fallow_extract/
sfc.rs

1//! Vue/Svelte Single File Component (SFC) script and style extraction.
2//!
3//! Extracts `<script>` block content from `.vue` and `.svelte` files using regex,
4//! handling `lang`, `src` metadata, and `generic` attributes, and filtering
5//! HTML comments. Vue external script references are emitted as graph edges;
6//! Svelte markup-level script `src` references are treated as runtime HTML.
7//! Also extracts `<style>` block sources (`@import` / `@use` / `@forward` /
8//! `@plugin` and `<style src="...">`) so referenced CSS / SCSS files become
9//! reachable from the component, preventing false `unused-files` reports on
10//! co-located styles.
11
12use std::path::Path;
13use std::sync::LazyLock;
14
15use oxc_allocator::Allocator;
16use oxc_ast_visit::Visit;
17use oxc_parser::Parser;
18use oxc_span::SourceType;
19use rustc_hash::{FxHashMap, FxHashSet};
20
21use crate::asset_url::normalize_asset_url;
22use crate::parse::{
23    compute_auto_import_candidates, compute_import_binding_usage, compute_semantic_usage,
24};
25use crate::sfc_template::{SfcKind, collect_template_usage_with_bound_targets};
26use crate::source_map::ExtractionResult;
27use crate::visitor::ModuleInfoExtractor;
28use crate::{ImportInfo, ImportedName, ModuleInfo};
29use fallow_types::discover::FileId;
30use fallow_types::extract::{FunctionComplexity, byte_offset_to_line_col, compute_line_offsets};
31use oxc_span::Span;
32
33/// Regex to extract `<script>` block content from Vue/Svelte SFCs.
34/// The attrs pattern handles `>` inside quoted attribute values (e.g., `generic="T extends Foo<Bar>"`).
35static SCRIPT_BLOCK_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
36    crate::static_regex(
37        r#"(?is)<script\b(?P<attrs>(?:[^>"']|"[^"]*"|'[^']*')*)>(?P<body>[\s\S]*?)</script>"#,
38    )
39});
40
41/// Regex to extract the `lang` attribute value from a script tag.
42static LANG_ATTR_RE: LazyLock<regex::Regex> =
43    LazyLock::new(|| crate::static_regex(r#"lang\s*=\s*["'](\w+)["']"#));
44
45/// Regex to extract the `src` attribute value from a script tag.
46/// Requires whitespace (or start of string) before `src` to avoid matching `data-src` etc.
47static SRC_ATTR_RE: LazyLock<regex::Regex> =
48    LazyLock::new(|| crate::static_regex(r#"(?:^|\s)src\s*=\s*["']([^"']+)["']"#));
49
50/// Regex to detect Vue's bare `setup` attribute.
51static SETUP_ATTR_RE: LazyLock<regex::Regex> =
52    LazyLock::new(|| crate::static_regex(r"(?:^|\s)setup(?:\s|$)"));
53
54/// Regex to detect Svelte's `context="module"` attribute (Svelte 4).
55static CONTEXT_MODULE_ATTR_RE: LazyLock<regex::Regex> =
56    LazyLock::new(|| crate::static_regex(r#"context\s*=\s*["']module["']"#));
57
58/// Regex to detect Svelte 5's bare `module` script attribute (`<script module>`,
59/// `<script module lang="ts">`). Anchored like [`SETUP_ATTR_RE`] so `module` must
60/// be a standalone attribute, not a substring of another attr name (e.g.
61/// `data-module`) or value.
62static SVELTE_MODULE_ATTR_RE: LazyLock<regex::Regex> =
63    LazyLock::new(|| crate::static_regex(r"(?:^|\s)module(?:\s|$|=)"));
64
65/// Regex to extract Vue's `generic="..."` attribute value (script-setup
66/// generics). Matches the contents between the quotes and stops at the
67/// closing quote, mirroring `LANG_ATTR_RE`.
68static VUE_GENERIC_ATTR_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
69    crate::static_regex(r#"(?:^|\s)generic\s*=\s*"([^"]*)"|(?:^|\s)generic\s*=\s*'([^']*)'"#)
70});
71
72/// Regex to extract Svelte's `generics="..."` attribute value (Svelte 4
73/// generic script attribute, repurposed by some Svelte 5 code).
74static SVELTE_GENERICS_ATTR_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
75    crate::static_regex(r#"(?:^|\s)generics\s*=\s*"([^"]*)"|(?:^|\s)generics\s*=\s*'([^']*)'"#)
76});
77
78/// Regex to match HTML comments for filtering script blocks inside comments.
79static HTML_COMMENT_RE: LazyLock<regex::Regex> =
80    LazyLock::new(|| crate::static_regex(r"(?s)<!--.*?-->"));
81
82/// Regex to detect a whole-object prop/attr spread in a Vue template:
83/// `v-bind="$attrs"`, `v-bind="$props"`, or `v-bind="props"` (with single or
84/// double quotes). A bound prop may be consumed indirectly, so the
85/// `unused-component-prop` detector abstains on the whole file when this matches.
