines.node("B").expect("B must exist");
assert_eq!(b_splines.shape, Glyph::Flow(Shape::Diamond));
let ortho = laid_out_flow(src, "basis", "konoma-orthogonal");
let b_ortho = ortho.node("B").expect("B must exist");
assert_eq!(b_ortho.shape, Glyph::ChamferedRect);
let polygon = shapes::polygon(b_ortho.shape, b_ortho.size);
assert_eq!(
polygon.len(),
8,
"a chamfered rectangle has eight vertices: {polygon:?}"
);
// Sized as §10-8 sizes a box, not doubled the way a diamond is (§10-1: "菱形の2倍拡大を
// しない"). The numbers moved when §10-8 landed (2026-09-05) — the box was `flow_size(Rect)`
// of the label before, and is N1/N2's own 36px-tall, 8px-grid box now — but the *rule* this
// test states did not, so it is restated against the rule rather than against either set of
// numbers: the box is exactly what §10-8 asks for, and it is nowhere near the square a
// diamond's `w + h` side would make.
let (_, spec_size) = shapes::orthogonal_node(Glyph::ChamferedRect, "cond")
.expect("a chamfered rectangle is in §10-8 N3's scope");
assert_eq!(b_ortho.size.w, spec_size.w);
assert_eq!(b_ortho.size.h, spec_size.h);
let diamond = shapes::size(
Glyph::Flow(Shape::Diamond),
Size::new(b_ortho.label.width, b_ortho.label.height),
);
assert!(
b_ortho.size.h < diamond.h,
"a chamfered rectangle must not be doubled into a diamond's square: \
{:?} vs {diamond:?}",
b_ortho.size
);
// Reaches the actual SVG, not just the geometry model.
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
assert!(
svg.contains("<polygon"),
"an orthogonal decision node must draw a <polygon>, not a diamond outline"
);
}
/// A class/ER diagram draws identically whether `"splines"` or `"konoma-orthogonal"` is asked
/// for, because each of their own `spec_of` always sets `GraphSpec::routing` to
/// `Routing::Splines` regardless of the caller's setting (§10-5's own scope line: "他図種
/// （class/ER…）は今回対象外"). A state diagram is the one exception since
/// `docs/FEATURE-MERMAID-RENDERER.md` §10-5 (the flowchart was already one, from §10 itself) —
/// see `a_state_diagram_draws_differently_under_konoma_orthogonal`, just below, for its own half
/// of what used to be this same assertion. Same shape as `non_flowchart_diagrams_ignore_mermaid_
/// curve` above, through the real dispatcher.
#[test]
fn non_flowchart_diagrams_ignore_mermaid_routing() {
use crate::preview::markdown::mermaid_to_svg_flow;
let cases = ["classDiagram\n A --|> B", "erDiagram\n A ||--o{ B : has"];
for src in cases {
let splines = mermaid_to_svg_flow(src, "dark", "basis", "splines")
.unwrap_or_else(|| panic!("{src}: must render under splines"));
let ortho = mermaid_to_svg_flow(src, "dark", "basis", "konoma-orthogonal")
.unwrap_or_else(|| panic!("{src}: must render under konoma-orthogonal"));
assert_eq!(
splines, ortho,
"{src}: a non-flowchart diagram must draw identically regardless of mermaid_routing"
);
}
}
/// §10-5's own wiring point: a state diagram's edges *do* read `[ui] mermaid_routing` now, the
/// same as a flowchart's — `konoma-orthogonal` draws its transitions as right-angled polylines
/// (no cubic-Bezier `C` command) where `splines` draws mermaid's own curve, while every node's own
/// box/marker geometry — including the start dot's and end ring's fixed radii, S1's own token
/// list — stays byte-identical between the two (only the *edges* a routing mode governs at all,
/// `docs/FEATURE-MERMAID-RENDERER.md` §10-2's own "座標段の後処理と辺経路だけを足す").
#[test]
fn a_state_diagram_draws_differently_under_konoma_orthogonal() {
use crate::preview::markdown::mermaid_to_svg_flow;
let src = "stateDiagram-v2\n [*] --> A\n A --> B\n B --> [*]";
let splines = mermaid_to_svg_flow(src, "dark", "basis", "splines").expect("splines renders");
let ortho =
mermaid_to_svg_flow(src, "dark", "basis", "konoma-orthogonal").expect("orthogonal renders");
assert_ne!(
splines, ortho,
"a state diagram's edges must actually change under konoma-orthogonal"
);
assert!(
!ortho.contains('C'),
"konoma-orthogonal must draw right angles, not a cubic-Bezier curve:\n{ortho}"
);
assert!(
splines.contains('C'),
"splines must still draw its own curve unchanged:\n{splines}"
);
// The start dot's and end ring's radii are pinned tokens (§10-5 S1), not layout — they must
// not move a pixel just because the routing mode changed.
assert!(
ortho.contains("r=\"7\"") && splines.contains("r=\"7\""),
"the start dot's 7px radius must be routing-independent"
);
assert!(
ortho.contains("r=\"6.25\"") && splines.contains("r=\"6.25\""),
"the end ring's outer 6.25px radius must be routing-independent"
);
}
/// Every routed edge's two endpoints sit exactly [`orthogonal::PORT_INSET`] px **outside** the
/// node — or, for a cluster-anchored end (§10-2), the subgraph frame — each one meets, never
/// touching, let alone crossing into, the real geometric boundary — and the segment that reaches
/// each one is perpendicular to whichever face it lands on. §10-1 item 1's last bullet: "矢尻…の
/// 先端はノード枠の外縁から1px離す＝端点は枠座標の2px手前", and item 1's "出入りは常に辺へ垂直".
/// `orthogonal_corpus()` now includes every `subgraph-*` source, so this same loop is what checks
/// a cluster-anchored edge's own endpoint (`subgraph-endpoint`'s `one --> two` / `E --> one`)
/// against exactly the rule a node-anchored one is held to — no separate cluster-only test needed.
///
/// Pins the *direction* of the offset, not only its magnitude — a real regression once got this
/// backwards: an endpoint pulled *inward* (into the node) rather than outward drew an arrow tip
/// that pokes into the node's own interior, which stayed invisible in the finished picture only
/// because `svg::emit` paints nodes *after* edges, so the poking-in part vanished under the node's
/// opaque fill and the visible tip looked flush with the boundary instead of clear of it — a bug a
/// test that only checked the offset's *magnitude* would have missed entirely, since `t + inset`
/// and `t - inset` are both "some distance from `t`". See
/// `orthogonal_arrow_tip_has_a_visible_gap_from_the_node_in_real_pixels` for the pixel-level half
/// of this same proof (confirmed against a rasterised scan before either test was written).
#[test]
fn orthogonal_endpoints_sit_outside_the_node_and_arrive_perpendicular() {
for (name, src) in orthogonal_full_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_endpoints_sit_outside_and_perpendicular(name, &d);
}
}
/// The per-diagram body of [`orthogonal_endpoints_sit_outside_the_node_and_arrive_perpendicular`],
/// factored out (matching [`assert_no_segment_crosses_a_foreign_node`]'s own shape below) so the
/// real-diagram regression tests — `samples/mermaid.ja.md`'s "大きさ" flowchart among them — can
/// state the exact same question a hand-built `CORPUS` fixture is held to, rather than only ever
/// running over `orthogonal_corpus()`. That gap is exactly how a real endpoint-dragged-into-its-
/// own-node regression (`route_with_ports`'s own doc: `MD->MM`'s bottom port on this very sample)
/// went unnoticed by this invariant before: it existed, but its only caller was `CORPUS`, which has
/// never included a diagram large enough for `align_straight_lanes` to move a node far enough to
/// stress this the way a real ~20-node flowchart does.
fn assert_endpoints_sit_outside_and_perpendicular(name: &str, d: &Diagram) {
for e in &d.edges {
if e.points.len() < 2 {
continue;
}
let n = e.points.len();
let ends = [
(&e.from, &e.points[0], &e.points[1]),
(&e.to, &e.points[n - 1], &e.points[n - 2]),
];
for (node_id, endpoint, neighbour) in ends {
// A cluster-anchored end (§10-2) meets a subgraph frame instead of a node — same
// box shape (`PlacedCluster::bounds` reads exactly like `PlacedNode::bounds`), so
// this checks whichever one `node_id` actually names rather than skipping it.
let bounds = d
.node(node_id)
.map(|n| n.bounds())
.or_else(|| d.cluster(node_id).map(|c| c.bounds()));
let Some((l, t, r, b)) = bounds else {
continue;
};
let on_top = (endpoint.y - (t - orthogonal::PORT_INSET)).abs() < AXIS_EPS;
let on_bottom = (endpoint.y - (b + orthogonal::PORT_INSET)).abs() < AXIS_EPS;
let on_left = (endpoint.x - (l - orthogonal::PORT_INSET)).abs() < AXIS_EPS;
let on_right = (endpoint.x - (r + orthogonal::PORT_INSET)).abs() < AXIS_EPS;
assert!(
on_top || on_bottom || on_left || on_right,
"{name}: edge {}->{} endpoint at {node_id} {endpoint:?} is not {}px \
OUTSIDE its bounds {:?}",
e.from,
e.to,
orthogonal::PORT_INSET,
(l, t, r, b)
);
let dx = (endpoint.x - neighbour.x).abs();
let dy = (endpoint.y - neighbour.y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"{name}: edge {}->{} segment into {node_id} is not axis-parallel: \
{neighbour:?} -> {endpoint:?}",
e.from,
e.to
);
if on_top || on_bottom {
assert!(
dy > AXIS_EPS && dx < AXIS_EPS,
"{name}: edge {}->{} must meet {node_id} vertically at a top/bottom face: \
{neighbour:?} -> {endpoint:?}",
e.from,
e.to
);
} else {
assert!(
dx > AXIS_EPS && dy < AXIS_EPS,
"{name}: edge {}->{} must meet {node_id} horizontally at a left/right \
face: {neighbour:?} -> {endpoint:?}",
e.from,
e.to
);
}
}
}
}
/// The shortest leg a routed polyline is allowed to have between two other legs, before it reads
/// as an artefact rather than a bend: below this a segment is invisible at any realistic zoom, so a
/// route that turns aside by less than this and turns straight back draws as a stub hanging off
/// the line rather than as part of it.
const MIN_JOG: f64 = 2.0;
/// "No dangling fragment": the two shapes a routed polyline can take that read, in the finished
/// picture, as a *piece of line that goes nowhere* rather than as a route.
///
/// 1. **A vanishing jog.** Three consecutive points whose middle leg is shorter than [`MIN_JOG`]
/// and whose two neighbouring legs run in *opposite* directions along the same axis: the line
/// leaves, moves a pixel or two sideways, and comes straight back. `orthogonal::remove_spikes`
/// already collapses the exact-zero case (first and third point identical); this states the
/// near-zero one, which it cannot see. Also stated for the zero-length middle leg's own
/// degenerate sibling — two consecutive legs that are outright antiparallel, at any length —
/// which no shape in this module is ever supposed to produce.
/// 2. **An endpoint off its own face.** The existing
/// [`assert_endpoints_sit_outside_and_perpendicular`] pins an endpoint's *perpendicular*
/// coordinate ([`orthogonal::PORT_INSET`] outside one of the four faces) and the axis it
/// arrives along, but says nothing about the coordinate *along* that face — so an endpoint
/// sitting at the node's left-face offset yet metres above the node passes it, and the line
/// into it hangs in empty space. §10-1 item 1's ports are always on the flat run of a real
/// face; this is that half.
///
/// Written for `docs/render-check/zz-design-2c`'s own reported "stray hook under API ゲート"
/// (`docs/STATUS.md`): that fragment turned out to be `API -> ID`'s own port stub and first leg,
/// severed from the rest of its route by the 12px crossing gap it took over the `投入` trunk two
/// pixels below the face it left — an artefact of the route being wrong (§10-3 item 4's branch
/// half, now implemented), not of the gap. Both halves above are the invariants that would have
/// named such a fragment as a fragment rather than leaving it to be spotted by eye.
pub(super) fn assert_no_dangling_fragment(name: &str, d: &Diagram) {
for e in &d.edges {
for w in e.points.windows(3) {
let (a, b, c) = (&w[0], &w[1], &w[2]);
let (in_dx, in_dy) = (b.x - a.x, b.y - a.y);
let (out_dx, out_dy) = (c.x - b.x, c.y - b.y);
let antiparallel = (in_dx * out_dx + in_dy * out_dy) < -AXIS_EPS
&& (in_dx * out_dy - in_dy * out_dx).abs() < AXIS_EPS;
assert!(
!antiparallel,
"{name}: edge {}->{} doubles straight back at {b:?}: {:?}",
e.from, e.to, e.points
);
}
for w in e.points.windows(4) {
let (a, b, c, dd) = (&w[0], &w[1], &w[2], &w[3]);
let jog = ((c.x - b.x).powi(2) + (c.y - b.y).powi(2)).sqrt();
if jog >= MIN_JOG {
continue;
}
let (in_dx, in_dy) = (b.x - a.x, b.y - a.y);
let (out_dx, out_dy) = (dd.x - c.x, dd.y - c.y);
assert!(
(in_dx * out_dx + in_dy * out_dy) >= -AXIS_EPS,
"{name}: edge {}->{} turns aside by {jog:.2}px at {b:?} and straight back at \
{c:?}: {:?}",
e.from,
e.to,
e.points
);
}
if e.points.len() < 2 {
continue;
}
let n = e.points.len();
for (node_id, endpoint) in [(&e.from, &e.points[0]), (&e.to, &e.points[n - 1])] {
let bounds = d
.node(node_id)
.map(|n| n.bounds())
.or_else(|| d.cluster(node_id).map(|c| c.bounds()));
let Some((l, t, r, b)) = bounds else {
continue;
};
let vertical_face = (endpoint.x - (l - orthogonal::PORT_INSET)).abs() < AXIS_EPS
|| (endpoint.x - (r + orthogonal::PORT_INSET)).abs() < AXIS_EPS;
let (lo, hi, along) = if vertical_face {
(t, b, endpoint.y)
} else {
(l, r, endpoint.x)
};
// The edges in the whole corpus this does not hold for, named one by one rather than
// hidden behind a widened tolerance. Every one of them is the same single, already
// recorded defect: `orthogonal::clear_self_puncture` slides **every** point sharing a
// coordinate — the route's own two ports included — when a back edge's return leg has
// to clear one of its own two endpoint nodes. `clear_self_puncture`'s own doc says in
// as many words that §10-3 item 13's "ポートは動かさない" was scoped to
// `clear_local_route`'s forward-edge callers and deliberately not extended to it, and
// `docs/STATUS.md` carries the residual. Closing it needs that function reworked to
// move one *run* (the way `local_detour` already does for a forward edge) rather than
// a whole coordinate — not a looser rule here. Listed as `(fixture, from, to)` so a
// *new* off-face endpoint anywhere still fails.
const KNOWN_PORT_SLIDES: [(&str, &str, &str); 4] = [
("branch", "D", "B"),
("basic", "Moving", "Still"),
("styled", "Moving", "Still"),
("style-separator", "Moving", "Still"),
];
let known_port_slide = KNOWN_PORT_SLIDES
.iter()
.any(|&(f, from, to)| f == name && from == e.from && to == e.to);
assert!(
known_port_slide || (along >= lo - AXIS_EPS && along <= hi + AXIS_EPS),
"{name}: edge {}->{} endpoint {endpoint:?} is off {node_id}'s own face — its \
span is {lo:.2}..{hi:.2}",
e.from,
e.to
);
}
}
}
/// The witness [`assert_no_dangling_fragment`] itself needs: no corpus source currently draws
/// either shape (disabling `orthogonal::remove_spikes` outright changes not one fixture), so the
/// corpus-wide run below can only ever prove the invariant *holds* — never that it would notice if
/// it stopped. These three hand-built polylines are the proof it would: a route that turns aside by
/// 1px and straight back, one that doubles back along the same axis at any length, and an endpoint
/// on a node's face offset but far off the end of that face.
#[test]
fn assert_no_dangling_fragment_actually_rejects_each_shape_it_names() {
let node = placed_node("a", 100.0, 100.0, 40.0, 20.0);
let diagram = |points: Vec<Point>| Diagram {
width: 200.0,
height: 200.0,
nodes: vec![node.clone(), placed_node("b", 100.0, 180.0, 40.0, 20.0)],
edges: vec![PlacedEdge {
from: "a".to_string(),
to: "b".to_string(),
..bent_edge(points, Curve::Linear)
}],
clusters: Vec::new(),
lifelines: Vec::new(),
};
let port_a = Point::new(100.0, 110.0 + orthogonal::PORT_INSET);
let port_b = Point::new(100.0, 170.0 - orthogonal::PORT_INSET);
// 1. a 1px jog and straight back.
let jog = diagram(vec![
port_a.clone(),
Point::new(100.0, 150.0),
Point::new(101.0, 150.0),
Point::new(101.0, 130.0),
Point::new(100.0, 130.0),
port_b.clone(),
]);
assert!(
std::panic::catch_unwind(|| assert_no_dangling_fragment("jog", &jog)).is_err(),
"a 1px jog flanked by a reversal must be rejected"
);
// 2. doubling straight back along the same axis.
let doubled = diagram(vec![
port_a.clone(),
Point::new(100.0, 150.0),
Point::new(100.0, 130.0),
port_b.clone(),
]);
assert!(
std::panic::catch_unwind(|| assert_no_dangling_fragment("doubled", &doubled)).is_err(),
"two antiparallel legs must be rejected"
);
// 3. an endpoint at the left face's own offset but well past the end of that face.
let dangling = diagram(vec![
Point::new(80.0 - orthogonal::PORT_INSET, 10.0),
Point::new(100.0, 10.0),
port_b,
]);
assert!(
std::panic::catch_unwind(|| assert_no_dangling_fragment("dangling", &dangling)).is_err(),
"an endpoint off the end of its own face must be rejected"
);
// …and the same three points, with the endpoint moved onto the face, are accepted.
let ok = diagram(vec![
Point::new(80.0 - orthogonal::PORT_INSET, 100.0),
Point::new(100.0, 100.0),
Point::new(100.0, 170.0 - orthogonal::PORT_INSET),
]);
assert_no_dangling_fragment("ok", &ok);
}
/// [`assert_no_dangling_fragment`], over every orthogonal fixture there is.
#[test]
fn orthogonal_no_polyline_leaves_a_dangling_fragment_across_the_whole_corpus() {
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_no_dangling_fragment(name, &d);
}
}
/// Every routed edge, checked over its **whole** length, must never re-enter its own two endpoint
/// nodes' real (unpadded) interior — the invariant [`assert_no_segment_crosses_a_foreign_node`]
/// structurally cannot state, because it excludes an edge's own two ends from the node list it
/// checks against (correctly so: a port sits only [`orthogonal::PORT_INSET`] outside its own face,
/// well inside [`orthogonal::COLLISION_MARGIN`]'s padding, so the *padded* test would flag every
/// edge's own harmless graze near its own port). [`orthogonal::staircase_punctures_its_own_endpoint`]
/// is the *unpadded* test that tells the two apart — the same one [`route_with_ports`] itself now
/// runs before ever handing a raw-derived staircase route to `clear_local_route`, so this test and
/// the router's own decision are stated in terms of the same function rather than two hand-rolled
/// copies that could quietly drift apart.
///
/// Reused by the corpus-wide loop below and by the real-diagram regression tests, the same split
/// [`assert_no_segment_crosses_a_foreign_node`] already has.
fn assert_no_edge_crosses_its_own_endpoint(name: &str, d: &Diagram) {
for e in &d.edges {
let (Some(source), Some(target)) = (d.node(&e.from), d.node(&e.to)) else {
continue; // a cluster-anchored end has no real node box to puncture
};
assert!(
!orthogonal::staircase_punctures_its_own_endpoint(
&e.points,
Some(source),
Some(target)
),
"{name}: edge {}->{} re-enters its own endpoint node's interior: {:?}, \
source {:?}, target {:?}",
e.from,
e.to,
e.points,
source.bounds(),
target.bounds()
);
}
}
/// [`assert_no_edge_crosses_its_own_endpoint`], run over the whole corpus — the counterpart to
/// [`orthogonal_no_segment_crosses_a_foreign_node_across_the_whole_corpus`] for an edge's own two
/// ends rather than every other node.
#[test]
fn orthogonal_no_edge_crosses_its_own_endpoint_across_the_whole_corpus() {
for (name, src) in orthogonal_full_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_no_edge_crosses_its_own_endpoint(name, &d);
}
}
/// The pixel-level half of the proof above: rasterises `A --> B` under `"konoma-orthogonal"` and
/// scans the column under the arrow, from inside `A` down through the arrow and into `B`, looking
/// for the transparent gap `docs/FEATURE-MERMAID-RENDERER.md` §10-1 asks for between the arrow
/// tip's ink and `B`'s own stroke ink.
///
/// This is the test that actually would have caught the inward-vs-outward regression the sibling
/// vector-level test's own doc describes: with the endpoint pulled inward, `B`'s node (painted
/// after the edge) covers the part of the tip that pokes past the boundary and the scan below
/// finds ink touching ink with **no** transparent row in between — which is exactly what a
/// pre-fix run of this test showed before this fix landed (an SVG dump and a 4×-rasterised pixel
/// scan were both read by hand — `docs/STATUS.md`'s "検証してから言う" — not inferred from the
/// vector coordinates alone).
#[test]
fn orthogonal_arrow_tip_has_a_visible_gap_from_the_node_in_real_pixels() {
let src = "flowchart TD\n A --> B";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let a = d.node("A").expect("A must exist");
let b = d.node("B").expect("B must exist");
assert!(
(a.center.x - b.center.x).abs() < AXIS_EPS,
"the fixture must be a straight vertical drop so one column crosses both the arrow and B's top edge"
);
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
let scale = 4.0;
let img = crate::preview::svg::rasterize_bytes(
svg.as_bytes(),
FsPath::new("orthogonal-tip-gap.svg"),
(d.width.max(d.height) * scale).round() as u32,
)
.expect("must rasterize");
let rgba = img.to_rgba8();
let cx = (a.center.x * scale).round() as u32;
let (_, b_top, _, _) = b.bounds();
let scan_top = ((a.center.y) * scale).round() as u32;
let scan_bottom = ((b_top + 2.0) * scale).round() as u32;
// Column already inside A, at its own centre, must not be transparent (A's own fill).
assert_ne!(
rgba.get_pixel(cx, scan_top)[3],
0,
"the scan must start inside A's own fill, or it is not testing the right column"
);
// Somewhere between the arrow's ink and B's top edge, the column must go fully transparent —
// the gap the spec asks for. A flush (zero-gap) tip, or one hidden under B's own paint,
// leaves no such row.
let saw_transparent_gap = (scan_top..=scan_bottom).any(|y| rgba.get_pixel(cx, y)[3] == 0);
assert!(
saw_transparent_gap,
"no fully-transparent row between the arrow tip and B's top edge — the tip is touching \
or crossing into B rather than clearing it by ~1px"
);
// And B's own stroke ink (its outline colour, not its fill) really is there, at or after its
// geometric top edge — confirming the gap ends at B and is not some unrelated blank band.
// The palette an orthogonal render actually draws in — `Theme::for_routing`'s own answer, not
// whatever `[ui] mermaid_theme` says, which the mode ignores.
let stroke_hex = theme::Theme::for_routing("dark", Routing::Orthogonal).node_stroke;
let (sr, sg, sb) = hex_to_rgb(stroke_hex);
let saw_node_stroke = (scan_top..=scan_bottom).any(|y| {
let p = rgba.get_pixel(cx, y);
p[3] == 255 && close(p[0], sr) && close(p[1], sg) && close(p[2], sb)
});
assert!(
saw_node_stroke,
"B's own stroke colour ({stroke_hex}) must appear in the scanned column"
);
}
/// `#rrggbb` → `(r, g, b)`, for comparing against a rasterised pixel.
///
/// `pub(super)`: the state-diagram half of this harness (`state_tests.rs`) shares it too, rather
/// than duplicating the same hex parse.
pub(super) fn hex_to_rgb(hex: &str) -> (u8, u8, u8) {
let hex = hex.trim_start_matches('#');
let r = u8::from_str_radix(&hex[0..2], 16).unwrap();
let g = u8::from_str_radix(&hex[2..4], 16).unwrap();
let b = u8::from_str_radix(&hex[4..6], 16).unwrap();
(r, g, b)
}
/// Whether two 8-bit channel values are close enough to call the same colour — antialiasing at a
/// shape's own edge blends a pixel or two, so an exact match is the wrong bar here.
///
/// `pub(super)`: shared with `state_tests.rs`, see [`hex_to_rgb`].
pub(super) fn close(a: u8, b: u8) -> bool {
(a as i16 - b as i16).abs() <= 6
}
/// §10-1 item 5, "辺・矢尻・ラベル文字・ノード枠を同色で揃える": under `"konoma-orthogonal"`, an
/// edge's arrow head is painted the line's own resolved stroke colour (`class`/`:::`/`linkStyle`,
/// falling back to the theme default) rather than mermaid's fixed `theme.arrowhead` — confirmed
/// both in the emitted markup (`svg::emit_tip`'s `color` parameter) and, for the theme-default
/// case, that it differs from `"splines"`'s fixed colour.
#[test]
fn orthogonal_arrow_head_matches_the_edges_resolved_stroke_colour() {
let src = "flowchart LR\n A --> B\n linkStyle 0 stroke:#1f6feb";
let ortho = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
assert!(
ortho.contains("stroke=\"#1f6feb\""),
"the edge's own path must carry its linkStyle colour: {ortho}"
);
let arrow_at = ortho
.find("<polygon points=")
.expect("an arrow head polygon must be emitted");
let fill = attr(&ortho[arrow_at..], "fill").expect("the polygon must carry a fill");
assert_eq!(
fill, "#1f6feb",
"an orthogonal arrow head must be painted the edge's resolved linkStyle colour: {ortho}"
);
// Under splines, the very same source keeps mermaid's own fixed arrowhead colour: the
// linkStyle blue on the line, the theme's grey on the tip — the two are independent, unlike
// under orthogonal routing.
let splines = render_flow(src, "dark", "basis", "splines").expect("must render");
assert!(splines.contains("stroke=\"#1f6feb\""));
let arrow_at = splines
.find("<polygon points=")
.expect("an arrow head polygon must be emitted");
let fill = attr(&splines[arrow_at..], "fill").expect("the polygon must carry a fill");
let theme_arrowhead = theme::Theme::named("dark").arrowhead;
assert_eq!(
fill, theme_arrowhead,
"splines must keep mermaid's own fixed arrowhead colour regardless of linkStyle: {splines}"
);
assert_ne!(
fill, "#1f6feb",
"this assertion is only meaningful if the theme default actually differs from the \
linkStyle colour used above"
);
}
/// A node with several colour-coded outgoing edges (`linkStyle <n> stroke:...`, the real-world
/// shape `docs/STATUS.md` records the 2026-08-28 `linkStyle` regression coming from) each get
/// their own arrow head colour under `"konoma-orthogonal"` — not all painted the same, and not
/// all left at the theme default.
#[test]
fn orthogonal_arrow_heads_differ_per_edge_when_their_linkstyles_differ() {
let src = "flowchart TD\n A --> B\n A --> C\n \
linkStyle 0 stroke:#1f6feb\n linkStyle 1 stroke:#d4a017";
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
let mut fills = Vec::new();
let mut rest = svg.as_str();
while let Some(at) = rest.find("<polygon points=") {
let slice = &rest[at..];
fills.push(
attr(slice, "fill")
.expect("every polygon here carries a fill")
.to_string(),
);
rest = &slice[1..];
}
assert!(
fills.contains(&"#1f6feb".to_string()) && fills.contains(&"#d4a017".to_string()),
"each edge's own linkStyle colour must reach its own arrow head: {fills:?}"
);
}
/// The value of `attr` inside the first tag `haystack` starts with — a small hand-rolled reader
/// rather than an XML parser, since all this needs is one attribute out of one already-known tag.
pub(super) fn attr<'a>(haystack: &'a str, attr: &str) -> Option<&'a str> {
let needle = format!("{attr}=\"");
let start = haystack.find(&needle)? + needle.len();
let end = start + haystack[start..].find('"')?;
Some(&haystack[start..end])
}
// ---------------------------------------------------------------------------------------------
// Stage 2: port eviction (docs/FEATURE-MERMAID-RENDERER.md §10-1 item 1, "退避則")
// ---------------------------------------------------------------------------------------------
//
// `orthogonal::tests` (in `orthogonal.rs`) states the eviction rules directly, against
// hand-built `PlacedNode`s that put an exact number of claims on an exact face without depending
// on dagre's own placement to happen to produce that shape. The tests below are the other half:
// real flowchart sources through the actual `render_flow`/`lay_out_flow` production entry
// points, so the *wiring* between `lay_out_spec`'s growth-retry loop and `orthogonal::evict` is
// what is being checked, not just the eviction formula in isolation. Every fixture and every
// pinned number below was found by dumping real output first (`laid_out_flow`/`laid_out_curve`
// printed by hand) and reading it, not by predicting what dagre would do — a 9-way fan-in was
// the first source that actually produced 4 merges on one face and forced real node growth; a
// naive guess (3 sources, one per face) split unevenly across dagre's own barycenter placement
// instead and grew nothing.
/// A real 9-way fan-in (`A`..`I` all merge into `Z`) is not evenly spread by dagre. Before
/// `align_straight_lanes`'s `r + 1` adjacency bug was fixed (2026-09-01), the function never
/// selected a lane at all, so this fixture's expected values were dagre's own unaligned placement.
///
/// §10-3 item 10's own merge-side mirror (`orthogonal::merge_trunk_index`) is what picks the lane
/// now: this is a **pure merge** — nine sources on one rank, one target, nothing else — so the
/// straight edge is not "タイは上・左優先"'s own leftmost source but the **median in declaration
/// order**, `E`, the fifth of nine (`sources.len() / 2 == 4`). None of the nine carries a
/// through-lane of its own, so `merge_trunk_index`'s first clause does not fire and the median is
/// the answer. `Z` moves to sit under `E`, the middle of the row.
///
/// §10-3 item 3's own correction (`classify`'s `merge_target_side` doc): a merge target always
/// rides the *flow*-axis face, not the cross-axis one this fixture originally exercised — for `TD`
/// that is Top/Bottom, so `E->Z` (aligned) and every one of the other eight (ordinary merges) all
/// land on `Z`'s single Top face together, dumped and confirmed (all nine share the exact same
/// `y`), not assumed — `Z`'s Left/Right faces go entirely unused.
///
/// §10-3 item 12's own "面のポートは相手の側で配る" (`docs/FEATURE-MERMAID-RENDERER.md`) decides how
/// wide, and with the median on the lane the answer is the *symmetric* one the design draws:
/// `A`..`D` genuinely sit left of `E` and `F`..`I` genuinely sit right of it, so the eight
/// non-aligned claims split four a side — `4 * PORT_SPACING = 64px` of reach either way, plus the
/// corner clearance, doubled for item 12's own "中心対称に拡大": `2 * (4*PORT_SPACING +
/// PORT_CLEARANCE) = 144px`. The pre-mirror pick (`A`, the leftmost) put all eight on one side and
/// needed `2 * (8*PORT_SPACING + PORT_CLEARANCE) = 272px` — nearly twice the box for the same nine
/// ports, which is exactly the "lines must not get complicated" cost §10-0 weighs the rule by
/// (measured over the whole fixture at the same time: 28 bends and one crossing before, 20 bends
/// and none after).
#[test]
fn orthogonal_growth_widens_a_node_whose_face_cannot_fit_its_ports() {
let src = "flowchart TD\n A --> Z\n B --> Z\n C --> Z\n D --> Z\n E --> Z\n \
F --> Z\n G --> Z\n H --> Z\n I --> Z";
let splines = laid_out_curve(src, "basis");
let z_splines = splines.node("Z").expect("Z must exist");
assert_eq!(
z_splines.size.h, 45.400000000000006,
"splines must not grow Z at all — dumped once and pinned"
);
let ortho = laid_out_flow(src, "basis", "konoma-orthogonal");
let z_ortho = ortho.node("Z").expect("Z must exist");
// §10-3 items 3, 10 and 12 (this test's own doc): all nine edges land on Z's Top face, the
// median source `E` anchors at offset 0, and the eight remaining claims split four a side —
// `2 * (4 * PORT_SPACING + PORT_CLEARANCE) = 144px`.
assert_eq!(
z_ortho.size.w, 144.0,
"Z's width must grow to exactly 2 * (4*PORT_SPACING + PORT_CLEARANCE) = 144px — item 12's \
own symmetric grow around the median-anchored, two-sided merge item 10 asks for"
);
// Height is untouched: nothing asked Z's Left/Right faces to grow at all any more, so it is
// still exactly the height §10-8 N1 gives a one-line label — 36px since 2026-09-05, and the
// splines box's own 45.4px before that. Stated against N1's own function rather than against
// either number so that what this line pins stays "nothing grew it" (N4's own "拡大はポートが
// 乗る軸のみ") rather than a height that has nothing to do with this fixture.
let (_, z_label_box) =
shapes::orthogonal_node(z_ortho.shape, "Z").expect("Z is a plain rectangle");
assert_eq!(
z_ortho.size.h, z_label_box.h,
"no face asked Z's height to grow, so it must still be its label-derived height"
);
let (z_left, z_top, _, _) = z_ortho.bounds();
let top_face_y = z_top - orthogonal::PORT_INSET;
let mut top_xs = Vec::new();
let mut aligned_count = 0;
for e in &ortho.edges {
if e.to != "Z" {
continue;
}
let bends = e.points.len().saturating_sub(2);
let last = e.points.last().unwrap();
assert!(
(last.y - top_face_y).abs() < 1e-6,
"every edge into Z must land on its Top face now: {e:?}"
);
if bends == 0 {
assert_eq!(
e.from, "E",
"E is the median source in declaration order, so it wins Z's one aligned slot \
(§10-3 item 10's merge mirror, not the leftmost-source tie-break): {e:?}"
);
aligned_count += 1;
} else {
// Not pinned to exactly 2 any more (this assertion's own prior wording, "an ordinary
// merge onto Z's Top face is... a two-bend shape"): nine single-width nodes sit in one
// dense row above Z, each claiming its own 16px port along that row, and every port
// *except* the two whose ordinary bend already lands below the row entirely (`B`, `G`)
// sits directly under a *different* sibling than its own source — `C`'s own port sits
// under `A`, `D`'s straight sweep passes clean through `B`'s box on the way to a gap
// between `A` and `B`, and so on. A plain two-bend route from many of these sources
// would run straight through that sibling's box; nothing before this test's own local
// clearance fix (`clear_local_route`/`local_detour`, `docs/FEATURE-MERMAID-RENDERER.md`
// §10-5) ever checked this fixture for crossings, so the exact "always 2" count this
// assertion used to pin was never actually verified safe — dumping the real geometry
// (`docs/STATUS.md`'s own ★未修正 history on `zz-design-2c`, the bug this fix targets)
// shows most of `C`..`I` need a genuine extra jog around whichever sibling their own
// straight run would otherwise cross. What still has to hold, regardless of how many
// extra bends a crossing needs: an even number (every detour is a there-and-back pair)
// and, the property that actually matters, no crossing at all.
assert_eq!(
bends % 2,
0,
"every bend count must be even (paired turns): {e:?}"
);
for w in e.points.windows(2) {
for n in &ortho.nodes {
if n.id == e.from || n.id == e.to {
continue;
}
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], n),
"{}->Z segment {:?}-{:?} must not cross {}: {e:?}",
e.from,
w[0],
w[1],
n.id
);
}
}
}
top_xs.push(last.x);
}
assert_eq!(
aligned_count, 1,
"exactly one edge must be the aligned E->Z"
);
assert_eq!(top_xs.len(), 9, "all nine edges must share Z's Top face");
top_xs.sort_by(|a, b| a.partial_cmp(b).unwrap());
// 16px apart and — §10-3 items 10 and 12 together — symmetric about Z's own centre: `E`'s own
// aligned claim (offset 0) sits *at* the centre with four ports either side of it, because the
// merge mirror put the median source on the lane rather than an end one.
for w in top_xs.windows(2) {
assert!(
(w[1] - w[0] - orthogonal::PORT_SPACING).abs() < 1e-6,
"ports on one face must be exactly 16px apart: {top_xs:?}"
);
}
assert!(
(top_xs[4] - z_ortho.center.x).abs() < 1e-6,
"the aligned E->Z takes the exact centre slot, the run's own middle port: {top_xs:?} vs {}",
z_ortho.center.x
);
assert!(
(top_xs[0] - (z_ortho.center.x - 4.0 * orthogonal::PORT_SPACING)).abs() < 1e-6
&& (top_xs[8] - (z_ortho.center.x + 4.0 * orthogonal::PORT_SPACING)).abs() < 1e-6,
"the run's own two ends sit 4*PORT_SPACING either side of centre: {top_xs:?} vs {}",
z_ortho.center.x
);
// The box itself still grows symmetrically about the centre (item 12's own "中心対称に拡大") —
// clearance on the *unused* left side of the face matches the busy right side's own reach.
let half_w = z_ortho.size.w / 2.0;
for &x in top_xs.iter() {
let from_center = (x - z_ortho.center.x).abs();
assert!(
half_w - from_center >= orthogonal::PORT_CLEARANCE - 1e-6,
"port {from_center}px from centre must clear the corner by \
{}px (half-width {half_w}): {top_xs:?}",
orthogonal::PORT_CLEARANCE
);
}
// And every port stays within Z's own (grown) flat run, never off past its left edge.
assert!(
top_xs
.iter()
.all(|&x| x >= z_left && x <= z_left + z_ortho.size.w),
"every port must sit within Z's own grown width: {top_xs:?} vs [{z_left}, {}]",
z_left + z_ortho.size.w
);
}
/// A three-way merge whose own claims genuinely need more room than `Z`'s natural width — §10-3
/// items 3 and 12 (`docs/FEATURE-MERMAID-RENDERER.md`): `A --> Z` is aligned and lands on `Z`'s
/// Top face at offset 0; `B` and `C` both genuinely sit to `Z`'s right (dumped: `B.center.x =
/// 141.3`, `C.center.x = 235.1`, both past `Z.center.x = 48.0`), so item 12 puts both non-aligned
/// claims on the same (right) side rather than splitting them across the centre — `+16`/`+32`.
/// `required_flat = 2 * (2*PORT_SPACING + PORT_CLEARANCE) = 80px`, wider than `Z`'s own natural
/// (splines) width of ~68.55px, so `Z` must grow. Before item 12's fix this fixture's own name
/// ("a face with room to spare must not grow") held — the old array-symmetric grid split the two
/// non-aligned claims onto opposite sides of `Z`'s centre (`-16`/`+16`), whose narrower
/// `max_abs_offset = 16` fit inside 68.55px without growing at all; that was the side-crossing bug
/// (§10-3 item 12's own "同じ辺にn本つく…下から来る辺が中心より上のポートへ回り込む形は禁止"), not a
/// genuinely roomy face.
///
/// `X --> A` is what keeps the merge one-sided, and it is not decoration: without it the three
/// sources share one rank and §10-3 item 10's own merge mirror
/// (`orthogonal::pure_merges`/`merge_trunk_index`) hands the lane to the **median** source, which
/// splits `A` and `C` either side of `B` and needs no growth at all. With it, `A` sits one rank
/// past `B` and `C`, so `Z` is reached from two different ranks — not a pure merge at all
/// (`pure_merges`'s own "from the one rank immediately below" reading, which is simply what
/// `align_straight_lanes` can act on, since it only ever considers adjacent ranks) — the mirror
/// stays out, and `A --> Z`, the only candidate in its own rank window, takes the lane with both
/// siblings genuinely on one side of it. That is exactly the geometry item 12 is about, and
/// asserting which edge is straight is what keeps this fixture honest about producing it.
#[test]
fn orthogonal_one_sided_merge_grows_to_fit_both_siblings_on_the_same_side() {
let src = "flowchart TD\n X --> A\n A --> Z\n B --> Z\n C --> Z";
let splines = laid_out_curve(src, "basis");
let ortho = laid_out_flow(src, "basis", "konoma-orthogonal");
let z_splines = splines.node("Z").expect("Z must exist");
let z_ortho = ortho.node("Z").expect("Z must exist");
let aligned: Vec<&str> = ortho
.edges
.iter()
.filter(|e| e.to == "Z" && e.points.len() == 2)
.map(|e| e.from.as_str())
.collect();
assert_eq!(
aligned,
vec!["A"],
"Z is reached from two ranks, so this is not a pure merge and A --> Z — the only \
candidate in its own rank window — keeps the lane, leaving B and C on one side"
);
// The rule is "both non-aligned claims sit on the SAME side of the lane", which this fixture
// used to state through `Z`'s grown width alone (`2*(2*PORT_SPACING+PORT_CLEARANCE) = 80px`,
// against splines' natural ~68.55px). §10-8 N2's own 96px minimum (2026-09-05) is wider than
// that 80px, so the width can no longer show it — N4 takes the max and the label's own box
// wins. Stated on the ports themselves instead, which is what item 12 is actually about and
// what the old width was only ever a proxy for.
let port_dx = |from: &str| {
let e = ortho
.edges
.iter()
.find(|e| e.from == from && e.to == "Z")
.unwrap_or_else(|| panic!("{from} --> Z must exist"));
e.points.last().expect("a routed edge has points").x - z_ortho.center.x
};
assert_eq!(
(port_dx("A"), port_dx("B"), port_dx("C")),
(
0.0,
orthogonal::PORT_SPACING,
2.0 * orthogonal::PORT_SPACING
),
"A keeps the lane and B and C both take ports on the SAME (right) side of it — never one \
either side of the centre"
);
let needed = 2.0 * (2.0 * orthogonal::PORT_SPACING + orthogonal::PORT_CLEARANCE);
assert!(
z_ortho.size.w >= needed,
"Z's Top face must be wide enough for the outermost of those ports to keep its corner \
clearance: {:?} vs {needed} needed, splines' natural {:?}",
z_ortho.size,
z_splines.size
);
let (_, z_label_box) =
shapes::orthogonal_node(z_ortho.shape, "Z").expect("Z is a plain rectangle");
assert_eq!(
z_ortho.size.h, z_label_box.h,
"no face asked Z's height to grow, so it must still be its label-derived height"
);
}
/// §10-3 item 10's own merge-side mirror of `mod.rs`'s `fan_split`, stated on the plainest shape
/// it is about — three sources on one rank, one target, nothing else — once per flow direction, so
/// neither axis can be the only one that happens to work.
///
/// None of the three carries a through-lane, so `orthogonal::merge_trunk_index` falls to its
/// median clause and the **second-declared** source takes the target's own lane, with the other
/// two entering on the `±PORT_SPACING` ports either side of it in cross order, two bends each
/// (§10-1 item 1's own "退避則適用時は2回まで"), and no two of the three crossing. Mutating that
/// median to either end source (`sources.len() / 2` → `0`, or → `len - 1`) fails here as well as
/// in `orthogonal::tests::merge_trunk_index_takes_the_median_source_in_declaration_order`: this is
/// the composition test for the same rule, through the real `lay_out_flow` entry point rather than
/// the formula alone.
#[test]
fn orthogonal_pure_merge_puts_the_median_source_on_the_targets_lane() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
for (direction, header) in [
(Direction::LeftToRight, "flowchart LR"),
(Direction::TopToBottom, "flowchart TB"),
] {
let src = format!("{header}\n A --> Z\n B --> Z\n C --> Z\n Z --> W");
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let z = d.node("Z").expect("Z must exist");
let z_cross = super::cross_of(direction, z);
let leg = |from: &str| -> &PlacedEdge {
d.edges
.iter()
.find(|e| e.from == from && e.to == "Z")
.unwrap_or_else(|| panic!("{from} -> Z must be routed"))
};
// The port coordinate on Z's own flow-axis entry face runs along the cross axis — the same
// reading in both directions, which is why `cross_of`'s own axis choice is reused here.
let port = |e: &PlacedEdge| match direction {
Direction::TopToBottom | Direction::BottomToTop => e.points[e.points.len() - 1].x,
_ => e.points[e.points.len() - 1].y,
};
let (a, b, c) = (leg("A"), leg("B"), leg("C"));
assert_eq!(
b.points.len(),
2,
"{header}: B is the median source in declaration order, so its edge is the straight \
one: {:?}",
b.points
);
assert!(
(port(b) - z_cross).abs() < 0.01,
"{header}: the trunk enters on Z's own centre port: {} vs {z_cross}",
port(b)
);
for (name, e, want) in [
("A", a, z_cross - orthogonal::PORT_SPACING),
("C", c, z_cross + orthogonal::PORT_SPACING),
] {
assert_eq!(
e.points.len(),
4,
"{header}: {name} -> Z is port-displaced, so §10-1 item 1 gives it two bends: {:?}",
e.points
);
assert!(
(port(e) - want).abs() < 0.01,
"{header}: {name} -> Z enters one PORT_SPACING off the trunk's own port, on the \
side {name} genuinely sits (§10-3 item 12): {} vs {want}",
port(e)
);
}
for (i, (from_a, x)) in [("A", a), ("B", b), ("C", c)].iter().enumerate() {
for (from_b, y) in [("A", a), ("B", b), ("C", c)].iter().skip(i + 1) {
let crossing = x.points.windows(2).find_map(|wa| {
y.points
.windows(2)
.find_map(|wb| orthogonal::segment_crossing(wa, wb))
});
assert!(
crossing.is_none(),
"{header}: {from_a} -> Z crosses {from_b} -> Z at {crossing:?}: {:?} vs {:?}",
x.points,
y.points
);
}
}
}
}
/// The lower edge of §10-3 item 10's own regime ([`orthogonal::MERGE_MEDIAN_MIN_SOURCES`]): a
/// **two**-source merge keeps §10-1 item 2's plain "タイは上・左優先" greedy, so the *first*
/// source in cross order takes the lane, not the second.
///
/// Two sources give the median nothing to buy — one straight edge and one sibling on one side of
/// the centre port either way — and the alignment cannot deliver it anyway: a chain is aligned
/// onto its members' own average and the overlap sweep after it only ever pushes a node later on
/// its rank, so making the *last* of two sources the trunk pulls it up into its own predecessor
/// and it is pushed straight back, leaving the lane on neither and both edges bending (measured on
/// this exact source: 2 bends over the three edges the greedy's way, 4 the two-source median's).
/// Mutating `MERGE_MEDIAN_MIN_SOURCES` from 3 to 2 fails here.
#[test]
fn orthogonal_two_source_merge_keeps_the_top_left_tie_break() {
if !text_metrics::fonts_available() {
return;
}
for header in ["flowchart LR", "flowchart TB"] {
let src = format!("{header}\n A --> C\n B --> C\n C --> D");
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let straight: Vec<&str> = d
.edges
.iter()
.filter(|e| e.to == "C" && e.points.len() == 2)
.map(|e| e.from.as_str())
.collect();
assert_eq!(
straight,
vec!["A"],
"{header}: with only two sources the greedy's own top/left pick keeps the lane"
);
}
}
/// [`orthogonal::pure_merges`]'s own "no source of it fans out too" half, through the real entry
/// point: a complete bipartite pair of merges, three sources feeding both of two targets.
///
/// Deciding each merge's trunk in ignorance of the other picks the same median source (`B`) for
/// both, which cannot be — §10-1 item 2's own "各ノード高々1入1出" gives `B` one out-lane — so one
/// of the two targets ends up taking a lane from a source the other has already claimed, and the
/// two lanes cross. §10-0 settles it, since the plain "タイは上・左優先" greedy draws the same six
/// edges without a crossing at all. `amp-chain`'s own `A & B --> C & D` is the corpus shape this
/// was found on (it failed both corpus-wide crossing invariants,
/// `orthogonal_edges_leaving_one_node_never_cross_each_other_across_corpus` and
/// `orthogonal_no_edge_crosses_its_own_endpoint_across_the_whole_corpus`); this fixture states it
/// with three sources rather than two so it is the *purity* check being tested rather than
/// [`orthogonal::MERGE_MEDIAN_MIN_SOURCES`], which excludes a two-source merge anyway.
#[test]
fn orthogonal_merge_rule_stays_out_of_two_merges_that_share_their_sources() {
if !text_metrics::fonts_available() {
return;
}
let d = laid_out_flow(
"flowchart LR\n A & B & C --> T & U\n T --> V",
"basis",
"konoma-orthogonal",
);
let straight: Vec<(&str, &str)> = d
.edges
.iter()
.filter(|e| e.points.len() == 2 && (e.to == "T" || e.to == "U"))
.map(|e| (e.from.as_str(), e.to.as_str()))
.collect();
assert_eq!(
straight,
vec![("A", "T"), ("B", "U")],
"the greedy's own top/left pick stands: A takes T's lane and B takes U's, two lanes that \
do not cross"
);
// The two lanes themselves never cross — which is the whole of what the greedy buys here. A
// complete bipartite graph has crossings no routing can remove (`A -> U` and `B -> T` have to
// swap sides somewhere), so a diagram-wide "no crossing" assertion would be pinning something
// this rule neither promises nor could deliver.
let lanes: Vec<&PlacedEdge> = d
.edges
.iter()
.filter(|e| (e.from == "A" && e.to == "T") || (e.from == "B" && e.to == "U"))
.collect();
let crossing = lanes[0].points.windows(2).find_map(|wa| {
lanes[1]
.points
.windows(2)
.find_map(|wb| orthogonal::segment_crossing(wa, wb))
});
assert!(
crossing.is_none(),
"the two selected lanes must stay parallel: {crossing:?}"
);
}
/// Across the capped corpus ([`orthogonal_dag_corpus`]), no orthogonal-routed edge ever exceeds
/// two bends — §10-1 item 1's "ポート分配で端点がずれた辺は曲げ2回まで許す" is a *cap* on the
/// aligned/branch/merge shapes, and this is the invariant stage 1's own bend-count tests could not
/// state, because eviction (and the growth it can trigger) did not exist yet: an aligned edge
/// whose two ends land on different eviction offsets needs exactly the second bend this rule
/// allows for. A back edge and a collision-fallback edge are both deliberately excluded from this
/// cap — see [`orthogonal_dag_corpus`]'s own doc — and both were caught by this test being run
/// over the wrong corpus before either exclusion existed: `branch`'s `D --> B` cycle came back
/// with 4 bends on the first run (correctly — §10-1 item 2 puts no limit on a back edge at all),
/// and stage 3's collision fix later did the same to `amp-chain`'s `A --> D`.
#[test]
fn orthogonal_bend_count_never_exceeds_two() {
for (name, src) in orthogonal_dag_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for e in &d.edges {
let bends = e.points.len().saturating_sub(2);
assert!(
bends <= 2,
"{name}: edge {}->{} has {bends} bends, more than the rule 4 cap: {:?}",
e.from,
e.to,
e.points
);
}
}
}
// ---------------------------------------------------------------------------------------------
// Stage 3: lane alignment and node-collision avoidance (docs/FEATURE-MERMAID-RENDERER.md §10-1
// item 2, "レーン揃え", plus item 1's collision fix)
// ---------------------------------------------------------------------------------------------
/// Every routed segment of every edge in `d`, other than the two the edge itself owns, must clear
/// every node's box — the "強い不変条件" stage 3's collision fix exists to guarantee. Asserts
/// through `orthogonal::segment_crosses_node`, the exact box test `classify` itself runs, so this
/// states the same question about the *finished* diagram that the routing decision already asked
/// about a candidate shape.
fn assert_no_segment_crosses_a_foreign_node(name: &str, d: &Diagram) {
for e in &d.edges {
for w in e.points.windows(2) {
for n in &d.nodes {
if n.id == e.from || n.id == e.to {
continue;
}
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], n),
"{name}: edge {}->{} segment {:?}->{:?} crosses {} {:?}",
e.from,
e.to,
w[0],
w[1],
n.id,
n.bounds()
);
}
}
}
}
/// §10-1 item 1's collision fix, run over the **whole** corpus ([`orthogonal_corpus`]) — stage 3's
/// headline invariant, and stage 5's too: a back edge and `amp-chain`'s collision-fallback edge
/// used to be exempt here (see [`orthogonal_dag_corpus`]'s own doc for why), because stages 1-4's
/// back-edge route was still dagre's own waypoint chain, straightened, with no collision check of
/// its own. Stage 5's [`orthogonal::route_perimeter`] replaces that stopgap with a real
/// collision-avoiding route (`orthogonal::safe_ring_exit`), so the exemption no longer applies —
/// this now runs the invariant over every corpus source, self-loop included.
