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asbuilt_core/
emit.rs

1//! The LikeC4 emitter: a [`Model`] to the text of one `.c4` file.
2//!
3//! This is the only place LikeC4 syntax is produced. The facts it relies
4//! on were verified against the LikeC4 release the CLI pins, and the CLI's `likec4_` tests
5//! run every emitted shape through the real parser. Output is a pure
6//! function of the normalized model: same model, same bytes, on every
7//! platform.
8
9use std::collections::{BTreeMap, BTreeSet};
10use std::fmt::Write;
11
12use crate::model::{Element, Id, Model, RelationKind, sanitize_id, sanitize_segment};
13
14/// The first line of every generated file. No version in it: a version
15/// would turn every asbuilt release into drift in every consumer.
16pub const HEADER: &str = "// GENERATED by asbuilt. Do not edit; run asbuilt survey.";
17
18/// How the file relates to the repo it describes.
19#[derive(Debug, Clone, PartialEq, Eq)]
20pub struct EmitOptions {
21    /// The prefix that takes a `link` from the output file's directory
22    /// back to the surveyed root: `../../` for `docs/architecture/x.c4`,
23    /// `./` for a file at the root.
24    pub link_prefix: String,
25    /// The color per element kind (`container`, `component`, an external
26    /// kind), declared in the specification and applied as that kind's
27    /// style. Kinds absent here get LikeC4's default.
28    pub theme: BTreeMap<String, String>,
29}
30
31impl EmitOptions {
32    /// Options for a file written at `output_path`, relative to the root
33    /// and `/`-separated.
34    pub fn for_output_path(output_path: &str) -> Self {
35        let depth = output_path
36            .split('/')
37            .filter(|s| !s.is_empty() && *s != ".")
38            .count()
39            .saturating_sub(1);
40        let link_prefix = if depth == 0 {
41            "./".to_string()
42        } else {
43            "../".repeat(depth)
44        };
45        Self {
46            link_prefix,
47            theme: BTreeMap::new(),
48        }
49    }
50
51    /// The same options with a theme.
52    pub fn with_theme(mut self, theme: BTreeMap<String, String>) -> Self {
53        self.theme = theme;
54        self
55    }
56}
57
58/// A LikeC4 single-quoted string. `\` and `'` are escaped; newlines
59/// pass through, since a single-quoted string may span lines.
60fn quote(text: &str) -> String {
61    let mut out = String::with_capacity(text.len() + 2);
62    out.push('\'');
63    for c in text.chars() {
64        match c {
65            '\\' => out.push_str("\\\\"),
66            '\'' => out.push_str("\\'"),
67            '\r' => {}
68            c => out.push(c),
69        }
70    }
71    out.push('\'');
72    out
73}
74
75/// A path as a LikeC4 link target, which is an unquoted URI: every byte
76/// outside the unreserved set and `/` is percent-encoded, so a space
77/// or a quote in a directory name cannot break the parse.
78pub fn link_encode(path: &str) -> String {
79    let mut out = String::with_capacity(path.len());
80    for byte in path.bytes() {
81        let keep = byte.is_ascii_alphanumeric() || matches!(byte, b'-' | b'.' | b'_' | b'~' | b'/');
82        if keep {
83            out.push(byte as char);
84        } else {
85            out.push_str(&format!("%{byte:02X}"));
86        }
87    }
88    out
89}
90
91/// The `.c4` text for `model`. The model is normalized on a copy first,
92/// so the caller's element order does not matter.
93pub fn emit(model: &Model, options: &EmitOptions) -> String {
94    let mut model = model.clone();
95    model.normalize();
96
97    let mut out = String::new();
98    out.push_str(HEADER);
99    out.push('\n');
100    out.push('\n');
101    emit_specification(&mut out, &model, &options.theme);
102    out.push('\n');
103    emit_model(&mut out, &model, options);
104    out.push('\n');
105    emit_views(&mut out, &model);
106    out
107}
108
109/// The name of a themed kind's color in the specification.