86static PROPS_ATTRS_SPREAD_RE: LazyLock<regex::Regex> =
87    LazyLock::new(|| crate::static_regex(r#"v-bind\s*=\s*["'](?:\$attrs|\$props|props)["']"#));
88
89/// FP-1 (unused-load-data-key): a SvelteKit route component passing the whole
90/// `data` prop opaquely in MARKUP, where a child reads arbitrary keys the
91/// detector cannot see. Matches `data={data}` (whole-prop pass to a child) and
92/// `{...data}` (Svelte template spread). The script-side `const x = {...data}` /
93/// `fn(data)` / `const X = data` forms are captured by the JS visitor instead.
94/// Only a whole-`data` pass forces the abstain; `data.x` member access stays a
95/// credited consumer.
96static SVELTE_TEMPLATE_DATA_WHOLE_USE_RE: LazyLock<regex::Regex> =
97    LazyLock::new(|| crate::static_regex(r"(?:=\s*\{\s*data\s*\}|\{\s*\.\.\.\s*data\s*\})"));
98
99/// Matches an emit-style call in template markup: a callee identifier (or
100/// `$emit`) followed by `(` and its first argument. Group 1 is the callee name
101/// (filtered against the harvested emit binding / `$emit` by the caller), groups
102/// 2 and 3 are a string-literal first arg (single- or double-quoted: the event
103/// name, credited as used), and group 4 is the first non-space character of a
104/// NON-literal first arg (a dynamic emit, whose event name is unknowable, forcing
105/// a whole-file abstain). Event names allow kebab and namespaced forms
106/// (`update:modelValue`, `my-event`). The Rust `regex` crate has no
107/// backreferences, so the two quote styles are separate alternatives.
108static TEMPLATE_EMIT_CALL_RE: LazyLock<regex::Regex> =
109    LazyLock::new(|| crate::static_regex(r#"([\w$]+)\s*\(\s*(?:'([\w:-]*)'|"([\w:-]*)"|(\S))"#));
110
111/// Regex to extract `<style>` block content from Vue/Svelte SFCs.
112/// Mirrors `SCRIPT_BLOCK_RE`: handles `>` inside quoted attribute values and
113/// captures the body so `@import` / `@use` / `@forward` directives can be parsed.
114static STYLE_BLOCK_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
115    crate::static_regex(
116        r#"(?is)<style\b(?P<attrs>(?:[^>"']|"[^"]*"|'[^']*')*)>(?P<body>[\s\S]*?)</style>"#,
117    )
118});
119
120/// Static asset references in SFC markup: `<img src="./logo.png">`,
121/// `<source src="...">`, `<video poster="...">`, etc.
122///
123/// Scoped to genuine asset elements (`img` / `source` / `video` / `audio` /
124/// `track` / `embed`) so a custom component's `src` PROP (`<MyImage src="./x">`)
125/// is never misread as an asset edge. ONLY plain relative literals (`./` or
126/// `../`) are captured: dynamic bindings (`:src`, `v-bind:src`, `bind:src`,
127/// `src={...}`, `data-src`), alias-prefixed (`@/`), root-relative (`/foo`),
128/// remote, interpolated (`{{ }}` / `{ }`), and query/hash-suffixed values are
129/// all skipped (the value class excludes `{`, `?`, `#`, whitespace, and angle
130/// brackets, and the alternation anchors on a leading `./` or `../`). A
131/// captured ref becomes a `SideEffect` import; an existing asset resolves to
132/// `ExternalFile` (no finding) and a genuinely-missing one surfaces as
133/// `unresolved-import` on the trusted resolver path.
134static TEMPLATE_ASSET_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
135    crate::static_regex(
136        r#"(?si)<(?:img|source|video|audio|track|embed)\b(?:[^>"']|"[^"]*"|'[^']*')*?\s(?:src|poster)\s*=\s*(?:"((?:\./|\.\./)[^"<>{}?#\s]*)"|'((?:\./|\.\./)[^'<>{}?#\s]*)')"#,
137    )
138});
139
140/// Mask `<script>` / `<style>` blocks and HTML comments to equal-length spaces
141/// so a markup-region scan (asset refs) sees only the template, while byte
142/// offsets still map 1:1 into the original source for line/col reporting.
143fn mask_non_markup_regions(source: &str) -> String {
144    let mut masked = source.to_string();
145    for re in [&*SCRIPT_BLOCK_RE, &*STYLE_BLOCK_RE, &*HTML_COMMENT_RE] {
146        masked = re
147            .replace_all(&masked, |caps: &regex::Captures<'_>| {
148                " ".repeat(caps[0].len())
149            })
150            .into_owned();
151    }
152    masked
153}
154
155/// Collect static relative asset references from SFC markup as
156/// `(normalized_specifier, value_span)` pairs. See [`TEMPLATE_ASSET_RE`].