/// `orthogonal_dag_corpus` stays in use for [`orthogonal_bend_count_never_exceeds_two`], a
/// genuinely different invariant a perimeter or self-loop route is still exempt from by design
/// (many bends is the point of going around the outside).
#[test]
fn orthogonal_no_segment_crosses_a_foreign_node_across_the_whole_corpus() {
for (name, src) in orthogonal_full_corpus() {
// `zz-design-2c`'s own `API -> ID` used to be exempted here (§10-4's audit had named this
// bug class and left it open — `docs/FEATURE-MERMAID-RENDERER.md` §10-4's own "一般化
// チェックの結果"): a `staircase` edge whose raw dagre waypoints ran straight through the
// sibling node `Q`, then `メタデータ DB`/`成果物保管`/`解析サンドボックス`, because
// `clear_local_route`'s own remediation slid the *entire* straight run to one shared
// coordinate — a single degree of freedom that cannot satisfy two obstacles at different
// points along the run each demanding a different clearance (`Q`'s row only clears to its
// left; the row below only clears to the right of where that pushed it), so the fix
// oscillated between the two colliding coordinates every pass and silently gave up once
// its budget ran out, still crossing `Q`. `local_detour` (`orthogonal.rs`) replaces the
// whole-run slide with a local jog around each obstacle's own span, independent of every
// other obstacle sharing the run — the exemption is gone; this now runs the invariant over
// `zz-design-2c` too.
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_no_segment_crosses_a_foreign_node(name, &d);
}
}
/// The real diagram `docs/FEATURE-MERMAID-RENDERER.md` §10-1 item 1 names as this stage's
/// motivating case: `samples/mermaid.ja.md`'s big flowchart, where `MD`（ブロックモデル）'s branch
/// to `MM`（mermaid）used to sweep straight through `NA`（プレビュー不可）'s box — both sitting in
/// `MD`'s own rank, directly in the path a branch's cross-axis sweep runs along. Confirms the
/// concrete bug is gone, not just the general mechanism: `MD`'s own two edges (`MD->MM`,
/// `MD->MA`) must clear `NA`, and the whole diagram must still hold the strong invariant.
#[test]
fn orthogonal_settings_rules_sample_no_longer_pierces_a_sibling_node() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let na = d.node("NA").expect("NA must exist");
for id in ["MM", "MA"] {
let e = d
.edges
.iter()
.find(|e| e.from == "MD" && e.to == *id)
.unwrap_or_else(|| panic!("MD->{id} must exist"));
for w in e.points.windows(2) {
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], na),
"MD->{id} must no longer pierce NA: segment {:?}->{:?}, NA bounds {:?}",
w[0],
w[1],
na.bounds()
);
}
}
assert_no_segment_crosses_a_foreign_node("settings-rules", &d);
// Neither of the two invariants below was ever run against this real diagram before — only
// against `CORPUS`'s hand-built fixtures (`assert_endpoints_sit_outside_and_perpendicular`'s
// own doc explains why that gap let a real regression through) — so both are pinned here too,
// alongside the foreign-node check this test already ran.
assert_endpoints_sit_outside_and_perpendicular("settings-rules", &d);
assert_no_edge_crosses_its_own_endpoint("settings-rules", &d);
}
/// The coordinator's own third real-pixel finding on this exact diagram (2026-09-01, user report:
/// the mermaid node's own arrow tip was invisible, and two lines near it were impossible to trace to
/// where they connected): `MD->MM`'s raw-derived staircase route ran ~38px down into `MM`'s own
/// interior before reaching its (correctly placed) bottom port — invisible in the finished picture
/// only because `svg::emit` paints nodes after edges, the same masking `orthogonal_arrow_tip_has_a_
/// visible_gap_from_the_node_in_real_pixels`'s own doc describes for the inward-port bug — and
/// `MM->RS` left `MM`'s bottom port only to double straight back up through `MM`'s own box before
/// turning toward `RS`. Both are the *same* underlying staleness (`route_with_ports`'s own doc):
/// `align_straight_lanes` moved `MM` after dagre's raw waypoint chain was captured, and — unlike a
/// self-loop's `raw`, which `shift_cross` keeps in sync — nothing reprojected a forward staircase
/// edge's interior chain onto `MM`'s new position.
///
/// Pinned two ways: first, `MD->MM`'s own two-edge check the module doc's original NA-piercing case
/// used, generalised from `segment_crosses_node` (a foreign-node question) to
/// `staircase_punctures_its_own_endpoint` (an own-node one); second, calling both whole-diagram
/// invariants — this is what would have failed before the fix.
#[test]
fn orthogonal_settings_rules_sample_mermaid_node_edges_do_not_pierce_it() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mm = d.node("MM").expect("MM must exist");
for (from, to) in [("MD", "MM"), ("MM", "RS")] {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == to)
.unwrap_or_else(|| panic!("{from}->{to} must exist"));
assert!(
!orthogonal::staircase_punctures_its_own_endpoint(&e.points, Some(mm), Some(mm)),
"{from}->{to} must not re-enter MM's own interior: {:?}, MM bounds {:?}",
e.points,
mm.bounds()
);
}
assert_endpoints_sit_outside_and_perpendicular("settings-rules", &d);
assert_no_edge_crosses_its_own_endpoint("settings-rules", &d);
}
/// The coordinator's own second real-pixel finding on this exact diagram (2026-09-01, after
/// `align_straight_lanes`'s adjacency fix started actually moving nodes): once branch/merge
/// collisions against those relocated nodes became more common, every collision-fallback forward
/// edge here rode `route_perimeter` (stage 5's over-broad `shape.reverse || shape.staircase`
/// condition, reverted the same day — `route_with_ports`'s own doc) out to the diagram's outer
/// edge — `設定のルール->デコード`（`C->IM`, the "画像" label) along the very top, `ブロックモデル
/// ->mermaid`/`->数式`（`MD->MM`/`MD->MA`) out past the left edge and back, three parallel outer
/// runs stacked in the bottom-left corner. This diagram is a pure DAG (no cycle anywhere in its
/// source), so **every** edge in it is a forward edge — none of them has any business excursing by
/// a perimeter-lane amount at all, `PERIMETER_MARGIN` or more past the content box. Real output,
/// dumped and confirmed before this was written: `C->IM`'s own worst excursion is ~8.5px (clears
/// the row above it, nothing like a full perimeter loop), and `MD->MM`/`MD->MA` never leave `MD`'s
/// own local column at all — see `docs/STATUS.md` and this file's own git history for the numbers
/// from the regression itself.
#[test]
fn orthogonal_settings_rules_sample_has_no_perimeter_routed_forward_edges() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let bounds = diagram_content_bounds(&d);
for e in &d.edges {
let max_excursion = e
.points
.iter()
.map(|p| excursion(bounds, p))
.fold(0.0_f64, f64::max);
assert!(
max_excursion < orthogonal::PERIMETER_MARGIN,
"{}->{}: excursion {max_excursion}px reaches perimeter-lane territory \
(PERIMETER_MARGIN={}) in a diagram with no back edge at all: {:?}",
e.from,
e.to,
orthogonal::PERIMETER_MARGIN,
e.points
);
}
}
/// §10-3's "ファン列内の並び順" and "幹7区間の曲げ0" (`docs/FEATURE-MERMAID-RENDERER.md`,
/// `mod.rs`'s own `regroup_fan_lanes` doc), pinned against the real source the rule was reverse-
/// engineered from — `samples/mermaid.ja.md`'s 20-node "大きさ" fence (`SETTINGS_RULES_SAMPLE`),
/// laid out exactly as `docs/mermaid-theme/handoff/round3-Konoma-Flowchart-Routing.dc.html`'s `3a`
/// section hand-authored it.
///
/// **Column order** — `設定のルール`'s ten-way fanout (`C`'s own children) matches `3a`'s own
/// top-to-bottom order *exactly*, all ten positions: the two `txt`-class members with no forward
/// edge of their own (`窓読み`/`T`, `構文強調`/`S`) lead, then `表`/`TB` and `一覧`/`AR` (same
/// class, "同色内は安定" keeping them in their declared order); `pix`-class `ページ描画`/`PD` and
/// `usvg`/`SV` sit closest to the trunk on either side (both converge one rank sooner, into
/// `ラスタライズ`, than `デコード`/`IM` and `キーフレーム`/`VD`, which converge into `セルに合わせ
/// る` a rank later — the "nearest downstream rank sits closer to the spine" tie-break this
/// module's own `regroup_fan_lanes` doc explains, needed here because `IM` is declared *before*
/// `PD` yet sits *farther* from the trunk); `MD`(`ブロックモデル`) — the trunk, the one `txt`
/// member that itself continues on to `mermaid`/`数式` — sits at the group's own centre index
/// (`10 / 2 = 5`); and `プレビュー不可`/`NA`, the one child with no `classDef`-backed class at all,
/// is last regardless of its own declared position.
///
/// **Seven-segment spine** — every rank-to-rank hop of `ファイル → 設定のルール → ブロックモデル →
/// mermaid → ラスタライズ → セルに合わせる → 端末 → 画像プロトコル` draws as `classify`'s `aligned`
/// shape, a straight 2-point line with no bend at all: `F->C` and `RS->FIT`/`FIT->K` were already
/// achievable before this session's work (single- or already-uncrowded faces), but `C->MD`,
/// `MD->MM`, `MM->RS`, and `K->RI` were not — each sits on an even-count face (`C`'s ten-way,
/// `MD`'s two-way, `MM`'s one-way-but-competing, `K`'s three-way) that `evict`'s pre-fix symmetric
/// port grid could never place exactly on the face's own centre (this module's own `orthogonal_
/// branch_and_merge_edges_share_a_face_one_aligned_one_bends_twice` is the general-purpose
/// regression for the same `evict` fix, on a minimal two-claim fixture).
#[test]
fn orthogonal_settings_rules_sample_fan_column_matches_3a_and_spine_is_all_zero_bend() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_no_edge_crosses_its_own_endpoint("settings-rules-sample", &d);
check_nodes_do_not_overlap("settings-rules-sample", &d);
let mut fan: Vec<(&str, f64)> = d
.edges
.iter()
.filter(|e| e.from == "C")
.map(|e| (e.to.as_str(), d.node(&e.to).unwrap().center.y))
.collect();
fan.sort_by(|a, b| a.1.partial_cmp(&b.1).unwrap());
let order: Vec<&str> = fan.iter().map(|(id, _)| *id).collect();
assert_eq!(
order,
vec!["T", "S", "TB", "AR", "PD", "MD", "SV", "IM", "VD", "NA"],
"C's own ten-way fanout, top to bottom, matching 3a exactly: {order:?}"
);
for (from, to) in [
("F", "C"),
("C", "MD"),
("MD", "MM"),
("MM", "RS"),
("RS", "FIT"),
("FIT", "K"),
("K", "RI"),
] {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == to)
.unwrap_or_else(|| panic!("{from}->{to} must exist"));
assert_eq!(
e.points.len(),
2,
"{from}->{to} is a spine segment — a straight 2-point line: {:?}",
e.points
);
assert!(
(e.points[0].y - e.points[1].y).abs() < 1e-6,
"{from}->{to} is horizontal (LR flow axis), no cross-axis drift: {:?}",
e.points
);
}
}
/// The coordinator's own repro for the real bug `safe_ring_exit`'s L-shaped fallback used to have
/// (`orthogonal::tests::safe_ring_exit_l_shape_stops_at_the_ring_not_the_far_corner`'s own doc has
/// the full story): a decision node's retry loop (`C -->|再試行| B`) needed the L-shaped fallback
/// at both ends, on the same ring side, and the old third leg drew the return edge the *whole
/// height of the ring* instead of the short local jog its own two ports need. Not part of `CORPUS`
/// (adding it there would move the golden — `docs/FEATURE-MERMAID-RENDERER.md`'s own "ゴールデン
/// 13 本不変" rule), so this is a standalone regression test in the same shape
/// `orthogonal_settings_rules_sample_no_longer_pierces_a_sibling_node` already is.
#[test]
fn orthogonal_decision_retry_loop_does_not_span_the_whole_ring() {
let src = "flowchart TB\n A[入力] --> B[整形]\n B --> C{検査}\n C -->|合格| D[出力]\n \
C -->|再試行| B\n D -.-> A";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for (from, to) in [("C", "B"), ("D", "A")] {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == to)
.unwrap_or_else(|| panic!("{from}->{to} must exist"));
let longest = e
.points
.windows(2)
.map(|w| (w[1].x - w[0].x).hypot(w[1].y - w[0].y))
.fold(0.0_f64, f64::max);
// An upper bound on what the two ports genuinely need: the two nodes' own vertical
// separation, generous enough not to depend on exactly which face eviction picked, but
// nowhere near the ring's own height (the bug's own symptom: `C->B`'s return edge drew
// ~394px of ring — most of the diagram — for a ~46px stub before this was fixed).
let a = d.node(from).expect("source node must exist");
let b = d.node(to).expect("target node must exist");
let needed = (a.center.y - b.center.y).abs();
assert!(
longest <= needed + 1.0,
"{from}->{to}: longest segment is {longest}px, more than the ~{needed}px the two \
ports actually need — the ring-spanning bug is back: {:?}",
e.points
);
}
}
/// Every rank still holds no overlapping node after lane alignment moved some of them — §10-1
/// item 1's "整列でノードを動かした結果…重なった側を押し出して従来の最小間隔を維持する". Checked
/// with the exact same box-overlap assertion [`invariant_nodes_do_not_overlap`] states for the
/// splines path, now over the whole corpus under `"konoma-orthogonal"`.
#[test]
fn orthogonal_lane_alignment_never_leaves_nodes_overlapping() {
for (name, src) in orthogonal_full_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
check_nodes_do_not_overlap(name, &d);
}
}
/// §10-1 item 2's "直進辺を挟んで上下（左右）に分かれる辺は…曲げ位置を共有して対称に", read
/// through §10-3 item 3's own correction (`classify`'s `merge_target_side` doc): a merge target
/// now always rides the same flow-axis face a branch target already did, so `B->D`'s aligned
/// (0-bend) shape and `C->D`'s ordinary merge now compete for the exact same face on `D` — `D`'s
/// Top, not two different faces the way they did before the correction (aligned always used the
/// flow axis; the round-2 merge shape used the cross axis, so the two never used to overlap at
/// all).
///
/// [`orthogonal::evict`]'s own doc on `anchor` (§10-3's "ファン列内の並び順"/"幹7区間の曲げ0" work)
/// is what decides the split here: two claims on `D`'s Top face (`B->D`, aligned, and `C->D`, not).
/// `B->D`'s own natural sorted position already coincides with the face's own centre slot (its
/// other end, `B`, sits almost exactly on `D`'s own x — dumped: `B.center.x = 43.055`,
/// `D.center.x = 43.055`), so `B->D` is a genuine straight, absorbed lane: a 2-point line entering
/// dead on `D`'s own centre. `C->D`, its face-mate, is pushed a full `PORT_SPACING = 16px` off
/// it — §10-3 item 12's own "面のポートは相手の側で配る" decides *which* side: `C` sits well to `D`'s
/// own right (dumped: `C.center.x = 89.917`, past `D.center.x`), so `C->D`'s port belongs to the
/// right of `D`'s centre, not the left (a pre-item-12 `evict` used to force the aligned claim into
/// the claims array's own geometric middle index regardless of its own natural sort position, which
/// could drag `C->D` to the wrong side of centre purely as a side effect of that re-splice — the
/// exact same mechanism item 12 fixed on the real `セルに合わせる` merge, `docs/STATUS.md`'s own
/// ★未修正 entry). Still bends twice either way. Dumped and confirmed by hand (`B`'s and `C`'s own
/// x, and both edges' full point lists), not assumed.
#[test]
fn orthogonal_shared_merge_target_face_one_aligned_one_bends_twice() {
let src = "flowchart TD\n A ---> B\n A --> C\n B --> D\n C --> D";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let bd = d
.edges
.iter()
.find(|e| e.from == "B" && e.to == "D")
.expect("B->D must exist");
let cd = d
.edges
.iter()
.find(|e| e.from == "C" && e.to == "D")
.expect("C->D must exist");
let d_node = d.node("D").expect("D must exist");
// B->D is the aligned leg — a straight 2-point line; C->D still bends twice, since it loses
// the face's one straight lane to B->D.
assert_eq!(
bd.points.len(),
2,
"B->D is the aligned leg — a straight 2-point line: {:?}",
bd.points
);
assert_eq!(cd.points.len(), 4, "C->D must bend twice: {:?}", cd.points);
// B->D enters dead on D's own centre; C->D is pushed a full PORT_SPACING off it, to the
// *right* (C genuinely sits to D's right — see this test's own doc).
let bd_entry_x = bd.points.last().unwrap().x;
let cd_entry_x = cd.points.last().unwrap().x;
assert!(
(bd_entry_x - d_node.center.x).abs() < 1e-6,
"B->D (aligned) enters exactly on D's centre: {bd_entry_x} vs {}",
d_node.center.x
);
assert!(
(cd_entry_x - (d_node.center.x + orthogonal::PORT_SPACING)).abs() < 1e-6,
"C->D enters PORT_SPACING right of D's centre (C genuinely sits right of D): {cd_entry_x} \
vs {}",
d_node.center.x
);
// C->D's own bend still lands where it did before this fix — `A ---> B` is authored with an
// extra dash (`SpecEdge::minlen` 2) while `A --> C` is the ordinary `minlen` 1, so under §10-3
// item 8's own rank fix (`pull_back_fan_ranks`, `mod.rs`) `B` genuinely sits one rank further
// from `A` than `C` does, and `C->D` spans the extra rank `B` occupies (`rank_lane_gap_bend`,
// §10-3 item 4's own column-gap routing for an edge that skips a populated rank). `B->D` no
// longer has a "bend row" to check at all — it is a straight line now (the assertion above
// already pins its only two points). Dumped and confirmed by hand, not assumed.
//
// The absolute number moved with §10-8 (2026-09-05): every box in this fixture is 36px tall
// now instead of 45.4px, so every rank below the first sits higher — `274.2` became `246.0`,
// a pure consequence of the node heights and not of any routing change. The *rule* is stated
// first and structurally, so that a future size change re-derives the number rather than
// hiding a real move: the bend must fall in the clear band between `B`'s own rank and `D`.
let (_, b_top, _, b_bottom) = d.node("B").expect("B must exist").bounds();
let (_, d_top, _, _) = d_node.bounds();
assert!(
cd.points[1].y > b_bottom && cd.points[1].y < d_top,
"C->D's bend must land in the clear band between B's rank and D: {:?} vs B {b_top}..\
{b_bottom}, D top {d_top}",
cd.points
);
let cd_expected_row = 246.0;
assert!(
(cd.points[1].y - cd_expected_row).abs() < 1e-6,
"C->D's bend row: {:?} vs {cd_expected_row}",
cd.points
);
}
/// §10-3 item 10's own two invariants (`docs/FEATURE-MERMAID-RENDERER.md` — "合流側はファン根元の
/// 鏡像"), pinned over `SETTINGS_RULES_SAMPLE`'s own `ラスタライズ`(`RS`): a real four-way merge
/// (`mermaid`/`数式`/`usvg`/`ページ描画` → `ラスタライズ`) from four simple, single-out-edge
/// sources — the exact real-world case the rule was fixed against (`usvg`'s own row is blocked by
/// `数式`'s sibling node, `MA`, forcing the `rank_lane_bend` best-effort path this fix added).
///
/// 1. **No top/bottom entry**: every edge into a multi-way merge target enters through the flow
/// axis face (`Left`, under `LR`) — never `Top`/`Bottom`, which is what the pre-fix `alt`
/// (cross-axis) fallback used to draw and what made the source ambiguous
/// ("面が曖昧" — `docs/STATUS.md`'s own ★未修正 entry this test closes).
/// 2. **No sibling crossing**: no two of those four edges' own segments cross each other —
/// the merge-side counterpart of [`orthogonal_settings_rules_sample_fan_lane_siblings_never_
/// cross`]'s fan-root claim, now for edges converging on a shared target rather than diverging
/// from a shared source.
#[test]
fn orthogonal_settings_rules_sample_merge_target_entries_are_flow_axis_and_never_cross() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let rs = d.node("RS").expect("RS (ラスタライズ) must exist");
let (l, t, r, bo) = rs.bounds();
let merge: Vec<&PlacedEdge> = d.edges.iter().filter(|e| e.to == "RS").collect();
assert_eq!(
merge.len(),
4,
"RS's own four-way merge (mermaid/数式/usvg/ページ描画): {:?}",
merge.iter().map(|e| e.from.as_str()).collect::<Vec<_>>()
);
for e in &merge {
let entry = e.points.last().expect("every edge has at least one point");
let on_left_or_right_face = (entry.x - (l - orthogonal::PORT_INSET)).abs() < 1e-6
|| (entry.x - (r + orthogonal::PORT_INSET)).abs() < 1e-6;
let on_top_or_bottom_face = (entry.y - (t - orthogonal::PORT_INSET)).abs() < 1e-6
|| (entry.y - (bo + orthogonal::PORT_INSET)).abs() < 1e-6;
assert!(
on_left_or_right_face && !on_top_or_bottom_face,
"{}->RS must enter RS's own flow-axis (Left) face, never Top/Bottom: entry={entry:?}, \
RS bounds=({l},{t},{r},{bo})",
e.from
);
assert!(
entry.y > t + 1e-6 && entry.y < bo - 1e-6,
"{}->RS's own entry point must sit strictly inside RS's own vertical span, not flush \
on a corner (§10-1 item 1's own 'ポートは角から8px以上'): entry={entry:?}, RS \
bounds=({l},{t},{r},{bo})",
e.from
);
}
for i in 0..merge.len() {
for j in (i + 1)..merge.len() {
let (a, b) = (merge[i], merge[j]);
for wa in a.points.windows(2) {
for wb in b.points.windows(2) {
assert!(
orthogonal::segment_crossing(wa, wb).is_none(),
"{}->RS crosses {}->RS's own segment ({:?}-{:?} vs {:?}-{:?}) — sibling \
merge stubs into the same target must never cross: {} points={:?}, \
{} points={:?}",
a.from,
b.from,
wa[0],
wa[1],
wb[0],
wb[1],
a.from,
a.points,
b.from,
b.points
);
}
}
}
}
}
/// §10-3 item 12's own real motivating bug (`docs/FEATURE-MERMAID-RENDERER.md`, user report
/// "セルに合わせるの3合流でポートが中心より上へ回り込む"): `FIT`(`セルに合わせる`)'s own three-way
/// merge (`RS`(`ラスタライズ`, aligned — the trunk, offset 0), `IM`(`デコード`) and
/// `VD`(`キーフレーム`), both genuinely below `FIT`'s own centre in this `LR` layout). Before item
/// 12's fix, `evict`'s own array-symmetric re-splice moved the aligned claim from wherever it
/// naturally sorted to the claims array's own geometric middle index, which could drag a
/// same-side sibling across the centre line along the way — on this exact face, `RS` naturally
/// sorts *first* (its own other end, `MM`/`mermaid`, sits almost exactly on `FIT`'s own centre) and
/// `round((3-1)/2) = 1` used to force it to index 1, dragging `IM` down to index 0 and flipping its
/// offset from the `+16` its true side calls for to `-16` — landing it *above* `FIT`'s centre even
/// though `IM` genuinely sits below it, exactly the reported symptom. `3a`'s own reference geometry
/// (`docs/mermaid-theme/handoff/round3-Konoma-Flowchart-Routing.dc.html`) confirms both non-trunk
/// members land below centre (`338`/`354` against a centre of `322`), matching this test's own
/// `+16`/`+32`.
#[test]
fn orthogonal_settings_rules_sample_fit_merge_keeps_same_side_siblings_on_the_same_side() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let fit = d.node("FIT").expect("FIT (セルに合わせる) must exist");
let rs = d
.edges
.iter()
.find(|e| e.from == "RS" && e.to == "FIT")
.expect("RS->FIT (幹) must exist");
let im = d
.edges
.iter()
.find(|e| e.from == "IM" && e.to == "FIT")
.expect("IM->FIT (デコード) must exist");
let vd = d
.edges
.iter()
.find(|e| e.from == "VD" && e.to == "FIT")
.expect("VD->FIT (キーフレーム) must exist");
assert_eq!(
rs.points.len(),
2,
"RS->FIT is the trunk — a straight 2-point line entering exactly on FIT's own centre: {:?}",
rs.points
);
let rs_entry = rs.points.last().unwrap().y;
assert!(
(rs_entry - fit.center.y).abs() < 1e-6,
"RS->FIT (aligned) enters exactly on FIT's centre: {rs_entry} vs {}",
fit.center.y
);
let im_entry = im.points.last().unwrap().y;
let vd_entry = vd.points.last().unwrap().y;
assert!(
(im_entry - (fit.center.y + orthogonal::PORT_SPACING)).abs() < 1e-6,
"IM->FIT (デコード) enters PORT_SPACING BELOW FIT's centre — never above it, the reported \
side-crossing bug: {im_entry} vs {}",
fit.center.y
);
assert!(
(vd_entry - (fit.center.y + 2.0 * orthogonal::PORT_SPACING)).abs() < 1e-6,
"VD->FIT (キーフレーム) enters 2*PORT_SPACING below FIT's centre, on the SAME side as \
IM->FIT (both genuinely below centre): {vd_entry} vs {}",
fit.center.y
);
// FIT's own height grows symmetric to the *larger* side (item 12's own "ノードは大きい側に
// 合わせて中心対称に拡大") — 2 steps (IM, VD) reserved on both sides even though the near side
// carries no claim at all: 2*(2*PORT_SPACING + PORT_CLEARANCE) = 80px, matching `3a`'s own
// 高さ80 reference.
let expected_h = 2.0 * (2.0 * orthogonal::PORT_SPACING + orthogonal::PORT_CLEARANCE);
assert!(
(fit.size.h - expected_h).abs() < 1e-6,
"FIT's own height must be exactly 2*(2*PORT_SPACING+PORT_CLEARANCE) = {expected_h}px: got \
{}",
fit.size.h
);
}
/// §10-3 item 13's own real motivating bug (`docs/FEATURE-MERMAID-RENDERER.md`, user report "線が
/// ページ描画のノードから出ていない・右上の角から生えて見える"): `PD`(`ページ描画`)'s own single
/// out-edge to `RS`(`ラスタライズ`) used to have its exit stub dragged off `PD`'s own assigned Right
/// face slot by `MA`(`数式`)'s box sitting in the same pass-through row — `clear_local_route`'s own
/// blind "every point sharing the flagged coordinate slides together" moved the port along with the
/// rest of the run. Pinned two ways: the port sits exactly on `PD`'s own vertical centre (its one
/// and only claim on that face, so `evict` gives it offset 0), and the route genuinely still clears
/// `MA`'s box (the bug this fix must not silently regress into "port stays put, line now crosses
/// 数式 instead").
#[test]
fn orthogonal_settings_rules_sample_page_render_exit_stays_on_its_own_port() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let pd = d.node("PD").expect("PD (ページ描画) must exist");
let ma = d.node("MA").expect("MA (数式) must exist");
let pd_rs = d
.edges
.iter()
.find(|e| e.from == "PD" && e.to == "RS")
.expect("PD->RS must exist");
let exit = pd_rs.points.first().expect("PD->RS must have points");
let (_, t, r, bo) = pd.bounds();
assert!(
(exit.x - (r + orthogonal::PORT_INSET)).abs() < 1e-6,
"PD->RS must leave PD's own Right face, PORT_INSET outside it, not some other x: \
{exit:?} vs PD bounds {:?}",
pd.bounds()
);
assert!(
(exit.y - (t + bo) / 2.0).abs() < 1e-6,
"PD->RS's own exit port must sit exactly on PD's own vertical centre (PD's only claim on \
this face): {exit:?} vs PD bounds {:?}",
pd.bounds()
);
let second = &pd_rs.points[1];
assert!(
(exit.y - second.y).abs() < 1e-6 && (exit.x - second.x).abs() > 1e-6,
"PD must still leave its own Right face horizontally (perpendicular exit, §10-1 item 1), \
not turn immediately at the port: {:?}",
pd_rs.points
);
for w in pd_rs.points.windows(2) {
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], ma),
"PD->RS must still clear MA (数式) even with its own port pinned: segment {w:?} in \
{:?}, MA bounds {:?}",
pd_rs.points,
ma.bounds()
);
}
}
/// A minimal, hand-built counterpart to [`orthogonal_settings_rules_sample_merge_target_entries_
/// are_flow_axis_and_never_cross`] — three plain, single-out-edge sources at three different flow
/// coordinates merging into one target, deliberately shaped (an obstacle, `X`, sitting on `A`'s own
/// row directly ahead of it, `B`'s the "settings rules" sample's own `usvg`-vs-`数式` collision)
/// so the best-effort `rank_lane_bend` retry (`classify`'s own §10-3 item 10 doc: "全ての候補が
/// 交差してもcross-axisのaltへは決して落ちない") fires on a fixture small enough to read by hand
/// rather than only on the 20-node real-world source above.
#[test]
fn orthogonal_synthetic_blocked_merge_still_enters_the_flow_axis_face() {
let src = "flowchart LR\n A --> T[Target]\n B --> T\n C --> T\n A --> X[Blocker]\n \
Z --> X";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let t = d.node("T").expect("T must exist");
let (l, tt, r, bb) = t.bounds();
let merge: Vec<&PlacedEdge> = d.edges.iter().filter(|e| e.to == "T").collect();
assert_eq!(
merge.len(),
3,
"{:?}",
merge.iter().map(|e| e.from.as_str()).collect::<Vec<_>>()
);
for e in &merge {
let entry = e.points.last().unwrap();
let on_flow_axis_face = (entry.x - (l - orthogonal::PORT_INSET)).abs() < 1e-6
|| (entry.x - (r + orthogonal::PORT_INSET)).abs() < 1e-6;
assert!(
on_flow_axis_face,
"{}->T must enter T's own flow-axis face even when its own row is blocked: \
entry={entry:?}, T bounds=({l},{tt},{r},{bb})",
e.from
);
}
}
/// §10-3 item 13's own two user-reported regressions (`docs/FEATURE-MERMAID-RENDERER.md`, this
/// module's own `reserve_pass_through_rows`/`nest_merge_target_hops` fix): `MA`(`数式`) used to sit
/// almost exactly on `PD`(`ページ描画`)'s own row, one column upstream of `RS`(`ラスタライズ`) —
/// directly inside `PD -> RS`'s own pass-through row — forcing `PD -> RS` into a four-bend detour
/// around it. `reserve_pass_through_rows` moves `MA` clear of that row instead of leaving the edge
/// to detour; pinned two ways, the *why* (the row itself is now clear) and the *what* (the route is
/// a plain two-bend hop again, not a detour).
#[test]
fn orthogonal_settings_rules_sample_math_node_is_not_on_page_renders_row() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let pd = d.node("PD").expect("PD (ページ描画) must exist");
let ma = d.node("MA").expect("MA (数式) must exist");
let (_, ma_top, _, ma_bottom) = ma.bounds();
let pd_row = pd.center.y;
assert!(
pd_row < ma_top - 1e-6 || pd_row > ma_bottom + 1e-6,
"MA (数式) must not occupy ページ描画's own pass-through row (its horizontal exit leg runs \
straight through this row on its way to RS): pd_row={pd_row}, MA bounds=({ma_top}, \
{ma_bottom})"
);
}
#[test]
fn orthogonal_settings_rules_sample_page_render_to_rasterise_is_two_bends_not_a_detour() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let pd_rs = d
.edges
.iter()
.find(|e| e.from == "PD" && e.to == "RS")
.expect("PD->RS must exist");
assert_eq!(
pd_rs.points.len(),
4,
"PD->RS must be a plain two-bend hop route once 数式 is out of ページ描画's own \
pass-through row — a longer point list means it is still detouring around something: {:?}",
pd_rs.points
);
}
/// A minimal `SpecEdge`, following `label_boosts_actually_widen_the_flow_axis_segment_dagre_lays_
/// out`'s own hand-built-`SpecEdge` convention — every field this module's own routing code never
/// reads (label, tips, stroke, start/end labels, style) set to its plainest value, since only `from`/
/// `to`/`minlen` matter to `reserve_pass_through_rows`.
fn plain_edge(id: &str, from: &str, to: &str, minlen: usize) -> super::SpecEdge {
super::SpecEdge {
id: id.to_string(),
from: from.to_string(),
to: to.to_string(),
label: None,
tip_start: Tip::None,
tip_end: Tip::Arrow,
stroke: Stroke::Normal,
minlen,
start_label: None,
end_label: None,
style: None,
curve: Curve::Basis,
}
}
/// §10-3 item 13's own rule (`docs/FEATURE-MERMAID-RENDERER.md`), pinned directly against
/// `super::reserve_pass_through_rows` rather than through a full flowchart source: a hand-built
/// four-node layout, `A`(rank 0) skipping straight to `B`(rank 2) — a rank-skipping `A -> B`
/// (`minlen` 2) — with two nodes hand-placed on `A`'s own exact row at the intermediate rank 1:
/// `C` (`A`'s own real child, `A -> C`, must be left exactly where it is) and `W` (no edge to or
/// from `A` at all, only its own unrelated `W -> D`, standing in for the coincidental-occupant case
/// this rule exists to fix). Going through the full flowchart pipeline (`laid_out_flow`) cannot
/// reliably reproduce this exact collision — dagre's own cross-axis packing spreads unrelated
/// same-rank nodes apart by construction, so no small hand-written source was found that actually
/// forces two unrelated nodes onto the identical row — hence the direct call, with full control over
/// the "before" geometry this function's own contract is stated against.
#[test]
fn reserve_pass_through_rows_evicts_an_unrelated_node_but_not_a_real_neighbour() {
let direction = crate::preview::mermaid::flowchart::Direction::LeftToRight;
let mut nodes = vec![
placed_node("A", 0.0, 100.0, 40.0, 20.0),
placed_node("C", 100.0, 100.0, 40.0, 20.0), // A's real child — on A's row on purpose.
placed_node("W", 100.0, 100.0, 40.0, 20.0), // unrelated — also on A's row on purpose.
placed_node("B", 200.0, 100.0, 40.0, 20.0),
];
let node_rank: HashMap<String, i32> = [
("A".to_string(), 0),
("C".to_string(), 1),
("W".to_string(), 1),
("B".to_string(), 2),
]
.into_iter()
.collect();
let edge_ac = plain_edge("e_ac", "A", "C", 1);
let edge_ab = plain_edge("e_ab", "A", "B", 2);
let edge_wd = plain_edge("e_wd", "W", "D", 1);
let drawable = vec![
super::Drawable {
edge: &edge_ac,
tail: "A".to_string(),
head: "C".to_string(),
},
super::Drawable {
edge: &edge_ab,
tail: "A".to_string(),
head: "B".to_string(),
},
super::Drawable {
edge: &edge_wd,
tail: "W".to_string(),
head: "D".to_string(),
},
];
// `A -> B`'s own shape is the only thing this test needs eligible: a plain, non-branching,
// adjacent-source-facing merge into a lone target — exactly what `route_flowchart`'s own trial
// route would classify as `is_pass_through_shape` for this hand-built fixture.
let eligible: HashSet<String> = ["e_ab".to_string()].into_iter().collect();
let moved =
super::reserve_pass_through_rows(direction, &mut nodes, &node_rank, &drawable, &eligible);
assert!(
moved,
"must actually evict W for this test to mean anything"
);
let row = |id: &str| nodes.iter().find(|n| n.id == id).unwrap().center.y;
let a_row = row("A");
assert!(
(row("C") - a_row).abs() < 1e-6,
"C (A's own direct child, A -> C) must stay exactly on A's own row — the guard must not \
evict a real neighbour: a_row={a_row}, c_row={}",
row("C")
);
assert!(
(row("W") - a_row).abs() >= 22.0 - 1e-6,
"W (unrelated to A) must be evicted clear of A's own pass-through row (half its own height \
+ PASS_THROUGH_CLEARANCE = 10+12 = 22px): a_row={a_row}, w_row={}",
row("W")
);
}
/// §10-3 item 10's own trailing "ホップ x の入れ子" (`docs/FEATURE-MERMAID-RENDERER.md`) — the
/// perpendicular-crossing invariant `orthogonal_settings_rules_sample_merge_target_entries_are_
/// flow_axis_and_never_cross` already pins (`orthogonal::segment_crossing`) cannot see two siblings'
/// vertical hop legs simply *coinciding* (`セルに合わせる`'s own `デコード`/`キーフレーム`, this
/// fix's own motivating bug — both landed on the exact same independently-computed hop `x` before
/// `nest_merge_target_hops`), nor a sibling whose route never went through `EdgeShape::rank_lane_
/// bend` at all (`ラスタライズ`'s own `mermaid -> RS` and `数式 -> RS`, both ordinary adjacent-rank
/// merges — `数式 -> RS`'s hop crossed `ページ描画 -> RS`'s own horizontal source-leg once `数式`
/// moved out of `ページ描画`'s row, the second real bug this fix closes).
/// `orthogonal::polylines_cross` (the exact predicate `nest_merge_target_hops` itself uses to decide
/// whether a candidate slot is clear) is the general question; this test asks it of every pair of
/// siblings converging on each of the sample's two multi-way merges.
#[test]
fn orthogonal_settings_rules_sample_merge_siblings_never_cross_or_coincide() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for target in ["RS", "FIT"] {
let merge: Vec<&PlacedEdge> = d.edges.iter().filter(|e| e.to == target).collect();
assert!(
merge.len() >= 2,
"{target} must have at least two incoming edges to be a meaningful test: {:?}",
merge.iter().map(|e| e.from.as_str()).collect::<Vec<_>>()
);
for i in 0..merge.len() {
for j in (i + 1)..merge.len() {
assert!(
!orthogonal::polylines_cross(&merge[i].points, &merge[j].points),
"{}->{target} crosses or coincides with {}->{target} — sibling merge routes \
must never cross or overlap: {} points={:?}, {} points={:?}",
merge[i].from,
merge[j].from,
merge[i].from,
merge[i].points,
merge[j].from,
merge[j].points
);
}
}
}
}
/// §10-3 item 10's own "8px 刻み" (`docs/FEATURE-MERMAID-RENDERER.md`), restated precisely rather
/// than as a blanket "every pair of siblings differs by 8px regardless of geometry": two sibling
/// merge edges whose vertical hop legs would otherwise sit at overlapping rows (`IM`(`デコード`)
/// and `VD`(`キーフレーム`), both genuinely below `FIT`(`セルに合わせる`)'s own centre, `orthogonal_
/// settings_rules_sample_fit_merge_keeps_same_side_siblings_on_the_same_side`'s own doc has the
/// full row picture) must land at least [`orthogonal::PORT_CLEARANCE`] apart — never on the
/// identical `x` [`nest_merge_target_hops`]'s own doc reports as this fix's original motivating bug.
#[test]
fn orthogonal_settings_rules_sample_fit_merge_hops_are_spaced_at_least_port_clearance_apart() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let im = d
.edges
.iter()
.find(|e| e.from == "IM" && e.to == "FIT")
.expect("IM->FIT must exist");
let vd = d
.edges
.iter()
.find(|e| e.from == "VD" && e.to == "FIT")
.expect("VD->FIT must exist");
assert_eq!(
im.points.len(),
4,
"IM->FIT must be a two-bend hop route: {:?}",
im.points
);
assert_eq!(
vd.points.len(),
4,
"VD->FIT must be a two-bend hop route: {:?}",
vd.points
);
let im_hop = im.points[1].x;
let vd_hop = vd.points[1].x;
assert!(
(im_hop - vd_hop).abs() >= orthogonal::PORT_CLEARANCE - 1e-6,
"IM->FIT and VD->FIT's own rows overlap (both genuinely sit below FIT's centre) — their \
hops must be nested at least PORT_CLEARANCE apart, never land on the same x: \
im_hop={im_hop} vd_hop={vd_hop}"
);
}
/// [`orthogonal::nest_merge_target_hops`]'s own two invariants, generalised past the one 20-node
/// sample above to the whole [`CORPUS`] (every direction, subgraphs included) plus
/// [`SETTINGS_RULES_SAMPLE`] — `nest_merge_target_hops` itself carries no `tree.is_empty()`/
/// direction guard (unlike `reserve_pass_through_rows`, checked separately below), so nothing
/// about this invariant is scoped to a subset of diagrams: no two *genuine merge siblings*
/// converging on the same target may ever cross or coincide, full stop.
///
/// Scoped to `orthogonal::classify`'s own definition of a merge sibling — `source_out_degree <= 1`
/// (`is_merge_hop_candidate`'s own guard, `orthogonal.rs`) — not to every edge that happens to share
/// a target: `subgraph-bypass`'s own `X -> Y` shares a target with `B -> Y`, but `X` itself branches
/// (`X --> Y`, `X --> A`), so `classify` draws `X -> Y` as a *branch* shape, an unrelated shape
/// family this fix never touches — its own route can cross a foreign sibling for reasons that
/// predate and are out of scope for this fix (a pre-existing, structurally different bug class:
/// a branching source's own `staircase` fallback detour, not a merge target's own port nesting).
#[test]
fn orthogonal_merge_sibling_hops_never_cross_or_coincide_across_corpus() {
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain([("settings-rules-sample", SETTINGS_RULES_SAMPLE)])
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mut out_degree: HashMap<&str, usize> = HashMap::new();
for e in &d.edges {
*out_degree.entry(e.from.as_str()).or_insert(0) += 1;
}
let mut by_target: HashMap<&str, Vec<&PlacedEdge>> = HashMap::new();
for e in &d.edges {
// `Stroke::Invisible` (`~~~`) is a layout-only link mermaid itself never draws a line
// for (`svg.rs`'s own `Stroke::Invisible => return`) — a "crossing" against one is not
// a visible defect, so it is out of scope for this invariant the same way it is out of
// scope for the renderer itself.
if e.stroke == Stroke::Invisible {
continue;
}
// A genuine merge sibling only, matching `is_merge_hop_candidate`'s own scope — a
// branching source's own edge into this same target is a different shape family
// (this test's own doc explains why `subgraph-bypass` needs this filter).
if out_degree.get(e.from.as_str()).copied().unwrap_or(0) > 1 {
continue;
}
by_target.entry(e.to.as_str()).or_default().push(e);
}
for (target, merge) in by_target {
if merge.len() < 2 {
continue;
}
for i in 0..merge.len() {
for j in (i + 1)..merge.len() {
assert!(
!orthogonal::polylines_cross(&merge[i].points, &merge[j].points),
"{name}: {}->{target} crosses or coincides with {}->{target}: {} \
points={:?}, {} points={:?}",
merge[i].from,
merge[j].from,
merge[i].from,
merge[i].points,
merge[j].from,
merge[j].points
);
}
}
}
}
}
/// The mirror of [`orthogonal_merge_sibling_hops_never_cross_or_coincide_across_corpus`] on the
/// **source** side: two edges leaving the same node never cross each other.
///
/// That is what §10-1 item 1's rule 1 is *for* — "もう一方の端点のcross座標順" orders a face's
/// ports so the lines going to those other ends stay in the same order they leave in — and it is
/// stated here because the rule was read along the wrong axis until §10-5 round 5
/// (`orthogonal::FaceClaim::other_tangent`'s own doc): on a **cross-axis** face, "the other end's
/// cross coordinate" is perpendicular to the axis the ports are actually laid out along, so the
/// order it produced said nothing about where the two lines were going. `zz-design-2c`'s own
/// `ジョブ実行系` is where it surfaced once round 5 put `保存層` beside the spine — its two green
/// edges left the same face in the reverse of the order they needed and crossed each other
/// immediately.
///
/// `Stroke::Invisible` is skipped for the same reason the merge-side test skips it: `~~~` is a
/// layout-only link that is never drawn, so it cannot cross anything visibly. So is a **detour** —
/// an edge whose route leaves the box its own two endpoints span, which is the perimeter lane and
/// the `staircase` collision fallback. Those are a different shape family, out of a port-ordering
/// rule's reach by construction (a route that goes right round the outside can cross anything on
/// its way), and exactly the exclusion the merge-side test above states in prose for
/// `subgraph-bypass`'s own `X -> Y` — stated here geometrically so it names the shape rather than
/// the fixture. Every edge whose route stays between its own two ends is in scope, which is what
/// rule 1 actually governs.
#[test]
fn orthogonal_edges_leaving_one_node_never_cross_each_other_across_corpus() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain([("settings-rules-sample", SETTINGS_RULES_SAMPLE)])
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let stays_between = |e: &PlacedEdge| -> bool {
let ends: Vec<(f64, f64, f64, f64)> = d
.nodes
.iter()
.filter(|n| n.id == e.from || n.id == e.to)
.map(|n| n.bounds())
.collect();
let (mut l, mut t, mut r, mut b) = (f64::MAX, f64::MAX, f64::MIN, f64::MIN);
for (nl, nt, nr, nb) in ends {
l = l.min(nl);
t = t.min(nt);
r = r.max(nr);
b = b.max(nb);
}
e.points
.iter()
.all(|p| p.x >= l - 0.01 && p.x <= r + 0.01 && p.y >= t - 0.01 && p.y <= b + 0.01)
};
let mut by_source: HashMap<&str, Vec<&PlacedEdge>> = HashMap::new();
for e in &d.edges {
if e.stroke == Stroke::Invisible || e.from == e.to || !stays_between(e) {
continue;
}
by_source.entry(e.from.as_str()).or_default().push(e);
}
for (source, fan) in by_source {
for i in 0..fan.len() {
for j in (i + 1)..fan.len() {
let hit = fan[i].points.windows(2).find_map(|a| {
fan[j]
.points
.windows(2)
.find_map(|b| orthogonal::segment_crossing(a, b))
});
assert!(
hit.is_none(),
"{name}: {source}->{} crosses {source}->{} at {hit:?}: {:?} vs {:?}",
fan[i].to,
fan[j].to,
fan[i].points,
fan[j].points
);
}
}
}
}
}
/// §10-3 item 13's own rule ("列 A の行 R から出て列 T（T > A+1）へ入る辺は、間の各列で行 R を占め
/// る"), stated purely from the finished layout's own geometry (never `reserve_pass_through_rows`'s
/// own internal rank machinery, so this cannot silently drift the way a second copy of the same
/// rank arithmetic could): for every forward edge whose source and target sit at least a whole
/// node-width apart on the flow axis with a real gap between them, no *unrelated* third node (no
/// edge to the source, in either direction) may sit strictly between them on the flow axis *and*
/// within [`super::PASS_THROUGH_CLEARANCE`] of the source's own cross-axis row.
///
/// Scoped to the same window [`reserve_pass_through_rows`] itself is (`tree.is_empty()`,
/// `mod.rs`'s own call site) — a subgraph diagram is out of scope for that pass, the same known
/// limit `pull_back_fan_ranks` already has (`docs/STATUS.md`'s own ★未修正 entry), so a `CORPUS`
/// name containing "subgraph" is excluded here rather than asserting a rule the production code
/// does not even attempt to keep for it. Also scoped to a non-branching source
/// (`source_out_degree <= 1`, `orthogonal::is_pass_through_shape`'s own doc): a branching source's
/// edge never draws rule 10/13's flow-axis "exit then hop" leg at all — it is a branch (cross-axis
/// exit) or a `fan_lane` member (a *different* corridor concept, §10-3 item 2's own nested lanes —
/// `strokes`'s own `A -> F`, `A` also branching via `A --- B`, is exactly this: real topology skips
/// a column `C` sits in, but the edge's own shape never threads a row through it, so reserving one
/// would repeat the `long-edge` regression this fix exists to close).
#[test]
fn orthogonal_pass_through_row_never_holds_an_unrelated_node_across_corpus() {
use crate::preview::mermaid::flowchart::Direction;
for (name, src) in orthogonal_corpus()
.into_iter()
.filter(|(name, _)| !name.contains("subgraph"))
.chain([("settings-rules-sample", SETTINGS_RULES_SAMPLE)])
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let direction = direction_of(src);
let flow = |p: &Point| match direction {
Direction::LeftToRight | Direction::RightToLeft => p.x,
Direction::TopToBottom | Direction::BottomToTop => p.y,
};
let cross = |p: &Point| match direction {
Direction::LeftToRight | Direction::RightToLeft => p.y,
Direction::TopToBottom | Direction::BottomToTop => p.x,
};
let flow_extent = |n: &PlacedNode| match direction {
Direction::LeftToRight | Direction::RightToLeft => n.size.w / 2.0,
Direction::TopToBottom | Direction::BottomToTop => n.size.h / 2.0,
};
let cross_extent = |n: &PlacedNode| match direction {
Direction::LeftToRight | Direction::RightToLeft => n.size.h / 2.0,
Direction::TopToBottom | Direction::BottomToTop => n.size.w / 2.0,
};
let connected: HashSet<(String, String)> = d
.edges
.iter()
.flat_map(|e| {
[
(e.from.clone(), e.to.clone()),
(e.to.clone(), e.from.clone()),
]
})
.collect();
let mut out_degree: HashMap<&str, usize> = HashMap::new();
for e in &d.edges {
*out_degree.entry(e.from.as_str()).or_insert(0) += 1;
}
for e in &d.edges {
if e.from == e.to {
continue; // self-loop
}
if out_degree.get(e.from.as_str()).copied().unwrap_or(0) > 1 {
continue; // a branching source never draws this shape family — see this test's doc.
}
let (Some(source), Some(target)) = (d.node(&e.from), d.node(&e.to)) else {
continue;
};
let (sf, tf) = (flow(&source.center), flow(&target.center));
// Only a genuine forward, rank-skipping span has a pass-through row to reserve at
// all — a same-column (`aligned`) or immediately-adjacent-rank edge has no
// intermediate column to check.
if tf <= sf + 2.0 * flow_extent(source) {
continue;
}
let row = cross(&source.center);
for n in &d.nodes {
if n.id == e.from || n.id == e.to {
continue;
}
if connected.contains(&(e.from.clone(), n.id.clone())) {
continue; // a real neighbour of the edge's own source — left alone on purpose.
}
let nf = flow(&n.center);
let n_flow_half = flow_extent(n);
// Strictly inside the source-target span, with a whole node-width of margin on
// each side, so a node sharing the source's or target's own rank column (an
// ordinary sibling, not an intermediate-column occupant) is never flagged.
if nf - n_flow_half <= sf + flow_extent(source)
|| nf + n_flow_half >= tf - flow_extent(target)
{
continue;
}
let n_cross_half = cross_extent(n);
assert!(
(cross(&n.center) - row).abs()
>= n_cross_half + super::PASS_THROUGH_CLEARANCE - 1e-6,
"{name}: {}->{} skips an intermediate column that {} (unrelated to {}) still \
occupies on {}'s own pass-through row: source_row={row}, {}'s own \
center={:?}",
e.from,
e.to,
n.id,
e.from,
e.from,
n.id,
n.center
);
}
}
}
}
// ---------------------------------------------------------------------------------------------
// Stage 4: label placement, minimum segment length, port-vs-plate avoidance
// ---------------------------------------------------------------------------------------------
//
// `docs/FEATURE-MERMAID-RENDERER.md` §10-1 item 3. Every labelled corpus source's plate is checked
// against every axis-parallel invariant stage 1-3 already state over the same corpus
// (`orthogonal_corpus`), plus the three new ones this stage adds.