110pub fn theme_color_name(kind: &str) -> String {
111    format!("theme_{kind}")
112}
113
114fn emit_specification(out: &mut String, model: &Model, theme: &BTreeMap<String, String>) {
115    let mut kinds: BTreeSet<&str> = BTreeSet::new();
116    let mut tags: BTreeSet<&str> = BTreeSet::new();
117    for element in &model.elements {
118        kinds.insert(element.kind.keyword());
119        tags.extend(element.tags.iter().map(String::as_str));
120    }
121    out.push_str("specification {\n");
122    for kind in &kinds {
123        if let Some(color) = theme.get(*kind) {
124            writeln!(out, "  color {} {color}", theme_color_name(kind)).unwrap();
125        }
126    }
127    for kind in &kinds {
128        if theme.contains_key(*kind) {
129            writeln!(
130                out,
131                "  element {kind} {{\n    style {{\n      color {}\n    }}\n  }}",
132                theme_color_name(kind)
133            )
134            .unwrap();
135        } else {
136            writeln!(out, "  element {kind}").unwrap();
137        }
138    }
139    for tag in tags {
140        writeln!(out, "  tag {tag}").unwrap();
141    }
142    for kind in RelationKind::ALL {
143        writeln!(out, "  relationship {}", kind.keyword()).unwrap();
144    }
145    out.push_str("}\n");
146}
147
148/// Elements whose parent id is `parent` (or every top-level element when
149/// `parent` is empty). "Top-level" means no element in the model has the
150/// id one segment shorter, so an orphan component still gets emitted.
151pub(crate) fn children_of<'a>(model: &'a Model, parent: &[String]) -> Vec<&'a Element> {
152    model
153        .elements
154        .iter()
155        .filter(|e| {
156            if parent.is_empty() {
157                e.id.len() == 1 || model.element(&e.id[..e.id.len() - 1]).is_none()
158            } else {
159                e.id.len() == parent.len() + 1 && e.id.starts_with(parent)
160            }
161        })
162        .collect()
163}
164
165fn emit_model(out: &mut String, model: &Model, options: &EmitOptions) {
166    out.push_str("model {\n");
167    for element in children_of(model, &[]) {
168        emit_element(out, model, element, options, 1);
169    }
170    if !model.relations.is_empty() {
171        out.push('\n');
172    }
173    for rel in &model.relations {
174        let indent = "  ";
175        write!(
176            out,
177            "{indent}{} -[{}]-> {}",
178            sanitize_id(&rel.source),
179            rel.kind.keyword(),
180            sanitize_id(&rel.target)
181        )
182        .unwrap();
183        if !rel.items.is_empty() {
184            write!(out, " {}", quote(&rel.items.join(", "))).unwrap();
185        }
186        match &rel.technology {
187            Some(technology) => {
188                writeln!(
189                    out,
190                    " {{\n{indent}  technology {}\n{indent}}}",
191                    quote(technology)
192                )
193                .unwrap();
194            }
195            None => out.push('\n'),
196        }
197    }
198    out.push_str("}\n");
199}
200
201fn emit_element(
202    out: &mut String,
203    model: &Model,
204    element: &Element,
205    options: &EmitOptions,
206    depth: usize,
207) {
208    let indent = "  ".repeat(depth);
209    let inner = "  ".repeat(depth + 1);
210    // Only the last segment is written; nesting supplies the rest of the
211    // fully qualified id. An element whose parent is not in the model
212    // lands at the top level under its last segment, and any reference
213    // to its full id then fails `likec4 validate`, which is the right
214    // signal for a front-end that forgot the parent.
215    let name = sanitize_segment(element.id.last().map(String::as_str).unwrap_or_default());
216    let children = children_of(model, &element.id);
217    let has_body = !element.tags.is_empty()
218        || element.description.is_some()
219        || element.technology.is_some()
220        || element.path.is_some()
221        || !children.is_empty();
222
223    write!(
224        out,
225        "{indent}{name} = {} {}",
226        element.kind.keyword(),
227        quote(&element.title)
228    )
229    .unwrap();
230    if !has_body {
231        out.push('\n');
232        return;
233    }
234    out.push_str(" {\n");
235    // Tags must come first in the body.
236    if !element.tags.is_empty() {
237        let tags: Vec<String> = element.tags.iter().map(|t| format!("#{t}")).collect();
238        writeln!(out, "{inner}{}", tags.join(" ")).unwrap();
239    }
240    if let Some(description) = &element.description {
241        writeln!(out, "{inner}description {}", quote(description)).unwrap();
242    }
243    if let Some(technology) = &element.technology {
244        writeln!(out, "{inner}technology {}", quote(technology)).unwrap();
245    }
246    if let Some(path) = &element.path {
247        writeln!(
248            out,
249            "{inner}metadata {{\n{inner}  path {}\n{inner}}}",
250            quote(path)
251        )
252        .unwrap();
253        // The surveyed root itself has no link: likec4 rejects a link
254        // that is only a prefix (`./`), and the file's own directory
255        // needs no link to be found.