157fn collect_template_asset_refs(source: &str) -> Vec<(String, Span)> {
158    let masked = mask_non_markup_regions(source);
159    let mut refs = Vec::new();
160    for caps in TEMPLATE_ASSET_RE.captures_iter(&masked) {
161        let Some(value) = caps.get(1).or_else(|| caps.get(2)) else {
162            continue;
163        };
164        let raw = value.as_str();
165        if raw.is_empty() {
166            continue;
167        }
168        refs.push((
169            normalize_asset_url(raw),
170            Span::new(value.start() as u32, value.end() as u32),
171        ));
172    }
173    refs
174}
175
176/// An extracted `<script>` block from a Vue or Svelte SFC.
177pub struct SfcScript {
178    /// The script body text.
179    pub body: String,
180    /// Whether the script uses TypeScript (`lang="ts"` or `lang="tsx"`).
181    pub is_typescript: bool,
182    /// Whether the script uses JSX syntax (`lang="tsx"` or `lang="jsx"`).
183    pub is_jsx: bool,
184    /// Byte offset of the script body within the full SFC source.
185    pub byte_offset: usize,
186    /// External script source path from `src` attribute.
187    pub src: Option<String>,
188    /// Span of the `src` attribute value in the full SFC source.
189    pub src_span: Option<Span>,
190    /// Whether this script is a Vue `<script setup>` block.
191    pub is_setup: bool,
192    /// Whether this script is a Svelte module-context block.
193    pub is_context_module: bool,
194    /// Type-parameter list from a `generic="..."` (Vue) or `generics="..."`
195    /// (Svelte) attribute on the script tag. Holds the bare constraint, no
196    /// surrounding angle brackets, e.g. `T extends Test<boolean>`.
197    pub generic_attr: Option<String>,
198}
199
200/// Extract all `<script>` blocks from a Vue/Svelte SFC source string.
201pub fn extract_sfc_scripts(source: &str) -> Vec<SfcScript> {
202    let comment_ranges: Vec<(usize, usize)> = HTML_COMMENT_RE
203        .find_iter(source)
204        .map(|m| (m.start(), m.end()))
205        .collect();
206
207    SCRIPT_BLOCK_RE
208        .captures_iter(source)
209        .filter(|cap| {
210            let start = cap.get(0).map_or(0, |m| m.start());
211            !comment_ranges
212                .iter()
213                .any(|&(cs, ce)| start >= cs && start < ce)
214        })
215        .map(|cap| {
216            let attrs = cap.name("attrs").map_or("", |m| m.as_str());
217            let body_match = cap.name("body");
218            let byte_offset = body_match.map_or(0, |m| m.start());
219            let body = body_match.map_or("", |m| m.as_str()).to_string();
220            let lang = LANG_ATTR_RE
221                .captures(attrs)
222                .and_then(|c| c.get(1))
223                .map(|m| m.as_str());
224            let is_typescript = matches!(lang, Some("ts" | "tsx"));
225            let is_jsx = matches!(lang, Some("tsx" | "jsx"));
226            let src = SRC_ATTR_RE
227                .captures(attrs)
228                .and_then(|c| c.get(1))
229                .map(|m| m.as_str().to_string());
230            let attrs_start = cap.name("attrs").map_or(0, |m| m.start());
231            let src_span = SRC_ATTR_RE.captures(attrs).and_then(|c| c.get(1)).map(|m| {
232                Span::new(
233                    (attrs_start + m.start()) as u32,
234                    (attrs_start + m.end()) as u32,
235                )
236            });
237            let is_setup = SETUP_ATTR_RE.is_match(attrs);
238            // Svelte module context: Svelte 4 `context="module"` OR Svelte 5's
239            // bare `module` attribute. Both scope declarations to the module
240            // script (not the instance), so `is_template_visible_script` returns
241            // false and the instance/module split for runes harvest is correct.
242            let is_context_module =
243                CONTEXT_MODULE_ATTR_RE.is_match(attrs) || SVELTE_MODULE_ATTR_RE.is_match(attrs);
244            let generic_attr = VUE_GENERIC_ATTR_RE
245                .captures(attrs)
246                .or_else(|| SVELTE_GENERICS_ATTR_RE.captures(attrs))
247                .and_then(|cap| cap.get(1).or_else(|| cap.get(2)))
248                .map(|m| m.as_str().to_string())
249                .filter(|value| !value.trim().is_empty());
250            SfcScript {
251                body,
252                is_typescript,
253                is_jsx,
254                byte_offset,
255                src,
256                src_span,
257                is_setup,
258                is_context_module,
259                generic_attr,
260            }
261        })
262        .collect()
263}
264
265/// An extracted `<style>` block from a Vue or Svelte SFC.