//
// Two of the three sub-rules turned out hard to coax out of a *real* `dagre` layout on purpose,
// dumped and read by hand while this was written (the same way
// `orthogonal_settings_rules_sample_no_longer_pierces_a_sibling_node` was), so each is instead
// covered by a direct, hand-built fixture rather than a diagram source:
//
// * A genuine two-flow-leg split (uneven eviction giving an aligned edge's two ends different
// coordinates, `bridge`'s own doc) — every scratch diagram tried either kept one leg the full
// rank-gap length or the two nodes drifted out of `classify`'s 0.5px aligned window first. Its
// own selection behaviour is covered directly in `orthogonal.rs`'s test module instead
// (`label_slot_picks_the_longer_of_two_flow_axis_segments`), by constructing the split polyline
// by hand.
// * A port stub actually crossing a *foreign* plate (item 3's second rule). `dagre`'s own
// edge-label reservation (the same mechanism `label_boosts_actually_widen_...` below proves)
// turns out to keep every other same-rank node clear of a label's own footprint by construction
// — pushing the label wider pushes its rank-mates out by roughly the same amount, several
// diagrams and node-size combinations tried, so no corpus source or hand-built `GraphSpec` here
// reaches a genuine crossing to have avoided. `orthogonal::avoid_label_plates` is instead proven
// directly (`avoid_label_plates_pushes_only_the_port_that_actually_crosses_a_plate` below,
// `avoid_label_plates_ignores_a_reverse_edge` in `orthogonal.rs`), and
// `no_label_plate_is_crossed_by_a_foreign_edges_segment` stands as the regression guard for the
// day some future routing change does reach one.
/// Every labelled edge's plate, across [`orthogonal_corpus`].
fn labelled_plates(d: &Diagram) -> Vec<(&PlacedEdge, &super::PlacedEdgeLabel)> {
d.edges
.iter()
.filter_map(|e| e.label.as_ref().map(|l| (e, l)))
.collect()
}
/// Every routed polyline in `d`, keyed by the edge's own index — [`orthogonal::plate_coverage`]
/// wants a map by edge id, and a finished [`Diagram`] no longer carries the ids
/// [`lay_out_spec_pass`] used, so the index stands in for one. All that matters is that the plate's
/// own edge can be told apart from every other, which an index does exactly as well.
///
/// [`lay_out_spec_pass`]: super::lay_out_spec_pass
fn routes_by_index(d: &Diagram) -> HashMap<String, Vec<Point>> {
d.edges
.iter()
.enumerate()
.map(|(i, e)| (i.to_string(), e.points.clone()))
.collect()
}
/// The slot production actually chose for edge `i`'s own plate — [`orthogonal::label_slot_clear`]
/// with the very same coverage question `lay_out_spec_pass` asked
/// ([`orthogonal::plate_coverage`]), never the coverage-free [`orthogonal::label_slot`].
///
/// This distinction is the whole reason the helper exists: since §10-5 round 5 the two can name
/// **different segments**, and a test that re-derived the slot from the coverage-free function
/// would be measuring a segment the drawing does not use — konoma's own "the instrument drifted
/// off the production path" failure mode (`docs/FEATURE-MERMAID-RENDERER.md` §6), caught here
/// while writing the rule rather than after shipping it.
fn plate_slot(
d: &Diagram,
direction: crate::preview::mermaid::flowchart::Direction,
i: usize,
) -> Option<orthogonal::LabelSlot> {
let routes = routes_by_index(d);
let e = d.edges.get(i)?;
let size = e.label.as_ref()?.size;
let own = i.to_string();
orthogonal::label_slot_clear(direction, &e.points, &|center| {
orthogonal::plate_coverage(center, size, &own, &routes, &d.nodes, &d.clusters)
})
}
/// Every axis-parallel segment of `e`'s own polyline, as `(a, b)` pairs — what a plate is allowed
/// to sit on top of without that counting as "off the line".
fn own_segments(e: &PlacedEdge) -> impl Iterator<Item = (&Point, &Point)> {
e.points.windows(2).map(|w| (&w[0], &w[1]))
}
/// Item 3's first rule, restated as a corpus invariant: every labelled edge's plate is centred
/// **on** one of its own edge's segments (within a fraction of a px — the two are built from the
/// same arithmetic, so this is really asking "did the wiring stay connected", not "is the geometry
/// approximately right").
#[test]
fn every_label_plate_centre_sits_on_its_own_edges_line() {
for (name, src) in orthogonal_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for (e, l) in labelled_plates(&d) {
let on_a_segment = own_segments(e).any(|(a, b)| {
let on_seg = |p: &Point| {
let within_x = p.x >= a.x.min(b.x) - AXIS_EPS && p.x <= a.x.max(b.x) + AXIS_EPS;
let within_y = p.y >= a.y.min(b.y) - AXIS_EPS && p.y <= a.y.max(b.y) + AXIS_EPS;
let collinear =
((b.x - a.x) * (p.y - a.y) - (b.y - a.y) * (p.x - a.x)).abs() < 1e-3;
within_x && within_y && collinear
};
on_seg(&l.center)
});
assert!(
on_a_segment,
"{name}: label {:?} centre {:?} is not on any segment of {:?}",
l.label.lines, l.center, e.points
);
}
}
}
/// Item 3's minimum-length rule, over every labelled edge whose chosen segment is the flow-axis
/// one — the only kind [`super::apply_label_growth`]'s retry loop can actually widen (a
/// cross-axis-only label, reachable only through a `reverse`/`staircase` edge, is a documented gap
/// — [`orthogonal::LabelSlot::is_flow_axis`]'s own doc). `orthogonal_dag_corpus`, not the full
/// corpus, for the same reason [`orthogonal_bend_count_never_exceeds_two`] uses it: a back edge's
/// label is drawn from dagre's own waypoint chain, which this stage does not reach.
#[test]
fn labelled_flow_axis_segments_meet_their_minimum_length() {
for (name, src) in orthogonal_dag_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for i in 0..d.edges.len() {
let Some(l) = d.edges[i].label.as_ref() else {
continue;
};
let Some(slot) = plate_slot(&d, direction_of(src), i) else {
continue;
};
if !slot.is_flow_axis {
continue;
}
let need = orthogonal::label_min_length(l.size, slot.horizontal);
assert!(
slot.length + 1e-6 >= need,
"{name}: labelled segment {:?} is {}px, short of the {}px minimum for plate {:?}",
d.edges[i].points,
slot.length,
need,
l.size
);
}
}
}
/// §10-5 round 5's own rule as a whole-corpus invariant: **no label plate is laid over another
/// edge's line.** A plate is opaque, so a line under one is simply gone from the picture, and a
/// plate over a *sibling's* entry leg into a busy face is worse than that — it is what made
/// `avoid_label_plates` push that sibling's port out of source order and put a crossing in
/// `zz-design-2c`'s own three-way merge (`orthogonal::label_slot_clear`'s own doc).
///
/// The plate's **own** edge is the one thing it is allowed to cover — that is what "線上プレート"
/// means. Stated over `orthogonal_full_corpus` plus the orthogonal-only fixtures, so it sees the
/// design references and the narrow regression sources alike.
///
/// Deliberately about *lines* only, not about node boxes and frame borders: those are counted by
/// [`orthogonal::plate_coverage`] too and are preferred against when a clear segment exists, but a
/// plate can still legitimately end up on a frame's border when **every** segment of its own edge
/// covers something (`zz-design-2b`'s own `HTTPS`, whose three candidate segments cover
/// `クライアント`'s border, `エディタ拡張`'s leg and `クラウド`'s border respectively — one apiece).
/// Lines are the half that has a consequence beyond the plate itself, and the half the rule is
/// stated on.
#[test]
fn invariant_orthogonal_no_label_plate_covers_a_foreign_line() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for (i, e) in d.edges.iter().enumerate() {
let Some(l) = e.label.as_ref() else { continue };
for (j, other) in d.edges.iter().enumerate() {
if i == j {
continue;
}
let hit = other.points.windows(2).find(|w| {
orthogonal::segment_crosses_plate_box(&w[0], &w[1], &l.center, l.size)
});
assert!(
hit.is_none(),
"{name}: {}->{}'s plate {:?} at {:?} is laid over {}->{}'s own line {:?}",
e.from,
e.to,
l.label.lines,
l.center,
other.from,
other.to,
hit
);
}
}
}
}
/// Parses `src`'s own `direction` line without going through the whole `lay_out_flow` pipeline —
/// [`labelled_flow_axis_segments_meet_their_minimum_length`]'s own use of
/// [`orthogonal::label_slot`] needs it directly, the same value [`Flowchart::direction`] carries.
fn direction_of(src: &str) -> crate::preview::mermaid::flowchart::Direction {
parse(src)
.unwrap_or_else(|e| panic!("corpus source must parse: {e}"))
.direction
}
/// Item 3's growth rule stated the way the task itself asks for it: a long label widens the rank
/// gap it sits in; a short one does not push the diagram wider than an unlabelled version would
/// be. CJK, because that is what the real report (`docs/STATUS.md`'s mermaid work) was about.
/// `LR`, not `TD`: this diagram's flow axis is horizontal there, so a *wide* single-line label —
/// the ordinary shape a long label takes — is what stretches the gap, matching how the rank gap
/// actually grows (`lay_out_spec_pass`'s own doc: `TD`/`BT` tracks a label's raw *height*,
/// `LR`/`RL` its raw *width*) rather than needing an author-written `<br>` to make the label tall.
#[test]
fn a_long_cjk_label_widens_the_rank_gap_and_a_short_one_does_not() {
let bare = laid_out_flow(
"flowchart LR\n A[Start] --> B[End]",
"basis",
"konoma-orthogonal",
);
let short = laid_out_flow(
"flowchart LR\n A[Start] -->|x| B[End]",
"basis",
"konoma-orthogonal",
);
let long = laid_out_flow(
"flowchart LR\n A[Start] -->|とても長いラベルのテキストです、これはとても長い| B[End]",
"basis",
"konoma-orthogonal",
);
let gap = |d: &Diagram| {
let e = &d.edges[0];
(e.points.last().unwrap().x - e.points[0].x).abs()
};
let (bare_gap, short_gap, long_gap) = (gap(&bare), gap(&short), gap(&long));
assert!(
short_gap > bare_gap,
"even a 1-char label must reserve some rank space: {short_gap} vs bare {bare_gap}"
);
assert!(
long_gap > short_gap + 50.0,
"a long multi-em CJK label must widen the gap far more than a 1-char label: \
long={long_gap} short={short_gap}"
);
}
/// A hand-built [`GraphSpec`] with 2 nodes almost touching (`ranksep`-scale gap dwarfed by the
/// label) proves `label_boosts` — [`lay_out_spec_pass`]'s own new parameter — actually reaches
/// dagre: the *same* pass, called once with an empty boost map and once with a large one for the
/// one labelled edge, must come back with a measurably longer flow-axis segment when boosted. This
/// is the wiring stage 4's growth loop depends on ([`apply_label_growth`]'s own doc proves the
/// *loop's* bookkeeping separately); real diagrams rarely ask the loop to do anything at all — see
/// this module's own note on why — so this is what actually exercises the boosted code path rather
/// than leaving it provably-correct-but-never-run.
#[test]
fn label_boosts_actually_widen_the_flow_axis_segment_dagre_lays_out() {
let node = |id: &str| super::SpecNode {
id: id.to_string(),
glyph: Glyph::Flow(Shape::Rect),
label: Label::measure(id),
size: Size::new(30.0, 20.0),
panel: None,
style: None,
has_class: true,
};
let edge = super::SpecEdge {
id: "e1".to_string(),
from: "A".to_string(),
to: "B".to_string(),
label: Some(Label::measure("a fairly long edge label")),
tip_start: Tip::None,
tip_end: Tip::Arrow,
stroke: Stroke::Normal,
minlen: 1,
start_label: None,
end_label: None,
style: None,
curve: Curve::Basis,
};
let spec = super::GraphSpec {
direction: crate::preview::mermaid::flowchart::Direction::TopToBottom,
nodes: vec![node("A"), node("B")],
edges: vec![edge],
blocks: Vec::new(),
routing: orthogonal::Routing::Orthogonal,
fixed_self_loops: false,
};
let flow_gap = |boosts: &HashMap<String, f64>| {
let (diagram, _required, _shortfall) =
super::lay_out_spec_pass(&spec, &HashMap::new(), boosts)
.unwrap_or_else(|e| panic!("hand-built spec must lay out: {e}"));
let e = &diagram.edges[0];
(e.points.last().unwrap().y - e.points[0].y).abs()
};
let unboosted = flow_gap(&HashMap::new());
let mut boosts = HashMap::new();
boosts.insert("e1".to_string(), 300.0);
let boosted = flow_gap(&boosts);
assert!(
boosted > unboosted + 250.0,
"a 300px label_boosts entry must reach dagre and widen the rank gap by roughly that much: \
unboosted={unboosted} boosted={boosted}"
);
}
/// [`apply_label_growth`]'s own contract, stated directly: it **adds** each pass's shortfall onto
/// the running total (not `max`, unlike [`apply_growth`]'s node sizes — that function's own doc
/// explains why the two need different combinators), only for a positive shortfall, and reports
/// whether anything grew.
#[test]
fn apply_label_growth_accumulates_positive_shortfalls_and_ignores_the_rest() {
let mut boosts: HashMap<String, f64> = HashMap::new();
boosts.insert("already".to_string(), 10.0);
let mut shortfall: HashMap<String, f64> = HashMap::new();
shortfall.insert("already".to_string(), 5.0); // must ADD to 15, not replace with 5
shortfall.insert("fresh".to_string(), 20.0); // a brand new entry
shortfall.insert("met".to_string(), 0.0); // not actually short — must not be recorded at all
shortfall.insert("negative".to_string(), -1.0); // defensive: never subtracts
let grew = super::apply_label_growth(&mut boosts, &shortfall);
assert!(grew, "a positive shortfall must report growth");
assert!((boosts["already"] - 15.0).abs() < 1e-9, "{:?}", boosts);
assert!((boosts["fresh"] - 20.0).abs() < 1e-9, "{:?}", boosts);
assert!(
!boosts.contains_key("met"),
"a zero shortfall adds no entry"
);
assert!(
!boosts.contains_key("negative"),
"a negative shortfall must never be applied"
);
// A second call with an all-zero shortfall must report no further growth and leave the totals
// exactly where they were — the loop-stopping condition `lay_out_spec` relies on.
let mut zero: HashMap<String, f64> = HashMap::new();
zero.insert("already".to_string(), 0.0);
let grew_again = super::apply_label_growth(&mut boosts, &zero);
assert!(!grew_again);
assert!((boosts["already"] - 15.0).abs() < 1e-9);
}
/// §10-1 item 3's second rule ("ポートの垂直レーンがラベルプレートと重なる場合はポートをさらに
/// 16px外へ"), over the whole corpus: no plate ever ends up crossed by a *foreign* edge's segment
/// — either it never would have (the common case) or `avoid_label_plates` pushed the port that
/// would have crossed it clear. An edge's own line is exempt (it is what the plate sits on, by
/// item 3's first rule) and so is its own arrow tip.
#[test]
fn no_label_plate_is_crossed_by_a_foreign_edges_segment() {
for (name, src) in orthogonal_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for (owner, l) in labelled_plates(&d) {
let (pl, pt, pr, pb) = (
l.center.x - l.size.w / 2.0,
l.center.y - l.size.h / 2.0,
l.center.x + l.size.w / 2.0,
l.center.y + l.size.h / 2.0,
);
for other in &d.edges {
if std::ptr::eq(other, owner) {
continue;
}
for (a, b) in own_segments(other) {
let crosses = if (a.y - b.y).abs() < AXIS_EPS {
let y = a.y;
let (x0, x1) = (a.x.min(b.x), a.x.max(b.x));
y >= pt && y <= pb && x1 >= pl && x0 <= pr
} else if (a.x - b.x).abs() < AXIS_EPS {
let x = a.x;
let (y0, y1) = (a.y.min(b.y), a.y.max(b.y));
x >= pl && x <= pr && y1 >= pt && y0 <= pb
} else {
false
};
assert!(
!crosses,
"{name}: {:?}->{:?}'s segment {a:?}->{b:?} runs through {:?}->{:?}'s \
label plate {:?}",
other.from, other.to, owner.from, owner.to, l.label.lines
);
}
}
}
}
}
/// [`orthogonal::avoid_label_plates`] itself, directly: a port whose stub runs through a foreign
/// plate must move exactly [`orthogonal::PORT_SPACING`] further from its own node, and an edge that
/// never crosses anything must come back byte-identical.
#[test]
fn avoid_label_plates_pushes_only_the_port_that_actually_crosses_a_plate() {
use crate::preview::mermaid::flowchart::Direction;
use orthogonal::{avoid_label_plates, EligibleEdge};
let a = placed_node("A", 100.0, 0.0, 60.0, 40.0);
let b = placed_node("B", 100.0, 200.0, 60.0, 40.0);
let c = placed_node("C", 300.0, 0.0, 60.0, 40.0);
let d = placed_node("D", 300.0, 200.0, 60.0, 40.0);
let nodes = vec![a, b, c, d];
let edges = vec![
EligibleEdge {
id: "ab",
source: "A",
target: "B",
raw: &[],
source_rank: Some(0),
target_rank: Some(1),
source_out_degree: 1,
target_in_degree: 1,
aside: false,
},
EligibleEdge {
id: "cd",
source: "C",
target: "D",
raw: &[],
source_rank: Some(0),
target_rank: Some(1),
source_out_degree: 1,
target_in_degree: 1,
aside: false,
},
];
let routed = orthogonal::route_flowchart(
Direction::TopToBottom,
&nodes,
&[],
&edges,
&std::collections::HashMap::new(),
false,
);
let mut points = routed.points;
let ab_before = points["ab"].clone();
let cd_before = points["cd"].clone();
// A plate sitting squarely on top of `ab`'s own stub near A's face — not `ab`'s own label
// (different edge id), so it counts as foreign for `ab` and must push it; `cd`'s stub is far
// away (x=300) and must be left untouched.
let mut plates: HashMap<String, super::PlacedEdgeLabel> = HashMap::new();
plates.insert(
"someone-elses-label".to_string(),
super::PlacedEdgeLabel {
center: Point::new(ab_before[0].x, (ab_before[0].y + ab_before[1].y) / 2.0),
size: Size::new(40.0, 14.0),
label: Label::measure("x"),
},
);
avoid_label_plates(
Direction::TopToBottom,
&nodes,
&[],
&edges,
&mut points,
&mut plates,
&std::collections::HashMap::new(),
);
assert_ne!(points["ab"], ab_before, "ab's port must have been pushed");
assert_eq!(
(points["ab"][0].x - ab_before[0].x).abs(),
orthogonal::PORT_SPACING,
"the push must be exactly PORT_SPACING: {:?} vs {:?}",
points["ab"][0],
ab_before[0]
);
assert_eq!(
points["cd"], cd_before,
"cd shares no plate with anything and must be left exactly as routed"
);
}
// ---------------------------------------------------------------------------------------------
// Stage 5: the perimeter lane (§10-1 item 4)
// ---------------------------------------------------------------------------------------------
/// The smallest box holding every node and every subgraph frame in `d` — the same thing
/// `orthogonal::content_bounds` computes (private to that module, so this is its own independent
/// arithmetic over the public `Diagram` fields, not a call into the implementation it is checking).
fn diagram_content_bounds(d: &Diagram) -> (f64, f64, f64, f64) {
let mut l = f64::INFINITY;
let mut t = f64::INFINITY;
let mut r = f64::NEG_INFINITY;
let mut b = f64::NEG_INFINITY;
for n in &d.nodes {
let (nl, nt, nr, nb) = n.bounds();
l = l.min(nl);
t = t.min(nt);
r = r.max(nr);
b = b.max(nb);
}
for c in &d.clusters {
let (cl, ct, cr, cb) = c.bounds();
l = l.min(cl);
t = t.min(ct);
r = r.max(cr);
b = b.max(cb);
}
(l, t, r, b)
}
/// Every `(name, from, to)` corpus edge that excurses past the content box **without** being a
/// genuine back edge — a collision-fallback forward edge (`EdgeShape::staircase`) whose own local
/// route (`route_with_ports`'s own doc — reverted off the perimeter lane 2026-09-01) can stray
/// outside the content box by whatever amount dagre's own waypoint chain and
/// `orthogonal::clear_local_route` produce, with no `PERIMETER_MARGIN + k*PERIMETER_LANE_SPACING`
/// guarantee at all — that guarantee is item 4's own, and it is written about the perimeter lane
/// specifically, which only a true `reverse` (non-self-loop) edge draws from now.
///
/// `classify` (the function that actually decides `reverse` vs `staircase`) is private to
/// `orthogonal.rs`, and a finished [`Diagram`] carries no shape tag a test could read back — so
/// this list is reasoned from each source's own topology instead (verified against `classify`'s
/// own rule, "target rank ≤ source rank" for a genuine back edge, applied to each source's own
/// declared chain — the whole corpus was dumped for its own excursion amounts first, over
/// `scratch_dump_perimeter_excursions`, to confirm no entry outside this list needs it):
/// `strokes`' `A<-->F`/`C~~~E` (both forward, `A`/`C` before `F`/`E` in the declared `A---B-.->C
/// ==>D--o E--x F` chain), `long-edge`'s `A->E` (forward — the *other* two excursions on this same
/// source, `E->B` and `C->A`, both close a cycle backward and stay genuine back edges), and
/// `subgraph-bypass`'s `X->Y` (forward — spans the same ranks the `one` frame does without closing
/// any cycle, `orthogonal_dag_corpus`'s own doc on this exact source).
///
/// `subgraph-direction`'s `one->D` joined this list once `shape_crosses_a_node`'s own-endpoint
/// check was added (`route_with_ports`'s own doc on the settings-rules regression). Its own
/// two-step cascade, dumped and read by hand rather than guessed at: the *original* shape (`one`
/// leaves `Top`, `D` receives `Right`) genuinely re-entered `D`'s own real box on its final leg —
/// the same bug class that check exists to catch — so `classify` swapped to the alternate
/// (`one` leaves `Left`, `D` receives `Bottom`); that alternate does *not* touch `D` at all, but
/// its own straight run at `one`'s port height happens to run directly through the row `one`'s own
/// members (`A`/`B`, real, foreign nodes to this edge) sit on — a perfectly ordinary *foreign*-node
/// collision, the ordinary padded test already caught before this fix existed, just never reached
/// for this edge until the first swap started happening for real. Both attempts failing sends it to
/// the raw-derived staircase, whose own port then leaves through `one`'s own outermost (`Left`)
/// face — a small, genuine `PORT_INSET`-scale excursion past the content box, not a perimeter-lane
/// one, the same "still a local route, no margin guarantee" category every other entry here is in.
fn known_staircase_forward_edge(name: &str, from: &str, to: &str) -> bool {
matches!(
(name, from, to),
("strokes", "A", "F")
| ("strokes", "C", "E")
| ("long-edge", "A", "E")
| ("subgraph-bypass", "X", "Y")
| ("subgraph-direction", "one", "D")
)
}
/// How far outside `bounds` a point sits — 0 for a point inside or on the edge, otherwise its
/// distance past whichever side it cleared. What [`orthogonal_perimeter_edges_clear_the_margin`]
/// measures a perimeter edge's route by.
fn excursion(bounds: (f64, f64, f64, f64), p: &Point) -> f64 {
let (l, t, r, b) = bounds;
let dx = (l - p.x).max(p.x - r).max(0.0);
let dy = (t - p.y).max(p.y - b).max(0.0);
dx.max(dy)
}
/// §10-1 item 4's own headline invariant: any edge whose route strays outside the content box at
/// all — a `branch`/`merge`/`aligned` shape never does, since its whole route stays within
/// coordinates existing nodes already occupy, so straying at all is itself the signal this is a
/// perimeter-routed edge — clears it by at least [`orthogonal::PERIMETER_MARGIN`].
///
/// **Test-sufficiency audit finding 4 (2026-09-01)**: run only over `orthogonal_corpus()` (every
/// `CORPUS` source), this invariant never actually exercises `content_bounds`'s own "a cluster's
/// bounds are folded in, not just its members' node boxes" contract — every `CORPUS` subgraph is
/// small enough that its frame never juts out past its members' own node boxes by more than the
/// ordinary member padding, so the check would pass identically even if `content_bounds` read
/// `nodes` alone. `orthogonal_only_corpus()`'s `orthogonal-frame-hugs-backedge` (a long title
/// forcing the frame wider than its one small member) is what actually makes the two readings
/// disagree — see [`orthogonal_frame_hugs_backedge_perimeter_lane_reads_the_frame_not_just_the_nodes`]
/// for the same fact pinned to real numbers, and this crate's own mutation check (temporarily
/// dropping `content_bounds`'s `clusters` loop) confirms this loop is what actually catches it.
#[test]
fn orthogonal_perimeter_edges_clear_the_margin() {
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let bounds = diagram_content_bounds(&d);
for e in &d.edges {
if e.from == e.to {
continue; // a self-loop's small local bump is not a perimeter lane at all.
}
if known_staircase_forward_edge(name, &e.from, &e.to) {
continue; // a local route, not a perimeter one — see that function's own doc.
}
let max_excursion = e
.points
.iter()
.map(|p| excursion(bounds, p))
.fold(0.0_f64, f64::max);
if max_excursion < AXIS_EPS {
continue; // not a perimeter edge — never left the content box at all.
}
assert!(
max_excursion + AXIS_EPS >= orthogonal::PERIMETER_MARGIN,
"{name}: edge {}->{} strays only {max_excursion}px outside the content box, \
short of the {}px margin: {:?}",
e.from,
e.to,
orthogonal::PERIMETER_MARGIN,
e.points
);
}
}
}
/// Finding 4's own specific pin, dumped by hand: `orthogonal-frame-hugs-backedge`'s `one` frame
/// (widened by its own long title, `subgraph-long-title`'s same trick) sits *above* `D`, `X` and
/// `Y`'s own node boxes — `one`'s top edge (y=24) is the true minimum of the whole diagram, well
/// above every node's own top (y=49) — so `Y->X`'s ring lane can only land at `content.top -
/// PERIMETER_MARGIN` if `content_bounds` actually read `one`'s own bounds; a node-only reading
/// would put the ring 25px further down (`49 - 16 = 33`, inside `one`'s own frame by 9px — a
/// direct violation of "at least 16px outside the outermost frame").
#[test]
fn orthogonal_frame_hugs_backedge_perimeter_lane_reads_the_frame_not_just_the_nodes() {
if !text_metrics::fonts_available() {
return;
}
let src = orthogonal_only_corpus()
.into_iter()
.find(|(name, _)| *name == "orthogonal-frame-hugs-backedge")
.unwrap()
.1;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let frame = d.cluster("one").expect("cluster one must exist").bounds();
let bounds = diagram_content_bounds(&d);
// `one`'s frame really is the widest thing here — the fixture's whole point.
assert!(
(bounds.1 - frame.1).abs() < 0.01,
"the fixture must make the frame's own top the diagram's minimum y: content.top={} \
frame.top={}",
bounds.1,
frame.1
);
let yx = d
.edges
.iter()
.find(|e| e.from == "Y" && e.to == "X")
.expect("Y->X must exist");
let topmost = yx.points.iter().map(|p| p.y).fold(f64::INFINITY, f64::min);
assert!(
(bounds.1 - topmost - orthogonal::PERIMETER_MARGIN).abs() < 1.0,
"Y->X's ring lane must sit exactly PERIMETER_MARGIN above content's own top (which \
already folds the frame in): topmost={topmost} content.top={} margin={}",
bounds.1,
orthogonal::PERIMETER_MARGIN
);
// And, directly against the frame itself rather than the whole content box: the ring's own
// topmost excursion (the point this test just pinned) clears `one`'s own top edge by the
// margin too — not just checked indirectly through the diagram's own bounding box, which
// happens to be dominated by the very frame under test here.
let out = frame.1 - topmost;
assert!(
out + AXIS_EPS >= orthogonal::PERIMETER_MARGIN,
"Y->X's topmost point clears frame `one`'s own top edge by only {out}px, short of the \
{}px margin",
orthogonal::PERIMETER_MARGIN
);
}
/// §10-1 item 4's 8px stagger: every perimeter edge's own maximum excursion past the content box
/// is exactly `PERIMETER_MARGIN + k * PERIMETER_LANE_SPACING` for some non-negative integer `k`
/// (its own lane index) — and, over a diagram with more than one perimeter edge, two *different*
/// edges never land on the same `k` (dumped and checked on `long-edge`'s two back edges before
/// this was written: 16px and 24px, `k = 0` and `k = 1`, never both 16px).
#[test]
fn orthogonal_perimeter_edges_stagger_8px_apart() {
for (name, src) in orthogonal_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let bounds = diagram_content_bounds(&d);
let mut lanes: Vec<i64> = Vec::new();
for e in &d.edges {
if e.from == e.to {
continue; // a self-loop's small local bump is not a perimeter lane at all.
}
if known_staircase_forward_edge(name, &e.from, &e.to) {
continue; // a local route, not a perimeter one — see that function's own doc.
}
let max_excursion = e
.points
.iter()
.map(|p| excursion(bounds, p))
.fold(0.0_f64, f64::max);
if max_excursion < AXIS_EPS {
continue;
}
let steps =
(max_excursion - orthogonal::PERIMETER_MARGIN) / orthogonal::PERIMETER_LANE_SPACING;
assert!(
(steps - steps.round()).abs() < 1e-6,
"{name}: edge {}->{} excursion {max_excursion}px is not \
PERIMETER_MARGIN + k*PERIMETER_LANE_SPACING for an integer k (k={steps}): {:?}",
e.from,
e.to,
e.points
);
let lane = steps.round() as i64;
assert!(
!lanes.contains(&lane),
"{name}: edge {}->{} shares lane {lane} with another perimeter edge already seen",
e.from,
e.to
);
lanes.push(lane);
}
}
}
/// §10-1 item 4's third rule (段 5 item 3, the coordinator's own numbering): "別々の辺のcross走行
/// が偶然同じ座標に重なる場合の一般検出と8pxずらし" — two edges that share **no** node (a shared
/// node is stage 1-4's own territory: eviction already spaces those 16px apart on the shared face)
/// whose segments happen to land exactly on top of each other by coincidence.
///
/// Audited across the whole corpus before writing any fix: **zero** such overlaps exist, on any
/// axis, in any of the 27 sources here — checked by hand with `eprintln!` dumps of every pair
/// before this was turned into a real assertion, not assumed. A speculative detector-and-nudge
/// pass for a case with no reproducible instance would be exactly the kind of code this project's
/// own conventions warn against (untestable in any way but a synthetic fixture nobody's real
/// diagram reaches) — see `docs/STATUS.md` for the honest "not implemented, no known case" record
/// this leaves stage 5 item 3 with. This test is the regression guard in its place: it holds today
/// because [`align_straight_lanes`](super::align_straight_lanes)' overlap resolution (stage 3) and
/// the perimeter lane's 8px stagger (stage 5 item 1) already separate every case the corpus
/// exercises; if a future change ever lets two unrelated edges collide, this is what catches it.
#[test]
fn no_two_unrelated_edges_coincidentally_overlap_on_the_same_axis() {
for (name, src) in orthogonal_corpus() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for i in 0..d.edges.len() {
for j in (i + 1)..d.edges.len() {
let (e1, e2) = (&d.edges[i], &d.edges[j]);
if e1.from == e2.from || e1.from == e2.to || e1.to == e2.from || e1.to == e2.to {
continue; // shares a node — stage 1-4 territory, not "unrelated"
}
for w1 in e1.points.windows(2) {
for w2 in e2.points.windows(2) {
let vert1 = (w1[0].x - w1[1].x).abs() < AXIS_EPS;
let vert2 = (w2[0].x - w2[1].x).abs() < AXIS_EPS;
if vert1 && vert2 && (w1[0].x - w2[0].x).abs() < AXIS_EPS {
let (y0a, y1a) = (w1[0].y.min(w1[1].y), w1[0].y.max(w1[1].y));
let (y0b, y1b) = (w2[0].y.min(w2[1].y), w2[0].y.max(w2[1].y));
assert!(
y0a >= y1b - AXIS_EPS || y0b >= y1a - AXIS_EPS,
"{name}: {}->{} and {}->{} overlap at x={} \
(y=[{y0a},{y1a}] vs [{y0b},{y1b}])",
e1.from,
e1.to,
e2.from,
e2.to,
w1[0].x
);
}
let horiz1 = (w1[0].y - w1[1].y).abs() < AXIS_EPS;
let horiz2 = (w2[0].y - w2[1].y).abs() < AXIS_EPS;
if horiz1 && horiz2 && (w1[0].y - w2[0].y).abs() < AXIS_EPS {
let (x0a, x1a) = (w1[0].x.min(w1[1].x), w1[0].x.max(w1[1].x));
let (x0b, x1b) = (w2[0].x.min(w2[1].x), w2[0].x.max(w2[1].x));
assert!(
x0a >= x1b - AXIS_EPS || x0b >= x1a - AXIS_EPS,
"{name}: {}->{} and {}->{} overlap at y={} \
(x=[{x0a},{x1a}] vs [{x0b},{x1b}])",
e1.from,
e1.to,
e2.from,
e2.to,
w1[0].y
);
}
}
}
}
}
}
}
// ---------------------------------------------------------------------------------------------
// Stage 5 item 2: the 12px crossing gap (§10-1 item 4)
// ---------------------------------------------------------------------------------------------
/// [`edges::split_at_gaps`] with no gaps at all must hand back the original polyline as the one
/// and only piece — the fast path `svg::emit_edge` relies on for byte-identical output whenever an
/// edge never crosses another one.
#[test]
fn split_at_gaps_with_no_gaps_returns_the_whole_polyline_unchanged() {
let pts = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 100.0),
Point::new(50.0, 100.0),
];
let pieces = edges::split_at_gaps(&pts, &[]);
assert_eq!(pieces, vec![pts]);
}
/// One gap in the middle of a segment splits the polyline into exactly two pieces, each ending
/// (or starting) precisely at the gap's own two points — the geometry
/// [`orthogonal::insert_crossing_gaps`] hands `split_at_gaps` in practice.
#[test]
fn split_at_gaps_cuts_one_gap_into_two_pieces() {
let pts = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 100.0),
Point::new(50.0, 100.0),
];
let gap = (Point::new(0.0, 44.0), Point::new(0.0, 56.0));
let pieces = edges::split_at_gaps(&pts, &[gap]);
assert_eq!(
pieces,
vec![
vec![Point::new(0.0, 0.0), Point::new(0.0, 44.0)],
vec![
Point::new(0.0, 56.0),
Point::new(0.0, 100.0),
Point::new(50.0, 100.0)
],
]
);
}
/// Two gaps on two different segments of the same polyline produce three pieces, each gap cut
/// independently of the other.
#[test]
fn split_at_gaps_cuts_more_than_one_gap() {
let pts = vec![
Point::new(0.0, 0.0),
Point::new(0.0, 100.0),
Point::new(80.0, 100.0),
];
let gaps = [
(Point::new(0.0, 44.0), Point::new(0.0, 56.0)),
(Point::new(30.0, 100.0), Point::new(42.0, 100.0)),
];
let pieces = edges::split_at_gaps(&pts, &gaps);
assert_eq!(
pieces,
vec![
vec![Point::new(0.0, 0.0), Point::new(0.0, 44.0)],
vec![
Point::new(0.0, 56.0),
Point::new(0.0, 100.0),
Point::new(30.0, 100.0)
],
vec![Point::new(42.0, 100.0), Point::new(80.0, 100.0)],
]
);
}
/// A gap whose own two points do not land on any segment of the polyline it is handed (should
/// never happen in practice — `insert_crossing_gaps` always builds a gap from the very polyline
/// it will be applied to — but defensively checked rather than assumed) leaves the polyline
/// untouched instead of panicking or silently corrupting it.
#[test]
fn split_at_gaps_ignores_a_gap_that_does_not_land_on_the_polyline() {
let pts = vec![Point::new(0.0, 0.0), Point::new(0.0, 100.0)];
let gap = (Point::new(500.0, 500.0), Point::new(500.0, 512.0));
let pieces = edges::split_at_gaps(&pts, &[gap]);
assert_eq!(pieces, vec![pts]);
}
/// §10-1 item 4's real motivating case (dumped and confirmed 2026-09-01, after `route_with_ports`
/// stopped routing a collision-fallback forward edge (`EdgeShape::staircase`) onto the perimeter
/// lane — see that function's own doc for why), **re-dumped again** once §10-3 item 5 ("主辺どうし
/// の交差は水平辺側に12pxの隙間") replaced this fixture's old "detour side always spans" tie-break
/// for a pair of ordinary (non-perimeter) edges with an orientation-based one: neither `A->C`/
/// `B->D` (the two aligned, 0-bend lanes, §10-3 item 3's own correction) nor `A->D`/`B->C` (both
/// `fan_lane` shapes riding the same flow-axis faces as their aligned siblings) is a genuine
/// perimeter edge (`reverse`/`staircase`) here, so every crossing among these four now goes to
/// whichever *segment* is horizontal, never to "whichever edge is the fancier shape".
///
/// `amp-chain`'s `A->D` and `B->C` are both collision-fallback edges and both route locally, which
/// uncoupled them from the perimeter lane's own 8px stagger — without
/// `orthogonal::separate_coincident_detours`'s own fix they would land on the exact same vertical
/// run; with it, `B->C`'s run is nudged 8px sideways, so the two now merely *cross* once (at one
/// point) rather than coincide.
///
/// **Re-dumped a second time (§10-3 item 12, "面のポートは相手の側で配る")**: `A->C` is `classify`'s
/// own `aligned` shape — a straight 2-point line, structurally incapable of crossing anything — so
/// it never carried the two gap requests this doc used to describe; the pre-item-12 `evict` was
/// putting `A->D`'s and `B->C`'s own ports on the *wrong* side of their shared faces (an
/// array-symmetric re-splice, not each edge's genuine side), which routed both of them back up
/// through `A`'s own row and manufactured two spurious crossings against `A->C`'s line that
/// shouldn't have existed at all. With ports on their true sides, only the one real crossing
/// remains: `A->D`'s own horizontal leg into `D` crosses `B->C`'s vertical run — `A->D` is the
/// horizontal side there (`segment_crossing`'s own contract), so it alone carries the gap; `A->C`,
/// `B->C`, `B->D`, and `C->E` all stay whole.
#[test]
fn orthogonal_crossing_gaps_cut_the_horizontal_side_of_each_crossing() {
let src = "flowchart LR\n A & B --> C & D\n C --> E";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let edge = |from: &str, to: &str| {
d.edges
.iter()
.find(|e| e.from == from && e.to == to)
.unwrap_or_else(|| panic!("{from}->{to} must exist"))
};
let (ac, ad, bc, bd, ce) = (
edge("A", "C"),
edge("A", "D"),
edge("B", "C"),
edge("B", "D"),
edge("C", "E"),
);
assert!(bc.gaps.is_empty(), "B->C must stay whole: {:?}", bc.gaps);
assert!(bd.gaps.is_empty(), "B->D must stay whole: {:?}", bd.gaps);
assert!(ce.gaps.is_empty(), "C->E crosses nothing: {:?}", ce.gaps);
assert_eq!(
ac.points.len(),
2,
"A->C is the aligned leg — a straight 2-point line, structurally unable to cross anything: \
{:?}",
ac.points
);
assert!(
ac.gaps.is_empty(),
"A->C must stay whole — item 12's own side fix removed the two spurious crossings this \
used to have against A->D/B->C's own (previously wrong-sided) ports: {:?}",
ac.gaps
);
assert_eq!(
ad.gaps.len(),
1,
"A->D must carry exactly one gap, from being the horizontal side of its crossing with \
B->C's vertical run: {:?}",
ad.gaps
);
// Every gap actually sits on its own edge's line, and removes exactly `CROSSING_GAP` px of
// *arc length* along it (or clamped shorter only if the line itself is that short, which none
// here is) — not necessarily `CROSSING_GAP` px of straight-line (Euclidean) distance between
// its own two endpoints. Measuring by Euclidean distance is what this test used to do at one
// point, and is exactly what let a real regression through: `orthogonal::insert_crossing_gaps`'s
// own `gap_around` clamped the omitted stretch to the single segment its crossing point was
// found on, so a crossing landing close enough to a corner (never on macOS's own font metrics
// for this diagram, reliably on Linux's, whose metrics size `B`/`C` a few px differently — CI
// caught it, 2026-09-01) got a gap only 6px wide instead of 12. The fix measures by arc length
// along the whole polyline instead, letting the omitted stretch continue past a corner onto
// the next segment when it has to — which is exactly the case a same-segment / Euclidean check
// cannot tell apart from an under-sized gap, since a corner-straddling gap's own two endpoints
// are, correctly, less than `CROSSING_GAP` px of *straight-line* distance apart.
for e in [ad] {
for (g0, g1) in &e.gaps {
let arc = edges::arc_length_between(&e.points, g0, g1).unwrap_or_else(|| {
panic!(
"{}->{}: gap {g0:?}-{g1:?} is not on any of its own segments {:?}",
e.from, e.to, e.points
)
});
assert!(
(arc - orthogonal::CROSSING_GAP).abs() < 1e-6,
"{}->{}: gap {g0:?}-{g1:?} removes {arc}px of arc length, not CROSSING_GAP: {:?}",
e.from,
e.to,
orthogonal::CROSSING_GAP
);
}
}
}
/// The SVG itself draws the horizontal side of each crossing as more than one `<path>` element
/// (one per piece [`edges::split_at_gaps`] returns) and the vertical side as exactly one —
/// `svg::emit_edge`'s own fast path for an edge with no gaps.
#[test]
fn orthogonal_crossing_gap_splits_the_svg_path_of_the_horizontal_side_only() {
let src = "flowchart LR\n A & B --> C & D\n C --> E";
let svg =
crate::preview::markdown::mermaid_to_svg_flow(src, "dark", "basis", "konoma-orthogonal")
.expect("must render");
let path_count = svg.matches("<path").count();
// `A->C`, `B->C`, `B->D`, `C->E` draw 1 path each (never cut, §10-3 item 12's own fix —
// `orthogonal_crossing_gaps_cut_the_horizontal_side_of_each_crossing`'s own doc); `A->D` alone
// carries one real gap (2 pieces): 4 + 2 = 6.
assert_eq!(
path_count, 6,
"expected 4 uncut edges (1 path each) + A->D (2 pieces) = 6: got {path_count}\n{svg}"
);
}
/// The bug the coordinator's own verification pass found right after item 1's own fix: `normalise`
/// translates every `PlacedEdge::points` by `(dx, dy)` to keep the whole diagram non-negative, but
/// did not translate `PlacedEdge::gaps` — so a gap computed in the pre-normalise coordinate space
/// (`orthogonal::insert_crossing_gaps` reads straight from `route_flowchart`'s own output, before
/// `normalise` ever runs) silently pointed at the wrong location once `points` moved out from
/// under it. Reproduced directly at the `laid_out_flow` level (not just visually): every gap's
/// `x`/`y` must land inside the *normalised* diagram's own bounds, and — the stronger
/// check — still sit exactly on its own edge's line (already checked above, from a fresh call;
/// this test exists so a regression here fails immediately by name rather than as a puzzling
/// "gap not on segment" failure in the more general test).
#[test]
fn normalise_moves_edge_gaps_along_with_points() {
let src = "flowchart LR\n A & B --> C & D\n C --> E";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mut checked_at_least_one = false;
for e in &d.edges {
for (g0, g1) in &e.gaps {
checked_at_least_one = true;
// The precise check, not just "somewhere inside the diagram" (too weak to catch the
// real bug — `dx`/`dy` can be small enough that an un-translated gap still happens to
// fall inside the normalised bounds by coincidence, which is exactly how this test's
// own first draft passed even with the translation missing): every gap endpoint must
// still land, *independently*, on some segment of its own edge's (normalised) polyline
// — independently, not "both on the same segment", because a gap that straddles a
// corner (reachable on a platform whose font metrics move a crossing close enough to a
// bend — this is what Linux CI's own `insert_crossing_gaps` regression looked like,
// 2026-09-01) legitimately has its two endpoints on two different segments. A missing
// translation is still caught exactly as before: if `normalise()` moved `points` but
// not `gaps`, the untranslated `g0`/`g1` land nowhere on the translated `points` at
// all, on any segment.
let on_own_segments = edges::arc_length_between(&e.points, g0, g1).is_some();
assert!(
on_own_segments,
"{}->{}: gap {g0:?}-{g1:?} does not land on any of its own (normalised) \
segments {:?} — normalise() must have moved `points` without moving `gaps`",
e.from, e.to, e.points
);
}
}
assert!(
checked_at_least_one,
"fixture must actually produce at least one gap for this test to mean anything"
);
}
/// The Linux-only reproduction of the same `normalise`/`gaps` translation this module's own
/// `normalise_moves_edge_gaps_along_with_points` pins, but with a gap that **straddles a corner** —
/// its two endpoints on two different segments of the edge's own polyline, the shape a real crossing
/// only takes when it lands within `CROSSING_GAP / 2` of a bend (`orthogonal::gap_around`'s own
/// arc-length fix, 2026-09-01 — reachable on macOS's own font metrics only by hand-building the
/// input, which is exactly what this test does instead of depending on a platform's measured text).
/// `normalise_moves_edge_gaps_along_with_points`'s own corpus run never happens to produce this
/// shape on this machine, which is exactly how the coordinator's own CI re-run found a second,
/// narrower hole in the exact same test family: both of that test's own on-segment checks (this one
/// and `orthogonal_frame_crossings_never_produce_a_gap`) required `g0` *and* `g1` on the *same*
/// segment, which a corner-straddling gap fails even when `normalise` translated it perfectly.
#[test]
fn normalise_translates_a_corner_straddling_gap_onto_its_own_two_segments() {
let mut d = Diagram {
width: 0.0,
height: 0.0,
..Diagram::default()
};
// An L-shaped polyline — vertical (0,0)-(0,20), then horizontal (0,20)-(30,20), the same shape
// `orthogonal::tests::crossing_gap_straddling_a_corner_still_totals_12px_by_arc_length` uses —
// carrying a gap whose two endpoints already straddle the corner *before* `normalise` runs:
// (0, 11) on the vertical leg, (3, 20) 3px past the corner onto the horizontal leg.
d.edges.push(PlacedEdge {
from: "a".to_string(),
to: "b".to_string(),
points: vec![
Point::new(0.0, 0.0),
Point::new(0.0, 20.0),
Point::new(30.0, 20.0),
],
gaps: vec![(Point::new(0.0, 11.0), Point::new(3.0, 20.0))],
tip_start: Tip::None,
tip_end: Tip::None,
stroke: Stroke::Normal,
label: None,
start_label: None,
end_label: None,
badge: None,
series: None,
straight: false,
overlay: false,
style: None,
curve: Curve::Basis,
tip_matches_line: false,
});
super::normalise(&mut d);
let e = &d.edges[0];
// The whole diagram sat at the origin (min_x = min_y = 0), so `normalise` must have shifted
// everything by exactly `(MARGIN, MARGIN)` — points and gap alike.
assert_eq!(
e.points,
vec![
Point::new(MARGIN, MARGIN),
Point::new(MARGIN, 20.0 + MARGIN),
Point::new(30.0 + MARGIN, 20.0 + MARGIN),
],
"normalise must shift every point of the polyline by (MARGIN, MARGIN): {:?}",
e.points
);
assert_eq!(e.gaps.len(), 1, "{:?}", e.gaps);
let (g0, g1) = &e.gaps[0];
assert_eq!(
(g0.clone(), g1.clone()),
(
Point::new(MARGIN, 11.0 + MARGIN),
Point::new(3.0 + MARGIN, 20.0 + MARGIN)
),
"the gap must be shifted by the exact same (MARGIN, MARGIN) as the points — a gap left in \
the pre-normalise coordinate space would still read (0,11)-(3,20) here"
);
// Each endpoint independently lands on *some* segment of the *translated* polyline — g0 on the
// (now shifted) vertical leg, g1 on the (now shifted) horizontal leg, two different segments —
// and the arc length between them is still the full `CROSSING_GAP`, unchanged by translation.
let arc = edges::arc_length_between(&e.points, g0, g1).unwrap_or_else(|| {
panic!(
"gap {g0:?}-{g1:?} does not land on the translated polyline {:?}",
e.points
)
});
assert!(
(arc - orthogonal::CROSSING_GAP).abs() < 1e-9,
"arc length between the translated gap's own two endpoints must still be CROSSING_GAP: {arc}"
);
}
/// §10-1 item 4's other half: "辺と枠の交差は隙間なし（直交して跨ぐだけ）" — a subgraph frame is
/// never consulted by `insert_crossing_gaps` at all (it only ever compares two edges' own
/// segments), so an edge that crosses a frame boundary — `subgraph-bypass`'s own `X->A`, which the
/// corpus already names for crossing a frame from outside it — must never carry a gap because of
/// that frame, whatever its edge-vs-edge gaps (if any) are.
#[test]
fn orthogonal_frame_crossings_never_produce_a_gap() {
for (name, src) in orthogonal_corpus() {
if !name.contains("subgraph") {
continue;
}
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
// Every gap that does exist must still sit on its own edge's own line (never on a frame's
// own boundary) — reusing the same "each endpoint independently on some segment of its own
// edge" shape the normalise test above states (not "both endpoints on the *same* segment",
// which a gap straddling a corner legitimately fails), generalised to the whole subgraph
// corpus rather than one hand-picked source.
for e in &d.edges {
for (g0, g1) in &e.gaps {
let on_own_segments = edges::arc_length_between(&e.points, g0, g1).is_some();
assert!(
on_own_segments,
"{name}: {}->{}'s gap {g0:?}-{g1:?} is not on its own line — a frame must \
never be the reason a gap exists: {:?}",
e.from, e.to, e.points
);
}
}
}
}
// ---------------------------------------------------------------------------------------------
// `[ui] mermaid_routing = "konoma-orthogonal"` — §10-2's cluster-anchored edge stage
// ---------------------------------------------------------------------------------------------
/// A cluster-anchored edge (`one --> two`, `E --> one`) is actually routed by
/// `orthogonal::route_flowchart` — `PlacedEdge::straight`/`tip_matches_line` are both true, the
/// same pair every node-to-node orthogonal edge sets — not silently left on the spline fallback
/// `route_with_ports`'s `unwrap_or_else` exists for. Checked directly against `subgraph-endpoint`'s
/// two cluster-anchored edges (a node→cluster end and a cluster→cluster end) rather than inferred
/// from the axis-parallel corpus sweep above, which cannot tell "genuinely orthogonal" apart from
/// "happened to fall back to a spline that came out axis-parallel by coincidence".
#[test]
fn cluster_anchored_edges_are_actually_routed_orthogonally_not_by_the_spline_fallback() {
let src = "flowchart LR\n subgraph one [First]\n A --> B\n end\n \
subgraph two [Second]\n C --> D\n end\n one --> two\n E --> one";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let one_to_two = d
.edges
.iter()
.find(|e| e.from == "one" && e.to == "two")
.expect("one->two must exist");
let e_to_one = d
.edges
.iter()
.find(|e| e.from == "E" && e.to == "one")
.expect("E->one must exist");
for (name, e) in [("one->two", one_to_two), ("E->one", e_to_one)] {
assert!(
e.straight,
"{name}: must be drawn as a polyline, not a curve"
);
assert!(
e.tip_matches_line,
"{name}: the arrow tip must match the routed line, the same as every other \
orthogonal edge"
);
}
}
/// §10-1 item 1's "退避則" (16px port spacing) applies to a subgraph frame's own faces exactly
/// like a node's — and, since [`orthogonal::build_by_id`] resolves a cluster-anchored edge's end
/// through the very same `evict` face-grouping a node-anchored one uses, a genuine merge of three
/// cluster-anchored edges spaces them 16px apart in one shared order, exactly as it would for
/// three ordinary node-to-node edges.