256        if path != "." {
257            writeln!(
258                out,
259                "{inner}link {}{}",
260                options.link_prefix,
261                link_encode(path)
262            )
263            .unwrap();
264        }
265    }
266    for child in children {
267        emit_element(out, model, child, options, depth + 1);
268    }
269    writeln!(out, "{indent}}}").unwrap();
270}
271
272/// The base view id for an element: its sanitized id with `_` for `.`.
273/// Two elements can share one (`a.b_c` and `a_b.c`); [`view_ids`] is
274/// where the later one gets its suffix.
275pub fn view_id(id: &Id) -> String {
276    format!("view_{}", sanitize_id(id).replace('.', "_"))
277}
278
279/// The generated view of every element with children, keyed by element
280/// id: the view name as the emitter declares it and as `asbuilt render`
281/// names the SVG. Where two ids collapse to one base name, the second
282/// and later take a numeric suffix in element order, so the names are
283/// stable for a normalized model (`emit` normalizes first; call this on
284/// the same model to get the same names).
285pub fn view_ids(model: &Model) -> BTreeMap<Id, String> {
286    let mut used: BTreeSet<String> = BTreeSet::from(["index".to_string()]);
287    let mut names = BTreeMap::new();
288    for element in &model.elements {
289        if children_of(model, &element.id).is_empty() {
290            continue;
291        }
292        let base = view_id(&element.id);
293        let id = std::iter::once(base.clone())
294            .chain((2..).map(|n| format!("{base}_{n}")))
295            .find(|candidate| used.insert(candidate.clone()))
296            .expect("an unbounded sequence of candidates always has a free one");
297        names.insert(element.id.clone(), id);
298    }
299    names
300}
301
302fn emit_views(out: &mut String, model: &Model) {
303    out.push_str("views {\n");
304    let top: Vec<String> = children_of(model, &[])
305        .iter()
306        .map(|e| sanitize_id(&e.id))
307        .collect();
308    out.push_str("  view index {\n    title 'Overview'\n");
309    if !top.is_empty() {
310        writeln!(out, "    include {}", top.join(", ")).unwrap();
311    }
312    out.push_str("    autoLayout LeftRight\n  }\n");
313    let names = view_ids(model);
314    for element in &model.elements {
315        let Some(id) = names.get(&element.id) else {
316            continue;
317        };
318        let fqn = sanitize_id(&element.id);
319        writeln!(
320            out,
321            "\n  view {id} of {fqn} {{\n    title {}\n    include *\n    autoLayout TopBottom\n  }}",
322            quote(&element.id.join("."))
323        )
324        .unwrap();
325    }
326    out.push_str("}\n");
327}
328
329#[cfg(test)]
330mod tests {
331    use super::*;
332    use crate::model::{ElementKind, Relation};
333
334    fn id(s: &str) -> Id {
335        s.split('.').map(str::to_string).collect()
336    }
337
338    fn element(s: &str, kind: ElementKind) -> Element {
339        Element {
340            id: id(s),
341            kind,
342            title: s.rsplit('.').next().unwrap().to_string(),
343            description: None,
344            technology: None,
345            path: None,
346            tags: vec![],
347        }
348    }
349
350    fn sample() -> Model {
351        let mut app = element("app", ElementKind::Container);
352        app.technology = Some("library crate".into());
353        app.path = Some("crates/app".into());
354        let mut server = element("app.server", ElementKind::Component);
355        server.description = Some("Where it's sent.\n\n- one\n- two".into());
356        server.path = Some("crates/app/src/server.rs".into());
357        let mut tests = element("app.tests", ElementKind::Tests);
358        tests.tags = vec!["tests".into()];
359        let mut driver = element("node_driver", ElementKind::External("process".into()));
360        driver.tags = vec!["external".into()];
361        driver.technology = Some("Node.js process".into());
362        Model {
363            elements: vec![tests, driver, server, app],
364            relations: vec![
365                Relation {
366                    source: id("app.tests"),
367                    target: id("app.server"),
368                    kind: RelationKind::Calls,
369                    items: vec!["Server".into(), "connect".into()],
370                    technology: None,