266pub struct SfcStyle {
267    /// The style body text (CSS / SCSS / Sass / Less / Stylus / PostCSS source).
268    pub body: String,
269    /// The `lang` attribute value (`scss`, `sass`, `less`, `stylus`, `postcss`, ...).
270    /// `None` for plain `<style>` (CSS).
271    pub lang: Option<String>,
272    /// External style source path from the `src` attribute (`<style src="./theme.scss">`).
273    pub src: Option<String>,
274    /// Span of the `src` attribute value in the full SFC source.
275    pub src_span: Option<Span>,
276    /// Byte offset of the style body within the full SFC source.
277    pub byte_offset: usize,
278}
279
280/// A source region extracted from a larger file while preserving the byte
281/// offset of the region body in the original source.
282pub struct SourceRegion {
283    /// Region body text.
284    pub body: String,
285    /// Byte offset of `body` within the original source.
286    pub byte_offset: usize,
287}
288
289/// Extract template markup regions from a Vue/Svelte SFC.
290///
291/// The returned regions exclude `<script>` blocks, `<style>` blocks, and HTML
292/// comments, so callers can tokenize authored markup without reading code or
293/// comments as template text. Offsets always point into the original SFC source.
294#[must_use]
295pub fn extract_sfc_template_regions(source: &str) -> Vec<SourceRegion> {
296    let mut ranges: Vec<(usize, usize)> = SCRIPT_BLOCK_RE
297        .find_iter(source)
298        .chain(STYLE_BLOCK_RE.find_iter(source))
299        .chain(HTML_COMMENT_RE.find_iter(source))
300        .map(|m| (m.start(), m.end()))
301        .collect();
302    ranges.sort_unstable_by_key(|(start, _)| *start);
303    ranges_to_gaps(source, &ranges)
304}
305
306/// Extract all `<style>` blocks from a Vue/Svelte SFC source string.
307///
308/// Mirrors [`extract_sfc_scripts`]: filters blocks inside HTML comments and
309/// captures the `lang` and `src` attributes so the caller can route the body to
310/// the right preprocessor's import scanner (currently only CSS / SCSS / Sass) or
311/// seed the `src` reference as a side-effect import.
312pub fn extract_sfc_styles(source: &str) -> Vec<SfcStyle> {
313    let comment_ranges: Vec<(usize, usize)> = HTML_COMMENT_RE
314        .find_iter(source)
315        .map(|m| (m.start(), m.end()))
316        .collect();
317
318    STYLE_BLOCK_RE
319        .captures_iter(source)
320        .filter(|cap| {
321            let start = cap.get(0).map_or(0, |m| m.start());
322            !comment_ranges
323                .iter()
324                .any(|&(cs, ce)| start >= cs && start < ce)
325        })
326        .map(|cap| {
327            let attrs = cap.name("attrs").map_or("", |m| m.as_str());
328            let body = cap.name("body").map_or("", |m| m.as_str()).to_string();
329            let byte_offset = cap.name("body").map_or(0, |m| m.start());
330            let lang = LANG_ATTR_RE
331                .captures(attrs)
332                .and_then(|c| c.get(1))
333                .map(|m| m.as_str().to_string());
334            let src = SRC_ATTR_RE
335                .captures(attrs)
336                .and_then(|c| c.get(1))
337                .map(|m| m.as_str().to_string());
338            let attrs_start = cap.name("attrs").map_or(0, |m| m.start());
339            let src_span = SRC_ATTR_RE.captures(attrs).and_then(|c| c.get(1)).map(|m| {
340                Span::new(
341                    (attrs_start + m.start()) as u32,
342                    (attrs_start + m.end()) as u32,
343                )
344            });
345            SfcStyle {
346                body,
347                lang,
348                src,
349                src_span,
350                byte_offset,
351            }
352        })
353        .collect()
354}
355
356fn ranges_to_gaps(source: &str, ranges: &[(usize, usize)]) -> Vec<SourceRegion> {
357    let mut regions = Vec::new();
358    let mut cursor = 0;
359    for &(start, end) in ranges {
360        if start > cursor {
361            push_region(source, cursor, start, &mut regions);
362        }
363        cursor = cursor.max(end);
364    }
365    if cursor < source.len() {
366        push_region(source, cursor, source.len(), &mut regions);
367    }
368    regions
369}
370
371fn push_region(source: &str, start: usize, end: usize, regions: &mut Vec<SourceRegion>) {
372    let Some(body) = source.get(start..end) else {
373        return;
374    };
375    if body.trim().is_empty() {
376        return;
377    }
378    regions.push(SourceRegion {
379        body: body.to_string(),
380        byte_offset: start,
381    });
382}
383
384/// Check if a file path is a Vue or Svelte SFC (`.vue` or `.svelte`).