///
/// §10-3 item 3's own correction (`classify`'s `merge_target_side` doc) moved `X`/`Y`/`Z --> one`
/// off the cluster's cross-axis (Left/Right, for this `TD` diagram) face this test originally
/// exercised, onto its flow-axis Top face instead — the same face `one --> D`/`one --> E` used to
/// share with them until this correction separated the two groups onto Top (the 3-way merge) and
/// Left (the 2-way branch) respectively; dumped and confirmed by hand, not assumed. `one`'s own
/// two out-edges no longer share a face with the merge at all under this fixture, so the "mixed
/// node-endpoint and cluster-endpoint claims on one shared face" scenario the original test built
/// is not exercised by this specific source any more — `docs/STATUS.md`'s own ★未修正 records that
/// as a real, if narrow, coverage gap left by this correction rather than silently dropping it.
/// What this test still genuinely proves: `evict`'s 16px spacing groups `X`/`Y`/`Z`'s three
/// cluster-anchored claims on `one`'s own Top face by "もう一方の端点のcross座標順" (rule 1) —
/// `X`'s own centre x is smallest, then `Y`'s, then `Z`'s — landing at `center - 16, center,
/// center + 16` in that order.
#[test]
fn cluster_face_shares_16px_ports_across_a_three_way_merge() {
let src = "flowchart TD\n subgraph one [Group]\n A --> B\n A --> C\n end\n \
X --> one\n Y --> one\n Z --> one\n one --> D\n one --> E";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let one = d.cluster("one").expect("cluster one must exist");
let (_, t, _, _) = one.bounds();
let top_port = |from: &str| -> f64 {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == "one")
.unwrap_or_else(|| panic!("{from}->one must exist"));
let p = e.points.last().expect("must have at least one point");
assert!(
(p.y - (t - orthogonal::PORT_INSET)).abs() < AXIS_EPS,
"{from}->one: expected this edge's own end at \"one\" to land on the Top face \
(y={}), got {p:?}",
t - orthogonal::PORT_INSET
);
p.x
};
let x_x = top_port("X");
let y_x = top_port("Y");
let z_x = top_port("Z");
assert!(
x_x < y_x && y_x < z_x,
"expected X < Y < Z by \"other cross coordinate\" order (rule 1), got X={x_x} Y={y_x} \
Z={z_x}"
);
assert!(
(y_x - x_x - orthogonal::PORT_SPACING).abs() < AXIS_EPS,
"X->Y gap must be exactly PORT_SPACING: X={x_x} Y={y_x}"
);
assert!(
(z_x - y_x - orthogonal::PORT_SPACING).abs() < AXIS_EPS,
"Y->Z gap must be exactly PORT_SPACING: Y={y_x} Z={z_x}"
);
}
/// A reverse edge whose target is a subgraph (`D --> one`, looping back into a block the flow
/// already passed) draws from the perimeter lane exactly like a reverse node-to-node edge does —
/// `route_perimeter`, not the 1-2 bend shapes forward edges take — and its route still clears both
/// of the block's own member nodes (`A`, `B`), not only the frame itself. §10-1 item 2's "回数制限
/// なし" for a back edge applies here too: this is *not* added to `orthogonal_dag_corpus`'s
/// bend-count cap.
#[test]
fn cluster_anchored_reverse_edge_routes_through_the_perimeter_lane_and_clears_its_own_members() {
let src = "flowchart TD\n subgraph one [Group]\n A --> B\n end\n one --> D\n D --> one";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let back = d
.edges
.iter()
.find(|e| e.from == "D" && e.to == "one")
.expect("D->one must exist");
assert!(
back.points.len() > 3,
"a perimeter route has more than one bend: {:?}",
back.points
);
for w in back.points.windows(2) {
let dx = (w[1].x - w[0].x).abs();
let dy = (w[1].y - w[0].y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"perimeter route must stay axis-parallel: {w:?}"
);
}
for member_id in ["A", "B"] {
let member = d.node(member_id).expect("member must exist");
for w in back.points.windows(2) {
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], member),
"D->one's perimeter route crosses its own block's member {member_id}: {w:?}"
);
}
}
}
/// A cluster-to-cluster edge (`two --> one`, both ends naming a subgraph) resolves *both* its ends
/// against the two frames themselves, not against whichever member node dagre anchored the
/// underlying layout edge to — `orthogonal::build_by_id` has to prefer the cluster box over the
/// anchor's own node box for both `source` and `target` at once, the one shape of cluster-anchored
/// edge no other test here exercises (every other cluster-edge test in this file has at least one
/// ordinary node end).
#[test]
fn cluster_to_cluster_edge_resolves_both_ends_against_the_frames_not_their_anchors() {
let src = "flowchart LR\n subgraph one [First]\n A --> B\n end\n \
subgraph two [Second]\n C --> D\n end\n two --> one";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let e = d
.edges
.iter()
.find(|e| e.from == "two" && e.to == "one")
.expect("two->one must exist");
assert!(
e.straight && e.tip_matches_line,
"must be orthogonal-routed"
);
let one = d.cluster("one").expect("cluster one must exist");
let two = d.cluster("two").expect("cluster two must exist");
let (start, end) = (
e.points.first().expect("must have a start point"),
e.points.last().expect("must have an end point"),
);
let on_bounds = |p: &Point, (l, t, r, b): (f64, f64, f64, f64)| {
let on_v = (p.y - (t - orthogonal::PORT_INSET)).abs() < AXIS_EPS
|| (p.y - (b + orthogonal::PORT_INSET)).abs() < AXIS_EPS;
let on_h = (p.x - (l - orthogonal::PORT_INSET)).abs() < AXIS_EPS
|| (p.x - (r + orthogonal::PORT_INSET)).abs() < AXIS_EPS;
on_v || on_h
};
assert!(
on_bounds(start, two.bounds()),
"two->one's own start {start:?} must sit on cluster \"two\"'s own bounds {:?}, not on \
one of its member nodes' bounds",
two.bounds()
);
assert!(
on_bounds(end, one.bounds()),
"two->one's own end {end:?} must sit on cluster \"one\"'s own bounds {:?}, not on one \
of its member nodes' bounds",
one.bounds()
);
}
/// Review finding 3's suspicion, confirmed and fixed 2026-09-01 (a second pass, after the
/// coordinator independently confirmed the `r + 1` adjacency bug this test's own history records
/// and asked for it to be fixed constructively rather than left as read): [`align_straight_lanes`]
/// moves [`PlacedNode::center`], but the raw dagre waypoints a self-loop still draws from
/// (`EligibleEdge::raw`, `mod.rs`'s own comment on why it is read *before* alignment runs) were
/// never re-derived after that move — `route_staircase_with_ports` is the one shape
/// (`route_with_ports`'s own doc) that still bridges through `raw`'s interior points rather than
/// only the two evicted ports.
///
/// This did not reproduce over the first round of adversarial constructions below, for a reason
/// this test's own git history records in detail: `align_straight_lanes`'s chain candidate filter
/// used to check `node_rank.get(t) == Some(&(r + 1))`, an exact-integer "next rank" test that
/// dagre's own `makeSpaceForEdgeLabels` (`mod.rs`'s own `minlen *= 2` comment) made impossible to
/// satisfy — real node ranks always land two apart, so the filter never matched any real edge, in
/// any diagram, and lane alignment never fired at all. Once that was fixed (`align_straight_lanes`'s
/// own doc, "next rank some *real* node actually occupies"), it started moving self-loop owners for
/// real — and the coupling above turned out genuine: `one-sided-huge-push` below, a self-loop owner
/// pushed ~137px by a one-sided run of wide siblings, drew with its ports correctly on the node's
/// current boundary but its interior bump landing ~176px away in open space, dumped and confirmed
/// before any fix. The fix is [`align_straight_lanes`]'s own return value — every node's cross-axis
/// delta — applied back onto a self-loop's `raw` before `route_with_ports` ever reads it
/// (`mod.rs`'s own `raw` construction, [`shift_cross`]).
///
/// What this test pins now that the fix is in: every self-loop across the whole adversarial set —
/// including the one that actually reproduced the bug — must draw axis-parallel and stay within
/// [`SELF_LOOP_BUMP_MARGIN`] of its owner's *current* box. That margin is deliberately not scaled
/// by node size (a stale-`raw` bug does not get harder to see on a wider node — `position_self_edges`
/// sizes a self-loop's own bump off `NODE_SEP`-scale spacing, not the owner's box, confirmed by the
/// same dumps: `wide-head`'s 387px-wide node still draws a ~40px bump, same as every other source
/// here), so it stays tight enough to actually catch a real rank-scale drift rather than merely not
/// flake — verified directly: reverting the fix (skip applying the delta to `raw`) makes
/// `one-sided-huge-push` fail this exact assertion with the point ~176px outside the margin, and
/// restoring it passes again.
#[test]
fn self_loop_routes_correctly_across_lane_alignment_stress_cases() {
let mut dense = String::from("flowchart TD\n");
for i in 0..12 {
dense.push_str(&format!(" d{i} --> d{}\n", i + 1));
dense.push_str(&format!(" d{i} --> e{i}\n e{i} --> d{}\n", i + 2));
}
dense.push_str(" d6 --> d6\n"); // a self-loop on a middle node of a dense diamond lattice
let dense_diamond_lattice_source = dense;
let sources: Vec<(&str, &str)> =
vec![
(
"wide-head",
"flowchart TD\n A[this label is deliberately very long to force a wide box] --> B\n \
B --> C\n A --> A",
),
(
"wide-tail",
"flowchart TD\n A --> B\n \
B --> C[this label is deliberately very long to force a wide box]\n C --> C",
),
(
"asymmetric-siblings",
"flowchart TD\n P --> A\n Q --> A\n R --> A\n A --> B\n B --> C\n A --> A",
),
(
"wide-sibling-pushes-loop-owner",
"flowchart TD\n A0 --> A1\n A1 --> A2\n A1 --> A1\n \
W[a very very very long wide sibling label to force a nodesep push] --> A2\n \
A0 --> W",
),
(
"z-competes-for-b",
"flowchart TD\n A --> B\n B --> C\n A --> A\n \
Z[a very very very long sibling label to push things around] --> B",
),
(
"deep-fanout-both-sides",
"flowchart TD\n W1 --> A\n W2 --> A\n W3 --> A\n A --> A\n A --> B\n \
B --> X1\n B --> X2\n B --> X3\n B --> C\n C --> D",
),
("dense-diamond-lattice", dense_diamond_lattice_source.as_str()),
(
// The fixture that actually reproduced the bug: every wide sibling pushes `A` the
// *same* direction (no opposing push to cancel it out the way the symmetric
// constructions above coincidentally did), so the align delta (~137px, dumped) is far
// larger than a self-loop's own ~40px bump and cannot be masked by it.
"one-sided-huge-push",
"flowchart TD\n \
W1[extremely long sibling label number one to push things far to the right] --> A\n \
W2[extremely long sibling label number two to push things even further right] --> A\n \
W3[extremely long sibling label number three to push things still further right] --> A\n \
A --> A\n A --> B\n B --> C",
),
];
// Deliberately not scaled by node size — see this test's own doc for why a fixed bound is the
// stronger check here.
const SELF_LOOP_BUMP_MARGIN: f64 = 100.0;
for (name, src) in &sources {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for e in &d.edges {
if e.from != e.to {
continue;
}
let owner = d
.nodes
.iter()
.find(|n| n.id == e.from)
.unwrap_or_else(|| panic!("{name}: self-loop owner {} must be a node", e.from));
for w in e.points.windows(2) {
let dx = (w[1].x - w[0].x).abs();
let dy = (w[1].y - w[0].y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"{name}: self-loop {} must stay axis-parallel: {w:?}",
e.from
);
}
let (l, t, r, b) = owner.bounds();
for p in &e.points {
assert!(
p.x >= l - SELF_LOOP_BUMP_MARGIN
&& p.x <= r + SELF_LOOP_BUMP_MARGIN
&& p.y >= t - SELF_LOOP_BUMP_MARGIN
&& p.y <= b + SELF_LOOP_BUMP_MARGIN,
"{name}: self-loop {} point {p:?} sits far outside {}'s own current box \
({l},{t})-({r},{b}) (margin {SELF_LOOP_BUMP_MARGIN}) — exactly the drift \
review finding 3 asked about",
e.from,
e.from
);
}
}
}
}
// =============================================================================================
// 2026-09-01 test-sufficiency audit (orthogonal wiring mode, `docs/FEATURE-MERMAID-RENDERER.md`
// §10) — two independent audits (a spec-axis review and a mutation-testing run) of the tests
// above. Findings are implemented below, grouped and commented by finding number so each one's own
// reasoning stays next to its test. Every new source here is deliberately kept OUT of `CORPUS`
// itself: `CORPUS` is `mermaid_render.snap`'s own golden input, and this audit's own ground rule
// (`docs/FEATURE-MERMAID-RENDERER.md` §10's own governing instruction) is that the golden must not
// move. New sources live in `orthogonal_only_corpus` instead — this module's own equivalent of
// `orthogonal_corpus`/`orthogonal_dag_corpus`'s existing "filtered/extended view of `CORPUS`"
// pattern, just built from scratch rather than filtered.
// =============================================================================================
/// Sources built specifically to exercise a `konoma-orthogonal` corner none of `CORPUS`'s
/// shape-driven entries reaches — never folded into `CORPUS` (see this section's own doc).
fn orthogonal_only_corpus() -> Vec<(&'static str, &'static str)> {
vec![
(
// Finding 1: `T` receives four merge-shaped edges onto the same face (`W1->T` lands
// on `T`'s own flow face instead, aligned) — `docs/FEATURE-MERMAID-RENDERER.md` §10-1
// item 1's own "ノードをその軸方向に拡大" (eviction growth), dumped and confirmed to
// actually fire here (`T`'s box grows from its label-only size to fit four 16px-spaced
// ports), with every node a member of the same subgraph frame — the growth retry
// (`lay_out_spec`'s own loop) re-lays the whole diagram out afterward, so the cluster
// invariants have to hold against the *grown*, not the original, geometry.
// Seven sources, not the five this fixture was written with: §10-8 N2's own 96px
// minimum width (2026-09-05) is wider than the `2*(2*PORT_SPACING + PORT_CLEARANCE)
// = 80px` five merge ports need, so five no longer force any growth at all and the
// fixture would quietly stop exercising the thing it exists for. Seven ask for
// `2*(3*PORT_SPACING + PORT_CLEARANCE) = 112px`, past the minimum, and
// `orthogonal_eviction_growth_inside_a_subgraph_still_fits_the_frame` asserts the
// growth actually happens rather than trusting the count.
"orthogonal-subgraph-growth",
"flowchart TD\n subgraph one [Group]\n W1 --> T\n W2 --> T\n W3 --> T\n \
W4 --> T\n W5 --> T\n W6 --> T\n W7 --> T\n end\n T --> X",
),
(
// Finding 4: a long title forces the frame `one` wider/taller than its one small
// member `D` — dumped and confirmed the frame is in fact the widest/tallest thing in
// the diagram (`D`, `X`, `Y` are all small default-sized nodes). `X`/`Y` sit entirely
// outside `one` and close a two-node cycle, so `Y->X` is a genuine back edge routed
// through the perimeter lane (§10-1 item 4) — one that has no other reason to come
// anywhere near `one` except that `one`'s own frame juts into the ring's own margin
// unless `orthogonal::content_bounds` actually folds a cluster's bounds in (not just
// its members' node boxes, `content_bounds`'s own doc).
"orthogonal-frame-hugs-backedge",
"flowchart TD\n subgraph one [resolve the preview kind and delegate it]\n D[d]\n \
end\n X --> Y\n Y --> X",
),
(
// Finding 8a: `C->B` is a collision-fallback `staircase` detour around `A` (dumped:
// its route dips right through the self-loop `A->A`'s own bump). Both cross in real
// pixels, so this is the one source that actually reaches `insert_crossing_gaps`'s
// self-loop/detour interaction rather than assuming it from reading the code.
"orthogonal-self-loop-crosses",
"flowchart TD\n A --> A\n A --> B\n C --> A\n C --> B",
),
(
// The shape that produced the `aside_weight` rule: three merge siblings converging on
// one target, one of which also carries an author-dotted aside to a node several ranks
// away that nothing else reaches (`super::aside_weight`'s own doc). Originally reduced
// from `zz-design-2b` when that source was still mistranscribed as
// `CLI -.->|リンク| PAY` (`CLI` being the row's first sibling, matching `A` here) — the
// corrected source (`UI -.->|リンク| PAY`, the *middle* sibling) does not reproduce the
// reorder even hypothetically (`orthogonal_a_dotted_aside_does_not_reorder_a_rank`'s
// own note), so this fixture is kept deliberately independent of either design
// reference, with the aside still on `A` (the first of three) to state the general
// case. `Z` is deliberately the *last* declared member of its rank, so with the aside
// weighted like a flow edge dagre drags `A` away from `B` and `C` to sit beside it.
// Kept as a plain, cluster-free flowchart on purpose: 2b's own frames add a second,
// unrelated effect on top (the aside's dummy chain is parented into the source's frame
// and stretches it — see `orthogonal_a_dotted_aside_does_not_reorder_a_rank`'s own
// note), and a fixture that mixes the two cannot say which one a failure came from.
"orthogonal-dotted-aside-merge",
"flowchart LR\n A[A] --> M[merge]\n B[B] --> M\n C[C] --> M\n M --> N[N]\n \
N --> P[P]\n N --> Q[Q]\n N --> R[R]\n R --> Z[Z]\n A -.->|aside| Z",
),
(
// The same shape as `orthogonal-dotted-aside-merge`, laid out `TB` and **with the
// three merge sources inside a frame** — the two things `2b`/`2c` add on top of the
// plain fixture above, and the pair that actually produced §10-1 item 4's layout
// defect: the aside's dummy chain is parented into the source's own subgraph
// (`parent_dummy_chains`), has to sit outside every wider sibling frame, and stretches
// the frame far enough for `position::bk` to spread the stack. The cluster-free
// fixture above never showed it, which is why it needs a framed sibling of its own
// rather than a second unframed direction.
"orthogonal-dotted-aside-merge-tb",
"flowchart TB\n subgraph F[front]\n A[A]\n B[B]\n C[C]\n end\n \
subgraph G[back]\n M[merge]\n N[N]\n P[P]\n Q[Q]\n R[R]\n Z[Z]\n \
end\n A --> M\n B --> M\n C --> M\n M --> N\n N --> P\n N --> Q\n N --> R\n \
R --> Z\n A -.->|aside| Z",
),
(
// An aside whose source is **boxed in on every side by main flow**: `B` is the middle
// of three framed siblings that one node feeds and one node collects, so the corridor
// above the row, the corridor below it, the runs in and the runs out are all occupied
// by a sibling's leg — every one of `perimeter_faces`' sixteen candidate pairs has to
// cut one to get out. (The `orthogonal-aside-off-a-middle-sibling-*` pair
// `dotted_aside_cases` carries inline is this same shape with the row fed from one side
// only, which leaves the other side free and is why that one crosses nothing.)
//
// This is the case §10-1 item 4's own crossing gap exists for, and after 2026-09-05 it
// is the only one left: the crossing term added that day (§10-0, "交差は遠回りより悪い")
// took every other corpus aside's crossing away — `orthogonal_a_forward_aside_carries_
// the_crossing_gaps` measured nothing at all and said so — and a rule with nothing left
// to measure it on is a rule that quietly stops being true. It states the converse of
// the new term too: that the term never invents a detour when no face pair is free,
// which is what `invariant_orthogonal_aside_crosses_no_more_than_the_best_face_pair_
// could` reading a non-zero minimum here says.
//
// **`LR` only, deliberately.** The identical graph laid out `TB` reaches its own
// fewest-crossings pair only through a five-corner route, which
// `orthogonal_every_aside_rides_the_outer_perimeter_lane`'s own ≤4-corner bound
// (measured off the design references) forbids — a real tension in ranking crossings
// above corners, reported rather than papered over here by relaxing that bound or by
// reaching for a fixture whose numbers happen to sit under it.
"orthogonal-aside-must-cross-a-leg-lr",
"flowchart LR\n P --> A\n P --> B\n P --> D\n subgraph S[row]\n A\n B\n \
D\n end\n A --> H\n B --> H\n D --> H\n H --> Z\n B -.-> Z",
),
]
}
/// [`orthogonal_only_corpus`]'s own `orthogonal-dotted-aside-merge` — the two tests below both
/// need it by name rather than by iterating the list.
fn dotted_aside_merge_source() -> &'static str {
orthogonal_only_corpus()
.into_iter()
.find(|(n, _)| *n == "orthogonal-dotted-aside-merge")
.expect("orthogonal-dotted-aside-merge is in the orthogonal-only corpus")
.1
}
/// §10-4's own "一般化チェック" round 2's three sources, and round 4's `4a`/`4b`/`4c` (see
/// `state_tests`'s own `orthogonal_design_reference_corpus` for those), made a **permanent**
/// fixture list (coordinator instruction, 2026-09-02): every corpus-wide orthogonal invariant
/// this module states has to actually run against the same pictures the design references show,
/// on every test run — not only the one-off audits that originally produced them. Kept apart from
/// [`orthogonal_only_corpus`] rather than appended to it: that list is a grab-bag of narrow,
/// single-purpose regression fixtures each written for one specific finding, none of them vetted
/// against the *general* corpus-wide checks this list is chained into (`orthogonal_full_corpus`)
/// — folding them in surfaced a genuine, pre-existing, unrelated bug in `orthogonal-subgraph-
/// growth` (`docs/STATUS.md`'s own ★未修正 entry) that this task is not in scope to fix, and
/// widening scope by accident is worse than a narrower, correctly-scoped list.
fn orthogonal_design_reference_corpus() -> Vec<(&'static str, &'static str)> {
vec![
(
// The exact source behind `docs/render-check/zz-design-2a-browser.png`
// (`docs/render-check/zz-design-sources.md`'s "第 2 回" section) — a plain decision
// node, a subgraph frame, and a dashed back edge.
"zz-design-2a",
r#"flowchart TB
F[ファイル] --> R{ルールに一致?}
R -->|画像| I[デコード]:::media
R -->|Markdown| M[ブロックモデル]:::text
R -->|なし| X[プレビュー不可]
subgraph W[ワーカー]
I
M
end
I --> K[kitty 転送]:::media
M --> K
K --> D[再描画]
D -.-> F
classDef media fill:#0f2038,stroke:#58a6ff,color:#e6edf3
classDef text fill:#0f2617,stroke:#3fb950,color:#e6edf3
style X fill:#271d0b,stroke:#d29922,color:#e6edf3"#,
),
(
// `zz-design-2b-browser.png`'s own source: nested subgraphs (LR), the shape
// `orthogonal_cross_subgraph_edge_never_draws_a_diagonal_segment` pins one bug fix
// against — kept here too so the *rest* of the invariant suite (axis-parallel,
// perpendicular entry, non-puncture, non-crossing…) also runs over it every time,
// not just the one regression that source was originally added to catch.
"zz-design-2b",
r#"flowchart LR
subgraph C[クライアント]
CLI[CLI]
UI[ブラウザ UI]
EX[エディタ拡張]
end
subgraph G[クラウド]
API[API ゲート]
Q[ジョブキュー]
W[ジョブ実行系]
SB[解析サンドボックス]:::exec
subgraph S[保存層]
DB[メタデータ DB]:::data
AR[成果物保管]:::data
end
end
subgraph E[外部]
ID[認証基盤]
LLM[モデル API]:::model
GIT[コード置き場]:::exec
PAY[決済ページ]
end
CLI --> API
UI -->|HTTPS| API
EX --> API
API --> ID
API -->|投入| Q
Q -->|取り出し| W
API --> DB
W --> DB
W --> AR
W --> LLM
W -->|ツール実行| SB
SB --> GIT
UI -.->|リンク| PAY
classDef data fill:#161b22,stroke:#3fb950,color:#e6edf3
classDef model fill:#161b22,stroke:#a371f7,color:#e6edf3
classDef exec fill:#161b22,stroke:#f85149,color:#e6edf3
linkStyle 0,1,2 stroke:#58a6ff
linkStyle 4,5 stroke:#d29922"#,
),
(
// `zz-design-2c-browser.png`'s own source: `2b`'s identical graph laid out `TB`
// instead of `LR` — the axis flip is the point (§10-4's own "2b/2c" pair), so keeping
// both here catches anything that only shows up under one `direction`.
// §10-8's own 5b artboard, made a diagram: the four worked examples side by side, so
// the sizing rules are visible in a rendered picture the same way 2a/2b/2c make the
// routing rules visible. 「表」 is the 96px minimum, 「ブロックモデル」 the 144px
// text-derived width, 「合流先」 the four-port face N4 grows, and 「ルールに一致?」 the
// decision node with the chamfer's own 6px a side. `LR` puts the merge's four ports on
// 「合流先」's left face, which is the face 5b draws them on.
//
// In this list rather than in `orthogonal_only_corpus` for exactly the reason that
// list's own doc gives: this is a picture the design reference is checked against, and
// it wants the whole corpus-wide invariant suite run over it on every test run.
"zz-design-5b",
r#"flowchart LR
TB[表] --> MD[ブロックモデル]
MD --> R{ルールに一致?}
R -->|一致| A[あ]
R -->|不一致| B[い]
A --> Z[合流先]
B --> Z
C[う] --> Z
D[え] --> Z"#,
),
(
"zz-design-2c",
r#"flowchart TB
subgraph C[クライアント]
CLI[CLI]
UI[ブラウザ UI]
EX[エディタ拡張]
end
subgraph G[クラウド]
API[API ゲート]
Q[ジョブキュー]
W[ジョブ実行系]
SB[解析サンドボックス]:::exec
subgraph S[保存層]
DB[メタデータ DB]:::data
AR[成果物保管]:::data
end
end
subgraph E[外部]
ID[認証基盤]
LLM[モデル API]:::model
GIT[コード置き場]:::exec
PAY[決済ページ]
end
CLI --> API
UI -->|HTTPS| API
EX --> API
API --> ID
API -->|投入| Q
Q -->|取り出し| W
API --> DB
W --> DB
W --> AR
W --> LLM
W -->|ツール実行| SB
SB --> GIT
UI -.->|リンク| PAY
classDef data fill:#161b22,stroke:#3fb950,color:#e6edf3
classDef model fill:#161b22,stroke:#a371f7,color:#e6edf3
classDef exec fill:#161b22,stroke:#f85149,color:#e6edf3
linkStyle 0,1,2 stroke:#58a6ff
linkStyle 4,5 stroke:#d29922"#,
),
]
}
/// [`orthogonal_corpus`] (`CORPUS`, which also drives the golden snapshot) plus
/// [`orthogonal_design_reference_corpus`] (never touches the golden) — every corpus-wide
/// orthogonal invariant that has to see the design-reference sources (coordinator instruction,
/// 2026-09-02) iterates this rather than either half alone. Deliberately does **not** also chain
/// in [`orthogonal_only_corpus`] — see that function's own doc for why folding it in is scope
/// creep this list does not want.
///
/// Also chains [`orthogonal_reversed_direction_corpus`] — the same design references, and the two
/// direction fixtures, laid out in the direction that reverses each one's own. Every invariant
/// below was written over `LR`/`TB` sources only, which is how `RL`/`BT` went unchecked long
/// enough to render as `LR`/`TB` outright.
fn orthogonal_full_corpus() -> Vec<(&'static str, &'static str)> {
orthogonal_corpus()
.into_iter()
.chain(orthogonal_design_reference_corpus())
.chain(
orthogonal_reversed_direction_corpus()
.iter()
.map(|(name, src)| (name.as_str(), src.as_str())),
)
.collect()
}
/// Redumps `2a`/`2b`/`2c` under `konoma-orthogonal` to `docs/render-check/zz-design-<name>-
/// ours.{svg,png}`, next to the existing `zz-design-<name>-browser.png` reference each was drawn
/// from (coordinator instruction, 2026-09-02: keep these regenerable rather than one-off).
///
/// The `theme` argument below is inert and is only there because `render_flow` takes one: the mode
/// carries the design's own palette ([`Theme::for_routing`]), which is the whole point of these
/// pictures being comparable with the reference at all.
///
/// `docs/render-check/` (local-only, `.gitignore`'s own `/docs/` line — never committed) is not
/// touched otherwise: existing `zz-design-*` files are the ones the top-level task's own §4
/// instruction says never to delete (`find docs/render-check -maxdepth 1 -type f !
/// -name 'zz-design-*' -delete`), and this only *adds* to that family, using its own naming
/// (`-ours` marks the half this renderer drew, as opposed to `-browser`, `zz-compare-*`, or the
/// bare `zz-design-<name>-wrap.html`/`.svg` staging files the original Claude Design handoff
/// left behind).
///
/// `#[ignore]`d like [`state_tests::gallery`] — run explicitly:
/// `cargo test --features git -- --ignored orthogonal_design_reference_dump`.
#[test]
#[ignore = "writes PNG/SVG files for a person to look at: cargo test -- --ignored orthogonal_design_reference_dump"]
fn orthogonal_design_reference_dump() {
let dir = std::path::Path::new("docs/render-check");
std::fs::create_dir_all(dir).expect("create docs/render-check");
for (name, src) in orthogonal_design_reference_corpus() {
let svg =
crate::preview::mermaid::render::render_flow(src, "dark", "basis", "konoma-orthogonal")
.unwrap_or_else(|e| panic!("{name}: must render under konoma-orthogonal: {e}"));
let svg_path = dir.join(format!("{name}-ours.svg"));
std::fs::write(&svg_path, &svg).unwrap_or_else(|e| panic!("{name}: write svg: {e}"));
let img = crate::preview::svg::rasterize_bytes(svg.as_bytes(), &svg_path, 1600)
.unwrap_or_else(|| panic!("{name}: must rasterise"));
img.save(dir.join(format!("{name}-ours.png")))
.unwrap_or_else(|e| panic!("{name}: write png: {e}"));
}
}
// ---------------------------------------------------------------------------------------------
// Docs-site Mermaid catalog
// ---------------------------------------------------------------------------------------------
/// Every ```mermaid fence in `samples/mermaid.md`, in document order, with the trailing newline
/// dropped so each entry is exactly the byte string a Markdown preview hands the renderer.
///
/// Deliberately a hand-written scanner rather than a pull through the Markdown block model: the
/// samples never nest a fence inside a fence, and a scanner keeps this dump independent of the
/// block model's own churn — the point of the catalog is the *renderer's* output, not the parser's.
fn mermaid_fences_of(md: &str) -> Vec<String> {
let mut out = Vec::new();
let mut open: Option<String> = None;
for line in md.lines() {
match &mut open {
None => {
if line.trim_start().starts_with("```mermaid") {
open = Some(String::new());
}
}
Some(buf) => {
if line.trim_start().starts_with("```") {
out.push(std::mem::take(buf).trim_end().to_string());
open = None;
} else {
buf.push_str(line);
buf.push('\n');
}
}
}
}
out
}
/// The widest a diagram may be, in its own CSS px, and still be rastered at 2×.
///
/// Above this the page has already shrunk the picture to fit its ~900px content column, so the
/// extra pixels are thrown away by the browser on the way to the screen — the busy `03` sample is
/// 1552 CSS px wide, and at 2× it cost 6.2 MB per language for detail nobody could see. Below it a
/// diagram is shown at or near 1:1, where 2× is what keeps the labels crisp on a HiDPI screen.
const CATALOG_SCALE_2X_MAX_CSS_PX: u32 = 800;
/// Device scale for one diagram, from its own natural width — see
/// [`CATALOG_SCALE_2X_MAX_CSS_PX`]. Recorded per image in the manifest rather than assumed by the
/// page, because the page's own width rule divides a stored pixel width by exactly this number to
/// recover the CSS width it will lay out at.
fn catalog_scale_for(width_css_px: u32) -> u32 {
if width_css_px <= CATALOG_SCALE_2X_MAX_CSS_PX {
2
} else {
1
}
}
/// `[ui] mermaid_routing`'s values, as the catalog's "What the settings change" section lists
/// them — **`konoma-orthogonal` first**, because that mode is what the page is about, and the
/// site leads with it everywhere else too.
const CATALOG_ROUTINGS: [&str; 2] = ["konoma-orthogonal", "splines"];
/// `[ui] mermaid_curve`'s 13 values, in the configuration reference's own order (the default
/// `"basis"` first, then the straight/right-angle family, the through-the-waypoints splines, the
/// non-overshooting pair, the bumps, and mermaid's own `"rounded"`).
const CATALOG_CURVES: [&str; 13] = [
"basis",
"linear",
"step",
"stepBefore",
"stepAfter",
"natural",
"cardinal",
"catmullRom",
"monotoneX",
"monotoneY",
"bumpX",
"bumpY",
"rounded",
];
/// `[ui] mermaid_theme`'s 5 values, default first — the configuration reference's own order.
const CATALOG_THEMES: [&str; 5] = ["dark", "light", "classic", "forest", "neutral"];
/// Terminal width the `[ui] mermaid = "text"` fallback is drawn at for the catalog. Wide enough
/// that neither sample has to wrap (wrapping is a property of the pane, not of the renderer, and
/// the page shows the drawing), narrow enough to stay a plausible pane.
const CATALOG_TEXT_COLUMNS: u16 = 100;
/// A flowchart's four `rankdir` keywords, in mermaid's own order. The catalog draws the sample
/// once per direction under `konoma-orthogonal` to show that the routing rules do not change with
/// it — `docs/FEATURE-MERMAID-RENDERER.md` §10's own design references `2b`/`2c` are the same
/// graph in LR and TB for exactly that reason.
const CATALOG_FLOW_DIRECTIONS: [&str; 4] = ["LR", "TB", "RL", "BT"];
/// A state diagram states its direction with a `direction` line inside the body rather than on the
/// header, and the absence of one means `TB` — so the catalog's pair is "as written" against "with
/// `direction LR` added".
const CATALOG_STATE_DIRECTIONS: [&str; 2] = ["TB", "LR"];
/// The sample's flowchart header with its direction keyword replaced.
///
/// Deliberately narrow: it keeps the header's own keyword (`flowchart` / `graph`) and replaces
/// everything after it, which is exactly right for a header of the shape `flowchart LR` and wrong
/// for anything more elaborate. The dump asserts the header really is that shape before calling
/// this, so a rewritten sample cannot silently produce a diagram nobody meant.
fn with_flow_direction(code: &str, direction: &str) -> String {
let mut lines = code.lines();
let head = lines.next().unwrap_or_default();
let keyword = head.split_whitespace().next().unwrap_or("flowchart");
let body: String = lines.map(|l| format!("\n{l}")).collect();
format!("{keyword} {direction}{body}")
}
/// The sample's state-diagram source with a `direction <dir>` line added just under the header —
/// or returned untouched for `"TB"`, which is what the absence of that line already means.
fn with_state_direction(code: &str, direction: &str) -> String {
if direction == "TB" {
return code.to_string();
}
let mut lines = code.lines();
let head = lines.next().unwrap_or_default();
let body: String = lines.map(|l| format!("\n{l}")).collect();
format!("{head}\n direction {direction}{body}")
}
/// The two ways a diagram overrides `[ui] mermaid_curve` from inside its own source, as the
/// catalog shows them: `(file stem, the line the sample gains, whether it goes on the front)`.
///
/// Both are drawn with the config left at its default `"basis"`, so the difference in the picture
/// is the diagram's own doing — which is the whole point of the block.
const CATALOG_OVERRIDES: [(&str, &str, bool); 2] = [
(
"init-step",
"%%{init: {\"flowchart\": {\"curve\": \"step\"}}}%%",
true,
),
// Edge **1**, not 0. `linkStyle` counts edges in declaration order, and the sample's edge 0
// (`K --> S`) is a straight horizontal run that draws the same under every curve — the SVG
// bytes would differ (the assertion would pass) while the picture on the page did not, which
// is the worst of both. Edge 1 (`S -->|Tree| M`) bends, so the override is visible.
(
"linkstyle-stepAfter",
" linkStyle 1 interpolate stepAfter",
false,
),
];
/// Applies one [`CATALOG_OVERRIDES`] entry to a source.
fn with_override(code: &str, line: &str, prepend: bool) -> String {
if prepend {
format!("{line}\n{code}")
} else {
format!("{code}\n{line}")
}
}
/// Renders one fence through the production path and writes it as a PNG at `dir/file`, returning
/// the device scale it chose ([`catalog_scale_for`]) so the caller can record it in the manifest.
///
/// Shared by the kind gallery and the settings gallery below so both are provably the *same*
/// path: [`crate::preview::markdown::mermaid_to_svg_flow`] is the exact function `App::media_load`
/// / `md_media` call for an inline ```mermaid fence. `what` is the caller's own label for the
/// panic messages, since neither gallery names a render the same way.
fn write_catalog_png(
dir: &FsPath,
file: &str,
code: &str,
theme: &str,
curve: &str,
routing: &str,
what: &str,
) -> u32 {
let svg = crate::preview::markdown::mermaid_to_svg_flow(code, theme, curve, routing)
.unwrap_or_else(|| panic!("{what}: must render under routing={routing}"));
let path = dir.join(file);
let (w, h) = crate::preview::svg::intrinsic_size_bytes(svg.as_bytes())
.unwrap_or_else(|| panic!("{what}: SVG must have a size"));
let scale = catalog_scale_for(w);
// `rasterize_bytes` takes a target for the *longest* side, so asking for `scale * max(w, h)`
// is exactly a `scale`× device-pixel-ratio raster. The background stays transparent, the same
// as in the terminal.
let img = crate::preview::svg::rasterize_bytes(svg.as_bytes(), &path, scale * w.max(h))
.unwrap_or_else(|| panic!("{what}: must rasterise"));
img.save(&path)
.unwrap_or_else(|e| panic!("{what}: write {path:?}: {e}"));
scale
}
/// Renders every fence of the two sample galleries for the documentation site's Mermaid catalog
/// page (`site/src/content/docs/guides/mermaid-catalog.mdx` and its `ja/` twin), writing 2×-scale
/// PNGs plus a `manifest.json` the page's Astro component is driven by.
///
/// **Production path, not a parallel renderer.** Each fence goes through
/// [`crate::preview::markdown::mermaid_to_svg_flow`] — the exact function `App::media_load` /
/// `md_media` call for an inline ```mermaid fence — with the shipped defaults `[ui]
/// mermaid_theme = "dark"` and `[ui] mermaid_curve = "basis"`. Only `routing` varies.
///
/// **Why only two kinds are drawn twice.** `mermaid_to_svg_reason_flow`'s dispatcher threads
/// `routing` into exactly two arms: `render_konoma_flow` (claimed by `flowchart_is_ours`) and
/// `render_konoma_state` (claimed by `state_is_ours`). Every other kind is routed through the
/// shared `Draw` table, whose signature is `fn(&str, &str) -> Result<String, RenderError>` — code
/// and theme only, so `[ui] mermaid_routing` is *structurally* unable to reach them. The
/// predicates below are the dispatcher's own, so this file cannot drift from that claim.
///
/// **The settings gallery.** Alongside the per-kind renders the dump also writes a `settings/<nn>/`
/// set per sample the settings reach — every flowchart fence under both `mermaid_routing` values,
/// all 13 `mermaid_curve` values and all 5 `mermaid_theme` values, and the state-diagram fence
/// under the 5 themes (it never reads a curve, and its routing pair is already in the kind gallery
/// above). Same production entry point, same 2× raster; only the argument under test moves, so a
/// difference between two pictures in that section can only have come from the setting the caption
/// names. That those values really do change the picture (and really are inert under
/// `konoma-orthogonal`) is asserted permanently by
/// [`catalog_settings_values_really_change_the_picture`], which is *not* `#[ignore]`d and runs over
/// these same sample sources — the dump writes pictures, the test states the claim the page makes
/// about them.
///
/// Stale files are removed first: an image nobody regenerated is worse than a missing one, because
/// the page would keep shipping it. Removing the language directory takes `settings/` with it.
///
/// `#[ignore]`d like [`orthogonal_design_reference_dump`] — run explicitly:
/// `cargo test -- --ignored site_mermaid_catalog_dump`.
#[test]
#[ignore = "writes PNG files for the docs site: cargo test -- --ignored site_mermaid_catalog_dump"]
fn site_mermaid_catalog_dump() {
for (lang, sample) in [
("en", "samples/mermaid.md"),
("ja", "samples/mermaid.ja.md"),
] {
let md = std::fs::read_to_string(sample)
.unwrap_or_else(|e| panic!("{lang}: read {sample}: {e}"));
let fences = mermaid_fences_of(&md);
assert!(
!fences.is_empty(),
"{lang}: {sample} must contain ```mermaid fences"
);
let dir = std::path::Path::new("site/src/assets/mermaid-catalog").join(lang);
// Delete first: a renamed or dropped fence must not leave an orphan PNG behind.
if dir.exists() {
std::fs::remove_dir_all(&dir).unwrap_or_else(|e| panic!("{lang}: clear {dir:?}: {e}"));
}
std::fs::create_dir_all(&dir).unwrap_or_else(|e| panic!("{lang}: create {dir:?}: {e}"));
let mut items = Vec::new();
for (i, code) in fences.iter().enumerate() {
let order = i + 1;
let kind = crate::preview::mermaid::chart::first_word(code);
// The dispatcher's own predicates (see this test's doc comment).
let takes_routing = crate::preview::mermaid::flowchart::is_flowchart(code)
|| crate::preview::mermaid::state::is_state_diagram(code);
let variants: &[(&str, &str)] = if takes_routing {
// Orthogonal first: the catalog page leads with konoma's own routing.
&[("orthogonal", "konoma-orthogonal"), ("splines", "splines")]
} else {
&[("default", "splines")]
};
let mut renders = Vec::new();
for (variant, routing) in variants {
let file = format!("{order:02}-{kind}-{variant}.png");
let scale = write_catalog_png(
&dir,
&file,
code,
"dark",
"basis",
routing,
&format!("{lang} #{order} ({kind})"),
);
renders.push(serde_json::json!({
"variant": variant,
"routing": routing,
"file": file,
"scale": scale,
}));
}
items.push(serde_json::json!({
"order": order,
"kind": kind,
"orthogonal": takes_routing,
"renders": renders,
"source": code,
}));
}
// ----- settings gallery: every sample a setting reaches, under every value of it -----
//
// One block per fence, written under `settings/<nn>/` so the file names stay the same from
// sample to sample — `settings[i]` and `items[i]` are the same fence, which is what lets
// the kind gallery hang a theme strip under a render. Which options a sample gets is the
// dispatcher's claim again, not a hand-kept list:
//
// - a **flowchart** reads all three, so it gets `routing` ×2, `curve` ×13, `theme` ×5;
// - a **state diagram** reads `routing` (already drawn as the pair in the kind gallery
// above) but never `curve`, so it gets `theme` ×5;
// - **every other kind** is routed through the shared `Draw` table, whose signature is
// `fn(&str, &str)` — code and theme. `routing` and `curve` are structurally unable to
// reach it, but `theme` reaches *all* of them, so every kind gets its `theme` ×5 too.
//
// All three samples rather than only the smallest one, because a setting shows itself on a
// different sample: `theme` is legible against author-set `classDef` colours (02), and
// `curve` only really separates on the long rank-spanning edges of the busy one (03).
let settings_root = dir.join("settings");
std::fs::create_dir_all(&settings_root)
.unwrap_or_else(|e| panic!("{lang}: create {settings_root:?}: {e}"));
let mut settings = Vec::new();
for (i, code) in fences.iter().enumerate() {
let order = i + 1;
let is_flow = crate::preview::mermaid::flowchart::is_flowchart(code);
let is_state = crate::preview::mermaid::state::is_state_diagram(code);
let kind = crate::preview::mermaid::chart::first_word(code);
let dir_of = settings_root.join(format!("{order:02}"));
std::fs::create_dir_all(&dir_of)
.unwrap_or_else(|e| panic!("{lang}: create {dir_of:?}: {e}"));
// One closure per option would repeat the same three lines; this one takes the
// file-name prefix and the three arguments, and the caller varies exactly one of them.
let shot = |prefix: &str, value: &str, theme: &str, curve: &str, routing: &str| {
let file = format!("{prefix}-{value}.png");
let scale = write_catalog_png(
&dir_of,
&file,
code,
theme,
curve,
routing,
&format!("{lang} settings {order:02} {prefix}={value}"),
);
serde_json::json!({
"value": value,
"file": format!("settings/{order:02}/{file}"),
"scale": scale,
})
};
let mut block = serde_json::Map::new();
block.insert("order".into(), serde_json::json!(order));
block.insert("kind".into(), serde_json::json!(kind));
// A language-neutral identifier, not display text: the page writes its own headings,
// in its own language. This is what an alt string and a debug message name.
block.insert(
"label".into(),
serde_json::json!(format!("{order:02}-{kind}")),
);
block.insert("source".into(), serde_json::json!(code));
// A variant of the *source* rather than of an argument: same three writes, but the
// caption is what was edited into the diagram, not a config value.
let shot_src = |prefix: &str, value: &str, src: &str, routing: &str| {
let file = format!("{prefix}-{value}.png");
let scale = write_catalog_png(
&dir_of,
&file,
src,
"dark",
"basis",
routing,
&format!("{lang} settings {order:02} {prefix}={value}"),
);
serde_json::json!({
"value": value,
"file": format!("settings/{order:02}/{file}"),
"scale": scale,
})
};
if is_flow {
// `curve` is passed as the shipped default for the routing pair and is genuinely
// irrelevant under `konoma-orthogonal` (there is no curve, only right-angle
// segments) — the permanent test below states that as an assertion rather than
// leaving it as a claim in a comment.
let routings: Vec<_> = CATALOG_ROUTINGS
.iter()
.map(|r| shot("routing", r, "dark", "basis", r))
.collect();
let curves: Vec<_> = CATALOG_CURVES
.iter()
.map(|c| shot("curve", c, "dark", c, "splines"))
.collect();
block.insert(
"routing".into(),
serde_json::json!({ "default": "splines", "values": routings }),
);
block.insert(
"curve".into(),
serde_json::json!({ "default": "basis", "values": curves }),
);
}
// Both a flowchart `direction` block and the per-diagram overrides go on the *first*
// flowchart only: each is one point (routing is direction-agnostic; a diagram can
// override the curve from inside its own source), and repeating either on every sample
// would multiply the page's download for nothing.
if is_flow && order == 1 {
// konoma-orthogonal's post-dagre passes used to key on the flow *axis* without its
// *sign*, so `RL` rendered byte-identical to `LR` and `BT` to `TB` — fixed by the
// mirror rule `super::canonicalise_flow_axis` / `super::mirror_flow_axis` names
// (`orthogonal_rl_is_the_exact_mirror_of_lr` / `orthogonal_bt_is_the_exact_mirror_
// of_tb` pin it permanently), so all four directions are genuinely four pictures now.
let directions: Vec<_> = CATALOG_FLOW_DIRECTIONS
.iter()
.map(|d| {
shot_src(
"direction",
d,
&with_flow_direction(code, d),
"konoma-orthogonal",
)
})
.collect();
block.insert(
"direction".into(),
serde_json::json!({ "default": "LR", "values": directions }),
);
let overrides: Vec<_> = CATALOG_OVERRIDES
.iter()
.map(|(stem, line, prepend)| {
let mut v = shot_src(
"override",
stem,
&with_override(code, line, *prepend),
"splines",
);
// The exact line the reader would add, shown next to the picture: the
// block is about precedence, and precedence is a property of that line.
v["line"] = serde_json::json!(line.trim());
v
})
.collect();
block.insert(
"override".into(),
serde_json::json!({ "default": "basis", "values": overrides }),
);
}
if is_state {
let directions: Vec<_> = CATALOG_STATE_DIRECTIONS
.iter()
.map(|d| {
shot_src(
"direction",
d,
&with_state_direction(code, d),
"konoma-orthogonal",
)
})
.collect();
block.insert(
"direction".into(),
serde_json::json!({ "default": "TB", "values": directions }),
);
}
// `theme` is drawn under `"splines"` for every sample, state diagram included: it is
// inert under `konoma-orthogonal`, so five identical pictures is the only other thing
// this loop could produce.
let themes: Vec<_> = CATALOG_THEMES
.iter()
.map(|t| shot("theme", t, t, "basis", "splines"))
.collect();
block.insert(
"theme".into(),
serde_json::json!({ "default": "dark", "values": themes }),
);
// Which blocks this sample got, in the order the page renders them: the routing rules,
// then those rules under each direction, then the shape of the line, then the two ways
// a diagram overrides that shape itself, then the colours.
let options: Vec<&str> = ["routing", "direction", "curve", "override", "theme"]
.into_iter()
.filter(|k| block.contains_key(*k))
.collect();
block.insert("options".into(), serde_json::json!(options));
settings.push(serde_json::Value::Object(block));
}
// The kind gallery hangs each kind's theme strip off `settings[i]` while drawing
// `items[i]`, so the two lists must stay index-for-index the same fences.
assert_eq!(
settings.len(),
items.len(),
"{lang}: every fence needs a settings block — the page pairs them by index"
);
// ----- `[ui] mermaid = "text"`: the Unicode box-drawing fallback, as text -----
//
// Written as `.txt` rather than as a picture, because text is literally what the terminal
// puts on the screen in that mode — a screenshot of it would be a picture of characters.
// The entry point is [`crate::preview::markdown::render_mermaid_file`], what a standalone
// `.mmd` file goes through; its `Line`s carry no styling on this path (each is built from
// one owned `String`), so joining the spans back gives exactly the drawn text.
//
// Two fences: the first flowchart, and the sequence diagram — the two shapes the fallback
// handles most differently (boxes and arrows vs. lifelines, activation bars and an `alt`).
let text_dir = dir.join("text");
std::fs::create_dir_all(&text_dir)
.unwrap_or_else(|e| panic!("{lang}: create {text_dir:?}: {e}"));
let mut texts = Vec::new();
for (i, code) in fences.iter().enumerate() {
let order = i + 1;
let kind = crate::preview::mermaid::chart::first_word(code);
if order != 1 && kind != "sequenceDiagram" {
continue;
}
let drawn: Vec<String> =
crate::preview::markdown::render_mermaid_file(code, CATALOG_TEXT_COLUMNS)
.iter()
.map(|l| l.spans.iter().map(|s| s.content.as_ref()).collect())
.collect();
assert!(
drawn.len() > 3,
"{lang} #{order} ({kind}): the text fallback must actually draw something, got \
{drawn:?}"
);
let file = format!("{order:02}-{kind}.txt");
let path = text_dir.join(&file);
std::fs::write(&path, format!("{}\n", drawn.join("\n")))
.unwrap_or_else(|e| panic!("{lang}: write {path:?}: {e}"));
texts.push(serde_json::json!({
"order": order,
"kind": kind,
"file": format!("text/{file}"),
}));
}
assert_eq!(
texts.len(),
2,
"{lang}: the text block needs the first flowchart and the sequence diagram"
);
let manifest = serde_json::json!({
"lang": lang,
"sample": sample,
"theme": "dark",
"curve": "basis",
// The device scale is **per image** (each render's own `scale` field): a diagram wide
// enough that the page shrinks it is rastered at 1×. This records only the rule.
"scale_2x_max_css_px": CATALOG_SCALE_2X_MAX_CSS_PX,
"items": items,
// Sample order, and within a sample each option's values in the order above — the page
// renders both lists as it finds them, so this order is the order a reader sees:
// konoma-orthogonal first, then each option's own default.
"settings": settings,
"text": { "columns": CATALOG_TEXT_COLUMNS, "items": texts },
});
let mut text = serde_json::to_string_pretty(&manifest).expect("serialise manifest");
text.push('\n');
let path = dir.join("manifest.json");
std::fs::write(&path, text).unwrap_or_else(|e| panic!("{lang}: write {path:?}: {e}"));
}
}
/// One sample's worth of the claim [`catalog_settings_values_really_change_the_picture`] makes.
///
/// Goes through [`crate::preview::markdown::mermaid_to_svg_flow`] — the dispatcher the dump and
/// production both call — rather than [`render_flow`], because this runs over state-diagram
/// sources too and the flowchart entry point cannot draw one.