371                },
372                Relation {
373                    source: id("app.server"),
374                    target: id("node_driver"),
375                    kind: RelationKind::Uses,
376                    items: vec!["spawns".into()],
377                    technology: Some("stdio".into()),
378                },
379            ],
380            ..Default::default()
381        }
382    }
383
384    fn options() -> EmitOptions {
385        EmitOptions::for_output_path("docs/architecture/model.c4")
386    }
387
388    #[test]
389    fn the_header_is_the_first_line() {
390        let text = emit(&sample(), &options());
391        assert_eq!(text.lines().next(), Some(HEADER));
392    }
393
394    #[test]
395    fn the_specification_declares_every_element_kind_tag_and_relationship_kind() {
396        let text = emit(&sample(), &options());
397        let spec = text.split("model {").next().unwrap();
398        for line in [
399            "  element component",
400            "  element container",
401            "  element process",
402            "  element tests",
403            "  tag external",
404            "  tag tests",
405            "  relationship implements",
406            "  relationship constructs",
407            "  relationship calls",
408            "  relationship names",
409            "  relationship uses",
410        ] {
411            assert!(
412                spec.contains(&format!("{line}\n")),
413                "missing {line:?} in:\n{spec}"
414            );
415        }
416    }
417
418    #[test]
419    fn a_themed_kind_declares_its_color_and_styles_the_element_with_it() {
420        let opts = options().with_theme(BTreeMap::from([
421            ("container".to_string(), "#f0a884".to_string()),
422            ("process".to_string(), "#c9c9c9".to_string()),
423        ]));
424        let text = emit(&sample(), &opts);
425        let spec = text.split("model {").next().unwrap();
426        assert!(
427            spec.starts_with(&format!(
428                "{HEADER}\n\nspecification {{\n  color theme_container #f0a884\n  color theme_process #c9c9c9\n  element component\n  element container {{\n    style {{\n      color theme_container\n    }}\n  }}\n  element process {{\n    style {{\n      color theme_process\n    }}\n  }}\n  element tests\n  tag external\n"
429            )),
430            "{spec}"
431        );
432    }
433
434    #[test]
435    fn a_theme_for_a_kind_the_model_lacks_emits_nothing_for_it() {
436        let opts = options().with_theme(BTreeMap::from([(
437            "browser".to_string(),
438            "#000000".to_string(),
439        )]));
440        let text = emit(&sample(), &opts);
441        assert!(!text.contains("browser"), "{text}");
442        assert_eq!(text, emit(&sample(), &options()));
443    }
444
445    #[test]
446    fn a_child_is_nested_inside_its_parent_under_its_last_segment() {
447        let text = emit(&sample(), &options());
448        let app_block = text.split("  app = container 'app' {").nth(1).unwrap();
449        assert!(
450            app_block.contains("\n    server = component 'server' {"),
451            "{text}"
452        );
453        assert!(!text.contains("app.server = component"), "{text}");
454    }
455
456    #[test]
457    fn tags_come_first_in_a_body() {
458        let text = emit(&sample(), &options());
459        assert!(
460            text.contains("tests = tests 'tests' {\n      #tests\n    }"),
461            "{text}"
462        );
463    }
464
465    #[test]
466    fn a_quote_in_a_description_is_escaped_and_markdown_kept() {
467        let text = emit(&sample(), &options());
468        assert!(
469            text.contains("description 'Where it\\'s sent.\n\n- one\n- two'"),
470            "{text}"
471        );
472    }
473
474    #[test]
475    fn a_path_becomes_metadata_and_a_link_relative_to_the_output_directory() {
476        let text = emit(&sample(), &options());
477        assert!(text.contains("metadata {\n        path 'crates/app/src/server.rs'\n      }\n      link ../../crates/app/src/server.rs\n"), "{text}");
478    }
479
480    #[test]
481    fn an_output_file_at_the_root_links_with_a_dot_prefix() {
482        let text = emit(&sample(), &EmitOptions::for_output_path("model.c4"));
483        assert!(text.contains("link ./crates/app\n"), "{text}");
484        assert_eq!(EmitOptions::for_output_path("./model.c4").link_prefix, "./");