385#[must_use]
386pub fn is_sfc_file(path: &Path) -> bool {
387    path.extension()
388        .and_then(|e| e.to_str())
389        .is_some_and(|ext| ext == "vue" || ext == "svelte")
390}
391
392/// Parse an SFC file by extracting and combining all `<script>` and `<style>` blocks.
393pub(crate) fn parse_sfc_to_module(
394    file_id: FileId,
395    path: &Path,
396    source: &str,
397    content_hash: u64,
398    need_complexity: bool,
399) -> ModuleInfo {
400    let scripts = extract_sfc_scripts(source);
401    let styles = extract_sfc_styles(source);
402    let kind = sfc_kind(path);
403    let mut combined = empty_sfc_module(file_id, source, content_hash);
404    let mut template_visible_imports: FxHashSet<String> = FxHashSet::default();
405    let mut template_visible_bound_targets: FxHashMap<String, String> = FxHashMap::default();
406    let mut props_return_binding: Option<String> = None;
407    let mut emit_return_binding: Option<String> = None;
408
409    for script in &scripts {
410        merge_script_into_module(&mut SfcScriptMergeInput {
411            kind,
412            script,
413            combined: &mut combined,
414            template_visible_imports: &mut template_visible_imports,
415            template_visible_bound_targets: &mut template_visible_bound_targets,
416            props_return_binding: &mut props_return_binding,
417            emit_return_binding: &mut emit_return_binding,
418            need_complexity,
419        });
420    }
421
422    for style in &styles {
423        merge_style_into_module(style, &mut combined);
424    }
425
426    // Whole-object prop/attr spread in the template (`v-bind="$attrs"`,
427    // `v-bind="$props"`, `v-bind="props"`) can consume a prop indirectly, so the
428    // `unused-component-prop` detector must abstain on the whole file.
429    if kind == SfcKind::Vue
430        && !combined.component_props.is_empty()
431        && PROPS_ATTRS_SPREAD_RE.is_match(source)
432    {
433        combined.has_props_attrs_fallthrough = true;
434    }
435
436    apply_template_usage(TemplateUsageInput {
437        kind,
438        source,
439        template_visible_imports: &template_visible_imports,
440        template_visible_bound_targets: &template_visible_bound_targets,
441        props_return_binding: props_return_binding.as_deref(),
442        credit_load_data: kind == SfcKind::Svelte && is_sveltekit_route_data_component(path),
443        combined: &mut combined,
444    });
445
446    if need_complexity {
447        append_template_complexity(kind, source, &mut combined);
448    }
449
450    // Credit `<emit_binding>('event')` / `$emit('event')` calls in the template
451    // (`@click="emit('close')"`), which the script-only emit usage walk cannot
452    // see. A dynamic template emit (`$emit(someVar)`) abstains the whole file.
453    if kind == SfcKind::Vue && !combined.component_emits.is_empty() {
454        apply_template_emit_usage(source, emit_return_binding.as_deref(), &mut combined);
455    }
456
457    // Harvest Svelte template `on:<name>` listener bindings on component tags
458    // into the per-file listened set; the `unused-svelte-event` detector unions
459    // these project-wide to decide which dispatched events are dead.
460    if kind == SfcKind::Svelte {
461        combined.svelte_listened_events =
462            crate::sfc_template::collect_svelte_listened_events(source);
463    }
464
465    append_template_asset_imports(source, &mut combined);
466    dedup_import_binding_lists(&mut combined);
467
468    combined
469}
470
471/// Append the synthetic `<template>` complexity entry for the SFC. Counts
472/// template control flow (`v-if`/`v-for`, `{#if}`/`{#each}`) and
473/// bound-expression/interpolation complexity so a template-heavy SFC is not
474/// scored as artificially simple. The scanners mask `<script>`/`<style>`/comments,
475/// so script control flow is NOT double-counted (it is scored by
476/// `translate_script_complexity`). Mirrors Angular's synthetic entry; no new rule
477/// or threshold, the entry folds into the existing complexity aggregate.
478fn append_template_complexity(kind: SfcKind, source: &str, combined: &mut ModuleInfo) {
479    let template_complexity = match kind {
480        SfcKind::Vue => crate::template_complexity::compute_vue_template_complexity(source),
481        SfcKind::Svelte => crate::template_complexity::compute_svelte_template_complexity(source),
482    };
483    combined.complexity.extend(template_complexity);
484}
485
486/// Turn static relative asset references in markup (`<img src="./logo.png">`)
487/// into `SideEffect` imports so a genuinely-missing asset surfaces as
488/// `unresolved-import` (existing assets resolve to `ExternalFile`, no finding).
489fn append_template_asset_imports(source: &str, combined: &mut ModuleInfo) {
490    for (specifier, span) in collect_template_asset_refs(source) {
491        combined.imports.push(ImportInfo {
492            source: specifier,
493            imported_name: ImportedName::SideEffect,
494            local_name: String::new(),
495            is_type_only: false,
496            from_style: false,
497            span,
498            source_span: span,
499        });
500    }
501}
502
503/// Sort and dedup the per-script import-binding accumulator lists so the merged
504/// SFC module reports each binding once in a stable order.