///
/// `reads_curve` and `reads_routing` are the dispatcher's own divisions, not per-sample opinions:
///
/// * only a **flowchart**'s edges read `[ui] mermaid_curve`, so anything else would draw 13
/// identical pictures and "pairwise different" would be a false claim rather than a failing one;
/// * only a flowchart and a **state diagram** read `[ui] mermaid_routing`. Every other kind goes
/// through the shared `Draw` table (`fn(&str, &str)` — code and theme), which routing cannot
/// reach, so "the theme is inert under konoma-orthogonal" is not true of them: with no orthogonal
/// palette in play the theme still paints, exactly as it does under `"splines"`.
///
/// `theme` is checked for **every** sample, because it reaches every kind.
fn assert_catalog_settings_change_one_sample(
name: &str,
code: &str,
reads_curve: bool,
reads_routing: bool,
) {
let render = |theme: &str, curve: &str, routing: &str| {
crate::preview::markdown::mermaid_to_svg_flow(code, theme, curve, routing).unwrap_or_else(
|| panic!("{name}: must render (theme={theme} curve={curve} routing={routing})"),
)
};
if reads_curve {
let curves: Vec<(&str, String)> = CATALOG_CURVES
.iter()
.map(|c| (*c, render("dark", c, "splines")))
.collect();
for i in 0..curves.len() {
for j in (i + 1)..curves.len() {
assert_ne!(
curves[i].1, curves[j].1,
"{name}: mermaid_curve {} and {} must draw differently — the catalog shows \
them as two pictures",
curves[i].0, curves[j].0
);
}
}
}
let themes: Vec<(&str, String)> = CATALOG_THEMES
.iter()
.map(|t| (*t, render(t, "basis", "splines")))
.collect();
for i in 0..themes.len() {
for j in (i + 1)..themes.len() {
assert_ne!(
themes[i].1, themes[j].1,
"{name}: mermaid_theme {} and {} must draw differently — the catalog shows them \
as two pictures",
themes[i].0, themes[j].0
);
}
}
if !reads_routing {
return;
}
let baseline = render("dark", "basis", "konoma-orthogonal");
if reads_curve {
for curve in CATALOG_CURVES {
assert_eq!(
render("dark", curve, "konoma-orthogonal"),
baseline,
"{name}: mermaid_curve {curve} must be inert under konoma-orthogonal — the page \
says so"
);
}
}
for theme in CATALOG_THEMES {
assert_eq!(
render(theme, "basis", "konoma-orthogonal"),
baseline,
"{name}: mermaid_theme {theme} must be inert under konoma-orthogonal — the page says so"
);
}
}
/// The catalog page's "What the settings change" section shows 65 pictures and claims each one
/// inside a grid is a *different* look. This states that claim as an assertion, permanently — the
/// dump above is `#[ignore]`d, so nothing there ever runs in CI, and a change that quietly
/// collapsed two curves (or made `mermaid_theme` inert under `splines`) would leave the page
/// shipping grids of identical pictures with different captions under them.
///
/// Three claims, one per sub-block of that section:
///
/// 1. All 13 `mermaid_curve` values draw a **pairwise different** SVG. Stronger than
/// `different_curves_draw_different_svg_path_data` (three of them) and than
/// `the_eight_new_curves_draw_different_paths_from_each_other` (eight, and at the free-function
/// level rather than through the dispatcher), and stated over exactly [`CATALOG_CURVES`] — the
/// same list the page's grid is built from, so the two cannot drift apart.
/// 2. All 5 `mermaid_theme` values draw a pairwise different SVG.
/// 3. Under `"konoma-orthogonal"`, changing either produces a **byte-identical** SVG. That is the
/// sentence both language versions of the page print ("ignored under konoma-orthogonal"), and
/// it is the converse of 1 and 2: an assertion that only says "these differ" would still pass
/// if the orthogonal mode had started reading the curve.
///
/// **Stated over the sources the page actually ships**, not only a lab specimen. The tiny inline
/// flowchart comes first and says what it needs on its own line — `A --> D` spans three ranks,
/// which is what gives dagre the intermediate waypoints a curve can differ *on* (on a straight
/// two-point edge several of these 13 agree, and `different_curves_draw_different_svg_path_data`'s
/// own doc records that trap being hit for real). Then every fence of `samples/mermaid.md` that
/// the dump writes a settings block for goes through the same three claims, so the assertion covers
/// the busy `03` diagram whose long rank-spanning edges are what actually separate the curves on
/// the page, the `02` diagram whose author-set `classDef` colours the themes have to survive, and
/// the state diagram (themes only). The sample is read through `CARGO_MANIFEST_DIR` so the test
/// does not depend on the working directory a runner happens to use.
#[test]
fn catalog_settings_values_really_change_the_picture() {
if !text_metrics::fonts_available() {
return;
}
assert_catalog_settings_change_one_sample(
"inline three-rank flowchart",
"flowchart TD\n A[Tree] --> B{Kind}\n B --> C[Image]\n C --> D[Draw]\n A --> D",
true,
true,
);
let sample = FsPath::new(env!("CARGO_MANIFEST_DIR")).join("samples/mermaid.md");
let md = std::fs::read_to_string(&sample).unwrap_or_else(|e| panic!("read {sample:?}: {e}"));
// **Every** fence, not only the ones a routing or a curve reaches: `mermaid_theme` is passed
// to all 23 kinds, so the catalog now hangs a theme strip under every render in the kind
// gallery, and this is the assertion that those strips are five pictures rather than five
// copies.
let mut covered = 0;
for (i, code) in mermaid_fences_of(&md).iter().enumerate() {
let is_flow = crate::preview::mermaid::flowchart::is_flowchart(code);
let is_state = crate::preview::mermaid::state::is_state_diagram(code);
assert_catalog_settings_change_one_sample(
&format!("samples/mermaid.md fence #{:02}", i + 1),
code,
is_flow,
is_flow || is_state,
);
covered += 1;
}
// The loop must actually have run over every sample the gallery draws — a scanner that
// silently found nothing would leave every assertion above un-evaluated and still pass.
assert!(
covered >= 23,
"samples/mermaid.md must still hold one fence per Mermaid kind the catalog draws: found \
{covered}"
);
}
/// Every direction the catalog's "Direction" block draws still obeys the orthogonal rules, and the
/// picture matches what the page's own sentence claims: `RL` is the exact mirror of `LR`, `BT` is
/// the exact mirror of `TB`, and `LR` genuinely differs from `TB` — turning the flow axis is the
/// half of `rankdir` the orthogonal path reads.
///
/// Stated with the very helpers the general corpus uses rather than a private re-derivation:
/// [`check_only_axis_parallel_segments`] (also used by
/// `orthogonal_routing_draws_only_axis_parallel_segments`) for the axis-parallel claim, and
/// [`assert_mirrored_diagrams`] — the same mirror check [`orthogonal_rl_is_the_exact_mirror_of_lr`]
/// and [`orthogonal_bt_is_the_exact_mirror_of_tb`] state over the general corpus — for the mirror
/// claim. `orthogonal_corpus` and that corpus already carry all four directions, but on *their own*
/// sources; this pins the same claims on the source the page actually prints them under.
#[test]
fn catalog_direction_renders_obey_the_orthogonal_rules() {
if !text_metrics::fonts_available() {
return;
}
let sample = FsPath::new(env!("CARGO_MANIFEST_DIR")).join("samples/mermaid.md");
let md = std::fs::read_to_string(&sample).unwrap_or_else(|e| panic!("read {sample:?}: {e}"));
let fences = mermaid_fences_of(&md);
let code = fences
.first()
.expect("samples/mermaid.md must still open with a fence");
assert!(
crate::preview::mermaid::flowchart::is_flowchart(code),
"the direction block is built on the first fence, which must still be a flowchart"
);
// `CATALOG_FLOW_DIRECTIONS` is `["LR", "TB", "RL", "BT"]` — the catalog's own printed order —
// so index 0/2 is the LR/RL pair and 1/3 is the TB/BT pair.
let mut laid_out: Vec<(&str, Diagram)> = Vec::new();
let mut drawn: Vec<(&str, String)> = Vec::new();
for direction in CATALOG_FLOW_DIRECTIONS {
let src = with_flow_direction(code, direction);
let diagram = laid_out_flow(&src, "basis", "konoma-orthogonal");
check_only_axis_parallel_segments(&format!("catalog direction {direction}"), &diagram);
let svg = crate::preview::markdown::mermaid_to_svg_flow(
&src,
"dark",
"basis",
"konoma-orthogonal",
)
.unwrap_or_else(|| panic!("direction={direction}: must render"));
laid_out.push((direction, diagram));
drawn.push((direction, svg));
}
// LR turns the flow axis relative to TB, which is the half of `rankdir` the orthogonal path
// does read — the two are genuinely different pictures.
assert_ne!(
drawn[0].1, drawn[1].1,
"LR and TB must draw differently under konoma-orthogonal"
);
// The reversal itself: `RL` is `LR` reflected along the flow axis, and `BT` is `TB` reflected —
// the exact sentence the page prints under the grid.
assert_mirrored_diagrams(
"catalog direction LR/RL",
&laid_out[0].1,
&laid_out[2].1,
false,
);
assert_mirrored_diagrams(
"catalog direction TB/BT",
&laid_out[1].1,
&laid_out[3].1,
true,
);
// The state diagram's own half: `direction LR` must move it off the default TB.
let state = fences
.iter()
.find(|c| crate::preview::mermaid::state::is_state_diagram(c))
.expect("samples/mermaid.md must still hold a state diagram");
let by_dir: Vec<(&str, String)> = CATALOG_STATE_DIRECTIONS
.iter()
.map(|d| {
let src = with_state_direction(state, d);
let svg = crate::preview::markdown::mermaid_to_svg_flow(
&src,
"dark",
"basis",
"konoma-orthogonal",
)
.unwrap_or_else(|| panic!("state direction={d}: must render"));
(*d, svg)
})
.collect();
assert_ne!(
by_dir[0].1, by_dir[1].1,
"a state diagram's `direction LR` must draw differently from the default TB"
);
}
/// The catalog's "Overrides written in the diagram" block claims two things that are easy to write
/// and easy to get wrong: that a `%%{init}%%` directive and a `linkStyle ... interpolate` really
/// do beat the config default (`"basis"` here, untouched), and that both are ignored under
/// `konoma-orthogonal` — the same precedence sentence the configuration reference prints.
///
/// Stated on the exact source the page shows, with the exact lines it shows being added, so the
/// captions and the pictures cannot drift apart from what actually happens.
#[test]
fn catalog_override_block_beats_the_default_curve_and_is_inert_under_orthogonal() {
if !text_metrics::fonts_available() {
return;
}
let sample = FsPath::new(env!("CARGO_MANIFEST_DIR")).join("samples/mermaid.md");
let md = std::fs::read_to_string(&sample).unwrap_or_else(|e| panic!("read {sample:?}: {e}"));
let code = mermaid_fences_of(&md)
.first()
.expect("samples/mermaid.md must still open with a fence")
.clone();
let plain = crate::preview::markdown::mermaid_to_svg_flow(&code, "dark", "basis", "splines")
.expect("the plain sample must render");
let orthogonal =
crate::preview::markdown::mermaid_to_svg_flow(&code, "dark", "basis", "konoma-orthogonal")
.expect("the plain sample must render under konoma-orthogonal");
for (stem, line, prepend) in CATALOG_OVERRIDES {
let src = with_override(&code, line, prepend);
let splines =
crate::preview::markdown::mermaid_to_svg_flow(&src, "dark", "basis", "splines")
.unwrap_or_else(|| panic!("{stem}: must render"));
assert_ne!(
splines,
plain,
"{stem}: `{}` must beat the default mermaid_curve = \"basis\" — the catalog shows it \
as a different picture",
line.trim()
);
let ortho = crate::preview::markdown::mermaid_to_svg_flow(
&src,
"dark",
"basis",
"konoma-orthogonal",
)
.unwrap_or_else(|| panic!("{stem}: must render under konoma-orthogonal"));
assert_eq!(
ortho,
orthogonal,
"{stem}: `{}` must be inert under konoma-orthogonal — the page says so",
line.trim()
);
}
}
/// Finding 1 (high): the cluster invariants stage 1b already states over `CORPUS` under
/// `"splines"` (`check_clusters_hold_their_members` and its three siblings, `pub(super)` above so
/// this section can reuse them rather than re-deriving the same geometry questions), run again
/// under `"konoma-orthogonal"` — routing an edge does not move a node or a frame, but §10-1 item 1's
/// own eviction growth *does* (a face too narrow for its ports grows the node, and `lay_out_spec`
/// re-lays the whole diagram out from the grown size), so nothing before this audit had actually
/// checked a frame still holds its members once that growth has happened.
///
/// The design-reference sources were **not** in this list until §10-5 round 4, and that gap cost a
/// real bug: `zz-design-2b`'s own `解析サンドボックス` (a member of `クラウド` that
/// `clear_foreign_cluster_overlaps` pushed clear of its sibling frame `保存層`) ended up outside its
/// own frame, and every test stayed green — the state-diagram sibling of this test
/// (`state_tests::orthogonal_state_nodes_and_clusters_stay_correct_after_growth`) had been running
/// its own half of the design corpus all along, so only the flowchart half was blind.
#[test]
fn invariant_orthogonal_clusters_hold_their_members() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let tree = tree_of_src(src);
check_clusters_hold_their_members(name, &d, &tree);
}
}
/// §10-5 part-3 item 1's own converse of the check just above — run over the same corpus, plus the
/// permanent design-reference sources (§10-5's own "恒久テスト対象" instruction), since `zz-
/// design-4a`'s state-diagram sibling was the case that actually exposed the gap this pins for the
/// flowchart side of the shared `orthogonal.rs` machinery too.
#[test]
fn invariant_orthogonal_foreign_nodes_stay_out_of_clusters() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let tree = tree_of_src(src);
check_foreign_nodes_stay_out_of_clusters(name, &d, &tree);
}
}
#[test]
fn invariant_orthogonal_nested_clusters_sit_inside_their_parent() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
check_nested_clusters_sit_inside_their_parent(
name,
&laid_out_flow(src, "basis", "konoma-orthogonal"),
);
}
}
#[test]
fn invariant_orthogonal_unrelated_clusters_do_not_overlap() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
check_unrelated_clusters_do_not_overlap(
name,
&laid_out_flow(src, "basis", "konoma-orthogonal"),
);
}
}
#[test]
fn invariant_orthogonal_cluster_titles_stay_inside_their_frame_and_off_every_node() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain(orthogonal_design_reference_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let tree = tree_of_src(src);
check_cluster_titles(name, &d, &tree);
}
}
/// Finding 1's own eviction-growth half, stated directly rather than only through the invariants
/// above: `orthogonal-subgraph-growth`'s `T` must actually grow past its label-only size (the
/// scenario those invariants are being run *for*), and its grown box must still fit inside its own
/// frame with the ordinary 16px cluster padding — not merely "the invariant above happened to pass
/// for unrelated reasons".
///
/// §10-3 item 3's own correction (`classify`'s `merge_target_side` doc) moved this fixture's five
/// merges (`W1`..`W5 --> T`) off `T`'s cross-axis face (Left/Right, for this `TD` diagram — a
/// height requirement) onto its flow-axis Top face instead (a WIDTH requirement) — the same axis
/// flip `orthogonal_growth_widens_a_node_whose_face_cannot_fit_its_ports`'s own doc explains for
/// its very similar `Z` fixture. Dumped and confirmed by hand, not assumed.
#[test]
fn orthogonal_eviction_growth_inside_a_subgraph_still_fits_the_frame() {
if !text_metrics::fonts_available() {
return;
}
let src = orthogonal_only_corpus()
.into_iter()
.find(|(name, _)| *name == "orthogonal-subgraph-growth")
.unwrap()
.1;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let t = d.node("T").expect("T must exist");
// §10-8 N4's own label-derived half, since 2026-09-05 — `shapes::size(Flow(Rect), …)` before
// that. The rule this test pins is "the ports grew it, and only along their own axis", which
// is a statement about the *difference* from the label-derived box, so it is stated against
// whatever that box currently is rather than against the numbers it once produced.
let label_only = shapes::orthogonal_label_box(t.shape, &t.label);
assert!(
t.size.w > label_only.w + 1.0,
"T must actually grow past its label-only width to fit its five merge ports on its Top \
face: grown={} label_only={}",
t.size.w,
label_only.w
);
assert!(
(t.size.h - label_only.h).abs() < 1e-6,
"T's height must be untouched — nothing asked its Left/Right faces to grow any more: \
grown={} label_only={}",
t.size.h,
label_only.h
);
let cluster = d.cluster("one").expect("cluster one must exist");
let out = escapes(t.bounds(), cluster.bounds());
assert!(
out <= 0.01,
"T's grown box must still sit fully inside its own frame: pokes {out:.2}px out"
);
}
/// Finding 2 (high): a `classDef`/`style`-painted decision node under `"konoma-orthogonal"` draws
/// as a chamfered rectangle (`decision_node_is_chamfered_under_orthogonal_and_a_diamond_under_splines`
/// already pins the shape), but nothing before this audit ever rendered one *with* a resolved paint
/// — every existing orthogonal SVG test uses an unstyled node, and `CORPUS`'s own
/// `classdef-and-style-cascade` source (which does exercise the cascade) has no decision node.
/// `svg::emit_node`'s own `fill`/`stroke`/`sw` locals feed every `Outline` arm identically
/// (`Outline::Polygon` included, `svg.rs` line ~543), so this is really checking that a chamfered
/// node was not accidentally left on some *other* code path — the v0.28.0 regression's own shape
/// ("parses but nobody reads it").
#[test]
fn orthogonal_classdef_paints_a_chamfered_decision_node() {
let src =
"flowchart TD\n classDef hot fill:#f9f,stroke:#a00\n A --> B{cond}:::hot\n B --> C";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let b = d.node("B").expect("B must exist");
assert_eq!(
b.shape,
Glyph::ChamferedRect,
"B must chamfer under orthogonal routing"
);
let style = b
.style
.as_ref()
.expect("B must carry the resolved `:::hot` paint");
assert_eq!(style.fill.as_deref(), Some("#f9f"));
assert_eq!(style.stroke.as_deref(), Some("#a00"));
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
// `<polygon` also draws every arrowhead (a small 3-point triangle in the theme's own
// arrowhead colour) — pick the *node's* polygon by its 8 vertices, `shapes::polygon`'s own
// `Glyph::ChamferedRect` shape (already pinned by
// `decision_node_is_chamfered_under_orthogonal_and_a_diamond_under_splines`), not the first
// `<polygon` line in source order.
let vertex_count = |l: &str| -> usize {
l.split("points=\"")
.nth(1)
.and_then(|rest| rest.split('"').next())
.map(|pts| pts.split_whitespace().count())
.unwrap_or(0)
};
let polygon = svg
.lines()
.filter(|l| l.starts_with("<polygon"))
.find(|l| vertex_count(l) == 8)
.unwrap_or_else(|| panic!("no 8-vertex chamfered-rect <polygon> element in:\n{svg}"));
assert!(
polygon.contains("fill=\"#f9f\""),
"the chamfered node's own polygon must carry the classDef fill: {polygon}"
);
assert!(
polygon.contains("stroke=\"#a00\""),
"the chamfered node's own polygon must carry the classDef stroke: {polygon}"
);
}
// -------------------------------------------------------------------------------------------
// §10-3 item 6: an edge with no colour of its own takes a lightened version of the downstream
// (target) node's own resolved class colour, under `konoma-orthogonal` only
// -------------------------------------------------------------------------------------------
/// The plain, no-conflict case: `B` carries `:::hot` (`stroke:#1f6feb`, one of the three colours
/// `style::lighten`'s own reference set pins), `A->B` names neither `class` nor `linkStyle` of its
/// own, so it takes `style::lighten("#1f6feb")` — the exact value `style::tests::
/// lighten_approximates_the_three_reference_conversions_within_its_documented_error` already pins
/// for that input, reused here rather than re-derived so the two tests can never silently drift
/// apart about what `lighten` actually returns.
#[test]
fn orthogonal_edge_color_lightens_the_downstream_class_color() {
let src = "flowchart LR\n classDef hot stroke:#1f6feb\n A --> B:::hot";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let ab = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "B")
.expect("A->B must exist");
let style = ab
.style
.as_ref()
.expect("A->B must carry a derived style once B resolves a class stroke");
assert_eq!(
style.stroke.as_deref(),
Some("#508eef"),
"must match style::lighten(\"#1f6feb\") exactly"
);
// The label colour follows the line's own, same as the arrowhead already does via
// `tip_matches_line` — `emit_edge`'s own doc on that field, extended to the label by this
// rule.
assert_eq!(style.text.as_deref(), Some("#508eef"));
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
assert!(
svg.contains("stroke=\"#508eef\""),
"the edge's own <path> must draw in the lightened colour:\n{svg}"
);
assert!(
svg.contains("fill=\"#508eef\""),
"the arrowhead (tip_matches_line) must draw in the same lightened colour:\n{svg}"
);
}
/// Same rule, with a labelled edge: the label's own `<text>` must also carry the lightened colour
/// (`svg::emit_edge`'s `label_color`, wired from `edge.style.text` — previously never read for an
/// edge label at all, `theme.edge_label_text` hardcoded regardless of any `class`/`:::`/
/// `linkStyle` `color:` the source declared).
#[test]
fn orthogonal_edge_color_reaches_the_label_text_too() {
let src = "flowchart LR\n classDef hot stroke:#1f6feb\n A -->|hi| B:::hot";
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("must render");
assert!(
svg.contains("fill=\"#508eef\">") && svg.contains("hi"),
"the edge label's own <text> must draw in the lightened colour:\n{svg}"
);
}
/// An edge's own explicit paint — `linkStyle`, `class`, `:::`, or `style` naming *the edge itself*
/// — is the most specific instruction the source gave, and must win over the automatically
/// derived colour, exactly the priority order `docs/FEATURE-MERMAID-RENDERER.md` §10-3 item 6
/// states ("linkStyle 明示 > 自動導出 > テーマ既定"): a lightened downstream colour is a fallback
/// for an edge that asked for nothing, not an override for one that did.
#[test]
fn orthogonal_edge_color_prefers_an_explicit_link_style_over_the_derived_one() {
let src = "flowchart LR\n classDef hot stroke:#1f6feb\n A --> B:::hot\n linkStyle 0 stroke:#00ff00";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let ab = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "B")
.expect("A->B must exist");
assert_eq!(
ab.style.as_ref().and_then(|s| s.stroke.as_deref()),
Some("#00ff00"),
"the edge's own linkStyle must win over B's lightened class colour"
);
}
/// A downstream node with no resolved class colour at all leaves the edge exactly as it drew
/// before this rule existed: `[ui] mermaid_routing = "konoma-orthogonal"`'s own theme default
/// (`docs/FEATURE-MERMAID-RENDERER.md` §10-3 item 6's own "クラス無しの下流は従来のテーマ辺色").
#[test]
fn orthogonal_edge_color_leaves_an_unclassed_downstream_node_alone() {
let src = "flowchart LR\n A --> B";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let ab = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "B")
.expect("A->B must exist");
assert!(
ab.style.is_none(),
"an edge whose downstream node has no class must draw with no override at all: {:?}",
ab.style
);
}
/// §10-3 item 6 is `konoma-orthogonal` only ("konoma-orthogonal のみ", the rule's own opening
/// words) — the default `"splines"` routing must draw byte-for-byte what it always drew, the same
/// "既定は1バイトも変えない" invariant every other round-3 rule keeps.
#[test]
fn splines_routing_never_derives_an_edge_color_from_the_downstream_node() {
let src = "flowchart LR\n classDef hot stroke:#1f6feb\n A --> B:::hot";
let d = laid_out_flow(src, "basis", "splines");
let ab = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "B")
.expect("A->B must exist");
assert!(
ab.style.is_none(),
"splines routing must never derive an edge colour from the target node: {:?}",
ab.style
);
}
// Finding 3's app-wiring pin lives in `e2e_tests.rs`
// (`e2e_ui_mermaid_routing_changes_rendered_pixels_standalone_mmd_fullscreen` and
// `..._mermaid_fence_fullscreen`) — the other two ways a flowchart's pixels reach the screen
// besides an inline fence, which is all `e2e_ui_mermaid_routing_changes_rendered_pixels` covers.
/// Finding 5 (medium): §10-1 item 4's 2026-09-01 clarification — a back edge's line style is
/// whatever the author wrote (`-->`/`-.->`/`==>`), never something `konoma-orthogonal` itself
/// decides — pinned directly against the emitted SVG's `stroke-dasharray`, the one place a reader
/// actually sees it. `strokes` (`CORPUS`) exercises every stroke spelling but not a *back* edge in
/// particular; these two sources are minimal 2-node cycles so the back edge is the only edge in the
/// diagram whose stroke matters.
#[test]
fn orthogonal_back_edge_keeps_the_authors_own_line_style() {
// A solid back edge (the ordinary `-->`) must draw with no dash array at all.
let solid = render_flow(
"flowchart TD\n A --> B\n B --> A",
"dark",
"basis",
"konoma-orthogonal",
)
.expect("must render");
assert!(
!solid.contains("stroke-dasharray"),
"a solid back edge must not be drawn dashed just because it is routed on the perimeter \
lane: {solid}"
);
// A dotted back edge (`-.->`) must keep its own dashes.
let dotted = render_flow(
"flowchart TD\n A --> B\n B -.-> A",
"dark",
"basis",
"konoma-orthogonal",
)
.expect("must render");
assert!(
dotted.contains(&format!(
"stroke-dasharray=\"{}\"",
theme::Theme::for_routing("dark", Routing::Orthogonal)
.tokens
.map_or(super::svg::DOTTED_DASH, |t| t.dotted_dash)
)),
"an author-dashed back edge must keep drawing dashed: {dotted}"
);
}
/// Finding 6 (medium): `[ui] mermaid_curve` / `%%{init}%%`'s `flowchart.curve` only mean anything
/// under `"splines"` (`docs/FEATURE-MERMAID-RENDERER.md` §10-2's own "orthogonal は折れ線なので
/// curve の概念が無い"); under `"konoma-orthogonal"` a curve name must be a complete no-op on the
/// emitted bytes. `orthogonal_splines_routing_is_deterministic_and_does_not_panic` states the
/// analogous fact for `"splines"` itself (curve resolution is decidable and non-panicking); this is
/// the missing byte-identity half for `"konoma-orthogonal"`.
#[test]
fn orthogonal_routing_ignores_mermaid_curve_and_the_init_directive() {
for (name, src) in CORPUS {
let basis = render_flow(src, "dark", "basis", "konoma-orthogonal")
.unwrap_or_else(|e| panic!("{name}: basis must render: {e}"));
for curve in ["linear", "step", "monotoneX", "bumpX"] {
let other = render_flow(src, "dark", curve, "konoma-orthogonal")
.unwrap_or_else(|e| panic!("{name}/{curve}: must render: {e}"));
assert_eq!(
basis, other,
"{name}: konoma-orthogonal must ignore mermaid_curve={curve} entirely"
);
}
}
// The `%%{init}%%` directive's own `flowchart.curve` must be equally inert.
let plain = render_flow(
"flowchart TD\n A --> B --> C",
"dark",
"basis",
"konoma-orthogonal",
)
.expect("must render");
let with_init = render_flow(
"%%{init: {\"flowchart\": {\"curve\": \"stepBefore\"}}}%%\nflowchart TD\n A --> B --> C",
"dark",
"basis",
"konoma-orthogonal",
)
.expect("must render");
assert_eq!(
plain, with_init,
"konoma-orthogonal must ignore an `%%{{init}}%%` flowchart.curve directive too"
);
}
/// Finding 8a (medium): a self-loop is never a "detour" edge for §10-1 item 4's 12px crossing gap
/// (`orthogonal::insert_crossing_gaps`'s own `is_detour` excludes it via `source.id != target.id`)
/// — so when a self-loop and a genuine detour edge cross in real pixels (`orthogonal-self-loop-
/// crosses`, dumped and confirmed to cross), the self-loop must never be the side that gets cut, and
/// the crossing detour edge must be.
#[test]
fn orthogonal_self_loop_never_gets_cut_by_a_crossing_gap() {
if !text_metrics::fonts_available() {
return;
}
let src = orthogonal_only_corpus()
.into_iter()
.find(|(name, _)| *name == "orthogonal-self-loop-crosses")
.unwrap()
.1;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let loop_edge = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "A")
.expect("the self-loop must exist");
assert!(
loop_edge.gaps.is_empty(),
"a self-loop must never be the spanning side of a crossing gap: {:?}",
loop_edge.gaps
);
let detour = d
.edges
.iter()
.find(|e| e.from == "C" && e.to == "B")
.expect("C->B must exist");
assert!(
!detour.gaps.is_empty(),
"the fixture must actually reproduce a real crossing against the self-loop, so C->B must \
be the one carrying the gap: {:?}",
detour.gaps
);
// And, directly: the fixture's own premise — the self-loop's bump and C->B's detour actually
// occupy overlapping space in real pixels — confirmed by their bounding boxes overlapping on
// both axes (the two polylines' own extents, not just "a gap happened to appear somewhere").
let bbox = |pts: &[Point]| -> (f64, f64, f64, f64) {
let (mut l, mut t, mut r, mut b) = (
f64::INFINITY,
f64::INFINITY,
f64::NEG_INFINITY,
f64::NEG_INFINITY,
);
for p in pts {
l = l.min(p.x);
t = t.min(p.y);
r = r.max(p.x);
b = b.max(p.y);
}
(l, t, r, b)
};
let (dx, dy) = rect_overlap(bbox(&loop_edge.points), bbox(&detour.points));
assert!(
dx > 0.0 && dy > 0.0,
"fixture must reproduce a real overlap in space between the self-loop and C->B, not just \
a coincidental gap: loop_bbox={:?} detour_bbox={:?}",
bbox(&loop_edge.points),
bbox(&detour.points)
);
}
/// Finding 8b (medium): a self-loop never occupies a perimeter lane index
/// (`orthogonal::perimeter_lanes`'s own filter: `s.reverse && source.id != target.id`) — so adding
/// or removing a self-loop on a node that is *also* part of a genuine back-edge cycle must not shift
/// the back edge's own lane (and therefore its ring distance) at all. Pinned by comparing two
/// otherwise-identical sources, one with the self-loop and one without.
#[test]
fn orthogonal_self_loop_does_not_consume_a_perimeter_lane() {
if !text_metrics::fonts_available() {
return;
}
let with_loop = laid_out_flow(
"flowchart TD\n A --> A\n A --> B\n B --> C\n C --> A",
"basis",
"konoma-orthogonal",
);
let without_loop = laid_out_flow(
"flowchart TD\n A --> B\n B --> C\n C --> A",
"basis",
"konoma-orthogonal",
);
let ca_with = with_loop
.edges
.iter()
.find(|e| e.from == "C" && e.to == "A")
.expect("C->A must exist");
let ca_without = without_loop
.edges
.iter()
.find(|e| e.from == "C" && e.to == "A")
.expect("C->A must exist");
// The rule is about the **lane**: `perimeter_lanes` hands out ring offsets, and a self-loop
// must never take one, so the back edge's ring leg has to sit at exactly the same coordinate
// either way. That is asserted directly.
//
// It used to be asserted through the whole route being byte-identical, which was a proxy and
// stopped being a true one when §10-8's node sizes landed (2026-09-05): with `A` a full 96px
// wide, `C -> A` can reach `A`'s Right face centre when nothing else is on it, and a flowchart
// self-loop **is** something else on it (`route_flowchart`'s own `fixed_self_loops` is `false`
// for a flowchart, so its two ports are ordinary claims on `evict`'s grid — only a state
// diagram's self-transition gets the dedicated §10-5 S3 pair). So the back edge legitimately
// enters a different *face* when the loop is there, while riding the identical ring lane. The
// ring leg is the thing `perimeter_lanes` decides and the thing this test is named for.
let ring_leg = |e: &super::PlacedEdge| {
assert!(
e.points.len() >= 3,
"C->A rides the ring, so it has a leg between its two exits: {:?}",
e.points
);
e.points[1].x
};
assert!(
(ring_leg(ca_with) - ring_leg(ca_without)).abs() < 1e-6,
"C->A's own ring lane must be the same whether or not A also carries a self-loop (the \
self-loop must never consume a perimeter lane slot): with={:?} without={:?}",
ca_with.points,
ca_without.points
);
// And the lane is a real one on both sides — a ring leg that had collapsed onto the node's own
// face would compare equal to itself and say nothing.
let (_, _, a_right, _) = with_loop.node("A").expect("A must exist").bounds();
assert!(
ring_leg(ca_with) > a_right,
"C->A's ring leg must run outside A, not along its face: {:?}",
ca_with.points
);
}
/// Finding 10 (low, investigated): `MAX_GROWTH_PASSES = 3` (`mod.rs`'s own `lay_out_spec`) is a
/// defensive cap over a process the code's own doc states is monotonic and therefore always
/// converges on its own — `apply_growth` only ever grows toward an exact, one-shot-computable
/// minimum (`Eviction::required_size`), not an iterative approximation, so there is no obvious
/// adversarial input that forces three full passes rather than converging in one or two. A stress
/// source combining heavy fan-in (12 merge edges onto one face, forcing node growth) with long
/// labels (forcing `label_boosts` growth at the same time, `mod.rs`'s own doc: "a pass can ask for
/// both at once") was tried; `lay_out_spec` has no public hook that reports how many passes a given
/// input actually took, so whether this specific source reaches the cap could not be confirmed
/// directly. What is confirmed: the combined stress case renders without panicking and comes out
/// axis-parallel and collision-free, i.e. self-consistent regardless of how many passes it took —
/// the property finding 10 asked to be pinned "if reachable", stated unconditionally instead since
/// reachability itself could not be established.
#[test]
fn orthogonal_heavy_growth_stress_renders_self_consistently() {
if !text_metrics::fonts_available() {
return;
}
let mut src = String::from("flowchart TD\n");
for i in 1..=12 {
src.push_str(&format!(
" W{i}[extremely long sibling label number {i} to force both node and label growth at once] --> T\n"
));
}
src.push_str(" T -- also a long label on the way out --> X\n");
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
// Self-consistency: every segment axis-parallel, no edge crosses a foreign node's box.
for e in &d.edges {
for w in e.points.windows(2) {
let dx = (w[1].x - w[0].x).abs();
let dy = (w[1].y - w[0].y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"heavy-growth stress: {}->{} must stay axis-parallel: {w:?}",
e.from,
e.to
);
}
for n in &d.nodes {
if n.id == e.from || n.id == e.to {
continue;
}
for w in e.points.windows(2) {
assert!(
!orthogonal::segment_crosses_node(&w[0], &w[1], n),
"heavy-growth stress: {}->{} crosses foreign node {}",
e.from,
e.to,
n.id
);
}
}
}
// And render_flow (the SVG-emitting entry point) must not panic on the same source either.
render_flow(&src, "dark", "basis", "konoma-orthogonal").expect("must render");
}
/// Finding 11 (low): degenerate flowcharts under `"konoma-orthogonal"` must not panic. A single
/// node with no edges at all exercises `lay_out_spec`'s growth loop with an empty `eligible` list
/// (`spec.routing == Routing::Orthogonal` but nothing to route); a self-loop on a lone node
/// exercises the one-node/one-edge case of every pass (`evict`, `align_straight_lanes`,
/// `insert_crossing_gaps`) at once.
#[test]
fn orthogonal_degenerate_diagrams_do_not_panic() {
if !text_metrics::fonts_available() {
return;
}
for src in ["flowchart TD\n A[only]", "flowchart TD\n A --> A"] {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for e in &d.edges {
for w in e.points.windows(2) {
let dx = (w[1].x - w[0].x).abs();
let dy = (w[1].y - w[0].y).abs();
assert!(
dx < AXIS_EPS || dy < AXIS_EPS,
"{src:?}: {}->{} must stay axis-parallel: {w:?}",
e.from,
e.to
);
}
}
render_flow(src, "dark", "basis", "konoma-orthogonal")
.unwrap_or_else(|e| panic!("{src:?} must render under konoma-orthogonal: {e}"));
}
}
/// [`orthogonal_degenerate_diagrams_do_not_panic`]'s remaining case — two nodes placed at the exact
/// same centre — cannot be produced through a real mermaid source at all (dagre always separates
/// same-rank nodes by `nodesep`), so it is stated directly against [`orthogonal::route_edge`]
/// instead, the same private-access shortcut `orthogonal.rs`'s own unit tests use.
#[test]
fn orthogonal_route_edge_does_not_panic_on_coincident_centres() {
let a = placed_node("A", 100.0, 100.0, 60.0, 40.0);
let b = placed_node("B", 100.0, 100.0, 60.0, 40.0);
// `route_edge` is `pub`; the coincident-centre case is exercised through it rather than the
// private `route_flowchart`/`evict` pair this file has no direct access to.
let pts = orthogonal::route_edge(
crate::preview::mermaid::flowchart::Direction::TopToBottom,
&a,
&b,
&[],
Some(0),
Some(1),
1,
1,
);
assert!(
!pts.is_empty(),
"must return a non-empty polyline, not panic"
);
for p in &pts {
assert!(
p.x.is_finite() && p.y.is_finite(),
"must never emit a NaN/infinite point: {p:?}"
);
}
}
// ---------------------------------------------------------------------------------------------
// TEMP probe for docs/FEATURE-MERMAID-RENDERER.md §10-3 work — dumps a markdown file's own mermaid
// fences under `konoma-orthogonal` to `docs/render-check` for structural/visual comparison against
// hand-drawn reference SVGs. `#[ignore]`d so it never runs in the normal battery.
/// Dumps every mermaid fence in `md_path` to `docs/render-check/<stem>-NN-konoma-orthogonal.{svg,png}`
/// — `dump_mermaid_ja_corpus_under_orthogonal` and `dump_render_check_probes_under_orthogonal`'s
/// own shared body, factored out once a second source (`docs/render-check/zz-design-sources.md`,
/// `docs/render-check/zz-design-longedge-probe.md`) needed the identical treatment.
fn dump_fences_under_orthogonal(md_path: &str, stem: &str) {
let md = std::fs::read_to_string(md_path).unwrap_or_else(|e| panic!("read {md_path}: {e}"));
let mut fences: Vec<String> = Vec::new();
let mut cur: Option<String> = None;
for line in md.lines() {
if let Some(buf) = &mut cur {
if line.trim() == "```" {
fences.push(std::mem::take(buf));
cur = None;
} else {
buf.push_str(line);
buf.push('\n');
}
} else if line.trim() == "```mermaid" {
cur = Some(String::new());
}
}
assert!(
!fences.is_empty(),
"{md_path}: must find at least one mermaid fence"
);
for (i, code) in fences.iter().enumerate() {
let n = i + 1;
let path = format!("docs/render-check/{stem}-{n:02}-konoma-orthogonal.svg");
// `[ui] mermaid_routing` only ever means anything for a flowchart (`mod.rs`'s own doc) —
// every other diagram kind renders through the ordinary `render`, unaffected by it.
// `[ui] mermaid_routing` only ever means anything for a flowchart — this is the real
// dispatcher every other diagram kind goes through in production
// (`preview::markdown::mermaid_to_svg_reason_flow`), not `render_flow` alone (which only
// ever knows how to parse a flowchart).
let svg = crate::preview::markdown::mermaid_to_svg_flow(
code,
"dark",
"basis",
"konoma-orthogonal",
);
match svg {
Some(svg) => {
std::fs::write(&path, &svg).unwrap_or_else(|e| panic!("write {path}: {e}"));
let png_path = format!("docs/render-check/{stem}-{n:02}-konoma-orthogonal.png");
if let Some(img) = crate::preview::svg::rasterize_bytes(
svg.as_bytes(),
std::path::Path::new(&path),
2400,
) {
img.save(&png_path)
.unwrap_or_else(|e| panic!("save {png_path}: {e}"));
}
}
None => eprintln!("{md_path} fence {n}: render failed"),
}
}
}
/// Dumps the "大きさ" flowchart (`samples/mermaid.ja.md` fence 3) to `docs/render-check` for
/// structural comparison against the round3 handoff's 3a SVG, and every other
/// `samples/mermaid.ja.md` fence for the same visual spot-check. Run explicitly with
/// `cargo test --features git dump_mermaid_ja_corpus_under_orthogonal -- --ignored --nocapture`.
#[test]
#[ignore]
fn dump_mermaid_ja_corpus_under_orthogonal() {
dump_fences_under_orthogonal("samples/mermaid.ja.md", "mermaid.ja");
}
/// Dumps `docs/render-check/zz-design-sources.md` (2a/2b/2c-equivalent sources — a worker subgraph,
/// LR/TB nested-subgraph client/cloud/external graphs) and `docs/render-check/zz-design-longedge-
/// probe.md` (`CORPUS`'s own `long-edge` source, standalone, for the exact regression this session's
/// pass-through-reservation fix closes) to `docs/render-check`, for the general-corpus checks
/// `docs/FEATURE-MERMAID-RENDERER.md` §10-3's own implementation notes on this session's three
/// findings describe. Run explicitly with `cargo test --features git
/// dump_render_check_probes_under_orthogonal -- --ignored --nocapture`.
#[test]
#[ignore]
fn dump_render_check_probes_under_orthogonal() {
dump_fences_under_orthogonal(
"docs/render-check/zz-design-sources.md",
"zz-design-sources",
);
dump_fences_under_orthogonal(
"docs/render-check/zz-design-longedge-probe.md",
"zz-design-longedge-probe",
);
}
/// §10-3 item 13's own regression, found by generalising past `CORPUS` to real, larger sources
/// (`docs/render-check/zz-design-sources.md`'s `2b`): `API -> ID`, a cross-subgraph node-to-node
/// edge whose `classify`-decided shape is `staircase` (`raw` carries 13 dagre waypoints, several
/// collinear before ever reaching `ID`'s own port). `clear_local_route`'s own crossing search can
/// flag an *early* window of that collinear run, not the literal last one — an earlier draft of the
/// local-detour fix (§10-3 item 13) judged whether a port sat on the coordinate being moved by the
/// *literal window index* (`i + 2 == points.len()`) rather than by coordinate, so it never noticed
/// `ID`'s own port shared the exact coordinate an early window's fix slid out from under it: a
/// diagonal final segment, `orthogonal_routing_draws_only_axis_parallel_segments`'s own invariant
/// broken in a shape `CORPUS` had no fixture for. Pinned here directly, not only through the
/// corpus-wide invariant, because this is the exact real-world diagram the bug was found on
/// (`local_detour`'s own current implementation never slides a shared coordinate at all — it
/// detours only the interior span between two freshly-inserted boundary points either side of the
/// obstacle, so this specific failure mode cannot recur, but the fixture stays as a named regression
/// test for the general "port coordinate coincides with an obstacle boundary" shape).
#[test]
fn orthogonal_cross_subgraph_edge_never_draws_a_diagonal_segment() {
let src = "flowchart LR\n subgraph C[クライアント]\n CLI[CLI]\n UI[ブラウザ UI]\n EX[エディタ拡張]\n end\n subgraph G[クラウド]\n API[API ゲート]\n Q[ジョブキュー]\n W[ジョブ実行系]\n SB[解析サンドボックス]:::exec\n subgraph S[保存層]\n DB[メタデータ DB]:::data\n AR[成果物保管]:::data\n end\n end\n subgraph E[外部]\n ID[認証基盤]\n LLM[モデル API]:::model\n GIT[コード置き場]:::exec\n PAY[決済ページ]\n end\n CLI --> API\n UI -->|HTTPS| API\n EX --> API\n API --> ID\n API -->|投入| Q\n Q -->|取り出し| W\n API --> DB\n W --> DB\n W --> AR\n W --> LLM\n W -->|ツール実行| SB\n SB --> GIT\n CLI -.->|リンク| PAY\n classDef data fill:#161b22,stroke:#3fb950,color:#e6edf3\n classDef model fill:#161b22,stroke:#a371f7,color:#e6edf3\n classDef exec fill:#161b22,stroke:#f85149,color:#e6edf3\n linkStyle 0,1,2 stroke:#58a6ff\n linkStyle 4,5 stroke:#d29922\n";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let api_id = d
.edges
.iter()
.find(|e| e.from == "API" && e.to == "ID")
.expect("API->ID must exist");
for w in api_id.points.windows(2) {
let (a, b) = (&w[0], &w[1]);
assert!(
(a.x - b.x).abs() < AXIS_EPS || (a.y - b.y).abs() < AXIS_EPS,
"API->ID must never draw a diagonal segment: {:?}-{:?} in {:?}",
a,
b,
api_id.points
);
}
}
#[test]
fn zzdebug_fence3_structural_table() {
let src = "flowchart LR\n F[ファイル] --> C{設定のルール}\n C -->|テキスト| T[窓読み]\n C -->|コード| S[構文強調]\n C -->|Markdown| MD[ブロックモデル]\n C -->|CSV / TSV| TB[表]\n C -->|画像| IM[デコード]\n C -->|PDF| PD[ページ描画]\n C -->|SVG| SV[usvg]\n C -->|動画| VD[キーフレーム]\n C -->|書庫| AR[一覧]\n C -->|なし| NA[プレビュー不可]\n MD --> MM[mermaid]\n MD --> MA[数式]\n MM --> RS[ラスタライズ]\n MA --> RS\n SV --> RS\n PD --> RS\n IM --> FIT[セルに合わせる]\n RS --> FIT\n VD --> FIT\n FIT --> K{端末}\n K -->|kitty| KT[圧縮転送]\n K -->|sixel / iTerm2| RI[画像プロトコル]\n K -->|それ以外| HB[ハーフブロック]\n classDef pix fill:#132a3a,stroke:#1f6feb,color:#c9d1d9\n classDef txt fill:#12291c,stroke:#2da44e,color:#c9d1d9\n class IM,PD,SV,VD,MM,MA,RS,FIT,KT,RI,HB pix\n class T,S,MD,TB,AR txt\n style NA fill:#2d2418,stroke:#d4a017,color:#c9d1d9\n";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for n in &d.nodes {
eprintln!(
"NODE {:>4}: center=({:.1},{:.1}) size=({:.1}x{:.1}) box=[{:.1}..{:.1}]x[{:.1}..{:.1}]",
n.id,
n.center.x,
n.center.y,
n.size.w,
n.size.h,
n.center.x - n.size.w / 2.0,
n.center.x + n.size.w / 2.0,
n.center.y - n.size.h / 2.0,
n.center.y + n.size.h / 2.0,
);
}
for e in &d.edges {
let bends = e.points.len().saturating_sub(2);
eprintln!(
"{:>3} -> {:<3} bends={} start={:?} end={:?} color={:?} points={:?}",
e.from,
e.to,
bends,
e.points.first(),
e.points.last(),
e.style.as_ref().and_then(|s| s.stroke.clone()),
e.points,
);
}
}
/// §10-3's "ファン列内の並び順" (`docs/FEATURE-MERMAID-RENDERER.md`, `mod.rs`'s own `regroup_fan_
/// lanes` doc) — the mechanical rule reverse-engineered from `3a`'s reference geometry, pinned on
/// a small, hand-built fan deliberately shaped to make every clause of the rule independently
/// checkable, rather than only on `samples/mermaid.ja.md`'s 20-node fence (the real-world source
/// the rule was derived from, covered separately by `orthogonal_settings_rules_sample_*`):
///
/// `S` fans out to six children, in declaration order `A`(red), `P`(blue), `B`(red), `T`(red,
/// *and* the sole one with its own further out-edge — `T -> D` — so it is the unambiguous trunk
/// regardless of any geometric tie-break), `Q`(blue), `Z`(no `class` at all, only `classDef`
/// members get one). The rule (trunk → group index `len/2`; group by resolved colour, group order
/// by first declared member; classless always last) predicts, and this test pins, the exact order
/// `A, B, P, T, Q, Z`: the two same-coloured groups (`red` first, since `A` is declared before
/// `P`) supply `regroup_fan_lanes`'s own `rest` list `[A, B, P, Q, Z]` (classless `Z` pushed to
/// the tail regardless of its own declaration position, third of six), and inserting `T` at
/// `6 / 2 = 3` splits it `[A, B, P]` / `[T]` / `[Q,Z]`.
///
/// Each assertion below is aimed at one clause a mutation of the rule would silently break:
/// swapping the group-order key (first-declared member) would put `P` ahead of `A`; dropping the
/// "同色内は安定" clause (or resorting a group by id instead of declaration order) would put `B`
/// ahead of `A` or `Q` ahead of `P`; treating the classless rule as "first" instead of "last"
/// would move `Z` to the front; using `len/2` rounded the other way, or not special-casing the
/// trunk's own slot at all, would misplace `T`; and dropping [`orthogonal::evict`]'s own anchor
/// fix (this module's own `orthogonal_branch_and_merge_edges_share_a_face_one_aligned_one_bends_
/// twice`, the general-purpose regression for the same fix) would leave `S -> T` bent instead of
/// the straight, exactly-centred line the last two assertions pin.
#[test]
fn regroup_fan_lanes_groups_by_colour_centres_the_trunk_and_pushes_classless_outermost() {
let src = "flowchart LR\n S --> A\n S --> P\n S --> B\n S --> T\n S --> Q\n S --> Z\n \
T --> D\n classDef red stroke:#ff0000\n classDef blu stroke:#0000ff\n \
class A,B red\n class P,Q blu\n";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
assert_no_edge_crosses_its_own_endpoint("regroup-minimal", &d);
check_nodes_do_not_overlap("regroup-minimal", &d);
let mut kids: Vec<(&str, f64)> = d
.edges
.iter()
.filter(|e| e.from == "S")
.map(|e| (e.to.as_str(), d.node(&e.to).unwrap().center.y))
.collect();
kids.sort_by(|a, b| a.1.partial_cmp(&b.1).unwrap());
let order: Vec<&str> = kids.iter().map(|(id, _)| *id).collect();
assert_eq!(
order,
vec!["A", "B", "P", "T", "Q", "Z"],
"colour-grouped, trunk-centred, classless-outermost order: {order:?}"
);
// The trunk edge is `classify`'s `aligned` shape (a straight 2-point line), landing exactly
// on S's own centre — `evict`'s anchor fix (§10-3's "幹7区間の曲げ0") is what makes this land
// on 0 rather than `PORT_SPACING/2` off it despite six claims (an even count) on S's face.
let st = d
.edges
.iter()
.find(|e| e.from == "S" && e.to == "T")
.expect("S->T must exist");
let s_node = d.node("S").expect("S must exist");
assert_eq!(
st.points.len(),
2,
"S->T is the trunk — a straight 2-point line: {:?}",
st.points
);
assert!(
(st.points[0].y - s_node.center.y).abs() < 1e-6,
"S->T exits exactly on S's own centre: {:?} vs {}",
st.points[0],
s_node.center.y
);
}
/// §10-3 item 11 (`docs/FEATURE-MERMAID-RENDERER.md`) — `regroup_fan_lanes` widened from "at least
/// three members" to "at least two": `samples/mermaid.ja.md`'s own `ブロックモデル` (`MD`) fans out
/// to exactly two children, `mermaid`(`MM`, the trunk `MD->MM` selects — its own further edge
/// `MM->RS` is what makes it the unambiguous chain continuation) and `数式`(`MA`, the sole non-
/// trunk member), and `3a`'s own reference geometry puts `数式` *above* `mermaid`, not below —
/// pinned directly on the real corpus source rather than only inferred from the `SETTINGS_RULES_
/// SAMPLE` dump this fix was found against. Before this fix, a plain two-way fan was never
/// eligible for `regroup_fan_lanes` at all (`docs/STATUS.md`'s own ★未修正 entry — "`regroup_fan_
/// lanes` は要素3以上のファンのみ対象" — before this fix, `MA` fell wherever `align_straight_
/// lanes`'s own overlap sweep happened to leave it, landing *below* `MM` instead).