485    }
486
487    #[test]
488    fn a_relation_line_carries_kind_label_and_technology() {
489        let text = emit(&sample(), &options());
490        assert!(
491            text.contains("  app.tests -[calls]-> app.server 'Server, connect'\n"),
492            "{text}"
493        );
494        assert!(
495            text.contains(
496                "  app.server -[uses]-> node_driver 'spawns' {\n    technology 'stdio'\n  }\n"
497            ),
498            "{text}"
499        );
500    }
501
502    #[test]
503    fn a_relation_without_items_has_no_label() {
504        let mut model = sample();
505        model.relations[0].items.clear();
506        let text = emit(&model, &options());
507        assert!(
508            text.contains("  app.tests -[calls]-> app.server\n"),
509            "{text}"
510        );
511    }
512
513    #[test]
514    fn the_index_view_includes_every_top_level_element() {
515        let text = emit(&sample(), &options());
516        assert!(text.contains("  view index {\n    title 'Overview'\n    include app, node_driver\n    autoLayout LeftRight\n  }"), "{text}");
517    }
518
519    #[test]
520    fn an_element_with_children_gets_a_scoped_view_and_a_leaf_does_not() {
521        let text = emit(&sample(), &options());
522        assert!(text.contains("  view view_app of app {\n    title 'app'\n    include *\n    autoLayout TopBottom\n  }"), "{text}");
523        assert!(!text.contains("of app.server {"), "{text}");
524        assert!(!text.contains("of node_driver {"), "{text}");
525    }
526
527    #[test]
528    fn a_hyphen_in_an_id_is_an_underscore_everywhere_it_appears() {
529        let mut model = sample();
530        for e in &mut model.elements {
531            if e.id[0] == "app" {
532                e.id[0] = "my-app".into();
533            }
534        }
535        for r in &mut model.relations {
536            if r.source[0] == "app" {
537                r.source[0] = "my-app".into();
538            }
539            if r.target[0] == "app" {
540                r.target[0] = "my-app".into();
541            }
542        }
543        let text = emit(&model, &options());
544        assert!(text.contains("  my_app = container"), "{text}");
545        assert!(
546            text.contains("my_app.tests -[calls]-> my_app.server"),
547            "{text}"
548        );
549        assert!(text.contains("view view_my_app of my_app"), "{text}");
550        // The raw name survives only inside a quoted title.
551        for line in text.lines().filter(|l| l.contains("my-app")) {
552            assert!(line.trim_start().starts_with("title "), "{line}");
553        }
554    }
555
556    #[test]
557    fn an_element_whose_parent_is_absent_is_emitted_at_the_top_level() {
558        let model = Model {
559            elements: vec![element("gone.child", ElementKind::Component)],
560            ..Default::default()
561        };
562        let text = emit(&model, &options());
563        assert!(
564            text.contains("model {\n  child = component 'child'\n"),
565            "{text}"
566        );
567    }
568
569    #[test]
570    fn each_body_field_alone_earns_a_block() {
571        fn only(f: impl FnOnce(&mut Element)) -> Model {
572            let mut e = element("x", ElementKind::Container);
573            f(&mut e);
574            Model {
575                elements: vec![e],
576                ..Default::default()
577            }
578        }
579        let mut with_child = only(|_| {});
580        with_child
581            .elements
582            .push(element("x.y", ElementKind::Component));
583        let cases = [
584            ("tags", only(|e| e.tags = vec!["tests".into()])),
585            ("description", only(|e| e.description = Some("d".into()))),
586            ("technology", only(|e| e.technology = Some("t".into()))),
587            ("path", only(|e| e.path = Some("p".into()))),
588            ("child", with_child),
589        ];
590        for (field, model) in cases {
591            let text = emit(&model, &options());
592            assert!(
593                text.contains("  x = container 'x' {\n"),
594                "{field} alone should open a block:\n{text}"
595            );
596        }
597    }
598
599    #[test]
600    fn an_element_with_nothing_to_say_has_no_block() {
601        let model = Model {
602            elements: vec![element("leaf", ElementKind::Container)],
603            ..Default::default()