505fn dedup_import_binding_lists(combined: &mut ModuleInfo) {
506    combined.unused_import_bindings.sort_unstable();
507    combined.unused_import_bindings.dedup();
508    combined.type_referenced_import_bindings.sort_unstable();
509    combined.type_referenced_import_bindings.dedup();
510    combined.value_referenced_import_bindings.sort_unstable();
511    combined.value_referenced_import_bindings.dedup();
512    combined.auto_import_candidates.sort_unstable();
513    combined.auto_import_candidates.dedup();
514}
515
516fn sfc_kind(path: &Path) -> SfcKind {
517    if path.extension().and_then(|ext| ext.to_str()) == Some("vue") {
518        SfcKind::Vue
519    } else {
520        SfcKind::Svelte
521    }
522}
523
524/// SvelteKit route components receive a `data` prop populated by the route's
525/// `load()` return object. This predicate gates the `data`-as-template-root
526/// credit (unused-load-data-key Primitive B) to exactly those files. It matches
527/// `+page.svelte` / `+layout.svelte` AND their layout-reset variants
528/// (`+page@.svelte`, `+page@named.svelte`, `+page@(group).svelte`, and the
529/// `+layout@...` forms), all of which still receive the `data` prop. `+error.svelte`
530/// is excluded (it receives `$page.error`, not the `load()` `data` prop), and a
531/// non-route file like `+pageHelper.svelte` is excluded by the grammar (the part
532/// after `+page` must be empty or start with `@`). The leading `+` is a
533/// SvelteKit-only filename convention, so no ordinary `.svelte` component matches.
534fn is_sveltekit_route_data_component(path: &Path) -> bool {
535    let Some(stem) = path
536        .file_name()
537        .and_then(|name| name.to_str())
538        .and_then(|name| name.strip_suffix(".svelte"))
539    else {
540        return false;
541    };
542    ["+page", "+layout"].iter().any(|prefix| {
543        stem.strip_prefix(prefix)
544            .is_some_and(|rest| rest.is_empty() || rest.starts_with('@'))
545    })
546}
547
548fn empty_sfc_module(file_id: FileId, source: &str, content_hash: u64) -> ModuleInfo {
549    let parsed = crate::suppress::parse_suppressions_from_source(source);
550
551    crate::module_info::non_js_module_info(
552        file_id,
553        content_hash,
554        source,
555        parsed,
556        Vec::new(),
557        Vec::new(),
558    )
559}
560
561struct SfcScriptMergeInput<'a> {
562    kind: SfcKind,
563    script: &'a SfcScript,
564    combined: &'a mut ModuleInfo,
565    template_visible_imports: &'a mut FxHashSet<String>,
566    template_visible_bound_targets: &'a mut FxHashMap<String, String>,
567    props_return_binding: &'a mut Option<String>,
568    emit_return_binding: &'a mut Option<String>,
569    need_complexity: bool,
570}
571
572fn merge_script_into_module(input: &mut SfcScriptMergeInput<'_>) {
573    if input.kind == SfcKind::Vue
574        && let Some(src) = &input.script.src
575    {
576        add_script_src_import(input.combined, src, input.script.src_span);
577    }
578
579    let allocator = Allocator::default();
580    let parser_return = Parser::new(
581        &allocator,
582        &input.script.body,
583        source_type_for_script(input.script),
584    )
585    .parse();
586    let mut extractor = ModuleInfoExtractor::new();
587    extractor.visit_program(&parser_return.program);
588    let extraction = ExtractionResult::contiguous(&input.script.body, input.script.byte_offset);
589    extractor.remap_spans_with(|span| extraction.remap_span(span));
590    extractor.resolve_typed_destructure_bindings();
591
592    merge_script_binding_usage(input, &allocator, &parser_return, &extractor.imports);
593    if input.need_complexity {
594        input
595            .combined
596            .complexity
597            .extend(translate_script_complexity(
598                input.script,
599                &parser_return.program,
600                &input.combined.line_offsets,
601            ));
602    }
603
604    // Vue prop/emit harvesting (`<script setup>` macros + Options API) for the
605    // `unused-component-prop` / `unused-component-emit` detectors. Extracted to a
606    // helper to keep this function under the unit-size lint.
607    if input.kind == SfcKind::Vue {
608        merge_vue_props_emits_into(input, &parser_return.program);
609    }
610
611    // Svelte 5 `$props()` rune harvesting for `unused-component-prop`. `$props`
612    // is an instance-only rune, so harvest ONLY the template-visible instance
613    // script, never the module script (`<script context="module">` /
614    // `<script module>`).