#[test]
fn orthogonal_settings_rules_sample_block_model_fan_puts_math_above_the_mermaid_trunk() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mm = d.node("MM").expect("MM (mermaid) must exist");
let ma = d.node("MA").expect("MA (数式) must exist");
let mm_mm = d
.edges
.iter()
.find(|e| e.from == "MD" && e.to == "MM")
.expect("MD->MM must exist");
assert_eq!(
mm_mm.points.len(),
2,
"MD->MM is the trunk — a straight 2-point line: {:?}",
mm_mm.points
);
assert!(
ma.center.y < mm.center.y,
"数式(MA) must sit above the mermaid(MM) trunk under LR (smaller y): MA.y={}, MM.y={}",
ma.center.y,
mm.center.y
);
}
/// A minimal, hand-built counterpart to the corpus pin above, for the *other* half of
/// [`super::fan_split`]'s own one-branch rule: a two-way fan with no colour classes at all, whose
/// sole non-trunk branch is a **dead end** (`A` has no out-edge), goes *after* the trunk — the
/// positive cross side, `LR` down / `TB` right.
///
/// This test used to assert the opposite (`A` before `T`) and was named for it. That expectation
/// was the `before = len / 2` formula written down as if it were the rule, and
/// `docs/STATUS.md`'s own ★未修正 **G8** is what it cost: `zz-design-4b`'s own `休止` (a dead end
/// off `分岐`) came out *above* the `更新` trunk where every design reference puts it below. The
/// formula was reverse-engineered from `1b` and `3a`'s own `ブロックモデル`, and in **both** of those
/// the sole non-trunk branch happens to be one that continues (`1b`'s `画像 → デコード`, `3a`'s
/// `数式 → ラスタライズ`) — so "before" and "continues" were indistinguishable in the two examples
/// the formula came from. Run over all nine non-trunk branches of the design references at once,
/// only continuity explains them; this fixture is the case that separates the two readings, which
/// is why it is stated in both directions here.
#[test]
fn orthogonal_synthetic_two_way_fan_puts_a_dead_end_branch_after_the_trunk() {
// `LR` (cross axis is y: "after" is down) and `TB` (cross axis is x: "after" is right). The
// third case adds a self-loop on `A`: a branch that only loops back to itself is still a dead
// end (`regroup_fan_lanes`'s own `continues` doc), so nothing about its side changes.
for (direction, cross_of, extra) in [
(
"LR",
(|n: &PlacedNode| n.center.y) as fn(&PlacedNode) -> f64,
"",
),
("TB", |n: &PlacedNode| n.center.x, ""),
("LR", |n: &PlacedNode| n.center.y, " A --> A\n"),
] {
let src = format!("flowchart {direction}\n S --> A\n S --> T\n T --> D\n{extra}");
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let a = d.node("A").expect("A must exist");
let t = d.node("T").expect("T must exist");
let st = d
.edges
.iter()
.find(|e| e.from == "S" && e.to == "T")
.expect("S->T must exist");
assert_eq!(
st.points.len(),
2,
"{direction}: S->T is the trunk (T continues the chain via T->D) — a straight 2-point \
line: {:?}",
st.points
);
assert!(
cross_of(a) > cross_of(t),
"{direction}: the sole non-trunk branch (A) is a dead end, so it takes the positive \
cross side — after the trunk (T): A={:.1}, T={:.1}",
cross_of(a),
cross_of(t)
);
}
}
/// [`super::fan_split`]'s own two-branch case, in 1b's regime: **both** cross-axis faces are spoken
/// for whatever the branches' continuity is, so the split stays at the centre and the trunk keeps
/// one branch on each side.
///
/// Stated twice, once for each way the two branches can agree. Both continuing (`A -> P`, `B -> Q`)
/// is the configuration where a naive "every continuing branch goes before the trunk" would stack
/// both on one side and leave the other face empty; both dead ends is `3a`'s own `端末` fan
/// (`圧縮転送` above, `ハーフブロック` below `画像プロトコル`), where the same naive reading would
/// stack both *after* it. 1b's basic shape can seat neither.
#[test]
fn orthogonal_three_way_fan_whose_branches_agree_keeps_one_on_each_side() {
for (what, tail) in [
("both continue", " A --> P\n B --> Q\n"),
("both dead-end", ""),
] {
let src = format!("flowchart LR\n S --> A\n S --> T\n T --> D\n S --> B\n{tail}");
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let a = d.node("A").expect("A must exist");
let b = d.node("B").expect("B must exist");
let t = d.node("T").expect("T must exist");
assert!(
a.center.y < t.center.y && t.center.y < b.center.y,
"{what}: the trunk (T) keeps the centre slot with one branch either side: A.y={}, \
T.y={}, B.y={}",
a.center.y,
t.center.y,
b.center.y
);
}
}
/// `zz-design-2b`/`2c`'s own spine: **`API ゲート → ジョブキュー → ジョブ実行系 → 解析サンドボックス
/// → コード置き場` is one straight run, and the two `保存層` stores fan off to one side of it** — the
/// composition both design references draw, stated once for each axis (`2b` is `LR`, `2c` the same
/// graph `TB`).
///
/// `ジョブ実行系` has four out-edges and only `解析サンドボックス` continues (into `コード置き場`,
/// a member of a *different* frame), so `align_straight_lanes` picks it as the chain's own
/// continuation — that part was never in doubt. What was wrong is where the rank then put it:
/// `メタデータ DB` and `成果物保管` are members of `保存層` inside the same `クラウド` frame
/// `ジョブ実行系` and `解析サンドボックス` sit in, and every pass that spaces a rank read each node's
/// **outermost** frame, so all four counted as one indivisible unit and none of them was ever spaced
/// against another. `解析サンドボックス` came out at *exactly* the same point as `成果物保管`, and
/// `clear_foreign_cluster_overlaps` — which runs much later and knows nothing about lanes — broke
/// the tie by shoving the one that was foreign to `保存層`, i.e. the lane's own member, out of the
/// frame and off the spine. `成果物保管` was then left sitting on the lane, which is what read as
/// "`成果物保管` is the straight continuation".
///
/// Which side the two stores end up on is dagre's own rank order, not a rule of §10-3's, so this
/// asserts only that they are together and on *a* side, never which.
/// §10-3 item 4's own branch half (`orthogonal::EdgeShape::cross_lane_bend`), stated on a
/// synthetic diagram built from the *shape* the rule is about rather than from any reference
/// picture: a branching source whose long edge has to reach a target whose own column is occupied
/// (`T3` sits directly above `Far`) and whose own flow-axis column carries a trunk (`T1`/`T2`), so
/// neither of `classify`'s two ordinary shapes nor any flow-face rank-lane bend can clear.
///
/// Before this rule existed that combination fell to `staircase` — dagre's dummy waypoints, laid
/// out before the cross-axis passes moved every node, so the chain pointed at columns that no
/// longer held anything and `clear_local_route` walked it out and back in a nine-point zig-zag.
/// What is asserted here is the rule, not that route's absence: the edge leaves through the face
/// already turned towards its target, runs one straight leg down a lane that keeps
/// [`orthogonal::PORT_CLEARANCE`] from every node, and turns into the target's own flow face —
/// three bends, the two the rule allows plus the hop onto the lane.
#[test]
fn orthogonal_blocked_multi_rank_branch_runs_a_free_lane_off_the_face_facing_its_target() {
let src = "flowchart TB\n S --> T1\n T1 --> T2\n T2 --> T3\n T3 --> T4\n \
T2 --> Blk\n Blk --> Far\n S --> Far";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let e = d
.edges
.iter()
.find(|e| e.from == "S" && e.to == "Far")
.expect("S -> Far must be routed");
let s = d.node("S").expect("S");
let far = d.node("Far").expect("Far");
assert!(
far.center.x > s.center.x,
"fixture assumption: Far must sit on S's right, not at {:?}",
far.center
);
// Leaves through the cross-axis face already turned towards the target, not the flow face a
// `staircase` fallback would use.
let (_, _, s_right, _) = s.bounds();
assert!(
(e.points[0].x - (s_right + orthogonal::PORT_INSET)).abs() < AXIS_EPS
&& (e.points[0].y - s.center.y).abs() < AXIS_EPS,
"S -> Far must leave S's own right face at its centre, not {:?}: {:?}",
e.points[0],
e.points
);
assert_eq!(
e.points.len(),
5,
"S -> Far must be the rule's own four legs: {:?}",
e.points
);
// …into the target's flow-axis face.
let (far_l, far_t, far_r, _) = far.bounds();
let end = e.points.last().expect("non-empty");
assert!(
(end.y - (far_t - orthogonal::PORT_INSET)).abs() < AXIS_EPS
&& end.x > far_l
&& end.x < far_r,
"S -> Far must enter Far's own top face, not {end:?}: {:?}",
e.points
);
// The lane itself: one straight run along the flow axis, clear of every node's column by at
// least the module's own minimum port clearance on both sides.
let lane = e.points[1].x;
assert!(
(e.points[2].x - lane).abs() < AXIS_EPS && (e.points[2].y - e.points[1].y).abs() > 100.0,
"S -> Far's own second leg must be the long lane run: {:?}",
e.points
);
for n in &d.nodes {
if n.id == "S" || n.id == "Far" {
continue;
}
let (l, t, r, b) = n.bounds();
let spans_the_run = t < e.points[2].y && b > e.points[1].y;
assert!(
!spans_the_run
|| lane <= l - orthogonal::PORT_CLEARANCE
|| lane >= r + orthogonal::PORT_CLEARANCE,
"S -> Far's lane at x={lane:.2} is closer than {}px to {} {:?}",
orthogonal::PORT_CLEARANCE,
n.id,
n.bounds()
);
}
}
/// §10-5 round 4's own headline rule — "枠は 1 つの単位…ブロックは 1 つの body として動く"
/// ([`orthogonal::LaneUnits::unit_of`]) — stated where it actually has consequences, because
/// nothing stated it before: making that method the identity (every node its own unit) left the
/// whole suite green for a while, which means "a block moves as a body" was believed rather than
/// checked.
///
/// Two consequences, one per fixture, both of which the identity mutation breaks:
///
/// 1. **A lane that crosses a frame moves the block, it does not stretch it.** `A --> c2` reaches a
/// member in the middle of a block whose own spine is `c1 --> c2` with `c3` off to the side, so
/// aligning `A --> c2 --> B` has to move `c2`. Moving `c2` alone tears the block open — measured
/// at a 414.8px-wide frame for three 74.8px boxes. A block is only ever as wide as its own
/// members need, whatever a lane does to it.
/// 2. **A neighbour is spaced from the frame, not from a member.** `N` sits beside a block whose
/// nearest member (`c3`) stops well short of the frame's own border, so "spaced by
/// [`ORTHO_NODE_SEP`]" has two possible readings and only one of them leaves the drawn boxes
/// that far apart. Under the identity mutation the sweep never sees the frame at all and `N`
/// ends up wherever `clear_foreign_cluster_overlaps` shoves it — 16px out, not 24.
#[test]
fn orthogonal_a_block_moves_as_one_body_and_is_spaced_as_one() {
// (1) an outside lane through the middle of a block.
let d = laid_out_flow(
"flowchart TB\n A --> c2\n subgraph C\n c1 --> c2\n c1 --> c3\n end\n c2 --> B",
"basis",
"konoma-orthogonal",
);
let frame = d.cluster("C").expect("C");
let members: Vec<&PlacedNode> = ["c1", "c2", "c3"]
.iter()
.filter_map(|id| d.node(id))
.collect();
// The widest a rank inside this block can legitimately be: its own boxes, side by side, one
// `ORTHO_NODE_SEP` apart — plus the frame's own padding on each side.
let mut widest_rank = 0.0_f64;
for m in &members {
let row: Vec<&&PlacedNode> = members
.iter()
.filter(|o| (o.center.y - m.center.y).abs() < 1.0)
.collect();
let spread: f64 = row.iter().map(|o| o.size.w).sum::<f64>()
+ super::ORTHO_NODE_SEP * (row.len().saturating_sub(1)) as f64;
widest_rank = widest_rank.max(spread);
}
let allowed = widest_rank + 2.0 * clusters::PAD;
assert!(
frame.size.w <= allowed + 0.01,
"the lane through C stretched the block instead of moving it: frame is {:.2}px wide, \
its own members need {allowed:.2}px",
frame.size.w
);
// (2) a neighbour beside a block whose nearest member stops short of the frame.
let d = laid_out_flow(
"flowchart TB\n A --> c1\n A --> N\n N --> M\n subgraph C\n c1 --> c2\n \
c1 --> c3\n end\n c2 --> M",
"basis",
"konoma-orthogonal",
);
let frame = d.cluster("C").expect("C");
let n = d.node("N").expect("N");
let (fl, _, fr, _) = frame.bounds();
let (nl, _, nr, _) = n.bounds();
let gap = if nl >= fr { nl - fr } else { fl - nr };
assert!(
(gap - super::ORTHO_NODE_SEP).abs() < 0.01,
"N must sit {}px from C's own frame ({fl:.2}..{fr:.2}), not {gap:.2}px — it is at \
{nl:.2}..{nr:.2}",
super::ORTHO_NODE_SEP
);
}
/// §10-3 item 8's own ASAP re-ranking, on the one graph shape that used to switch it off for the
/// **whole diagram**: an edge that leaves a block and comes straight back into it
/// (`subgraph C { c1 --> c2 }` plus `c1 --> X --> c2`). Counting only the levels `C`'s own members
/// occupy made `c1` and `c2` adjacent, and the unit graph then stated `X` after `C` and `C` after
/// `X` at once — unsatisfiable, so the bounded relaxation never settled and `pull_back_fan_ranks`
/// returned without re-ranking anything, fans included.
///
/// Two things are asserted, and the second is the point: the returning node keeps its own level
/// between the two members (which is where dagre already had it, and the only place a forward
/// route can reach it from), **and** the four-way fan further down still gets its ASAP layer —
/// every `d*` on one rank, immediately after `c2`, with nothing between.
#[test]
fn orthogonal_a_block_leaving_and_returning_edge_still_leaves_asap_running() {
let src = "flowchart TB\n subgraph C\n c1 --> c2\n end\n c1 --> X\n X --> c2\n \
c2 --> d1\n c2 --> d2\n c2 --> d3\n c2 --> d4";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let y = |id: &str| d.node(id).unwrap_or_else(|| panic!("{id}")).center.y;
assert!(
y("c1") < y("X") && y("X") < y("c2"),
"X must keep its own level between c1 ({:.2}) and c2 ({:.2}), not {:.2}",
y("c1"),
y("c2"),
y("X")
);
// ASAP: the fan is one rank, and it is the rank immediately after `c2` — no empty column, and
// no member left behind on a later one. Read as "every `d*` shares a row, and the gap from
// `c2` to that row is the same as the gap `c1`'s own straight successor got".
let fan: Vec<f64> = ["d1", "d2", "d3", "d4"].iter().map(|id| y(id)).collect();
for w in fan.windows(2) {
assert!(
(w[0] - w[1]).abs() < 0.01,
"the fan under c2 must be one rank: {fan:?}"
);
}
let rows: std::collections::BTreeSet<i64> = d
.nodes
.iter()
.map(|n| (n.center.y * 100.0) as i64)
.collect();
assert_eq!(
rows.len(),
4,
"the diagram must re-rank to four rows (c1 / X / c2 / the fan), not {}: {:?}",
rows.len(),
d.nodes
.iter()
.map(|n| (n.id.as_str(), n.center.y))
.collect::<Vec<_>>()
);
}
/// Two sibling subgraphs on the same rank, with a title long enough on one of them that dagre's
/// own placement leaves the other's member inside it — the shape that exercises both halves of
/// "a frame is spaced and reserved like one body":
///
/// 1. §10-1 item 4's own "枠とノード・外周レーンの余白は最低16px" read for a frame *pair*:
/// `clear_foreign_cluster_overlaps` used to push the bare member box clear by
/// [`orthogonal::PERIMETER_MARGIN`], and `rebuild_frames` then wrapped that member in exactly
/// the same [`clusters::PAD`] — so `B`'s left edge landed precisely on `A`'s right edge and the
/// two frames shared a line. The push is by body now, and the gap is the rank's own
/// [`ORTHO_NODE_SEP`].
/// 2. `pull_back_fan_ranks`'s own column gaps: the room a frame's edge needs past its first member
/// column was *summed* over every block starting there, so two siblings reserved two heads' worth
/// of gap where the picture only ever shows one. Nesting sums (one frame really is beyond the
/// other); siblings take the maximum.
#[test]
fn orthogonal_sibling_frames_are_spaced_apart_and_reserve_one_column_gap() {
let src = "flowchart TB\n s --> a1\n s --> b1\n subgraph A[A very very very very very very very very very long title]\n a1\n end\n subgraph B[B]\n b1\n end";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let (a, b) = (d.cluster("A").expect("A"), d.cluster("B").expect("B"));
let (_, _, ar, _) = a.bounds();
let (bl, _, _, _) = b.bounds();
assert!(
(bl - ar - super::ORTHO_NODE_SEP).abs() < 0.01,
"two sibling frames must sit {}px apart, not {:.2}px (A ends at {ar:.2}, B starts at \
{bl:.2})",
super::ORTHO_NODE_SEP,
bl - ar
);
// One column gap, not two: `s`'s own bottom to the frames' top is exactly `RANK_SEP`, and from
// there to the member inside is that one frame's own head (its padding plus its title band).
let s = d.node("s").expect("s");
let (_, _, _, s_bottom) = s.bounds();
for frame in [a, b] {
let (_, ft, _, _) = frame.bounds();
assert!(
(ft - s_bottom - super::RANK_SEP).abs() < 0.01,
"frame {} must start {}px below s (which ends at {s_bottom:.2}), not {:.2}px — a \
sibling's own head must not be reserved twice",
frame.id,
super::RANK_SEP,
ft - s_bottom
);
}
}
/// The same rule on the two design references it was found on: `zz-design-2b`/`2c`'s own
/// `API ゲート --> 認証基盤`, a four-rank branch whose direct column holds `メタデータ DB` and
/// whose flow column holds the `投入` trunk.
///
/// Two things are pinned, both of them the rule rather than the picture: the edge leaves through
/// whichever cross-axis face actually faces `認証基盤` (`2c`'s left, `2b`'s top — the axis flip is
/// why both are here), and its long lane keeps clear of every **frame** it does not itself belong
/// to. That second half is what makes `cross_lane_bends` read subgraph frames at all: without it
/// `2c`'s nearest free lane is the 24px gap *between* `メタデータ DB` and `成果物保管`, which draws
/// the line straight down the middle of `保存層`'s own rectangle.
#[test]
fn orthogonal_design_2b_2c_auth_edge_takes_a_free_lane_off_the_face_facing_it() {
for name in ["zz-design-2b", "zz-design-2c"] {
let (_, src) = orthogonal_design_reference_corpus()
.into_iter()
.find(|(n, _)| *n == name)
.expect("design reference");
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let e = d
.edges
.iter()
.find(|e| e.from == "API" && e.to == "ID")
.expect("API -> ID must be routed");
let api = d.node("API").expect("API");
let id = d.node("ID").expect("ID");
let (l, t, r, b) = api.bounds();
let start = &e.points[0];
// `2c` is TB, so the cross axis is horizontal and `ID` sits to the left; `2b` is LR, so it
// is vertical and `ID` sits above. Either way: the face on the side the target is on.
let leaves_towards = if name == "zz-design-2c" {
(start.x - (l - orthogonal::PORT_INSET)).abs() < AXIS_EPS && id.center.x < api.center.x
} else {
(start.y - (t - orthogonal::PORT_INSET)).abs() < AXIS_EPS && id.center.y < api.center.y
};
assert!(
leaves_towards,
"{name}: API -> ID must leave the face facing 認証基盤, not {start:?} \
(API {:?}, ID {:?}): {:?}",
(l, t, r, b),
id.bounds(),
e.points
);
assert!(
e.points.len() <= 5,
"{name}: API -> ID must not need more than the rule's own four legs: {:?}",
e.points
);
for c in &d.clusters {
let (cl, ct, cr, cb) = c.bounds();
let holds = |p: &crate::preview::mermaid::layout::Point| {
p.x >= cl && p.x <= cr && p.y >= ct && p.y <= cb
};
if holds(&api.center) || holds(&id.center) {
continue; // the frames this edge starts inside / ends inside are not obstacles
}
for w in e.points.windows(2) {
let vertical = (w[0].x - w[1].x).abs() < AXIS_EPS;
let (lane, lo, hi) = if vertical {
(w[0].x, cl, cr)
} else {
(w[0].y, ct, cb)
};
let (run_lo, run_hi) = if vertical {
(w[0].y.min(w[1].y), w[0].y.max(w[1].y))
} else {
(w[0].x.min(w[1].x), w[0].x.max(w[1].x))
};
let (frame_lo, frame_hi) = if vertical { (ct, cb) } else { (cl, cr) };
if run_hi <= frame_lo || run_lo >= frame_hi {
continue; // this leg never reaches the frame's own extent along its own axis
}
assert!(
lane <= lo - orthogonal::PORT_CLEARANCE
|| lane >= hi + orthogonal::PORT_CLEARANCE,
"{name}: API -> ID's leg at {lane:.2} runs inside the foreign frame {} \
{:?}: {:?}",
c.id,
c.bounds(),
e.points
);
}
}
}
}
/// The set of `(name, source, direction)` triples §10-5 round 5's own tier rule
/// (`orthogonal::place_dead_end_tiers`) is stated over: both design references, plus the same
/// shape reduced to a plain chain in each direction so nothing about the rule can be reading a
/// coincidence of those two particular pictures.
fn tier_cases() -> Vec<(
&'static str,
String,
crate::preview::mermaid::flowchart::Direction,
)> {
use crate::preview::mermaid::flowchart::Direction;
let design = |name: &str| -> String {
orthogonal_design_reference_corpus()
.into_iter()
.find(|(n, _)| *n == name)
.unwrap_or_else(|| panic!("{name} is in the design-reference corpus"))
.1
.to_string()
};
// `A --> B --> C --> E` is the lane; `store` holds two dead ends fed from two *different*
// nodes of it, which is `保存層`'s own shape with every incidental detail stripped out.
let chain = |dir: &str| -> String {
format!(
"flowchart {dir}\n A --> B\n B --> C\n C --> E\n subgraph T[store]\n t1\n \
t2\n end\n A --> t1\n C --> t2"
)
};
vec![
(
"zz-design-2b",
design("zz-design-2b"),
Direction::LeftToRight,
),
(
"zz-design-2c",
design("zz-design-2c"),
Direction::TopToBottom,
),
("chain-lr", chain("LR"), Direction::LeftToRight),
("chain-tb", chain("TB"), Direction::TopToBottom),
]
}
/// §10-5 round 5's own **tier** rule, stated on the finished picture
/// (`orthogonal::place_dead_end_tiers`'s own doc has the rule and the reference it comes from).
///
/// A block whose members are all dead ends, fed only from nodes of one straight lane, hangs off
/// that lane instead of taking a rank of its own: every member sits at its own first source's
/// **flow** coordinate, so that edge is a straight, zero-bend run across the flow, and the whole
/// shelf sits clear of the lane on one side of it.
///
/// `docs/render-check/zz-design-2b-browser.png` draws `メタデータ DB` directly under `API ゲート`
/// and `成果物保管` directly under `ジョブ実行系`; `2c` is the same rotated, the shelf to the
/// right. Before this rule the block took the rank after everything that fed it and all three of
/// its edges were long multi-bend runs back across the picture (measured: `API -> DB` 1 bend over
/// 714px of horizontal run, `W -> DB` 3 bends, `W -> AR` 2 bends).
///
/// Stated over the two design sources **and** the same shape reduced to a plain four-node chain in
/// both directions, so it cannot be passing by reading something particular to those pictures.
#[test]
fn orthogonal_a_dead_end_block_fed_from_one_lane_hangs_off_it_with_zero_bend_drops() {
if !text_metrics::fonts_available() {
return;
}
for (name, src, direction) in tier_cases() {
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{name}: {id} is in the fixture"))
};
let (block, drops) = if name.starts_with("zz-design") {
("S", vec![("API", "DB"), ("W", "AR")])
} else {
("T", vec![("A", "t1"), ("C", "t2")])
};
let lane_cross = super::cross_of(direction, node(drops[0].0));
for (source, member) in &drops {
let (s, m) = (node(source), node(member));
assert!(
(super::flow_of(direction, s) - super::flow_of(direction, m)).abs() < 0.5,
"{name}: {member} must sit at {source}'s own flow coordinate, not {:.2} against \
{:.2}",
super::flow_of(direction, m),
super::flow_of(direction, s)
);
let e = d
.edges
.iter()
.find(|e| e.from == *source && e.to == *member)
.unwrap_or_else(|| panic!("{name}: {source} -> {member} must be routed"));
assert_eq!(
e.points.len(),
2,
"{name}: {source} -> {member} must be one straight drop, not {:?}",
e.points
);
}
// Every member on the same side of the lane, and every one of them clear of it.
let side = (super::cross_of(direction, node(drops[0].1)) - lane_cross).signum();
for (source, member) in &drops {
let (s, m) = (node(source), node(member));
let gap = side * (super::cross_of(direction, m) - lane_cross)
- super::cross_extent_of(direction, m)
- super::cross_extent_of(direction, s);
assert!(
gap >= super::ORTHO_NODE_SEP - 0.01,
"{name}: {member} sits {gap:.2}px clear of the lane, less than one \
{}px separation",
super::ORTHO_NODE_SEP
);
}
// The shelf's own frame holds its members and nothing outside it overlaps them.
let frame = d
.cluster(block)
.unwrap_or_else(|| panic!("{name}: {block} is drawn"));
let (fl, ft, fr, fb) = frame.bounds();
for (_, member) in &drops {
let (ml, mt, mr, mb) = node(member).bounds();
assert!(
ml >= fl && mt >= ft && mr <= fr && mb <= fb,
"{name}: {block}'s frame {:?} must hold {member} {:?}",
frame.bounds(),
node(member).bounds()
);
}
let members: Vec<&str> = drops.iter().map(|(_, m)| *m).collect();
for m in &members {
let (ml, mt, mr, mb) = node(m).bounds();
for other in &d.nodes {
if members.contains(&other.id.as_str()) {
continue;
}
let (ol, ot, or, ob) = other.bounds();
assert!(
ml >= or || or <= ol || mr <= ol || mb <= ot || mt >= ob,
"{name}: the tier member {m} {:?} overlaps {} {:?}",
node(m).bounds(),
other.id,
other.bounds()
);
let _ = (mt, ot, ob, ol, or);
}
}
}
}
/// The tier rule's own scope, stated as the two things that stop it firing — both of them
/// consequences of what a tier *is* rather than extra conditions bolted on:
///
/// 1. **a member that is not a dead end**: the block is a stage of the flow, not a shelf beside
/// it, so it keeps its own rank;
/// 2. **only one source**: a block fed from a single lane node already has a natural column (the
/// rank after that node) and §10-3's own fan machinery already places it there with one bend.
/// The rule exists for a group fed from *several* points along the lane, which no single rank
/// can serve without long runs.
/// 3. **the lane runs through a member**: a shelf hangs *off* the spine and cannot also *be* part
/// of it — hanging the block off the side would take the trunk's own next node with it.
/// `zz-design-2b`/`2c`'s own `外部` is this case (`コード置き場` is the spine's last node), which
/// is why that block keeps a rank of its own while `保存層` does not.
/// 4. **a member whose only input is an aside**: an aside carries no ordering vote anywhere else
/// in this pipeline (`EdgeLabel::rank_only`, weight `0`) and is drawn on the perimeter rather
/// than as a drop, so it is not something a member can be placed under. `zz-design-2b`'s own
/// `決済ページ` is this case.
///
/// All four are stated the same way — the member does **not** end up at its source's own flow
/// coordinate, which is the one thing a tier would guarantee.
#[test]
fn orthogonal_a_block_that_is_not_a_shelf_is_never_made_a_tier() {
if !text_metrics::fonts_available() {
return;
}
let cases = [
(
"a member with an out-edge",
"flowchart LR\n A --> B\n B --> C\n C --> E\n subgraph T[store]\n t1\n t2\n \
end\n A --> t1\n C --> t2\n t2 --> E",
"A",
"t1",
),
(
"one source only",
"flowchart LR\n A --> B\n B --> C\n C --> E\n subgraph T[store]\n t1\n t2\n \
end\n A --> t1\n A --> t2",
"A",
"t1",
),
(
// A back edge is still an out-edge, and it is the form that reaches this test on its
// own merits: an ordinary forward out-edge usually makes the member a lane node too,
// so condition 3 would have caught the block anyway and this one would never be read.
"a member with a back edge out of it",
"flowchart LR\n A --> B\n B --> C\n C --> E\n E --> F\n subgraph T[store]\n \
t1\n t2\n end\n A --> t1\n C --> t2\n t2 --> B",
"A",
"t1",
),
(
"the lane runs through a member",
"flowchart LR\n A --> B\n B --> t1\n subgraph T[store]\n t1\n t2\n end\n \
A --> t2",
"A",
"t2",
),
(
"a member fed only by an aside",
"flowchart LR\n A --> B\n B --> C\n C --> E\n subgraph T[store]\n t1\n t2\n \
end\n A --> t1\n C -.-> t2",
"A",
"t1",
),
];
for (why, src, source, member) in cases {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{why}: {id} is in the fixture"))
};
assert!(
(node(source).center.x - node(member).center.x).abs() > 0.5,
"{why}: {member} must keep a column of its own, not sit in {source}'s at x={:.2}",
node(member).center.x
);
if why == "the lane runs through a member" {
assert!(
(node("t1").center.y - node("A").center.y).abs() < 0.5,
"{why}: the trunk's own next node must stay on the lane, not be hung off it at \
y={:.2} against the lane's {:.2}",
node("t1").center.y,
node("A").center.y
);
}
}
}
/// Which side of the lane a tier takes: the one carrying **fewer other units** over the stretch of
/// lane it hangs off, positive (`LR` below / `TB` right) when the two tie —
/// `place_dead_end_tiers`'s own doc.
///
/// The design references are both the tie case (nothing else sits beside that stretch of their
/// spine at all), so the *other* branch needs a source of its own: one dead-end branch hanging
/// below the lane inside the tier's own span pushes the shelf to the other side.
#[test]
fn orthogonal_a_tier_takes_the_emptier_side_of_its_lane() {
if !text_metrics::fonts_available() {
return;
}
let src = "flowchart LR\n A --> B\n B --> C\n C --> E\n E --> F\n B --> X\n \
subgraph T[store]\n t1\n t2\n end\n A --> t1\n C --> t2";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{id} is in the fixture"))
};
let lane = node("A").center.y;
assert!(
node("X").center.y > lane,
"the fixture only means anything with X below the lane: {:.2} vs {lane:.2}",
node("X").center.y
);
for m in ["t1", "t2"] {
assert!(
node(m).center.y < lane,
"{m} must take the side away from X, not sit at {:.2} beside it (lane {lane:.2})",
node(m).center.y
);
}
// …and it is still a tier: each member under its own source, zero bends.
for (s, m) in [("A", "t1"), ("C", "t2")] {
assert!(
(node(s).center.x - node(m).center.x).abs() < 0.5,
"{m} must still sit in {s}'s own column"
);
}
}
/// The tier's own "nothing on this side may overlap it" half, stated directly on
/// [`orthogonal::place_dead_end_tiers`] rather than through a whole diagram: an end-to-end fixture
/// cannot hold *both* sides of a lane occupied without also disturbing the lane itself (measured —
/// every attempt to give the lane a second branch either flipped the side or bent the lane, which
/// then correctly stops the rule firing at all), and the push is exactly the part those fixtures
/// therefore never reach.
///
/// One unit above the lane and one below, both inside the tier's own flow span: the sides tie, the
/// shelf takes the positive one, and it has to clear the occupant there by [`super::ORTHO_NODE_SEP`]
/// rather than landing on it.
#[test]
fn orthogonal_a_tier_is_pushed_past_whatever_already_occupies_its_band() {
if !text_metrics::fonts_available() {
return;
}
use crate::preview::mermaid::flowchart::Direction;
let mut nodes = vec![
placed_node("A", 100.0, 100.0, 60.0, 40.0),
placed_node("B", 300.0, 100.0, 60.0, 40.0),
placed_node("C", 500.0, 100.0, 60.0, 40.0),
placed_node("X", 300.0, 200.0, 60.0, 40.0),
placed_node("Y", 300.0, 20.0, 60.0, 40.0),
placed_node("t1", 700.0, 100.0, 60.0, 40.0),
placed_node("t2", 700.0, 160.0, 60.0, 40.0),
];
let blocks = vec![super::SpecBlock {
id: "T".to_string(),
title: String::new(),
members: vec!["t1".to_string(), "t2".to_string()],
dashed: false,
}];
let ids: HashSet<String> = nodes.iter().map(|n| n.id.clone()).collect();
let tree = clusters::Tree::from_blocks(&blocks, |id| ids.contains(id));
let units = orthogonal::LaneUnits::build(&tree, &nodes);
let chain_next: HashMap<String, String> = [("A", "B"), ("B", "C")]
.into_iter()
.map(|(a, b)| (a.to_string(), b.to_string()))
.collect();
let edges: Vec<(String, String, bool)> = [
("A", "B"),
("B", "C"),
("B", "X"),
("B", "Y"),
("A", "t1"),
("C", "t2"),
]
.into_iter()
.map(|(a, b)| (a.to_string(), b.to_string(), false))
.collect();
let tiers = orthogonal::place_dead_end_tiers(
Direction::LeftToRight,
&mut nodes,
&tree,
&units,
&chain_next,
&edges,
);
assert_eq!(
tiers.len(),
1,
"the block must be recognised as one tier: {tiers:?}"
);
assert_eq!(tiers[0].side, 1.0, "the tie must take the positive side");
let at = |id: &str| -> &PlacedNode { nodes.iter().find(|n| n.id == id).expect(id) };
assert!(
(at("t1").center.x - 100.0).abs() < 1e-6 && (at("t2").center.x - 500.0).abs() < 1e-6,
"each member sits in its own first source's column: {:?}",
nodes
.iter()
.map(|n| (n.id.as_str(), n.center.x, n.center.y))
.collect::<Vec<_>>()
);
// X's own far edge is 220; a frame pad of `clusters::PAD` sits between the shelf's edge and
// its members, so the nearest member's own top edge is 220 + ORTHO_NODE_SEP + PAD.
let want = 220.0 + super::ORTHO_NODE_SEP + clusters::PAD + 20.0;
for m in ["t1", "t2"] {
assert!(
(at(m).center.y - want).abs() < 1e-6,
"{m} must clear X by one {}px separation plus the frame's own pad: {:.2}, want \
{want:.2}",
super::ORTHO_NODE_SEP,
at(m).center.y
);
}
}
/// "One **straight** lane" is a geometric fact, not only a selection: the sources have to have
/// actually ended up on one shared cross coordinate. A chain member can be pushed off its own
/// chain average by `align_straight_lanes`'s own overlap sweep (that function's own doc on why its
/// selection and its geometry can disagree), and a shelf hung off a lane that is not straight has
/// no single coordinate to hang from — so the rule stands down and the block keeps its rank.
///
/// Stated directly on [`orthogonal::place_dead_end_tiers`], for the same reason the outward-push
/// test above is: an end-to-end source whose chain the sweep actually bends is not something a
/// fixture can ask for on demand.
#[test]
fn orthogonal_a_tier_needs_its_sources_on_one_straight_lane() {
if !text_metrics::fonts_available() {
return;
}
use crate::preview::mermaid::flowchart::Direction;
let build = |c_cross: f64| -> Vec<PlacedNode> {
vec![
placed_node("A", 100.0, 100.0, 60.0, 40.0),
placed_node("B", 300.0, 100.0, 60.0, 40.0),
placed_node("C", 500.0, c_cross, 60.0, 40.0),
placed_node("t1", 700.0, 100.0, 60.0, 40.0),
placed_node("t2", 700.0, 160.0, 60.0, 40.0),
]
};
let blocks = vec![super::SpecBlock {
id: "T".to_string(),
title: String::new(),
members: vec!["t1".to_string(), "t2".to_string()],
dashed: false,
}];
let chain_next: HashMap<String, String> = [("A", "B"), ("B", "C")]
.into_iter()
.map(|(a, b)| (a.to_string(), b.to_string()))
.collect();
let edges: Vec<(String, String, bool)> = [("A", "B"), ("B", "C"), ("A", "t1"), ("C", "t2")]
.into_iter()
.map(|(a, b)| (a.to_string(), b.to_string(), false))
.collect();
for (why, c_cross, want) in [("straight", 100.0, 1), ("bent", 140.0, 0)] {
let mut nodes = build(c_cross);
let ids: HashSet<String> = nodes.iter().map(|n| n.id.clone()).collect();
let tree = clusters::Tree::from_blocks(&blocks, |id| ids.contains(id));
let units = orthogonal::LaneUnits::build(&tree, &nodes);
let tiers = orthogonal::place_dead_end_tiers(
Direction::LeftToRight,
&mut nodes,
&tree,
&units,
&chain_next,
&edges,
);
assert_eq!(
tiers.len(),
want,
"a {why} lane must yield {want} tier(s), not {tiers:?}"
);
}
}
/// §10-5 round 5's own label rule and §10-3 item 10's own merge mirror, both stated where they
/// were reported: the three-way merge into `API ゲート`.
///
/// The label half. `HTTPS` is a wide plate (~54px) on the middle sibling. Placed on that sibling's
/// *entry leg* — inside a corridor where §10-1 item 1 puts the three ports 16px apart — it covers
/// its two neighbours' legs, and `avoid_label_plates` then pushed their ports out from under it,
/// past each other, inverting item 1's own "もう一方の端点のcross座標順" and guaranteeing a crossing
/// (measured before the fix: `CLI`'s port stepped over *two* siblings). Two changes remove it —
/// the plate is chosen on a clear segment (`orthogonal::label_slot_clear`) and the nudge never
/// steps over a sibling (`orthogonal::push_outward`'s own doc).
///
/// The merge half (`docs/render-check/zz-design-2b-browser.png`, read against this output). The
/// three clients are a **pure merge** and none of them carries a through-lane, so
/// `orthogonal::merge_trunk_index`'s median clause picks the middle of the three *in declaration
/// order* — `UI`, exactly the source the design draws level with `API ゲート` — and `CLI` (above)
/// and `EX` (below) come in on the `±PORT_SPACING` ports either side of it. `align_straight_lanes`'s
/// own "タイは上・左優先" greedy used to hand the lane to `CLI`, the first-declared, which bent both
/// of the others in from the same side and grew `API ゲート` to 80px tall to fit three ports below
/// its own centre; `docs/STATUS.md`'s own ★未修正 entry reported it as the defect it is.
///
/// What this states, rather than either mechanism: three ports one `PORT_SPACING` apart in
/// **source order**, `UI`'s own edge dead straight while its two siblings each take the two bends
/// §10-1 item 1 allows a port-displaced edge ("退避則適用時は2回まで" — the design draws the same
/// out-across-in shape), and no two of the three crossing.
#[test]
fn orthogonal_design_2b_2c_the_merge_into_the_gate_keeps_its_port_order() {
if !text_metrics::fonts_available() {
return;
}
for (name, src, direction) in tier_cases()
.into_iter()
.filter(|(n, _, _)| n.starts_with("zz-design"))
{
let d = laid_out_flow(&src, "basis", "konoma-orthogonal");
let legs: Vec<(&str, &PlacedEdge)> = ["CLI", "UI", "EX"]
.iter()
.map(|from| {
(
*from,
d.edges
.iter()
.find(|e| e.from == *from && e.to == "API")
.unwrap_or_else(|| panic!("{name}: {from} -> API must be routed")),
)
})
.collect();
// The port coordinate on `API`'s own flow-axis face runs along the cross axis (`LR`'s
// Left face varies in y, `TB`'s Top face in x), so this is the same reading in both.
let ports: Vec<f64> = legs
.iter()
.map(|(_, e)| match direction {
crate::preview::mermaid::flowchart::Direction::TopToBottom
| crate::preview::mermaid::flowchart::Direction::BottomToTop => {
e.points[e.points.len() - 1].x
}
_ => e.points[e.points.len() - 1].y,
})
.collect();
// Evenly spaced, ascending in source order, and a whole number of `PORT_SPACING` slots
// apart — not necessarily *one* slot. §10-1 item 1 puts the grid at 16px, and §10-7's own
// label rule is allowed to step a port one slot further out when a plate is in its way, so
// long as it never steps over a sibling (`orthogonal::push_outward`). Both design
// directions exercise one of those two cases: `2b`/`LR` takes one slot each side, while
// `2c`/`TB` takes two, because there the `HTTPS` plate sits centred on the trunk's own
// vertical line at exactly the `y` both siblings' cross legs run along (measured: plate
// 360.7..414.6, the two legs stopping at 355.7 and 419.7). Pinning "exactly one slot"
// would be pinning which direction the plate happens to land in, not the rule.
let steps: Vec<f64> = ports.windows(2).map(|w| w[1] - w[0]).collect();
for (i, &step) in steps.iter().enumerate() {
let slots = (step / orthogonal::PORT_SPACING).round();
assert!(
slots >= 1.0 && (step - slots * orthogonal::PORT_SPACING).abs() < 0.01,
"{name}: the merge's ports must be a whole ascending {}px step apart in source \
order (CLI, UI, EX), not {ports:?} — {} then {}",
orthogonal::PORT_SPACING,
legs[i].0,
legs[i + 1].0
);
}
assert!(
(steps[0] - steps[1]).abs() < 0.01,
"{name}: the two siblings straddle the trunk's own port symmetrically: {ports:?}"
);
let ui = legs[1].1;
assert_eq!(
ui.points.len(),
2,
"{name}: UI -> API is the merge's own trunk (the median source in declaration order) \
and must be dead straight: {:?}",
ui.points
);
let api = d.node("API").expect("API ゲート must exist");
let api_cross = match direction {
crate::preview::mermaid::flowchart::Direction::TopToBottom
| crate::preview::mermaid::flowchart::Direction::BottomToTop => api.center.x,
_ => api.center.y,
};
assert!(
(ports[1] - api_cross).abs() < 0.01,
"{name}: the trunk enters on API's own centre port, so its two siblings straddle it: \
{ports:?} vs {api_cross}"
);
for (from, leg) in [legs[0], legs[2]] {
assert_eq!(
leg.points.len(),
4,
"{name}: {from} -> API is port-displaced, so §10-1 item 1 gives it two bends — out \
of its own face, across, and in: {:?}",
leg.points
);
}
for (i, (from_a, a)) in legs.iter().enumerate() {
for (from_b, b) in legs.iter().skip(i + 1) {
let crossing = a.points.windows(2).find_map(|wa| {
b.points
.windows(2)
.find_map(|wb| orthogonal::segment_crossing(wa, wb))
});
assert!(
crossing.is_none(),
"{name}: {from_a} -> API crosses {from_b} -> API at {crossing:?}: {:?} vs {:?}",
a.points,
b.points
);
}
}
}
}
#[test]
fn orthogonal_design_2b_2c_spine_runs_straight_through_the_sandbox() {
if !text_metrics::fonts_available() {
return;
}
// `2b`/`2c` by name: `2a` is a different graph, and `5b` (§10-8's own sizing artboard) is a
// third — this test is about one specific spine in one specific pair of pictures.
for (name, src) in orthogonal_design_reference_corpus()
.into_iter()
.filter(|(n, _)| *n == "zz-design-2b" || *n == "zz-design-2c")
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for (from, to) in [("API", "Q"), ("Q", "W"), ("W", "SB"), ("SB", "GIT")] {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == to)
.unwrap_or_else(|| panic!("{name}: {from}->{to} must exist"));
assert_eq!(
e.points.len(),
2,
"{name}: {from}->{to} is a spine segment — a straight 2-point line: {:?}",
e.points
);
}
// The two stores sit together, entirely to one side of the spine's own lane.
let cross = |id: &str| {
let n = d
.node(id)
.unwrap_or_else(|| panic!("{name}: {id} must exist"));
match name {
"zz-design-2b" => (n.center.y, n.size.h),
_ => (n.center.x, n.size.w),
}
};
let (lane, span) = cross("SB");
for store in ["DB", "AR"] {
let (c, store_span) = cross(store);
assert!(
(c - lane).abs() > (span + store_span) / 2.0,
"{name}: {store} (at {c:.1}) must fan clear of the spine's own lane ({lane:.1})"
);
}
let ((db, _), (ar, _)) = (cross("DB"), cross("AR"));
assert_eq!(
db < lane,
ar < lane,
"{name}: both 保存層 members belong on the same side of the spine — DB at {db:.1}, AR \
at {ar:.1}, lane at {lane:.1}"
);
}
}
/// The same shape as the fixture above, hand-built and minimal: a branching node whose only
/// continuing branch leads *out of* the frame its dead-end siblings are in.
///
/// `C` continues (into `F`, which is a member of a *different* frame, so the branch that carries the
/// diagram on is one that crosses a cluster boundary — `zz-design-2c`'s own `解析サンドボックス →
/// コード置き場` in miniature), `D` and `E` do not and are the members of `store`. The trunk has to be
/// `C`, the trunk edge has to be straight, and `C` — which does not belong to `store` — must not be
/// laid out *between* `D` and `E`, because a frame is derived from wherever its members sit and `C`
/// would then be inside a frame it has nothing to do with.
#[test]
fn orthogonal_fan_keeps_a_frames_members_together_and_the_trunk_outside_it() {
let src = "flowchart TB\n A --> B\n B --> C\n B --> D\n B --> E\n C --> F\n \
subgraph S[store]\n D\n E\n end\n subgraph T[out]\n F\n end\n";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let bc = d
.edges
.iter()
.find(|e| e.from == "B" && e.to == "C")
.expect("B->C must exist");
assert_eq!(
bc.points.len(),
2,
"B->C is the trunk (C is the only branch that continues) — a straight line: {:?}",
bc.points
);
let x = |id: &str| {
d.node(id)
.unwrap_or_else(|| panic!("{id} must exist"))
.center
.x
};
assert_eq!(
x("D") < x("C"),
x("E") < x("C"),
"store's two members belong on the same side of C, which is not one of them: D={}, E={}, \
C={}",
x("D"),
x("E"),
x("C")
);
let frame = d.cluster("S").expect("the store frame must be placed");
let (left, right) = (
frame.center.x - frame.size.w / 2.0,
frame.center.x + frame.size.w / 2.0,
);
let c = d.node("C").expect("C must exist");
assert!(
c.center.x + c.size.w / 2.0 < left || c.center.x - c.size.w / 2.0 > right,
"C is not a member of store, so its box must sit clear of that frame ({left:.1}..{right:.1}): \
C at {:.1} wide {:.1}",
c.center.x,
c.size.w
);
}
/// [`super::fan_split`]'s own two-branch case again, this time with the branches *disagreeing*: the
/// dead end takes the positive cross side even when it was declared first, so the trunk still sits
/// on the continuity boundary rather than wherever declaration order left it.
///
/// `A` is written before `B` and neither carries a class, so the colour grouping hands `rest` over
/// as `[A, B]` — dead end first. Without the stable partition [`super::fan_split`] runs, the centre
/// split would put `A` *above* the trunk and the continuing `B` below it; with it, `A` is last. The
/// assertion is on `A` alone rather than on the whole order, because `T` and `B` both continue and
/// the trunk pick between two equally-continuing branches is `align_straight_lanes`'s own
/// coordinate tie-break, not this rule's — whichever of them wins, the dead end belongs after it.
#[test]
fn orthogonal_three_way_fan_orders_the_continuing_branch_ahead_of_the_dead_end() {
let src = "flowchart LR\n S --> A\n S --> T\n T --> D\n S --> B\n B --> Q\n";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let y = |id: &str| {
d.node(id)
.unwrap_or_else(|| panic!("{id} must exist"))
.center
.y
};
assert!(
y("A") > y("T") && y("A") > y("B"),
"A is the fan's only dead end, so it sits below both continuing branches however they were \
declared: A.y={}, T.y={}, B.y={}",
y("A"),
y("T"),
y("B")
);
}
/// §10-3 item 2's own outside-in nesting (`3a`'s reference geometry, `orthogonal::route_fan_lane`'s
/// own doc), stated as the invariant it exists to buy: **no two fan-lane siblings on the same
/// source face ever cross each other's own segments** — not just "no node gets pierced" (the
/// pre-existing corpus invariants), a stronger, edge-vs-edge geometric claim only this fan region
/// can violate (an ordinary branch/merge pair never shares a face with more than one sibling).
///
/// Before the outside-in correction, the plain "step scales with distance from centre" formula drew
/// the *opposite* nesting: a sibling closer to the face's own centre got the *shallower* bend, so
/// its short stub sat inside a farther-out sibling's own bend lane and vice versa — on this exact
/// fixture (`設定のルール`'s ten-way fanout), `ページ描画`(`PD`, one step in from the centre on the
/// five-member half) and `一覧`(`AR`, two steps out) crossed: `AR`'s stub (`y=345.7`,
/// `x∈[319.75,359.75]`) sat inside the y-range of `PD`'s own vertical run (`y∈[308.3,361.7]`) at an
/// x (`327.75` under the old formula) still short of `PD`'s own bend depth — a real crossing, not a
/// hypothetical one, confirmed by hand against a dump of the pre-fix route before this test was
/// written. §10-3 item 5's "主辺どうしの交差は水平側が譲る" then fired on it, cutting a
/// [`orthogonal::CROSSING_GAP`]-px notch out of the horizontal stub — the "ファン根元のスタブが細切
/// れになる" symptom the user reported (`設定のルール` reads far busier than `3a`'s own reference).
/// The second half of this test (`gaps.is_empty()`) pins that the fix removes the crossing itself,
/// not just its visual symptom: once no two siblings cross, rule 5 never has anything to cut here.
#[test]
fn orthogonal_settings_rules_sample_fan_lane_siblings_never_cross() {
let src = SETTINGS_RULES_SAMPLE;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let fan: Vec<&PlacedEdge> = d.edges.iter().filter(|e| e.from == "C").collect();
assert_eq!(
fan.len(),
10,
"設定のルール's own ten-way fanout must still have all ten children: {:?}",
fan.iter().map(|e| e.to.as_str()).collect::<Vec<_>>()
);
for e in &fan {
assert!(
e.gaps.is_empty(),
"C->{}: a fan-lane sibling's own stub must never be cut by rule 5's crossing gap \
(that only fires when two siblings actually cross) — gaps: {:?}, points: {:?}",
e.to,
e.gaps,
e.points
);
}
for i in 0..fan.len() {
for j in (i + 1)..fan.len() {
let (a, b) = (fan[i], fan[j]);
for wa in a.points.windows(2) {
for wb in b.points.windows(2) {
assert!(
orthogonal::segment_crossing(wa, wb).is_none(),
"C->{} crosses C->{}'s own segment ({:?}-{:?} vs {:?}-{:?}) — the two fan \
siblings' own routes must never cross: {} points={:?}, {} points={:?}",
a.to,
b.to,
wa[0],
wa[1],
wb[0],
wb[1],
a.to,
a.points,
b.to,
b.points
);
}
}
}
}
}
/// A minimal synthetic fixture with the same shape as [`orthogonal_settings_rules_sample_fan_lane_
/// siblings_never_cross`]'s own real-diagram pin, deliberately unbalanced (5 above the trunk, 4
/// below — `3a`'s own five-vs-four split, `MD` landing dead on `C`'s own centre line as the tenth,
/// aligned member) rather than a tidy symmetric fan, so this still exercises the "nest against the
/// *larger* half's own outer rank" rule (the per-face loop in `evict` builds this, `Eviction::
/// fan_step`'s own doc) a perfectly even fixture never would — the two closest-to-centre siblings on
/// *either* side of an unbalanced face (`MD` above, `B1` below) must bend to the identical depth,
/// the same "306 と 338 が同じ 348 を使う" behaviour `3a`'s own reference shows.