604        };
605        let text = emit(&model, &options());
606        assert!(text.contains("  leaf = container 'leaf'\n}"), "{text}");
607    }
608
609    #[test]
610    fn output_does_not_depend_on_input_order() {
611        let a = emit(&sample(), &options());
612        let mut shuffled = sample();
613        shuffled.elements.reverse();
614        shuffled.relations.reverse();
615        let b = emit(&shuffled, &options());
616        assert_eq!(a, b);
617    }
618
619    #[test]
620    fn output_has_no_carriage_returns_or_backslashes_in_paths() {
621        let mut model = sample();
622        model.elements[2].description = Some("line\r\nnext".into());
623        let text = emit(&model, &options());
624        assert!(!text.contains('\r'), "{text:?}");
625        assert!(text.contains("description 'line\nnext'"), "{text}");
626    }
627
628    #[test]
629    fn the_root_path_keeps_its_metadata_but_has_no_link() {
630        let mut model = sample();
631        model
632            .elements
633            .iter_mut()
634            .find(|e| e.id == ["app"])
635            .unwrap()
636            .path = Some(".".into());
637        let text = emit(&model, &options());
638        let app_block = text.split("  app = container 'app' {").nth(1).unwrap();
639        let head: String = app_block.lines().take(4).collect::<Vec<_>>().join("\n");
640        assert!(head.contains("path '.'"), "{head}");
641        assert!(!head.contains("link"), "{head}");
642    }
643
644    #[test]
645    fn a_space_or_quote_in_a_path_is_percent_encoded_in_the_link_only() {
646        let mut model = sample();
647        model
648            .elements
649            .iter_mut()
650            .find(|e| e.id == ["app", "server"])
651            .unwrap()
652            .path = Some("crates/my tool/it's.rs".into());
653        let text = emit(&model, &options());
654        assert!(text.contains("path 'crates/my tool/it\\'s.rs'"), "{text}");
655        assert!(
656            text.contains("link ../../crates/my%20tool/it%27s.rs\n"),
657            "{text}"
658        );
659    }
660
661    #[test]
662    fn link_encoding_keeps_unreserved_characters_and_slashes() {
663        assert_eq!(link_encode("a-b_c.d~/e"), "a-b_c.d~/e");
664        assert_eq!(link_encode("é"), "%C3%A9");
665    }
666
667    #[test]
668    fn two_ids_that_collapse_to_one_view_id_get_distinct_views() {
669        let model = Model {
670            elements: vec![
671                element("a.b_c", ElementKind::Container),
672                element("a.b_c.x", ElementKind::Component),
673                element("a_b.c", ElementKind::Container),
674                element("a_b.c.y", ElementKind::Component),
675                element("a_b_c", ElementKind::Container),
676                element("a_b_c.z", ElementKind::Component),
677            ],
678            ..Default::default()
679        };
680        let text = emit(&model, &options());
681        assert!(text.contains("view view_a_b_c of a.b_c {"), "{text}");
682        assert!(text.contains("view view_a_b_c_2 of a_b.c {"), "{text}");
683        assert!(text.contains("view view_a_b_c_3 of a_b_c {"), "{text}");
684        let mut normalized = model.clone();
685        normalized.normalize();
686        let names: Vec<String> = view_ids(&normalized).into_values().collect();
687        assert_eq!(names, ["view_a_b_c", "view_a_b_c_2", "view_a_b_c_3"]);
688    }
689
690    #[test]
691    fn view_ids_names_every_element_with_children_and_only_those() {
692        let mut model = sample();
693        model.normalize();
694        let names = view_ids(&model);
695        let keyed: Vec<(String, String)> = names
696            .iter()
697            .map(|(id, name)| (id.join("."), name.clone()))
698            .collect();
699        assert_eq!(keyed, [("app".to_string(), "view_app".to_string())]);
700        assert!(!names.contains_key(&id("app.server")));
701        assert!(!names.contains_key(&id("node_driver")));
702    }
703
704    #[test]
705    fn a_backslash_in_a_string_is_escaped() {
706        assert_eq!(quote("a\\b"), "'a\\\\b'");
707    }
708
709    #[test]
710    fn link_prefix_counts_directories_not_the_file() {
711        assert_eq!(
712            EmitOptions::for_output_path("a/b/c/m.c4").link_prefix,
713            "../../../"
714        );
715        assert_eq!(EmitOptions::for_output_path("a/m.c4").link_prefix, "../");
716    }
717}