615    if input.kind == SfcKind::Svelte && is_template_visible_script(input.kind, input.script) {
616        merge_svelte_props_into(
617            input.combined,
618            &parser_return.program,
619            input.script.byte_offset,
620        );
621    }
622
623    if is_template_visible_script(input.kind, input.script) {
624        harvest_template_visible_bindings(input, &extractor);
625    }
626
627    // Dispatched events recorded by the visitor carry body-relative spans, like
628    // props/emits above. Remap the entries this script contributes onto the SFC
629    // source via the script byte offset so the finding line/col points at the
630    // real `dispatch(...)` call, not a body-relative position.
631    let dispatch_base = input.combined.svelte_dispatched_events.len();
632    extractor.merge_into(input.combined);
633    for event in &mut input.combined.svelte_dispatched_events[dispatch_base..] {
634        event.span_start += input.script.byte_offset as u32;
635    }
636}
637
638/// Compute and merge this script's import-binding usage (unused / type- and
639/// value-referenced) plus auto-import candidates into `combined`. A
640/// `generic="..."` attribute re-parses an augmented body so a type-only import
641/// consumed solely inside the constraint stays classified as type-referenced.
642fn merge_script_binding_usage(
643    input: &mut SfcScriptMergeInput<'_>,
644    allocator: &Allocator,
645    parser_return: &oxc_parser::ParserReturn<'_>,
646    imports: &[ImportInfo],
647) {
648    let augmented_body = build_generic_attr_probe_source(input.script);
649    let empty_template_used = FxHashSet::default();
650    let (binding_usage, auto_import_candidates) = if let Some(augmented) = augmented_body.as_deref()
651    {
652        let augmented_return =
653            Parser::new(allocator, augmented, source_type_for_script(input.script)).parse();
654        (
655            compute_import_binding_usage(&augmented_return.program, imports, &empty_template_used),
656            compute_auto_import_candidates(&parser_return.program),
657        )
658    } else {
659        let semantic_usage =
660            compute_semantic_usage(&parser_return.program, imports, &empty_template_used);
661        (
662            semantic_usage.import_binding_usage,
663            semantic_usage.auto_import_candidates,
664        )
665    };
666    input
667        .combined
668        .unused_import_bindings
669        .extend(binding_usage.unused.iter().cloned());
670    input
671        .combined
672        .type_referenced_import_bindings
673        .extend(binding_usage.type_referenced.iter().cloned());
674    input
675        .combined
676        .value_referenced_import_bindings
677        .extend(binding_usage.value_referenced.iter().cloned());
678    input
679        .combined
680        .auto_import_candidates
681        .extend(auto_import_candidates);
682}
683
684/// Carry an instance script's import locals and binding-target names into the
685/// template-visible sets (dropping empty locals and `this.`-prefixed targets) so
686/// the template scanner can credit them.
687fn harvest_template_visible_bindings(
688    input: &mut SfcScriptMergeInput<'_>,
689    extractor: &ModuleInfoExtractor,
690) {
691    input.template_visible_imports.extend(
692        extractor
693            .imports
694            .iter()
695            .filter(|import| !import.local_name.is_empty())
696            .map(|import| import.local_name.clone()),
697    );
698    input.template_visible_bound_targets.extend(
699        extractor
700            .binding_target_names()
701            .iter()
702            .filter(|(local, _)| !local.starts_with("this."))
703            .filter_map(|(local, target)| {
704                target
705                    .class_name()
706                    .map(|class_name| (local.clone(), class_name.to_string()))
707            }),
708    );
709}
710
711/// Harvest Svelte 5 `$props()` declared props from an instance `<script>`
712/// program into `combined.component_props` (reusing the Vue IR + abstain flags),
713/// remapping each prop's body-relative span onto the SFC source via `byte_offset`.
714fn merge_svelte_props_into(
715    combined: &mut ModuleInfo,
716    program: &oxc_ast::ast::Program<'_>,
717    byte_offset: usize,
718) {
719    let harvest = crate::sfc_props::harvest_svelte_props(program);
720    if harvest.has_unharvestable_props {
721        combined.has_unharvestable_props = true;
722    }
723    if harvest.has_props_attrs_fallthrough {
724        combined.has_props_attrs_fallthrough = true;
725    }
726    for mut prop in harvest.props {
727        prop.span_start += byte_offset as u32;
728        combined.component_props.push(prop);
729    }
730}
731
732/// Harvest Vue prop/emit declarations into `combined`, remapping body-relative
733/// spans onto the SFC source via the script byte offset. The `<script setup>`
734/// path harvests `defineProps` / `defineEmits` (and the `defineExpose` /
735/// `defineModel` abstain flags + return bindings); the non-setup path harvests
736/// the Options API `props:` / `emits:` (same IR, same abstain flags, same remap,
737/// only the harvest source differs).