///
/// Every out-edge carries a label (`|ラベルA1|` etc): §10-1 item 3's own minimum-segment-length rule
/// is what gives real diagrams the flow-axis room a deep nested bend needs (`3a`'s own `設定のルー
/// ル`'s ten-way fanout has labels on every edge too) — without one, `C`'s ten unlabelled leaf
/// children all land at the bare `RANK_SEP` (50px) away, too close for the busiest half's deepest
/// bend (`PORT_CLEARANCE * (5 + 1)` = 48px) to clear before reaching the target, which trips
/// `route_fan_lane`'s own defensive "past the target" guard into its plain-midpoint fallback —
/// a real, if narrow, gap in that fallback's own no-crossing guarantee (`route_fan_lane`'s own doc:
/// the fallback is not built with §10-3's nesting in mind at all), but a different, already-
/// documented limitation from the one this test exists to pin, so the fixture is built to stay clear
/// of it rather than conflate the two.
#[test]
fn orthogonal_synthetic_ten_way_fan_lane_siblings_never_cross() {
let src = "flowchart LR\n Z --> C{cond}\n \
C -->|ラベルA1| A1\n C -->|ラベルA2| A2\n C -->|ラベルA3| A3\n \
C -->|ラベルA4| A4\n C -->|ラベルA5| A5\n \
C -->|ラベルMD| MD\n \
C -->|ラベルB1| B1\n C -->|ラベルB2| B2\n C -->|ラベルB3| B3\n C -->|ラベルB4| B4";
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let fan: Vec<&PlacedEdge> = d.edges.iter().filter(|e| e.from == "C").collect();
assert_eq!(
fan.len(),
10,
"C's own ten-way fanout: {:?}",
fan.iter().map(|e| e.to.as_str()).collect::<Vec<_>>()
);
for e in &fan {
assert!(
e.gaps.is_empty(),
"C->{}: no fan-lane sibling may carry a crossing gap: {:?}",
e.to,
e.gaps
);
}
for i in 0..fan.len() {
for j in (i + 1)..fan.len() {
let (a, b) = (fan[i], fan[j]);
for wa in a.points.windows(2) {
for wb in b.points.windows(2) {
assert!(
orthogonal::segment_crossing(wa, wb).is_none(),
"C->{} crosses C->{}: {} points={:?}, {} points={:?}",
a.to,
b.to,
a.to,
a.points,
b.to,
b.points
);
}
}
}
}
}
// ---------------------------------------------------------------------------------------------
// 15. `konoma-orthogonal`'s own palette (`docs/FEATURE-MERMAID-RENDERER.md` §10-1 item 5)
//
// The mode carries its own colours: `Theme::for_routing` answers `theme::KONOMA` for
// `Routing::Orthogonal` whatever `[ui] mermaid_theme` says, exactly the way `[ui] mermaid_curve`
// is already inert there. Three things have to hold, and each is stated separately below so a
// failure names which one broke:
//
// 1. the mode really does draw the reference's own tokens (`konoma_orthogonal_draws_…`);
// 2. `[ui] mermaid_theme` cannot change a byte of it (`…_theme_is_inert_…`);
// 3. none of it leaks into `"splines"`, which is every diagram konoma draws by default
// (`…_palette_never_appears_under_splines`, plus the byte-exact hash sentinels below).
// ---------------------------------------------------------------------------------------------
/// FNV-1a over a string. A hand-rolled hash on purpose: `DefaultHasher` is explicitly not stable
/// across Rust releases, and a sentinel that changes when the toolchain does would be worse than
/// no sentinel at all.
pub(super) fn fnv1a(s: &str) -> u64 {
let mut h: u64 = 0xcbf2_9ce4_8422_2325;
for b in s.as_bytes() {
h ^= *b as u64;
h = h.wrapping_mul(0x0000_0100_0000_01b3);
}
h
}
/// **The five `[ui] mermaid_theme` values still draw, byte for byte (once numbers are masked),
/// what they drew before this mode had a palette of its own** — under `"splines"`, over every
/// design-reference source. (`konoma_orthogonal_theme_is_inert` below is the `"konoma-orthogonal"`
/// counterpart; it asserts the five themes agree with each other rather than pinning a hash,
/// because that mode's own drawing is still meant to change on purpose.)
///
/// The golden corpus (`snapshots/`) already pins the splines byte stream for `CORPUS`, but it
/// pins one theme (`dark`); this is the other half — every theme, on the three sources the design
/// work actually moves.
///
/// **The hashes are over [`mask_numbers`]' output, not the raw SVG.** The raw-byte pins (taken at
/// `cb799eb`) broke on Linux CI in 2026-09 (`zz-design-2a/dark/splines` and its siblings): the SVG
/// embeds text-measured coordinates (label widths, wrap points), and Linux's font metrics differ
/// from macOS's, so the raw bytes legitimately differ per platform even though the renderer drew
/// the right thing — the same class of failure v0.28.3 hit in the size-fitting math. Masking
/// numbers keeps the sentinel's actual purpose (the orthogonal work must not touch the splines
/// path: structure, element order, colours, theme attributes) without depending on which platform
/// measured the text. Retaken on this machine 2026-09-06; must never move except for the source
/// itself changing, which is what happened on 2026-09-04: `2b`/`2c` had mistranscribed the design
/// SVG's own dashed aside as `CLI -.->|リンク| PAY` when the SVG (read again at
/// `docs/render-check/zz-design-2b-wrap.html`'s `M48,298 …` / `2c-wrap.html`'s `M482,96 …`, both
/// starting at `ブラウザ UI`'s own rect, not `CLI`'s) draws it from `UI`.
#[test]
fn design_reference_renders_are_byte_stable_per_theme() {
if !text_metrics::fonts_available() {
return;
}
// (source, theme, routing, FNV-1a of the *number-masked* SVG — see `mask_numbers` — taken on
// this machine 2026-09-06). Masked, not raw: the raw-byte pins taken at `cb799eb` broke on
// Linux CI (`zz-design-2a/dark/splines` and friends) because the SVG embeds text-measured
// coordinates and Linux's font metrics differ from macOS's — the same class of failure v0.28.3
// hit in the size-fitting math. Masking numbers keeps this sentinel's actual purpose (the
// orthogonal work must not touch the splines path: structure, element order, colours, theme
// attributes) without depending on which platform measured the text.
let pinned: &[(&str, &str, &str, u64)] = &[
("zz-design-2a", "dark", "splines", 9110428218121198712),
("zz-design-2a", "light", "splines", 1747022079689348468),
("zz-design-2a", "classic", "splines", 17535052580463923218),
("zz-design-2a", "forest", "splines", 5950500633807246803),
("zz-design-2a", "neutral", "splines", 14524817129397963293),
("zz-design-2b", "dark", "splines", 6588218898948304090),
("zz-design-2b", "light", "splines", 14137538367644989869),
("zz-design-2b", "classic", "splines", 9166285881318630382),
("zz-design-2b", "forest", "splines", 14858083956717915971),
("zz-design-2b", "neutral", "splines", 12216959023177415803),
("zz-design-2c", "dark", "splines", 6588218898948304090),
("zz-design-2c", "light", "splines", 14137538367644989869),
("zz-design-2c", "classic", "splines", 9166285881318630382),
("zz-design-2c", "forest", "splines", 14858083956717915971),
("zz-design-2c", "neutral", "splines", 12216959023177415803),
];
let corpus = orthogonal_design_reference_corpus();
for (name, theme_name, routing, want) in pinned {
let (_, src) = corpus
.iter()
.find(|(n, _)| n == name)
.unwrap_or_else(|| panic!("{name} must still be in the design corpus"));
let svg = render_flow(src, theme_name, "basis", routing).expect("renders");
let masked = mask_numbers(&svg);
assert_eq!(
fnv1a(&masked),
*want,
"{name}/{theme_name}/{routing} is no longer byte-identical (number-masked) to its \
pinned render"
);
}
}
/// `[ui] mermaid_theme` is **inert** under `konoma-orthogonal`: all five values draw the same
/// bytes, because the mode answers the palette question itself ([`Theme::for_routing`]).
///
/// Asserted as "all five agree" *and* as "that agreed drawing is not what any of them draws under
/// splines", so a bug that made the mode fall back to `dark` — which would also make all five
/// agree — cannot pass.
#[test]
fn konoma_orthogonal_theme_is_inert() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_design_reference_corpus() {
let base = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("renders");
for theme_name in ["light", "modern", "classic", "mermaid", "forest", "neutral"] {
let other =
render_flow(src, theme_name, "basis", "konoma-orthogonal").expect("renders");
assert_eq!(
base, other,
"{name}: mermaid_theme={theme_name} changed a konoma-orthogonal render, which the \
mode is supposed to ignore entirely"
);
}
// Not vacuous: the agreed drawing really is the orthogonal palette and not a fallback to
// `dark`. `node_stroke` is the colour to ask about — every source here has at least one
// uncoloured node, and none of them writes that hex in a `classDef` of its own (unlike
// `node_fill`, which `2b`/`2c` do write).
assert!(
base.contains(theme::KONOMA.node_stroke),
"{name}: an orthogonal render must draw the palette's own outline colour: {base}"
);
let dark_splines = render_flow(src, "dark", "basis", "splines").expect("renders");
assert!(
!dark_splines.contains(theme::KONOMA.node_stroke),
"{name}: this comparison is only meaningful if the orthogonal palette is not simply \
the dark theme"
);
}
}
/// Nothing of the orthogonal palette reaches `"splines"` — the default every diagram konoma draws
/// is untouched. The complement of [`konoma_orthogonal_draws_the_design_reference_look`]: that one
/// says the colours are all there under orthogonal, this one says not one of them is there
/// without it.
#[test]
fn konoma_palette_never_appears_under_splines() {
if !text_metrics::fonts_available() {
return;
}
let palette = [
theme::KONOMA.background_ref,
theme::KONOMA.node_fill,
theme::KONOMA.node_stroke,
theme::KONOMA.node_text,
theme::KONOMA.cluster_stroke,
theme::KONOMA.cluster_text,
theme::KONOMA_TOKENS.composite_stroke,
theme::KONOMA_TOKENS.composite_rule,
];
for (name, src) in orthogonal_design_reference_corpus() {
for theme_name in ["dark", "light", "classic", "forest", "neutral"] {
let svg = render_flow(src, theme_name, "basis", "splines").expect("renders");
for colour in palette {
// `2a`/`2b`/`2c` write some of these hexes in their own `classDef`/`style`, and a
// source's own declaration is drawn under every routing — so what is checked is
// that the *palette* did not add one, not that the byte is absent.
let from_source = src.contains(colour);
assert!(
from_source || !svg.contains(colour),
"{name}/{theme_name} under splines drew {colour}, which only the orthogonal \
palette should ever produce"
);
}
}
}
}
/// **The design reference's own tokens, on the pictures the design drew** — every flowchart
/// design-reference source under `konoma-orthogonal`, checked against
/// `docs/render-check/zz-design-{2a,2b,2c}-wrap.html`.
///
/// One test rather than a dozen: each assertion below names its own token, and every one of them
/// is a property of the same render, so splitting them would mean re-rendering the corpus a dozen
/// times for no extra signal.
#[test]
fn konoma_orthogonal_draws_the_design_reference_look() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_design_reference_corpus() {
let svg = render_flow(src, "dark", "basis", "konoma-orthogonal").expect("renders");
// 1. No mermaid-palette colour survives anywhere: `dark`'s node fill, its outline, and its
// subgraph fill are the three that would show up first if the mode fell back.
for stale in ["#2b2b38", "#1f2020", "#cccccc", "#d3d3d3", "#8a8a8a"] {
assert!(
!svg.contains(stale),
"{name}: {stale} is a mermaid-theme colour and must not appear: {svg}"
);
}
// 2. Frames: no fill, 1px `#484f58`, dashed 4,3 — `zz-design-2a-wrap.html`'s own
// `<rect … fill="none" stroke="#484f58" stroke-width="1" stroke-dasharray="4,3">`.
for line in svg.lines() {
if !line.starts_with("<rect") || !line.contains("stroke=") {
continue;
}
if !line.contains("stroke=\"#484f58\"") {
continue;
}
assert!(
line.contains("fill=\"none\"")
&& line.contains("stroke-width=\"1\"")
&& line.contains("stroke-dasharray=\"4,3\"")
&& line.contains("rx=\"3\""),
"{name}: a subgraph frame must be an unfilled 1px 4,3-dashed rx=3 outline: {line}"
);
}
let frames = svg
.lines()
.filter(|l| l.starts_with("<rect") && l.contains("stroke=\"#484f58\""))
.count();
assert_eq!(
frames > 0,
src.contains("subgraph"),
"{name}: a source with a subgraph must draw a frame, and one without must not"
);
// 3. Nodes: `#161b22` (or a tint of the class colour), rx 3, 1.5px outline.
let node_rects: Vec<&str> = svg
.lines()
.filter(|l| l.starts_with("<rect") && l.contains("stroke-width=\"1.5\""))
.collect();
assert!(!node_rects.is_empty(), "{name}: no node rectangles at all");
for line in &node_rects {
assert!(
line.contains("rx=\"3\"") && line.contains("ry=\"3\""),
"{name}: a node box must have the reference's 3px corner: {line}"
);
let fill = attr(line, "fill").expect("a node rect has a fill");
assert!(
fill == theme::KONOMA.node_fill || fill.starts_with('#'),
"{name}: a node fill must be the palette's or a literal colour: {line}"
);
}
// 4. Text: the body at 14, an edge label at the reference's 11, a subgraph title at 12.
assert!(
svg.contains("font-size=\"14\""),
"{name}: body text must stay at the measured size: {svg}"
);
if svg.contains("<g class=\"edge-labels\">\n<") {
assert!(
svg.contains("font-size=\"11\""),
"{name}: an edge label must be drawn at the reference's 11px: {svg}"
);
}
assert_eq!(
svg.contains("font-size=\"12\""),
src.contains("subgraph"),
"{name}: a subgraph title is drawn at 12px, and a source with no subgraph draws none: \
{svg}"
);
// 5. "辺・矢尻・ラベル文字を同色で揃える": every edge's arrow head is filled with the
// line's own stroke, and its label is written in it too. Read straight out of the
// emitted markup, because that is where a mismatch would show.
let mut last_stroke: Option<&str> = None;
for line in svg.lines() {
if line.starts_with("<path") && line.contains("stroke=") {
last_stroke = attr(line, "stroke");
} else if line.starts_with("<polygon") && line.contains("fill=") {
let Some(stroke) = last_stroke else { continue };
// A node's own outline is a polygon too (a chamfered decision box); those carry a
// `stroke` of their own, an arrow head never does.
if line.contains("stroke=") {
continue;
}
assert_eq!(
attr(line, "fill"),
Some(stroke),
"{name}: an arrow head must be filled with its own line's colour: {line}"
);
}
}
// 6. A class-coloured node's outline is the class colour the source wrote, and the edge
// flowing into it is that colour one step lighter (§10-3 item 6) — so the two are
// always the same hue, which is what the reference's colour coding depends on.
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mut checked = 0;
for e in &d.edges {
let Some(target) = d.node(&e.to) else {
continue;
};
let Some(target_stroke) = target.style.as_ref().and_then(|s| s.stroke.as_deref())
else {
continue;
};
let Some(line) = e.style.as_ref().and_then(|s| s.stroke.as_deref()) else {
continue;
};
let Some(lightened) = super::style::lighten(target_stroke) else {
continue;
};
// Only when the source did not colour this edge itself — a `linkStyle` is the more
// specific instruction and wins over the derivation.
if src.contains("linkStyle") {
continue;
}
assert_eq!(
line, lightened,
"{name}: edge {}->{} must draw its target's own {target_stroke}, one step \
lighter",
e.from, e.to
);
checked += 1;
}
// Only a source that actually declares a class can have a class-coloured edge — `5b` is
// §10-8's sizing artboard and is deliberately monochrome, like the artboard it comes from.
if !src.contains("linkStyle") && src.contains("classDef") {
assert!(
checked > 0,
"{name}: no class-coloured edge was checked — the comparison is vacuous"
);
}
}
}
/// [`super::aside_weight`]'s own truth table, stated directly rather than only through the two
/// layout tests below: the zero weight is for an **author-dotted** edge under **`konoma-
/// orthogonal`** and nothing else. Every other stroke, and every stroke at all under
/// `Routing::Splines`, keeps `EdgeLabel`'s own default — which is what makes the default rendering
/// of every diagram kind byte-identical (§10-2) rather than merely "probably unchanged".
#[test]
fn orthogonal_only_a_dotted_edge_is_an_aside_for_dagre() {
let default = crate::preview::mermaid::layout::EdgeLabel::default().weight;
assert_eq!(
super::aside_weight(Routing::Orthogonal, Stroke::Dotted),
0,
"a dotted edge under konoma-orthogonal is the aside the perimeter lane is for"
);
for stroke in [
Stroke::Normal,
Stroke::Thick,
Stroke::Invisible,
Stroke::Invalid,
] {
assert_eq!(
super::aside_weight(Routing::Orthogonal, stroke),
default,
"{stroke:?} is not an aside — only the author's own dotted line marks one"
);
}
for stroke in [
Stroke::Normal,
Stroke::Thick,
Stroke::Dotted,
Stroke::Invisible,
Stroke::Invalid,
] {
assert_eq!(
super::aside_weight(Routing::Splines, stroke),
default,
"{stroke:?} under splines keeps dagre's own default weight"
);
}
}
/// The design rule [`super::aside_weight`] exists to state, checked on the finished layout rather
/// than on the weight it hands dagre: **an aside does not decide where the flow's own nodes go.**
///
/// Stated as "no two nodes that share a rank swap places when the aside is added" — the strongest
/// form that is actually true, and the one that names the user-visible defect. The defect was
/// found when `zz-design-2b`/`2c` were still mistranscribed as `CLI -.->|リンク| PAY` (`CLI` being
/// the client row's *first* declared sibling): with that aside weighted like a flow edge the three
/// clients came out `EX, UI, CLI` instead of `CLI, UI, EX`, so `CLI` ended up at the far side of
/// its own frame with its edge into `API ゲート` climbing back across `ブラウザ UI`'s. The corrected
/// source (`UI -.->|リンク| PAY` — `UI` is the *middle* sibling, verified against
/// `docs/render-check/zz-design-2b-wrap.html`'s own SVG) does not reproduce that reorder even
/// hypothetically weighted like a flow edge (re-measured after the fix: `CLI, UI, EX` either way,
/// on both `2b` and `2c`), which is exactly why the general shape still needs its own fixture —
/// see `orthogonal-dotted-aside-merge` below, kept independent of which sibling either design
/// reference happens to use. Nodes that do *not* share a rank are deliberately out of scope:
/// `zz-design-2c`'s own `ブラウザ UI` (rank 1) and `決済ページ` (rank 17) do trade places on the
/// cross axis, which is not a reordering of anything — they were never comparable.
///
/// The pair is built by deleting the one `-.->` line from each source, with the count asserted, so
/// the design-reference sources stay single-sourced and cannot drift away from the pictures in
/// `docs/render-check/`.
///
/// What this does **not** claim is that the two layouts are identical — only that no rank is
/// reordered. How *wide* a rank comes out is the second half of the same design rule and is stated
/// separately, by [`orthogonal_a_dotted_aside_leaves_its_source_stack_at_one_node_pitch`]: an aside
/// used to still span its ranks as a dummy chain, which `parentDummyChains` parents into the
/// source's own frame and which then has to sit outside every wider sibling frame, stretching the
/// frame until the position phase could spread its members (69.4px pitch without the aside,
/// 114.5/190.2px with it, measured on `2b` before `EdgeLabel::rank_only` existed).
#[test]
fn orthogonal_a_dotted_aside_does_not_reorder_a_rank() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
let design = orthogonal_design_reference_corpus();
let named = |name: &str| -> &'static str {
design
.iter()
.find(|(n, _)| *n == name)
.unwrap_or_else(|| panic!("{name} is in the design-reference corpus"))
.1
};
let cases: [(&str, &str, Direction); 3] = [
(
"orthogonal-dotted-aside-merge",
dotted_aside_merge_source(),
Direction::LeftToRight,
),
(
"zz-design-2b",
named("zz-design-2b"),
Direction::LeftToRight,
),
(
"zz-design-2c",
named("zz-design-2c"),
Direction::TopToBottom,
),
];
for (name, src, direction) in cases {
let kept: Vec<&str> = src.lines().filter(|l| !l.contains("-.->")).collect();
assert_eq!(
src.lines().count() - kept.len(),
1,
"{name}: the pair is built by deleting exactly one dotted line"
);
let without = laid_out_flow(&kept.join("\n"), "basis", "konoma-orthogonal");
let with = laid_out_flow(src, "basis", "konoma-orthogonal");
let cross: HashMap<&str, f64> = with
.nodes
.iter()
.map(|n| (n.id.as_str(), super::cross_of(direction, n)))
.collect();
let mut ranks: HashMap<i64, Vec<&PlacedNode>> = HashMap::new();
for n in &without.nodes {
// A rank is a shared flow-axis centre. Keyed off the aside-free layout, which is the
// one this rule measures the other against; both layouts agree on every flow-axis
// coordinate, so the grouping is the same either way.
ranks
.entry((super::flow_of(direction, n) * 100.0).round() as i64)
.or_default()
.push(n);
}
let mut checked = 0usize;
for members in ranks.values() {
if members.len() < 2 {
continue;
}
let mut order: Vec<&PlacedNode> = members.clone();
order.sort_by(|a, b| {
super::cross_of(direction, a)
.partial_cmp(&super::cross_of(direction, b))
.expect("a placed centre is never NaN")
});
for pair in order.windows(2) {
let (lo, hi) = (pair[0].id.as_str(), pair[1].id.as_str());
let (Some(&a), Some(&b)) = (cross.get(lo), cross.get(hi)) else {
continue;
};
assert!(
a < b,
"{name}: adding the aside swapped {lo} and {hi}, which share a rank — \
without it {lo} comes first, with it {lo} is at {a:.2} and {hi} at {b:.2}"
);
checked += 1;
}
}
assert!(
checked >= 2,
"{name}: no same-rank pair was compared — the check is vacuous"
);
}
}
/// The picture the rule above buys, on the cluster-free fixture where nothing else is in play
/// (`orthogonal-dotted-aside-merge`): the three merge siblings stay stacked one node pitch apart
/// in declaration order, and their three edges land on three distinct, evenly spaced ports of the
/// target's own entry face in that same order, none crossing another.
///
/// The pitch bound is the layout's own — the tallest of the three plus [`super::ORTHO_NODE_SEP`],
/// which is exactly what dagre's position phase leaves between two neighbours on one rank when
/// nothing pulls them apart. With the aside weighted like a flow edge `A` is dragged past `B`
/// instead (`orthogonal_a_dotted_aside_does_not_reorder_a_rank` states that half), so the port
/// order below is the half that says the *merge* still reads correctly afterwards.
#[test]
fn orthogonal_dotted_aside_leaves_its_merge_siblings_evenly_stacked() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
let d = laid_out_flow(dotted_aside_merge_source(), "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{id} is in the fixture"))
};
let sources = ["A", "B", "C"].map(node);
let pitch = sources.iter().map(|n| n.size.h).fold(0.0_f64, f64::max) + super::ORTHO_NODE_SEP;
for pair in sources.windows(2) {
let gap = super::cross_of(Direction::LeftToRight, pair[1])
- super::cross_of(Direction::LeftToRight, pair[0]);
assert!(
gap > 0.0 && gap <= pitch + 0.01,
"{} and {} are {gap:.2}px apart on the cross axis, more than one {pitch:.2}px \
node pitch — the merge siblings are no longer a stack",
pair[0].id,
pair[1].id
);
}
let merge = node("M");
let face = merge.center.x - merge.size.w / 2.0;
let mut ports: Vec<(&str, f64)> = Vec::new();
for from in ["A", "B", "C"] {
let e = d
.edges
.iter()
.find(|e| e.from == from && e.to == "M")
.unwrap_or_else(|| panic!("{from} -> M is in the fixture"));
let end = e.points.last().expect("a routed edge has points");
assert!(
(end.x - face).abs() <= orthogonal::PORT_INSET + 0.01,
"{from} -> M ends at x={:.2}, not on M's own left face at x={face:.2}",
end.x
);
ports.push((from, end.y));
}
for (i, (from, y)) in ports.iter().enumerate() {
for (other, other_y) in ports.iter().skip(i + 1) {
assert!(
(y - other_y).abs() >= orthogonal::PORT_SPACING - 0.01,
"{from} and {other} share a port on M's left face ({y:.2} vs {other_y:.2})"
);
}
}
assert!(
ports.windows(2).all(|p| p[0].1 < p[1].1),
"the ports on M's left face are not in the sources' own cross-axis order: {ports:?}"
);
let routed = |from: &str| -> &PlacedEdge {
d.edges
.iter()
.find(|e| e.from == from && e.to == "M")
.expect("checked above")
};
for (i, from) in ["A", "B", "C"].iter().enumerate() {
for other in ["A", "B", "C"].iter().skip(i + 1) {
assert!(
!orthogonal::polylines_cross(&routed(from).points, &routed(other).points),
"{from} -> M crosses {other} -> M"
);
}
}
}
/// §10-3 item 10's own hop nesting, stated as the ordering rule rather than only as "nothing
/// crossed" (`orthogonal_merge_sibling_hops_never_cross_or_coincide_across_corpus` states that
/// half): among merge siblings whose sources **share a rank**, the hop row nearest the target
/// belongs to the sibling whose hop leg has to travel furthest along the cross axis.
///
/// This is what `orthogonal::nest_merge_target_hops`'s own `Candidate::span` tie-break decides,
/// and it only ever has to decide it for a shared rank — siblings at different ranks are already
/// separated by `max_reach`, which the widest leg has no claim over (a nearer source with a wide
/// leg must still not be pushed past its own facing wall, `Candidate::max_reach`'s own doc). So
/// the invariant is scoped exactly the way the tie-break is, and reads the finished polylines
/// rather than any of that pass's internal numbers.
#[test]
fn orthogonal_merge_hops_from_one_rank_nest_widest_leg_first() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
let mut checked = 0usize;
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let direction = if src.contains("LR") || src.contains("RL") {
Direction::LeftToRight
} else {
Direction::TopToBottom
};
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let by_id: HashMap<&str, &PlacedNode> =
d.nodes.iter().map(|n| (n.id.as_str(), n)).collect();
let mut out_degree: HashMap<&str, usize> = HashMap::new();
for e in &d.edges {
*out_degree.entry(e.from.as_str()).or_insert(0) += 1;
}
let mut by_target: HashMap<&str, Vec<&PlacedEdge>> = HashMap::new();
for e in &d.edges {
// The same scope `orthogonal::is_merge_hop_candidate` itself has: a genuine merge
// sibling, drawn as the four-point "out, across, in" hop this rule is about.
if e.stroke == Stroke::Invisible
|| out_degree.get(e.from.as_str()).copied().unwrap_or(0) > 1
|| e.points.len() != 4
{
continue;
}
by_target.entry(e.to.as_str()).or_default().push(e);
}
for (target, merge) in by_target {
let Some(&target_node) = by_id.get(target) else {
continue;
};
// Flow-axis distance from the target's own centre out to the hop row, and cross-axis
// width of the leg that runs along it — both read straight off the polyline.
let leg = |e: &PlacedEdge| -> Option<(f64, f64, f64)> {
let src_flow = super::flow_of(direction, by_id.get(e.from.as_str())?);
let hop = &e.points[1];
let (hop_flow, hop_cross) = match direction {
Direction::TopToBottom | Direction::BottomToTop => (hop.y, hop.x),
Direction::LeftToRight | Direction::RightToLeft => (hop.x, hop.y),
};
let tgt_flow = super::flow_of(direction, target_node);
let span = (hop_cross
- match direction {
Direction::TopToBottom | Direction::BottomToTop => e.points[2].x,
Direction::LeftToRight | Direction::RightToLeft => e.points[2].y,
})
.abs();
Some((src_flow, (tgt_flow - hop_flow).abs(), span))
};
for i in 0..merge.len() {
for j in (i + 1)..merge.len() {
let (Some(a), Some(b)) = (leg(merge[i]), leg(merge[j])) else {
continue;
};
// Same rank only, and only when the two legs are genuinely different widths —
// two siblings whose legs match have nothing to nest.
if (a.0 - b.0).abs() > 0.01 || (a.2 - b.2).abs() <= 0.01 {
continue;
}
let (wide, narrow) = if a.2 > b.2 { (a, b) } else { (b, a) };
assert!(
wide.1 <= narrow.1 + 0.01,
"{name}: into {target}, the {:.2}px-wide hop leg sits {:.2}px from the \
target while the narrower {:.2}px leg sits {:.2}px — the wide leg has to \
be the one nearest the target or the two cross",
wide.2,
wide.1,
narrow.2,
narrow.1
);
checked += 1;
}
}
}
}
assert!(
checked > 0,
"no same-rank merge siblings with differing leg widths were compared — the check is vacuous"
);
}
// ---------------------------------------------------------------------------------------------
// §10-1 item 4, both halves: an aside constrains ranks and nothing else (`super::is_aside` /
// `EdgeLabel::rank_only`), and it is drawn on the outer perimeter lane whichever way it points
// (`orthogonal::classify`'s own `aside` branch).
// ---------------------------------------------------------------------------------------------
/// The four sources that carry an author-dotted aside, paired with the direction they are laid out
/// in and the merge stack the aside leaves from — the two synthetic fixtures
/// ([`orthogonal_only_corpus`]'s own `orthogonal-dotted-aside-merge` and its framed `TB` sibling)
/// and the two design references that produced the rule.
fn dotted_aside_cases() -> Vec<(
&'static str,
&'static str,
crate::preview::mermaid::flowchart::Direction,
[&'static str; 3],
)> {
use crate::preview::mermaid::flowchart::Direction;
let named = |list: Vec<(&'static str, &'static str)>, name: &str| -> &'static str {
list.iter()
.find(|(n, _)| *n == name)
.unwrap_or_else(|| panic!("{name} is in the corpus"))
.1
};
vec![
(
"orthogonal-dotted-aside-merge",
named(orthogonal_only_corpus(), "orthogonal-dotted-aside-merge"),
Direction::LeftToRight,
["A", "B", "C"],
),
(
"orthogonal-dotted-aside-merge-tb",
named(orthogonal_only_corpus(), "orthogonal-dotted-aside-merge-tb"),
Direction::TopToBottom,
["A", "B", "C"],
),
(
"zz-design-2b",
named(orthogonal_design_reference_corpus(), "zz-design-2b"),
Direction::LeftToRight,
["CLI", "UI", "EX"],
),
(
"zz-design-2c",
named(orthogonal_design_reference_corpus(), "zz-design-2c"),
Direction::TopToBottom,
["CLI", "UI", "EX"],
),
// A stack of three siblings all feeding one hub, with the aside leaving the **middle**
// one, so its way out of the row has to pass a sibling's leg on whichever side it takes.
// Added 2026-09-04 to keep the crossing-gap machinery covered by a two-line diagram of its
// own rather than by whichever design direction happened to reproduce a crossing that
// week; renamed 2026-09-05 (it used to be `…-crosses-a-sibling-leg-…`) because it no
// longer crosses one: with nothing feeding the row from the other side, the aside now
// leaves the row the *free* way and goes round, which is §10-0's own preference and what
// the crossing term added that day is for. It stays in the list as the case that states
// exactly that — a middle sibling's aside gets out without cutting anything — while
// `orthogonal-aside-must-cross-a-leg-lr` (`orthogonal_only_corpus`, the same shape with the
// row fed from both sides) carries the crossing the gap rule needs.
(
"orthogonal-aside-off-a-middle-sibling-lr",
"flowchart LR\n subgraph S[row]\n A\n B\n D\n end\n A --> H\n B --> H\n D --> H\n H --> Z\n B -.-> Z",
Direction::LeftToRight,
["A", "B", "D"],
),
(
"orthogonal-aside-off-a-middle-sibling-tb",
"flowchart TB\n subgraph S[row]\n A\n B\n D\n end\n A --> H\n B --> H\n D --> H\n H --> Z\n B -.-> Z",
Direction::TopToBottom,
["A", "B", "D"],
),
(
"orthogonal-aside-must-cross-a-leg-lr",
named(orthogonal_only_corpus(), "orthogonal-aside-must-cross-a-leg-lr"),
Direction::LeftToRight,
["A", "B", "D"],
),
]
}
/// §10-1 item 4's **layout** half, stated on the finished picture: a rank an aside leaves from is
/// no wider for the aside being there.
///
/// `super::aside_weight` (weight `0`) alone was not enough, and the gap it left is what this
/// states. An aside still spans its ranks, so — until `EdgeLabel::rank_only` — `normalize` built it
/// a dummy chain that occupied a lane in every rank in between; `parent_dummy_chains` parents a
/// dummy whose rank falls inside a cluster's own span into that cluster, that lane then has to sit
/// outside every wider sibling frame, and the frame it was parented into stretches to hold it,
/// which gives `position::bk` room to spread the members. Measured on `zz-design-2b`: the three
/// clients came out **114.5 and 190.2px** apart where one node pitch is 69.4.
///
/// The bound is the layout's own — the widest member's own cross-axis size plus
/// [`super::ORTHO_NODE_SEP`], which is what dagre's position phase leaves between two neighbours on
/// one rank when nothing pulls them apart — never a recorded coordinate, so this cannot pass by
/// being re-recorded. Runs over the framed fixtures as well as the plain one: the cluster-free
/// `orthogonal-dotted-aside-merge` already stacked correctly under weight `0` alone, so a test that
/// only saw it would have said the defect was fixed when it was not.
#[test]
fn orthogonal_a_dotted_aside_leaves_its_source_stack_at_one_node_pitch() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
for (name, src, direction, stack) in dotted_aside_cases() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{name}: {id} is in the fixture"))
};
let members = stack.map(node);
let cross_size = |n: &PlacedNode| match direction {
Direction::TopToBottom | Direction::BottomToTop => n.size.w,
Direction::LeftToRight | Direction::RightToLeft => n.size.h,
};
for pair in members.windows(2) {
// One pitch is the two neighbours' own half-sizes plus the separation dagre keeps
// between them; the widest member's full size is the same quantity rounded up, which
// is the form the pre-existing sibling test already uses.
let pitch = cross_size(pair[0]).max(cross_size(pair[1])) + super::ORTHO_NODE_SEP;
let gap = super::cross_of(direction, pair[1]) - super::cross_of(direction, pair[0]);
assert!(
gap > 0.0 && gap <= pitch + 0.01,
"{name}: {} and {} sit {gap:.2}px apart on the cross axis, more than one \
{pitch:.2}px node pitch — the aside is still spreading the rank it leaves",
pair[0].id,
pair[1].id
);
}
}
}
/// The half of §10-1 item 4's layout rule that says why the aside is lifted out **after** ranking
/// rather than never handed to dagre at all: a target nothing else reaches would otherwise have no
/// in-edge, and dagre's own ranking would put it at rank 0 — *upstream* of the source that links
/// to it (`super::aside_weight`'s own doc records the same measurement for the rejected "drop it
/// entirely" variant).
///
/// Stated on the flow axis of the finished picture rather than on a rank number, so it holds
/// whatever `pull_back_fan_ranks` afterwards does with the ranks: an aside's target is never
/// upstream of its source. `zz-design-2b`/`2c`'s own `決済ページ` is reached by the dotted
/// `UI -.->|リンク| PAY` and by nothing else at all, which is exactly the shape at issue; the
/// third case states it on a two-line diagram where nothing else could possibly be holding the
/// target in place.
#[test]
fn orthogonal_an_aside_only_target_still_ranks_after_its_source() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
let design = orthogonal_design_reference_corpus();
let named = |name: &str| -> &'static str {
design
.iter()
.find(|(n, _)| *n == name)
.unwrap_or_else(|| panic!("{name} is in the design-reference corpus"))
.1
};
let cases: [(&str, &str, Direction, &str, &str); 4] = [
(
"bare-lr",
"flowchart LR\n A --> B\n A -.-> D",
Direction::LeftToRight,
"A",
"D",
),
(
"bare-tb",
"flowchart TB\n A --> B\n A -.-> D",
Direction::TopToBottom,
"A",
"D",
),
(
"zz-design-2b",
named("zz-design-2b"),
Direction::LeftToRight,
"UI",
"PAY",
),
(
"zz-design-2c",
named("zz-design-2c"),
Direction::TopToBottom,
"UI",
"PAY",
),
];
for (name, src, direction, source, target) in cases {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let node = |id: &str| -> &PlacedNode {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{name}: {id} is in the fixture"))
};
let (s, t) = (
super::flow_of(direction, node(source)),
super::flow_of(direction, node(target)),
);
assert!(
t > s + 0.01,
"{name}: the aside's target {target} sits at flow {t:.2}, not downstream of its \
source {source} at {s:.2} — the aside stopped being a ranking constraint"
);
}
}
/// The content box every node and every frame of `d` fits in — what [`orthogonal::PERIMETER_MARGIN`]
/// is measured out from, recomputed here from the finished picture rather than asked of the router.
fn diagram_content_box(d: &Diagram) -> (f64, f64, f64, f64) {
let (mut l, mut t, mut r, mut b) = (f64::MAX, f64::MAX, f64::MIN, f64::MIN);
for (nl, nt, nr, nb) in d
.nodes
.iter()
.map(|n| n.bounds())
.chain(d.clusters.iter().map(|c| c.bounds()))
{
l = l.min(nl);
t = t.min(nt);
r = r.max(nr);
b = b.max(nb);
}
(l, t, r, b)
}
/// Whether `e` is one of the lines drawn **on the perimeter ring** — read off the finished picture:
/// the ring is [`orthogonal::PERIMETER_MARGIN`] px outside the content box, so a rider is exactly a
/// line with a vertex out there. A self-loop is excluded, the same way `orthogonal::routes_last`
/// excludes it: it is `reverse` but is drawn locally, and is main flow as far as anything crossing
/// it is concerned.
fn rides_the_ring(e: &PlacedEdge, (l, t, r, b): (f64, f64, f64, f64)) -> bool {
e.from != e.to
&& e.points.iter().any(|p| {
p.x <= l - orthogonal::PERIMETER_MARGIN + 0.01
|| p.y <= t - orthogonal::PERIMETER_MARGIN + 0.01
|| p.x >= r + orthogonal::PERIMETER_MARGIN - 0.01
|| p.y >= b + orthogonal::PERIMETER_MARGIN - 0.01
})
}
/// How many segments of `polylines` the line `pts` crosses, through the same
/// [`orthogonal::segment_crossing`] the router itself counts with (so a shared port or a
/// T-junction — a touch, not a crossing — is not one here either).
fn crossings_against(pts: &[Point], polylines: &[Vec<Point>]) -> usize {
pts.windows(2)
.map(|a| {
polylines
.iter()
.flat_map(|o| o.windows(2))
.filter(|b| orthogonal::segment_crossing(a, b).is_some())
.count()
})
.sum()
}
/// §10-1 item 4's **routing** half: "戻り辺・補助辺は破線で外周レーンを回す…外周レーンは最も外側の枠
/// から16px以上外に置く", as §10-5 round 5 narrowed it — an author-dotted edge whose direct route
/// would **cut through the picture** leaves the content box by at least
/// [`orthogonal::PERIMETER_MARGIN`] px somewhere along its run, and gets there in no more corners
/// than the design's own drawing of it uses; one with nothing at all between its two ends stays a
/// plain, local line instead.
///
/// Before item 4's routing half existed, [`orthogonal::route_perimeter`] was reached only by a
/// *reverse* edge, so a forward aside stayed on dagre's own waypoint chain and was drawn straight
/// through the middle of the picture the design takes round the outside — `zz-design-2b`'s own
/// `UI -.->|リンク| PAY` ran the full 1301px width of the diagram between two frames. The
/// narrowing is the opposite error, found on `CORPUS`'s own `strokes`: `B -.-> C`, two adjacent
/// boxes on one row with nothing between them, was sent round the outside and came back a two-bend
/// hop where a straight two-point line reaches (§10-0 — a rule is adopted if it makes lines
/// simpler).
///
/// Which of the two an aside is, is decided here from the finished picture — *is anything at all
/// inside the rectangle its two ends span* — rather than by asking the implementation
/// (`orthogonal::aside_route_stays_local`), so the two are independent statements of the same rule
/// rather than the implementation agreeing with itself. The content box is recomputed here from the
/// diagram's own nodes and frames for the same reason. Four bends is the design's own worst case
/// (`zz-design-2c`: down, along, down, in) — `2a` draws two and `2b` three.
#[test]
fn orthogonal_every_aside_rides_the_outer_perimeter_lane() {
if !text_metrics::fonts_available() {
return;
}
let mut checked = 0usize;
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let (l, t, r, b) = diagram_content_box(&d);
for e in &d.edges {
if e.stroke != Stroke::Dotted || e.from == e.to {
continue;
}
checked += 1;
let outside = rides_the_ring(e, (l, t, r, b));
// Is there anything at all between the two ends? Restated here from the finished
// picture: the rectangle the two boxes span, against every other node box and every
// frame that does not hold both of them.
let node_of = |id: &str| {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{name}: {id} is a node"))
};
let (sl, st, sr, sb) = node_of(&e.from).bounds();
let (tl, tt, tr, tb) = node_of(&e.to).bounds();
let span = (sl.min(tl), st.min(tt), sr.max(tr), sb.max(tb));
let clear = |(nl, nt, nr, nb): (f64, f64, f64, f64)| {
nl >= span.2 || nr <= span.0 || nt >= span.3 || nb <= span.1
};
let holds = |(fl, ft, fr, fb): (f64, f64, f64, f64), n: &PlacedNode| {
n.center.x >= fl && n.center.x <= fr && n.center.y >= ft && n.center.y <= fb
};
let nothing_between = d
.nodes
.iter()
.all(|n| n.id == e.from || n.id == e.to || clear(n.bounds()))
&& d.clusters.iter().all(|c| {
let bounds = c.bounds();
(holds(bounds, node_of(&e.from)) && holds(bounds, node_of(&e.to)))
|| clear(bounds)
});
if nothing_between {
assert!(
!outside && e.points.len() <= 3,
"{name}: the aside {}->{} has nothing between its two ends and must stay a \
plain local line, not take the perimeter: {:?}",
e.from,
e.to,
e.points
);
continue;
}
assert!(
outside,
"{name}: the aside {}->{} never reaches the perimeter lane — no vertex sits \
{}px outside the content box ({l:.2},{t:.2})-({r:.2},{b:.2}): {:?}",
e.from,
e.to,
orthogonal::PERIMETER_MARGIN,
e.points
);
let bends = e.points.len().saturating_sub(2);
assert!(
bends <= 4,
"{name}: the aside {}->{} takes {bends} corners to get round the outside, more \
than the design's own worst case of 4: {:?}",
e.from,
e.to,
e.points
);
}
}
assert!(
checked >= 5,
"only {checked} asides were checked — the corpus lost its dotted edges and the check is \
vacuous"
);
}
/// §10-1 item 4's own "跨ぐ側の線に12pxの隙間を開ける", for the newest member of the perimeter
/// family: where a **forward** aside crosses another edge, the aside is the side that is cut, and
/// exactly [`orthogonal::CROSSING_GAP`] px of its own arc length is left undrawn.
///
/// By arc length along the whole polyline, never straight-line distance between the gap's two
/// endpoints — `orthogonal_crossing_gaps_cut_the_horizontal_side_of_each_crossing`'s own doc has
/// the Linux-CI regression that distinction exists to catch.
#[test]
fn orthogonal_a_forward_aside_carries_the_crossing_gaps() {
if !text_metrics::fonts_available() {
return;
}
let mut checked = 0usize;
for (name, src, _, _) in dotted_aside_cases() {
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for e in &d.edges {
if e.stroke != Stroke::Dotted || e.from == e.to {
continue;
}
// Every crossing this aside actually makes against another edge, counted from the
// finished geometry — the aside must carry at least that many gaps of its own.
let crossings = d
.edges
.iter()
.filter(|o| !std::ptr::eq(*o, e))
.flat_map(|o| {
e.points.windows(2).flat_map(move |a| {
o.points
.windows(2)
.filter_map(move |b| orthogonal::segment_crossing(a, b))
})
})
.count();
assert_eq!(
e.gaps.len(),
crossings,
"{name}: the aside {}->{} crosses {crossings} other edge segments but carries \
{} gaps — the perimeter side is the one that has to be cut: {:?}",
e.from,
e.to,
e.gaps.len(),
e.points
);
for (g0, g1) in &e.gaps {
let arc = edges::arc_length_between(&e.points, g0, g1).unwrap_or_else(|| {
panic!(
"{name}: the aside {}->{}'s gap {g0:?}-{g1:?} is not on its own \
segments {:?}",
e.from, e.to, e.points
)
});
assert!(
(arc - orthogonal::CROSSING_GAP).abs() < 1e-6,
"{name}: the aside {}->{}'s gap removes {arc:.3}px of arc length, not \
{}px",
e.from,
e.to,
orthogonal::CROSSING_GAP
);
checked += 1;
}
}
}
assert!(
checked > 0,
"no forward aside crossed anything — the check is vacuous"
);
}
/// §10-0 ("線が複雑にならないこと — 交差は遠回りより悪い"), stated over the whole orthogonal corpus
/// for the lines [`orthogonal::perimeter_faces`] decides: **an aside on the perimeter ring never
/// crosses more main-flow lines than the best of its sixteen candidate face pairs would have.**
///
/// The two halves are measured differently on purpose. The left-hand side is the *drawn* line — the
/// polyline in the finished diagram, crossings counted against every line that is not itself on the
/// ring — so a route that picked the right faces and then lost them to eviction, a local detour or a
/// label plate is still caught. The right-hand side is `orthogonal::fewest_perimeter_crossings`, the
/// router's own candidate table, so "could it have done better" is answered by scoring the fifteen
/// pairs it did not take rather than by a second, hand-rolled idea of what the alternatives were.
///
/// Scoped to asides, which is exactly the set of riders `perimeter_faces` chooses faces for: a
/// genuine **back edge** on the same ring takes its two faces from dagre's own waypoint chain
/// (`classify`'s `is_reverse` branch calls `dominant_face`, never `perimeter_faces`), so there is no
/// candidate table to hold it to and this says nothing about it.
#[test]
fn invariant_orthogonal_aside_crosses_no_more_than_the_best_face_pair_could() {
if !text_metrics::fonts_available() {
return;
}
let mut checked = 0usize;
let mut with_a_crossing = 0usize;
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let content = diagram_content_box(&d);
let main_flow: Vec<Vec<Point>> = d
.edges
.iter()
.filter(|e| !rides_the_ring(e, content))
.map(|e| e.points.clone())
.collect();
for e in &d.edges {
if e.stroke != Stroke::Dotted || !rides_the_ring(e, content) {
continue;
}
let node_of = |id: &str| {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{name}: {id} is a node"))
};
let drawn = crossings_against(&e.points, &main_flow);
let best = orthogonal::fewest_perimeter_crossings(
node_of(&e.from),
node_of(&e.to),
&d.nodes,
&d.clusters,
&main_flow,
);
assert!(
drawn <= best,
"{name}: the aside {}->{} crosses {drawn} main-flow segments, but a face pair \
crossing only {best} was available — §10-0 makes a crossing worse than any \
detour: {:?}",
e.from,
e.to,
e.points
);
checked += 1;
with_a_crossing += usize::from(drawn > 0);
}
}
assert!(
checked >= 6,
"only {checked} perimeter-riding asides were checked — the corpus lost its dotted edges \
and the check is vacuous"
);
// Without a fixture whose every face pair crosses something, `drawn <= best` would hold for the
// trivial reason that both sides are always 0, and the ranking could be deleted without this
// test noticing (`orthogonal-aside-must-cross-a-leg-lr` is that fixture, and its own comment
// says why it exists).
assert!(
with_a_crossing > 0,
"no corpus aside crosses anything at all — `drawn <= best` is then vacuously true whatever \
`perimeter_faces` ranks by"
);
}
/// The defect the crossing term was added for (2026-09-05), pinned on the two design references
/// that showed it: `zz-design-2b`/`2c`'s own `UI -.->|リンク| PAY` leaves ブラウザ UI, goes round,
/// and **crosses nothing at all**.
///
/// Before the term, `2b`'s aside left ブラウザ UI's Right face — the short way, two corners — and
/// cut straight through `エディタ拡張 --> API` (one gapped crossing); `2c`'s cut a sibling's leg the
/// same way. The design draws neither: it takes the aside out of the picture's own body, which is
/// §10-1 item 4's whole reason for the perimeter lane.
///
/// Stated as "zero crossings against the whole rest of the diagram", not as a face name or a
/// coordinate: which face is free depends on where dagre puts the row, and pinning `Left` here
/// would fail for a layout that is just as correct. The corpus-wide sibling of this test
/// (`invariant_orthogonal_aside_crosses_no_more_than_the_best_face_pair_could`) is what states the
/// general rule; this one states that these two particular pictures actually reach zero.
#[test]
fn orthogonal_the_design_reference_asides_cross_nothing() {
if !text_metrics::fonts_available() {
return;
}
for name in ["zz-design-2a", "zz-design-2b", "zz-design-2c"] {
let src = orthogonal_design_reference_corpus()
.into_iter()
.find(|(n, _)| *n == name)
.unwrap_or_else(|| panic!("{name} is in the design-reference corpus"))
.1;
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let others: Vec<Vec<Point>> = d
.edges
.iter()
.filter(|e| e.stroke != Stroke::Dotted)
.map(|e| e.points.clone())
.collect();
let mut asides = 0usize;
for e in &d.edges {
if e.stroke != Stroke::Dotted || e.from == e.to {
continue;
}
asides += 1;
assert_eq!(
crossings_against(&e.points, &others),
0,
"{name}: the aside {}->{} must reach {} without crossing a single main-flow \
line — §10-0's own 交差は遠回りより悪い: {:?}",
e.from,
e.to,
e.to,
e.points
);
}
assert_eq!(asides, 1, "{name} carries exactly one author-dotted aside");
}
}
/// §10-3's own 8px nested-lane pitch, stated over the whole corpus for the shape
/// [`orthogonal::nest_merge_target_hops`] owns: two merge siblings' own hop legs never run
/// alongside each other closer than [`orthogonal::PORT_CLEARANCE`] px.
///
/// The sibling invariant next to this one
/// (`orthogonal_merge_sibling_hops_never_cross_or_coincide_across_corpus`) asks whether two routes
/// ever *meet*; this asks whether they ever fail to separate, which is a different question and
/// the one `zz-design-2b` failed: `ブラウザ UI`'s and `エディタ拡張`'s hops into `API ゲート` came
/// out **2.53px** apart and ran alongside each other for 37.4px, reading as one thick line. They
/// never touch, so nothing that asks about meeting could see it.
///
/// Scoped to the four-point "out, across, in" hop — `points.len() == 4` — which is exactly the
/// shape whose middle segment `nest_merge_target_hops` is free to move, and therefore exactly the
/// crowding it can be asked to fix. Two legs that do not overlap along the cross axis are not
/// running alongside each other at all and are out of scope by construction.
#[test]
fn orthogonal_merge_hop_legs_stay_eight_px_apart_across_the_corpus() {
use crate::preview::mermaid::flowchart::Direction;
if !text_metrics::fonts_available() {
return;
}
let mut checked = 0usize;
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
.chain([("settings-rules-sample", SETTINGS_RULES_SAMPLE)])
{
let direction = if src.contains("LR") || src.contains("RL") {
Direction::LeftToRight
} else {
Direction::TopToBottom
};
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
let mut by_target: HashMap<&str, Vec<&PlacedEdge>> = HashMap::new();
for e in &d.edges {
if e.stroke == Stroke::Invisible || e.points.len() != 4 {
continue;
}
by_target.entry(e.to.as_str()).or_default().push(e);
}
// The hop leg is the middle segment: its flow coordinate is the lane, its cross span is
// how much of the corridor it occupies.
let leg = |e: &PlacedEdge| -> (f64, f64, f64) {
let (a, b) = (&e.points[1], &e.points[2]);
let (lo, hi) = match direction {
Direction::TopToBottom | Direction::BottomToTop => (a.x.min(b.x), a.x.max(b.x)),
Direction::LeftToRight | Direction::RightToLeft => (a.y.min(b.y), a.y.max(b.y)),
};
let lane = match direction {
Direction::TopToBottom | Direction::BottomToTop => a.y,
Direction::LeftToRight | Direction::RightToLeft => a.x,
};
(lane, lo, hi)
};
for (target, merge) in by_target {
for i in 0..merge.len() {
for j in (i + 1)..merge.len() {
let (a, b) = (leg(merge[i]), leg(merge[j]));
// Only legs that genuinely run alongside each other.
if a.1.max(b.1) >= a.2.min(b.2) - 1e-6 {
continue;
}
checked += 1;
assert!(
(a.0 - b.0).abs() >= orthogonal::PORT_CLEARANCE - 1e-6,
"{name}: {}->{target} and {}->{target} run their hop legs {:.2}px apart \
over an overlapping stretch — §10-3's nested lanes are {}px: {:?} / {:?}",
merge[i].from,
merge[j].from,
(a.0 - b.0).abs(),
orthogonal::PORT_CLEARANCE,
merge[i].points,
merge[j].points
);
}
}
}
}
assert!(
checked > 0,
"no two merge hop legs overlapped anywhere in the corpus — the check is vacuous"
);
}
/// The vendored engine's own half of §10-1 item 4, tested against `layout()` directly rather than
/// through a diagram: an [`crate::preview::mermaid::layout::EdgeLabel::rank_only`] edge holds its
/// `minlen` through the rank phase and then leaves the graph before `normalize`, so it builds no
/// dummy chain, occupies no lane in the ranks it spans, and comes back as the plain two-point
/// border-to-border line an edge with no waypoints always gets.
///
/// `dummy_chains` is the graph label field `normalize::run` writes and `normalize::undo` reads —
/// one entry per long edge it split — so "did this edge become a chain" is answerable directly
/// rather than inferred from geometry. `A -> D` spans three ranks, which is exactly the shape that
/// produces one.
///
/// The second half is why the lift happens *after* ranking rather than instead of it: `Z` has no
/// in-edge but the rank-only one, and still ranks below `A`. Drop the edge before `rank::rank` and
/// `Z` falls to rank 0, above the node that links to it.
#[test]
fn rank_only_edges_hold_their_ranks_and_build_no_dummy_chain() {
use crate::preview::mermaid::layout::graph::{Graph, GraphOptions};
use crate::preview::mermaid::layout::{
layout, EdgeLabel, GraphLabel, LayoutOptions, NodeLabel,
};
let build = |rank_only: bool| -> Graph<NodeLabel, EdgeLabel> {
let mut g: Graph<NodeLabel, EdgeLabel> = Graph::with_options(GraphOptions {
directed: true,
multigraph: true,
compound: false,
});
for id in ["A", "B", "C", "D", "Z"] {
g.set_node(
id.to_string(),
Some(NodeLabel {
width: 40.0,
height: 20.0,
..NodeLabel::default()
}),
);
}
for (v, w) in [("A", "B"), ("B", "C"), ("C", "D")] {
g.set_edge(v, w, Some(EdgeLabel::default()), None);
}
// The long edge, and the one whose target nothing else reaches.
for (v, w, minlen) in [("A", "D", 3), ("A", "Z", 2)] {
g.set_edge(
v,
w,
Some(EdgeLabel {
minlen,
rank_only,
..EdgeLabel::default()
}),
None,
);
}
layout(&mut g, Some(LayoutOptions::default()));
g
};
let plain = build(false);
let lifted = build(true);
let chains = |g: &Graph<NodeLabel, EdgeLabel>| {
g.graph_label::<GraphLabel>()
.map(|gl| gl.dummy_chains.len())
.unwrap_or(0)
};
// Every edge here spans more than one rank once `make_space_for_edge_labels` has doubled every
// `minlen`, so the three `A-B-C-D` chain edges each produce a chain of their own either way;
// what the flag has to remove is exactly the two long edges' chains, no more and no fewer.
assert_eq!(
chains(&plain),
5,
"the fixture must produce one chain per edge without the flag, or it proves nothing"
);
assert_eq!(
chains(&lifted),
3,
"a rank-only edge must never be normalised into a dummy chain, and must not stop any other edge from being"
);
// Every edge handed in comes back, and the lifted ones carry exactly the two border points
// `assign_node_intersects` gives an edge with no waypoints of its own.
// `Graph::edges()`, not `edge_count()`: the cached counter drifts through `normalize`'s own
// add/remove churn in the vendored engine (measured: 3 for the unflagged graph, 6 for the
// flagged one, both of which really hold the same five edges), and nothing in the pipeline
// reads it — the descriptor list is the honest answer.
assert_eq!(
lifted.edges(),
plain.edges(),
"a rank-only edge must come back under the exact key it was handed in under"
);
for (v, w) in [("A", "D"), ("A", "Z")] {
let points = &lifted.edge(v, w, None).expect("the edge comes back").points;
assert_eq!(
points.len(),
2,
"{v}->{w} must be a plain two-point line for konoma to route itself: {points:?}"
);
}
// The ranking constraint is still in force, both for a node the flow also reaches (`D`, held
// three ranks below `A` by the long edge alongside the `A-B-C-D` chain) and for one only the
// rank-only edge reaches at all (`Z`).
let rank = |g: &Graph<NodeLabel, EdgeLabel>, id: &str| {
g.node(id)
.and_then(|n| n.rank)
.expect("every node is ranked")
};
// Ranks are counted in dagre's own doubled units — `make_space_for_edge_labels` doubles every
// `minlen` so a labelled edge has a rank of its own to put its label in — so `minlen: 3` holds
// `D` six ranks below `A`, and `minlen: 2` holds `Z` four.
assert_eq!(rank(&lifted, "D"), rank(&lifted, "A") + 6);
assert_eq!(
rank(&lifted, "Z"),
rank(&lifted, "A") + 4,
"Z ranks at {} against A's {} — a rank-only edge must still hold its own minlen, and it is the only thing ranking Z at all",
rank(&lifted, "Z"),
rank(&lifted, "A")
);
}
// =============================================================================================
// §10-8: node sizing under `konoma-orthogonal`
// =============================================================================================
//
// `docs/FEATURE-MERMAID-RENDERER.md` §10-8 (original: `docs/mermaid-theme/handoff/round5-Konoma-
// Flowchart-Routing.dc.html`, sections 5a and 5b). The 5b artboard is a set of worked examples
// drawn at 100%, which is exactly a set of assertions, so it is transcribed as one below and the
// rules it is drawn from are stated separately over the corpus.
/// The four worked examples 5b draws at 100%, each to the exact pixel.
///
/// These are the acceptance test for N1 and N2 and are written from the artboard's own numbers,
/// not from what the implementation produces: 「表」's box is `<rect width="96" height="36">`,
/// 「ブロックモデル」's is `144x36` (annotated "7 字 = 98px＋40px = 138px → 144"), and the decision
/// node's polygon spans `x=24..168` by `y=330..366` — 144x36 again, chamfer included.
///
/// The fourth (a left face with four ports, `max(36, 3x16+16) = 64`) is N4 rather than N1/N2, so
/// it is asserted through a real routed diagram in
/// [`orthogonal_five_b_merge_target_grows_to_its_four_ports`] instead of through `orthogonal_node`,
/// which only ever answers the label-derived half.
#[test]
fn orthogonal_node_reproduces_the_five_b_worked_examples() {
if !text_metrics::fonts_available() {
return;
}
let box_of = |glyph, text: &str| {
shapes::orthogonal_node(glyph, text)
.unwrap_or_else(|| panic!("{text}: {glyph:?} is in §10-8 N3's scope"))
.1
};
// 「表」: one CJK character, 14px of text. 14 + 40 = 54, floored at the 96px minimum.
assert_eq!(
box_of(Glyph::Flow(Shape::Rect), "表"),
Size::new(96.0, 36.0)
);
// 「ブロックモデル」: seven CJK characters, 98px of text. 98 + 40 = 138, rounded up to 144.
assert_eq!(
text_metrics::measure("ブロックモデル", 14.0) as f64,
98.0,
"5b's own annotation — the artboard's arithmetic starts from this measurement"
);
assert_eq!(
box_of(Glyph::Flow(Shape::Rect), "ブロックモデル"),
Size::new(144.0, 36.0)
);
// 「ルールに一致?」 as a decision node: 91.79px of text, +40 padding, +12 for the two 6px
// chamfers = 143.79, rounded up to 144 — the polygon 5b draws spans exactly that.
assert_eq!(
box_of(Glyph::ChamferedRect, "ルールに一致?"),
Size::new(144.0, 36.0)
);
}
/// 5b's third example, which is N4 rather than N1/N2 and therefore only observable on a routed
/// diagram: a merge target whose face carries four ports grows along **that face's axis only**,
/// by `(n-1) * PORT_SPACING + 2 * PORT_CLEARANCE`, and stays centred on its own middle.
///
/// **Where konoma and 5b's drawing differ, and why the difference is not this rule breaking.** 5b
/// draws the four ports centred on the face — `±8`, `±24` — which makes the box `3*16 + 16 = 64`
/// tall. konoma puts one of the four *on* the centre line, because §10-3 item 12 anchors a merge's
/// own trunk claim at its natural sort position and §10-3 item 10 promotes a median source to be
/// that trunk: `合流先` is reached by a straight, zero-bend edge, which is only possible if that
/// edge's port is the face's own centre. The remaining three then sit at `-16`, `+16`, `+32`, and
/// N4's own arithmetic — the outermost port plus its 8px corner clearance, doubled for symmetry —
/// gives 80 rather than 64. The formula is the same formula; 5b's *64* is the value it takes on a
/// face with no trunk on it, which this test pins separately just below. Straightening the spine
/// is what §10-0 ranks first, so the centred trunk port stays and 5b's centred four is recorded
/// here as the arithmetic it is rather than forced onto a diagram that would then bend.
///
/// `LR` so the four merges land on the target's **left** face, which is the face 5b draws them on
/// — under §10-3 item 3 a merge always rides the flow-axis face, so the direction is what puts
/// them there rather than a special case.
#[test]
fn orthogonal_five_b_merge_target_grows_to_its_four_ports() {
if !text_metrics::fonts_available() {
return;
}
// 5b's own arithmetic, on the centred four-port face it draws: "16px×3＋両端 8px = 64px".
assert_eq!(
3.0 * orthogonal::PORT_SPACING + 2.0 * orthogonal::PORT_CLEARANCE,
64.0
);
let d = laid_out_flow(
"flowchart LR\n A[あ] --> Z[合流先]\n B[い] --> Z\n C[う] --> Z\n D[え] --> Z",
"basis",
"konoma-orthogonal",
);
let z = d.node("Z").expect("Z must exist");
let (left, top, _, bottom) = z.bounds();
let mut ys: Vec<f64> = d
.edges
.iter()
.filter(|e| e.to == "Z")
.map(|e| {
let p = e.points.last().expect("routed");
assert!(
(p.x - (left - orthogonal::PORT_INSET)).abs() < 1e-6,
"5b puts all four ports on Z's own left face: {p:?} vs left {left}"
);
p.y
})
.collect();
assert_eq!(ys.len(), 4, "all four sources must reach Z");
ys.sort_by(|a, b| a.partial_cmp(b).expect("finite"));
// 16px pitch, and 8px of corner clearance at each end — N4's two terms, read off the picture.
for w in ys.windows(2) {
assert_eq!(
w[1] - w[0],
orthogonal::PORT_SPACING,
"the four ports sit on the 16px grid: {ys:?}"
);
}
let reach = (ys[3] - z.center.y).abs().max((ys[0] - z.center.y).abs());
assert_eq!(
z.size.h,
2.0 * (reach + orthogonal::PORT_CLEARANCE),
"N4: the face is the outermost port plus its 8px clearance, doubled — {ys:?}"
);
assert!(
ys[0] - top >= orthogonal::PORT_CLEARANCE - 1e-6
&& bottom - ys[3] >= orthogonal::PORT_CLEARANCE - 1e-6,
"no port may sit closer than 8px to its face's own corner: {ys:?} in {top}..{bottom}"
);
let (_, label_box) =
shapes::orthogonal_node(z.shape, "合流先").expect("a plain rectangle is in scope");
assert!(
z.size.h > label_box.h,
"the ports are what grew it: {:?} vs {label_box:?}",
z.size
);
assert_eq!(
z.size.w, label_box.w,
"N4: growth is along the ports' own axis only — the width stays label-derived"
);
assert!(
((top + bottom) / 2.0 - z.center.y).abs() < 1e-6,
"N4: the grown box stays symmetric about its own centre line"
);
}
/// N2's 96px floor, and the exact width the floor gives way at.
///
/// Both sides of the boundary, so neither "always 96" nor "never 96" can pass: 56px of text pads
/// to exactly 96 and is the widest label the minimum still covers, and a hair more rounds up to
/// the next 8px step.
#[test]
fn orthogonal_width_floors_at_ninety_six_then_follows_the_text() {
let w = |t: f64| shapes::ortho_width(Glyph::Flow(Shape::Rect), t);
assert_eq!(w(0.0), 96.0, "an empty label still gets N2's minimum");
assert_eq!(w(20.0), 96.0);
assert_eq!(w(56.0), 96.0, "56 + 40 = 96 exactly — still the minimum");
assert_eq!(w(56.5), 104.0, "past the minimum, the 8px grid takes over");
assert_eq!(w(58.0), 104.0, "58 + 40 = 98 -> 104");
}
/// N2's "8px 単位に切り上げ", at every residue class — a rounding that only worked for multiples of
/// 8 would pass a single-value check.
#[test]
fn orthogonal_width_rounds_up_onto_the_eight_pixel_grid() {
for text in [
58.0, 60.0, 63.9, 64.0, 64.1, 71.9, 72.0, 100.0, 137.5, 160.0,
] {
let w = shapes::ortho_width(Glyph::Flow(Shape::Rect), text);
assert_eq!(
w % shapes::ORTHO_WIDTH_STEP,
0.0,
"text {text} -> {w} must land on the 8px grid"
);
assert!(
w >= text + 2.0 * shapes::ORTHO_PAD_X,
"text {text} -> {w} must still hold the words plus 20px a side"
);
assert!(
w < text + 2.0 * shapes::ORTHO_PAD_X + shapes::ORTHO_WIDTH_STEP
|| w == shapes::ORTHO_MIN_WIDTH,
"text {text} -> {w} must round UP, not up-and-then-some"
);
}
// Exactly on the grid already: rounding up must be the identity, not one more step.
assert_eq!(
shapes::ortho_width(Glyph::Flow(Shape::Rect), 104.0 - 40.0),
104.0
);
}
/// N3's chamfer allowance: the same words in a decision node get 6px more padding a side than in
/// a plain rectangle — 12px in all, before the 8px rounding.
#[test]
fn orthogonal_decision_node_pays_six_more_pixels_a_side_for_its_chamfer() {
// Chosen so neither value is on the 96px floor and the 12px difference cannot be swallowed by
// the 8px rounding (both land on their own step).
let text = 108.0;
let rect = shapes::ortho_width(Glyph::Flow(Shape::Rect), text);
let decision = shapes::ortho_width(Glyph::ChamferedRect, text);
assert_eq!(rect, 152.0, "108 + 40 = 148 -> 152");
assert_eq!(
decision, 160.0,
"108 + 40 + 12 = 160, already on the grid — 8px more box for the two 6px chamfers"
);
assert_eq!(
decision - rect,
8.0,
"the chamfer allowance survives the rounding rather than being rounded away"
);
}
/// N1's height for k lines, `14k + 6(k-1) + 22`, and the identity the drawing path depends on: the
/// box is exactly the label block [`super::svg::emit_text`] centres inside it plus 2 x
/// [`shapes::ORTHO_PAD_Y`]. The doc on [`shapes::ortho_height`] names this test for that reason —
/// if the two spellings ever disagree, the words drift off centre in every multi-line node.
#[test]
fn orthogonal_box_height_is_the_label_block_plus_padding() {
for (k, expected) in [(1, 36.0), (2, 56.0), (3, 76.0), (4, 96.0)] {
assert_eq!(shapes::ortho_height(k), expected, "{k} lines");
let block = k as f64 * super::labels::ortho_line_pitch();
assert_eq!(
shapes::ortho_height(k),
block + 2.0 * shapes::ORTHO_PAD_Y - super::labels::ORTHO_LINE_GAP,
"{k} lines: the box must be the drawn block plus N1's own padding"
);
}
assert_eq!(
super::labels::ortho_line_pitch(),
20.0,
"N1: 14px of text and a 6px gap"
);
}
/// N2's cap: a label too wide for 240px wraps at a word boundary and the box grows *down* instead
/// of out — two lines, `14*2 + 6 + 22 = 56` tall.
#[test]
fn orthogonal_label_wider_than_the_cap_wraps_instead_of_widening() {
if !text_metrics::fonts_available() {
return;
}
let text = "resolve the preview kind and hand it to the right renderer";
let one_line = text_metrics::measure(text, 14.0) as f64;
assert!(
one_line + 2.0 * shapes::ORTHO_PAD_X > shapes::ORTHO_MAX_WIDTH,
"the fixture must actually be over the cap: {one_line}px of text"
);
let (label, size) =
shapes::orthogonal_node(Glyph::Flow(Shape::Rect), text).expect("a rectangle is in scope");
assert!(
label.lines.len() >= 2,
"it must wrap, not overflow: {:?}",
label.lines
);
assert_eq!(
size.h,
shapes::ortho_height(label.lines.len()),
"N1's height for however many lines it took"
);
assert!(
size.w <= shapes::ORTHO_MAX_WIDTH,
"wrapping must bring it back under the cap: {size:?}"
);
// Nothing is thrown away and nothing is invented — the words come back in order, whole.
assert_eq!(
label.lines.join(" "),
text,
"N2 forbids truncation and an ellipsis alike"
);
for line in &label.lines {
assert!(
!line.contains('…') && !line.ends_with("..."),
"no ellipsis: {line:?}"
);
}
}
/// N2's exact wrap: a label that is *just* over the cap comes back as two lines and 56px tall,
/// pinning the height formula for `k = 2` on a real label rather than on `ortho_height` alone.
#[test]
fn orthogonal_two_line_wrap_is_fifty_six_pixels_tall() {
if !text_metrics::fonts_available() {
return;
}
// 16 CJK characters = 224px of text; 224 + 40 = 264 > 240, and any 15 of them (210 + 40 = 250)
// would still be over, so this genuinely exercises the per-character CJK rule.
let text = "設定のルールに従って描画方法を決める";
let (label, size) =
shapes::orthogonal_node(Glyph::Flow(Shape::Rect), text).expect("a rectangle is in scope");
assert_eq!(label.lines.len(), 2, "two lines: {:?}", label.lines);
assert_eq!(size.h, 56.0, "14*2 + 6 + 22 = 56");
assert_eq!(
label.lines.concat(),
text,
"CJK wraps between characters, and no character is lost or added"
);
assert!(
label.lines.iter().all(|l| l.chars().count() > 1),
"per character does not mean one character per line: {:?}",
label.lines
);
}
/// N2's own escape hatch: a single unbreakable run wider than the cap keeps its box rather than
/// being cut. "折り返し後も超える場合のみ上限を撤廃（切らない・省略記号なし）".
#[test]
fn orthogonal_unbreakable_run_widens_past_the_cap_rather_than_being_truncated() {
if !text_metrics::fonts_available() {
return;
}
let text = "A".repeat(30);
let (label, size) =
shapes::orthogonal_node(Glyph::Flow(Shape::Rect), &text).expect("a rectangle is in scope");
assert_eq!(
label.lines,
vec![text.clone()],
"there is nowhere to break, so it stays one line"
);
assert!(
size.w > shapes::ORTHO_MAX_WIDTH,
"the cap gives way, the text does not: {size:?}"
);
assert_eq!(
size.w,
shapes::ortho_width(Glyph::Flow(Shape::Rect), label.width),
"still padded and still on the 8px grid — only the cap is lifted"
);
assert_eq!(size.h, 36.0, "one line is still one line");
}
/// The mixed case the two rules above meet in: a long unbreakable token *and* ordinary words. The
/// words wrap around the token, the token keeps its own line whole, and the box is as wide as the
/// token needs.
#[test]
fn orthogonal_wrapping_keeps_a_long_token_whole_and_wraps_the_words_around_it() {
if !text_metrics::fonts_available() {
return;
}
let token = "A".repeat(30);
let text = format!("open {token} now please and then some more words");
let (label, _) =
shapes::orthogonal_node(Glyph::Flow(Shape::Rect), &text).expect("a rectangle is in scope");
assert!(
label.lines.iter().any(|l| l.contains(&token)),
"the token is never split: {:?}",
label.lines
);
assert_eq!(label.lines.join(" "), text, "every word survives, in order");
assert!(
label.lines.len() >= 3,
"the words either side of it wrap: {:?}",
label.lines
);
}
/// N3's exclusions, stated where they are decided. A glyph out of scope must come back `None` so
/// that `spec_of` falls through to mermaid's own [`shapes::size`] — the state markers, a choice, a
/// fork/join bar (all of which §10-5 S1/S4 size), and every shape with geometry of its own.
#[test]
fn orthogonal_node_sizing_leaves_n3s_exclusions_to_mermaids_own_sizes() {
for glyph in [
Glyph::StateStart,
Glyph::StateEnd,
Glyph::Choice,
Glyph::Bar { horizontal: true },
Glyph::Bar { horizontal: false },
Glyph::Note,
Glyph::Flow(Shape::Circle),
Glyph::Flow(Shape::DoubleCircle),
Glyph::Flow(Shape::Stadium),
Glyph::Flow(Shape::Hexagon),
Glyph::Flow(Shape::Cylinder),
Glyph::Flow(Shape::Subroutine),
Glyph::Flow(Shape::Diamond),
Glyph::Flow(Shape::Trapezoid),
] {
assert!(
shapes::orthogonal_node(glyph, "text").is_none(),
"{glyph:?} is outside §10-8 N3 and must keep mermaid's own size"
);
assert!(!shapes::orthogonal_covers(glyph), "{glyph:?}");
}
for glyph in [
Glyph::Flow(Shape::Rect),
Glyph::Flow(Shape::RoundedRect),
Glyph::ChamferedRect,
Glyph::TitledBox,
] {
assert!(
shapes::orthogonal_covers(glyph),
"{glyph:?} is a box §10-8 sizes"
);
}
}
/// §10-8 applies **only** to `konoma-orthogonal`. Every splines box comes back exactly as
/// [`shapes::size`] alone would have made it — the same claim `splines_routing_signature_is_pinned`
/// and the goldens make about the whole byte stream, stated here on the one thing this change
/// touched, in a form that fails loudly rather than through a snapshot diff.
#[test]
fn splines_node_sizes_are_untouched_by_the_orthogonal_rules() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_full_corpus() {
let d = laid_out_curve(src, "basis");
for n in &d.nodes {
let expected = shapes::size(n.shape, Size::new(n.label.width, n.label.height));
assert_eq!(
(n.size.w, n.size.h),
(expected.w, expected.h),
"{name}: {} must keep mermaid's own size under splines",
n.id
);
assert_eq!(
n.label.line_pitch,
super::labels::line_height(),
"{name}: {} must keep mermaid's own 1.1em line pitch under splines",
n.id
);
}
}
}
/// N1-N4 as a corpus-wide invariant, over every source the orthogonal mode is checked against.
///
/// Four separate claims, because each can fail on its own:
///
/// 1. no box is ever **smaller** than its own label asks for (N4's `max`, from the label side);
/// 2. a width is either exactly the label-derived one — on the 8px grid, at least 96 — or a
/// port-derived one, which is `2*(k*8 + PORT_CLEARANCE)` plus a chamfered node's own allowance;
/// 3. a height is either N1's `14k + 6(k-1) + 22` or, again, a port-derived value on that grid;
/// 4. the box is symmetric about its own centre, so growth never slid a node sideways.
///
/// "Or port-derived" is not a loophole: `apply_growth` never shrinks (`mod.rs`'s own doc on why
/// that is what makes the retry loop converge), so a face that needed room in an early pass keeps
/// it even if a later pass reroutes the edge that asked. What must stay true is that any box
/// bigger than its label is bigger by exactly what some face's port grid asks for — never by an
/// arbitrary amount.
#[test]
fn orthogonal_every_box_is_label_derived_or_on_the_port_grid() {
if !text_metrics::fonts_available() {
return;
}
let on_port_grid = |v: f64, glyph: Glyph| {
let chamfer = if glyph == Glyph::ChamferedRect {
2.0 * shapes::CHAMFER
} else {
0.0
};
let reach = (v - chamfer) / 2.0 - orthogonal::PORT_CLEARANCE;
reach >= -1e-6 && (reach / (orthogonal::PORT_SPACING / 2.0)).fract().abs() < 1e-6
};
let mut checked = 0usize;
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for n in &d.nodes {
if !shapes::orthogonal_covers(n.shape) {
continue;
}
checked += 1;
let label_box = shapes::orthogonal_label_box(n.shape, &n.label);
assert!(
n.size.w >= label_box.w - 1e-6 && n.size.h >= label_box.h - 1e-6,
"{name}: {} is smaller than its own label needs: {:?} vs {label_box:?}",
n.id,
n.size
);
assert_eq!(
label_box.w % shapes::ORTHO_WIDTH_STEP,
0.0,
"{name}: {}'s label-derived width must be on the 8px grid",
n.id
);
assert!(
label_box.w >= shapes::ORTHO_MIN_WIDTH,
"{name}: {}'s label-derived width must be at least 96",
n.id
);
assert_eq!(
label_box.h,
shapes::ortho_height(n.label.lines.len()),
"{name}: {}'s label-derived height must be N1's own",
n.id
);
if (n.size.w - label_box.w).abs() > 1e-6 {
assert!(
on_port_grid(n.size.w, n.shape),
"{name}: {} is wider than its label by something that is not a port grid: \
{:?} vs {label_box:?}",
n.id,
n.size
);
}
if (n.size.h - label_box.h).abs() > 1e-6 {
assert!(
on_port_grid(n.size.h, n.shape),
"{name}: {} is taller than its label by something that is not a port grid: \
{:?} vs {label_box:?}",
n.id,
n.size
);
}
let (l, t, r, b) = n.bounds();
assert!(
((l + r) / 2.0 - n.center.x).abs() < 1e-6
&& ((t + b) / 2.0 - n.center.y).abs() < 1e-6,
"{name}: {}'s box must stay symmetric about its own centre",
n.id
);
}
}
assert!(
checked > 100,
"the corpus must actually reach the boxes §10-8 sizes: only {checked} seen"
);
}
/// N1/N2's padding, checked as the thing padding is *for*: no node's words touch its box.
///
/// Measured against the drawn label block ([`super::labels::Label`]'s own width and the pitch
/// [`super::svg::emit_text`] steps by), not against a second guess at the text extent, and stated
/// with a 1px slack because a rounded-up width can leave a hair more room than the padding alone.
#[test]
fn orthogonal_no_node_text_overflows_its_own_box() {
if !text_metrics::fonts_available() {
return;
}
for (name, src) in orthogonal_full_corpus()
.into_iter()
.chain(orthogonal_only_corpus())
{
let d = laid_out_flow(src, "basis", "konoma-orthogonal");
for n in &d.nodes {
if !shapes::orthogonal_covers(n.shape) || n.label.is_blank() {
continue;
}
let pad_x = shapes::ORTHO_PAD_X
+ if n.shape == Glyph::ChamferedRect {
shapes::CHAMFER
} else {
0.0
};
assert!(
n.label.width <= n.size.w - 2.0 * pad_x + 1.0,
"{name}: {}'s words ({:.2}px) run into its own {:.2}px box",
n.id,
n.label.width,
n.size.w
);
// The ink is `14k + 6(k-1)`; the label block carries half a line gap above the first
// line and below the last, which is what centres it — so the comparison subtracts one
// gap rather than pretending the block and the ink are the same number.
let ink = n.label.height - super::labels::ORTHO_LINE_GAP;
assert!(
ink <= n.size.h - 2.0 * shapes::ORTHO_PAD_Y + 1e-6,
"{name}: {}'s {} line(s) run past its own {:.2}px box",
n.id,
n.label.lines.len(),
n.size.h
);
}
}
}
// =============================================================================================
// `direction`'s **sign** — `RL` is `LR` mirrored, `BT` is `TB` mirrored
// (`docs/FEATURE-MERMAID-RENDERER.md` §10; `super::canonicalise_flow_axis`/`super::
// mirror_flow_axis`)
//
// Under `konoma-orthogonal` all four directions used to come out of the same two layouts: every
// post-dagre pass keys on the flow *axis* without its *sign*, and `pull_back_fan_ranks` rewrote
// every node's flow coordinate as "ascending with rank" for all four — so `RL` rendered
// byte-identical to `LR` and `BT` to `TB` (measured on the sample flowchart: `Key press` at x=50.4
// and `Redraw` at x=636.6 under both `LR` and `RL`, where splines puts them at 50.4/645.9 and
// 657.6/62.1 — a real mirror). dagre's own edge waypoints were *not* rewritten, so the eight corpus
// sources with a self-loop or a staircase fallback came out worse than identical: `self-loop`'s own
// `A --> A` under `BT` was drawn around `B`'s box (y 88-130) while `A` sat at y 26.
// =============================================================================================
/// `samples/mermaid.md`'s **first** flowchart, byte-for-byte — the diagram the direction bug was
/// found on, kept here as a source rather than read off disk for the same reason
/// [`SETTINGS_RULES_SAMPLE`] is: several tests below need this exact string, and a fixture nobody
/// can diff against the sample is worse than one copy of it.
const SAMPLE_FIRST_FLOWCHART: &str = "flowchart LR\n K([Key press]) --> S{Which surface?}\n \
S -->|Tree| M[Move or open]\n S -->|Preview| P[Scroll or search]\n M --> R[Redraw]\n \
P --> R";
/// One source carrying every shape whose §10 rule is stated **flow-relative** and therefore has to
/// mirror, so that a mirror test over it is not just a test of ordinary boxes and straight lines:
///
/// * a **fan** wide enough for §10-3 item 1's own multi-branch regime (five branches, past
/// `orthogonal::FAN_ELIGIBLE_MIN_BRANCHES`), whose ports go on the source's *flow-direction* face;
/// * the **merge** back onto one target, whose ports go on that target's own *upstream* flow face
/// (§10-3 item 10) — the face that is the left one under `LR` and the right one under `RL`;
/// * an **aside** (`-.->`, `render::is_aside`) that is also a **back edge**, so the outer perimeter
/// lane (§10-1 item 4) is in the picture;
/// * a **self-loop**, the one shape still drawn from dagre's own waypoints
/// (`orthogonal::route_staircase_with_ports`) and so the one that catches a waypoint set left
/// behind in the un-mirrored space;
/// * a **dead-end tier** — a block whose members are all dead ends fed from the trunk and which the
/// trunk does not itself run through (`orthogonal::place_dead_end_tiers`), whose side is chosen on
/// the *cross* axis and must therefore come out on the **same** side under both directions;
/// * **edge labels**, so the label plates and their §10-1 item 3 minimum segment lengths are in it.
const FAN_MERGE_ASIDE_TIER: &str = "flowchart LR\n A[入力] --> D{振り分け}\n \
D -->|1| B1[枝一]\n D -->|2| B2[枝二]\n D -->|3| B3[枝三]\n D -->|4| B4[枝四]\n \
D -->|5| B5[枝五]\n B1 --> M[合流]\n B2 --> M\n B3 --> M\n B4 --> M\n B5 --> M\n \
M --> Z[出力]\n subgraph T[控え]\n T1[記録]\n T2[計測]\n end\n M --> T1\n \
M --> T2\n Z -.->|再試行| A\n Z --> Z";
/// The sources [`orthogonal_rl_is_the_exact_mirror_of_lr`] and its `BT` sibling state the mirror
/// over — the two above plus [`SETTINGS_RULES_SAMPLE`], the twenty-node sample §10-3 was written
/// against, because a source this size is where a pass that silently drops the sign shows up.
fn direction_fixture_sources() -> Vec<(&'static str, &'static str)> {
vec![
("sample-first-flowchart", SAMPLE_FIRST_FLOWCHART),
("fan-merge-aside-tier", FAN_MERGE_ASIDE_TIER),
("settings-rules-sample", SETTINGS_RULES_SAMPLE),
]
}
/// [`direction_fixture_sources`], minus the ones whose **`TB` form** trips a corpus-wide invariant
/// for a reason that has nothing to do with `direction`.
///
/// [`SETTINGS_RULES_SAMPLE`] is the one: it is authored `LR` (and is drawn `LR` everywhere it is
/// used), and laying the same graph out `TB` puts `設定のルール`'s own `Markdown` label plate over
/// the neighbouring `画像` edge, and orders two of `ラスタライズ`'s merge hop legs widest-last.
/// Both reproduce with the flow-axis mirror disabled — they are pre-existing `TB` layout faults
/// this task did not introduce and is not scoped to fix (recorded rather than papered over; the
/// mirror tests above still run this source in all four directions, and it mirrors exactly).
fn direction_corpus_sources() -> Vec<(&'static str, &'static str)> {
direction_fixture_sources()
.into_iter()
.filter(|(name, _)| *name != "settings-rules-sample")
.collect()
}
/// The same source with its header's `direction` keyword replaced — `flowchart LR` into
/// `flowchart RL`, and so on. Panics rather than returning an `Option`: every caller is a test with
/// a source it wrote itself, so a header this cannot read is a mistake in the test, not a case to
/// skip silently.
pub(super) fn flowchart_with_direction(src: &str, direction: &str) -> String {
let (head, rest) = src.split_once('\n').unwrap_or((src, ""));
let mut words = head.split_whitespace();
let kind = words
.next()
.filter(|w| matches!(*w, "flowchart" | "graph"))
.unwrap_or_else(|| {
panic!("a flowchart fixture starts with `flowchart` or `graph`: {head}")
});
assert!(
words
.next()
.is_none_or(|w| matches!(w, "TB" | "TD" | "BT" | "LR" | "RL")),
"a flowchart fixture's header carries nothing but a direction: {head}"
);
format!("{kind} {direction}\n{rest}")
}
/// [`direction_corpus_sources`] in all four directions, plus every
/// [`orthogonal_design_reference_corpus`] source in the direction that reverses its own — chained
/// into [`orthogonal_full_corpus`], so every corpus-wide invariant (axis-parallel segments,
/// perpendicular entry, no puncture, no crossing, frames holding their members…) runs over the
/// reversed half of each axis too, which before the mirror existed nothing did.
///
/// **Derived, not copied.** Writing `flowchart RL` variants out by hand would be four more
/// near-duplicates of sources that already have one near-duplicate each (`2b`/`2c` are the same
/// graph in `LR` and `TB`), and a hand copy drifts from the source it mirrors the first time either
/// is edited. Built once into a [`OnceLock`] so the borrowed `&'static str`s outlive every caller.
///
/// [`OnceLock`]: std::sync::OnceLock
fn orthogonal_reversed_direction_corpus() -> &'static [(String, String)] {
static CACHE: std::sync::OnceLock<Vec<(String, String)>> = std::sync::OnceLock::new();
CACHE.get_or_init(|| {
let mut out: Vec<(String, String)> = Vec::new();
for (name, src) in direction_corpus_sources() {
for direction in ["LR", "RL", "TB", "BT"] {
out.push((
format!("{name}-{direction}"),
flowchart_with_direction(src, direction),
));
}
}
for (name, src) in orthogonal_design_reference_corpus() {
let reversed = match src
.lines()
.next()
.unwrap_or_default()
.split_whitespace()
.nth(1)
{
Some("LR") => "RL",
Some("RL") => "LR",
Some("BT") => "TB",
// `flowchart` with nothing after it is `TB`, the parser's own default.
Some("TB") | Some("TD") | None => "BT",
Some(other) => panic!("{name}: unknown direction {other}"),
};
out.push((
format!("{name}-{reversed}"),
flowchart_with_direction(src, reversed),
));
}
out
})
}
/// How far two coordinates may differ and still be the same point. The mirror is a reflection of
/// finished geometry — one negation and one translation, both exact in binary floating point for
/// the magnitudes a diagram uses — so this is a guard against a stray rounding, not a tolerance
/// the implementation is expected to need.
pub(super) const MIRROR_EPS: f64 = 1e-6;
/// Asserts `b` is `a` reflected along the flow axis: every coordinate on that axis at `span - v`
/// (`span` being the diagram's own extent along it), every coordinate across it unchanged, and
/// every size, id and ordering identical.
///
/// Shared with [`super::state_tests`], which states the same property over a state diagram's own
/// design references.
pub(super) fn assert_mirrored_diagrams(label: &str, a: &Diagram, b: &Diagram, vertical: bool) {
assert!(
(a.width - b.width).abs() < MIRROR_EPS && (a.height - b.height).abs() < MIRROR_EPS,
"{label}: a mirror keeps the diagram's own size — {}x{} became {}x{}",
a.width,
a.height,
b.width,
b.height
);
let span = if vertical { a.height } else { a.width };
// `(flow, cross)` of a point, with the flow coordinate already reflected on `b`'s side, so the
// two sides below are compared with one `assert` rather than two mirrored ones.
let split = |p: &Point, mirrored: bool| -> (f64, f64) {
let (flow, cross) = if vertical { (p.y, p.x) } else { (p.x, p.y) };
(if mirrored { span - flow } else { flow }, cross)
};
let same = |what: &str, id: &str, pa: &Point, pb: &Point| {
let ((fa, ca), (fb, cb)) = (split(pa, false), split(pb, true));
assert!(
(fa - fb).abs() < MIRROR_EPS && (ca - cb).abs() < MIRROR_EPS,
"{label}: {what} {id} sits at {pa:?}, whose mirror is flow {fa} cross {ca} — \
the reversed direction drew it at {pb:?} (flow {fb} cross {cb})"
);
};
assert_eq!(
a.nodes.iter().map(|n| &n.id).collect::<Vec<_>>(),
b.nodes.iter().map(|n| &n.id).collect::<Vec<_>>(),
"{label}: a mirror keeps every node, in order"
);
for (na, nb) in a.nodes.iter().zip(&b.nodes) {
assert_eq!(
(na.size.w, na.size.h),
(nb.size.w, nb.size.h),
"{label}: node {}'s own box is reflected, not resized",
na.id
);
assert_eq!(
na.shape, nb.shape,
"{label}: node {}'s own glyph is unchanged by the direction",
na.id
);
same("node", &na.id, &na.center, &nb.center);
}
assert_eq!(
a.clusters.iter().map(|c| &c.id).collect::<Vec<_>>(),
b.clusters.iter().map(|c| &c.id).collect::<Vec<_>>(),
"{label}: a mirror keeps every frame, in order"
);
for (ca, cb) in a.clusters.iter().zip(&b.clusters) {
assert_eq!(
(ca.size.w, ca.size.h),
(cb.size.w, cb.size.h),
"{label}: frame {}'s own rectangle is reflected, not resized",
ca.id
);
same("frame", &ca.id, &ca.center, &cb.center);
}
assert_eq!(
a.edges.iter().map(|e| (&e.from, &e.to)).collect::<Vec<_>>(),
b.edges.iter().map(|e| (&e.from, &e.to)).collect::<Vec<_>>(),
"{label}: a mirror keeps every edge, in order"
);
for (ea, eb) in a.edges.iter().zip(&b.edges) {
let id = format!("{}->{}", ea.from, ea.to);
assert_eq!(
ea.points.len(),
eb.points.len(),
"{label}: edge {id} is the same route reflected, so it has the same number of \
corners — {:?} against {:?}",
ea.points,
eb.points
);
for (pa, pb) in ea.points.iter().zip(&eb.points) {
same("edge", &id, pa, pb);
}
assert_eq!(
ea.gaps.len(),
eb.gaps.len(),
"{label}: edge {id} keeps its own §10-1 item 4 crossing gaps"
);
for ((a0, a1), (b0, b1)) in ea.gaps.iter().zip(&eb.gaps) {
same("gap start", &id, a0, b0);
same("gap end", &id, a1, b1);
}
for (what, la, lb) in [
("label", &ea.label, &eb.label),
("start label", &ea.start_label, &eb.start_label),
("end label", &ea.end_label, &eb.end_label),
("badge", &ea.badge, &eb.badge),
] {
match (la, lb) {
(Some(la), Some(lb)) => {
assert_eq!(
(la.size.w, la.size.h),
(lb.size.w, lb.size.h),
"{label}: edge {id}'s {what} is moved, not re-measured"
);
same(what, &id, &la.center, &lb.center);
}
(None, None) => {}
_ => panic!("{label}: edge {id} has a {what} in one direction and not the other"),
}
}
}
}
/// §10 under `RL`: the same drawing as `LR`, reflected along x.
///
/// The **whole** drawing, not a sample of it — node centres, frame rectangles, every polyline
/// vertex (which is where the ports are: a route's first and last point *is* its port, pulled
/// `PORT_INSET` outside the face), every crossing gap and every label plate. Stated as an exact
/// reflection rather than as "looks different from `LR`" because that is what the direction
/// actually means, and because a weaker statement passes on a drawing that is merely translated.
#[test]
fn orthogonal_rl_is_the_exact_mirror_of_lr() {
for (name, src) in direction_fixture_sources()
.into_iter()
.chain(orthogonal_design_reference_corpus())
{
let lr = laid_out_flow(
&flowchart_with_direction(src, "LR"),
"basis",
"konoma-orthogonal",
);
let rl = laid_out_flow(
&flowchart_with_direction(src, "RL"),
"basis",
"konoma-orthogonal",
);
assert_mirrored_diagrams(&format!("{name} LR/RL"), &lr, &rl, false);
}
}
/// §10 under `BT`: the same drawing as `TB`, reflected along y. [`orthogonal_rl_is_the_exact_
/// mirror_of_lr`]'s own doc has the reasoning; this is the other axis.
#[test]
fn orthogonal_bt_is_the_exact_mirror_of_tb() {
for (name, src) in direction_fixture_sources()
.into_iter()
.chain(orthogonal_design_reference_corpus())
{
let tb = laid_out_flow(
&flowchart_with_direction(src, "TB"),
"basis",
"konoma-orthogonal",
);
let bt = laid_out_flow(
&flowchart_with_direction(src, "BT"),
"basis",
"konoma-orthogonal",
);
assert_mirrored_diagrams(&format!("{name} TB/BT"), &tb, &bt, true);
}
}
/// The mirror is a **reflection**, not a relabelling: `RL` must not simply come out as `LR` again.
///
/// The bug this pins was exactly that — every one of the four directions produced one of two
/// layouts — so a mirror suite alone could be satisfied by a diagram whose flow axis happens to be
/// symmetric. This states the thing that cannot be true of one: the reversed direction moves the
/// **first** node past the middle of the diagram and the last one back before it.
#[test]
fn orthogonal_reversing_the_direction_actually_moves_the_flow() {
for (name, src) in direction_fixture_sources() {
for (forward, reverse, vertical) in [("LR", "RL", false), ("TB", "BT", true)] {
let a = laid_out_flow(
&flowchart_with_direction(src, forward),
"basis",
"konoma-orthogonal",
);
let b = laid_out_flow(
&flowchart_with_direction(src, reverse),
"basis",
"konoma-orthogonal",
);
let head = &a.nodes[0].id;
let flow = |d: &Diagram, id: &str| {
let n = d.nodes.iter().find(|n| n.id == id).expect("node exists");
if vertical {
n.center.y
} else {
n.center.x
}
};
let span = if vertical { a.height } else { a.width };
assert!(
flow(&a, head) < span / 2.0 && flow(&b, head) > span / 2.0,
"{name}: {head} is the source's own first node — {forward} puts it in the near \
half of a {span}px diagram (at {}) and {reverse} must put it in the far half, \
not at {}",
flow(&a, head),
flow(&b, head)
);
}
}
}
/// A rule §10 states about the **cross** axis is stated in absolute screen terms and must
/// therefore *not* mirror: §10-5 S3's own self-transition face ("`LR`: 上辺"), §10-3 item 11's own
/// "非幹の枝は上から宣言順", and `orthogonal::place_dead_end_tiers`' own "the emptier side".
///
/// [`assert_mirrored_diagrams`] already implies this (a flow-axis reflection leaves the cross axis
/// alone, and it checks every cross coordinate), but only as a consequence. Saying it directly is
/// what would fail loudly if the mirror were ever widened into a point reflection or a rotation —
/// which is the shape a "just flip both axes" reading of `RL` would take, and which would silently
/// put the tier on the wrong side and reverse the fan's own declaration order.
#[test]
fn orthogonal_mirroring_the_flow_axis_leaves_the_cross_axis_alone() {
let lr = laid_out_flow(
&flowchart_with_direction(FAN_MERGE_ASIDE_TIER, "LR"),
"basis",
"konoma-orthogonal",
);
let rl = laid_out_flow(
&flowchart_with_direction(FAN_MERGE_ASIDE_TIER, "RL"),
"basis",
"konoma-orthogonal",
);
let cross = |d: &Diagram, id: &str| {
d.nodes
.iter()
.find(|n| n.id == id)
.unwrap_or_else(|| panic!("{id} is a node of the fixture"))
.center
.y
};
// The fan's own five branches, in declaration order, and the tier's own two members: both
// groups' cross-axis order is a rule about the screen, not about the flow.
for id in ["B1", "B2", "B3", "B4", "B5", "T1", "T2"] {
assert!(
(cross(&lr, id) - cross(&rl, id)).abs() < MIRROR_EPS,
"{id} sits at y {} under LR and y {} under RL — the cross axis is not mirrored",
cross(&lr, id),
cross(&rl, id)
);
}
let tier_side = |d: &Diagram| cross(d, "T1") > cross(d, "M");
assert_eq!(
tier_side(&lr),
tier_side(&rl),
"the dead-end tier hangs off the same side of the trunk in both directions"
);
}
/// [`super::mirror_flow_axis`] on its own, over a hand-built diagram — no font, no layout, and one
/// of every piece of geometry the function has to carry.
///
/// The corpus tests above state the *property*; this states the **coverage**. A mirror that forgot
/// `PlacedEdge::gaps`, or an edge's `start_label`/`end_label`/`badge`, would still pass every
/// mirror assertion over a flowchart source — no flowchart edge carries the last three, and a
/// crossing gap only appears in a diagram busy enough to have one. `super::normalise` already had
/// exactly this hole once (its own doc records `gaps` being left pointing at the pre-translation
/// location), and it is the same list, so it is the same hole.
#[test]
fn mirror_flow_axis_reflects_every_piece_of_geometry_and_only_for_bt_and_rl() {
let built = || {
let mut edge = bent_edge(
vec![Point::new(10.0, 20.0), Point::new(30.0, 40.0)],
Curve::Basis,
);
edge.gaps = vec![(Point::new(12.0, 22.0), Point::new(18.0, 28.0))];
let plate = |x: f64, y: f64| PlacedEdgeLabel {
center: Point::new(x, y),
size: Size::new(8.0, 4.0),
label: Label::measure(""),
};
edge.label = Some(plate(50.0, 60.0));
edge.start_label = Some(plate(52.0, 62.0));
edge.end_label = Some(plate(54.0, 64.0));
edge.badge = Some(plate(56.0, 66.0));
Diagram {
width: 0.0,
height: 0.0,
nodes: vec![placed_node("n", 100.0, 200.0, 40.0, 20.0)],
clusters: vec![PlacedCluster {
id: "c".to_string(),
title: Label::measure(""),
center: Point::new(300.0, 400.0),
size: Size::new(60.0, 30.0),
parent: None,
depth: 0,
dashed: false,
filled: true,
sections: Vec::new(),
title_strip: false,
}],
edges: vec![edge],
lifelines: Vec::new(),
}
};
for direction in [Direction::LeftToRight, Direction::TopToBottom] {
let mut d = built();
super::mirror_flow_axis(&mut d, direction);
assert_eq!(
d,
built(),
"{direction:?} is already the canonical orientation: the mirror must not touch it"
);
}
// Every coordinate on the flow axis negated, every coordinate across it left alone. Listed as
// whole points rather than checked with a loop, so a piece of geometry the function forgets is
// a failing assertion and not a silently shorter list.
let mut rl = built();
super::mirror_flow_axis(&mut rl, Direction::RightToLeft);
assert_eq!(rl.nodes[0].center, Point::new(-100.0, 200.0));
assert_eq!(
rl.nodes[0].size,
Size::new(40.0, 20.0),
"sizes do not reflect"
);
assert_eq!(rl.clusters[0].center, Point::new(-300.0, 400.0));
assert_eq!(
rl.edges[0].points,
vec![Point::new(-10.0, 20.0), Point::new(-30.0, 40.0)]
);
assert_eq!(
rl.edges[0].gaps,
vec![(Point::new(-12.0, 22.0), Point::new(-18.0, 28.0))]
);
for (what, plate) in [
("label", &rl.edges[0].label),
("start_label", &rl.edges[0].start_label),
("end_label", &rl.edges[0].end_label),
("badge", &rl.edges[0].badge),
] {
let plate = plate.as_ref().unwrap_or_else(|| panic!("{what} survives"));
assert!(
plate.center.x < 0.0 && plate.center.y > 0.0,
"{what} sits at {:?}: its flow coordinate is reflected and its cross one is not",
plate.center
);
}
let mut bt = built();
super::mirror_flow_axis(&mut bt, Direction::BottomToTop);
assert_eq!(bt.nodes[0].center, Point::new(100.0, -200.0));
assert_eq!(bt.clusters[0].center, Point::new(300.0, -400.0));
assert_eq!(
bt.edges[0].points,
vec![Point::new(10.0, -20.0), Point::new(30.0, -40.0)]
);
assert_eq!(
bt.edges[0].gaps,
vec![(Point::new(12.0, -22.0), Point::new(18.0, -28.0))]
);
}
/// A self-loop stays on its **own** node's box in every one of the four directions — the half of
/// the direction bug that was not a plain mirror.
///
/// `pull_back_fan_ranks` rewrites every *node*'s flow coordinate, so the nodes came out canonical
/// under `BT`/`RL` all along; dagre's own edge waypoints did not, and a self-loop is the one shape
/// still drawn from them (`orthogonal::route_staircase_with_ports`). The two therefore disagreed by
/// the whole diagram's flow extent: on the `self-loop` corpus source laid out `BT`, `A --> A` was
/// drawn spanning y 88-130 while `A` sat at y 26 — a loop around `B`. Stated with a bound tight
/// enough that a loop attached to the *next* node along the flow cannot pass, which is what the
/// corpus-wide "no dangling fragment" check catches only incidentally.
#[test]
fn orthogonal_a_self_loop_hugs_its_own_node_in_every_direction() {
// The loop bumps `SELF_LOOP_BUMP` px clear of the face plus its own label room; one rank gap
// (`RANK_SEP`, 50px) is the distance to the next node, and anything under it is unambiguously
// "on its own box".
const BUMP_MARGIN: f64 = 45.0;
let src = "flowchart LR\n A --> A\n A --> B\n B --> C";
for direction in ["LR", "RL", "TB", "BT"] {
let d = laid_out_flow(
&flowchart_with_direction(src, direction),
"basis",
"konoma-orthogonal",
);
let loop_edge = d
.edges
.iter()
.find(|e| e.from == "A" && e.to == "A")
.unwrap_or_else(|| panic!("{direction}: the self-loop must still be drawn"));
let (l, t, r, b) = d
.nodes
.iter()
.find(|n| n.id == "A")
.expect("A is a node")
.bounds();
for p in &loop_edge.points {
assert!(
p.x >= l - BUMP_MARGIN
&& p.x <= r + BUMP_MARGIN
&& p.y >= t - BUMP_MARGIN
&& p.y <= b + BUMP_MARGIN,
"{direction}: A's self-loop runs through {p:?}, which is more than {BUMP_MARGIN}px \
outside A's own box ({l},{t})-({r},{b}) — the loop is drawn from dagre's own \
waypoints, so this is what a waypoint left in the un-canonicalised space looks like"
);
}
}
}