738fn merge_vue_props_emits_into(
739    input: &mut SfcScriptMergeInput<'_>,
740    program: &oxc_ast::ast::Program<'_>,
741) {
742    let byte_offset = input.script.byte_offset as u32;
743    if input.script.is_setup {
744        apply_props_harvest(
745            input,
746            crate::sfc_props::harvest_define_props(program),
747            byte_offset,
748        );
749        apply_emits_harvest(
750            input,
751            crate::sfc_props::harvest_define_emits(program),
752            byte_offset,
753        );
754    } else {
755        apply_props_harvest(
756            input,
757            crate::sfc_props::harvest_options_api_props(program),
758            byte_offset,
759        );
760        apply_emits_harvest(
761            input,
762            crate::sfc_props::harvest_options_api_emits(program),
763            byte_offset,
764        );
765    }
766}
767
768/// Fold a prop harvest (setup `defineProps` or Options-API `props:`) into
769/// `combined`: copy the abstain flags and `defineProps` return binding, then push
770/// each prop with its span remapped onto the SFC source. The setup-only fields
771/// (`has_define_expose` / `has_define_model` / `props_return_binding`) default to
772/// `false`/`None` in the Options-API harvest, so the shared copy is inert there.
773fn apply_props_harvest(
774    input: &mut SfcScriptMergeInput<'_>,
775    harvest: crate::sfc_props::DefinePropsHarvest,
776    byte_offset: u32,
777) {
778    if harvest.has_unharvestable_props {
779        input.combined.has_unharvestable_props = true;
780    }
781    if harvest.has_props_attrs_fallthrough {
782        input.combined.has_props_attrs_fallthrough = true;
783    }
784    if harvest.has_define_expose {
785        input.combined.has_define_expose = true;
786    }
787    if harvest.has_define_model {
788        input.combined.has_define_model = true;
789    }
790    if let Some(binding) = harvest.props_return_binding {
791        *input.props_return_binding = Some(binding);
792    }
793    for mut prop in harvest.props {
794        prop.span_start += byte_offset;
795        input.combined.component_props.push(prop);
796    }
797}
798
799/// Fold an emit harvest (setup `defineEmits` or Options-API `emits:`) into
800/// `combined`: copy the abstain flags and emit return binding, then push each
801/// emit with its span remapped onto the SFC source. The setup-only fields
802/// (`has_emit_whole_object_use` / `emit_binding`) default to `false`/`None` in
803/// the Options-API harvest, so the shared copy is inert there.
804fn apply_emits_harvest(
805    input: &mut SfcScriptMergeInput<'_>,
806    harvest: crate::sfc_props::DefineEmitsHarvest,
807    byte_offset: u32,
808) {
809    if harvest.has_unharvestable_emits {
810        input.combined.has_unharvestable_emits = true;
811    }
812    if harvest.has_dynamic_emit {
813        input.combined.has_dynamic_emit = true;
814    }
815    if harvest.has_emit_whole_object_use {
816        input.combined.has_emit_whole_object_use = true;
817    }
818    if let Some(binding) = harvest.emit_binding {
819        *input.emit_return_binding = Some(binding);
820    }
821    for mut emit in harvest.emits {
822        emit.span_start += byte_offset;
823        input.combined.component_emits.push(emit);
824    }
825}
826
827fn translate_script_complexity(
828    script: &SfcScript,
829    program: &oxc_ast::ast::Program<'_>,
830    sfc_line_offsets: &[u32],
831) -> Vec<FunctionComplexity> {
832    let script_line_offsets = compute_line_offsets(&script.body);
833    let mut complexity =
834        crate::complexity::compute_complexity(program, &script.body, &script_line_offsets);
835    let (body_start_line, body_start_col) =
836        byte_offset_to_line_col(sfc_line_offsets, script.byte_offset as u32);
837
838    for function in &mut complexity {
839        function.line = body_start_line + function.line.saturating_sub(1);
840        if function.line == body_start_line {
841            function.col += body_start_col;
842        }
843    }
844
845    complexity
846}
847
848fn add_script_src_import(module: &mut ModuleInfo, source: &str, source_span: Option<Span>) {
849    let span = source_span.unwrap_or_default();
850    module.imports.push(ImportInfo {
851        source: normalize_asset_url(source),
852        imported_name: ImportedName::SideEffect,
853        local_name: String::new(),
854        is_type_only: false,
855        from_style: false,
856        span,
857        source_span: span,
858    });
859}
860
861/// `lang` attribute values whose body we know how to scan for `@import` /
862/// `@use` / `@forward` / `@plugin` directives. Plain `<style>` (no `lang`) is treated as
863/// CSS. `less`, `stylus`, and `postcss` bodies are NOT scanned because their
864/// import syntax differs (`@import (reference)` modifiers, etc.); their
865/// `<style src="...">` references are still seeded.
866fn style_lang_is_scss(lang: Option<&str>) -> bool {
867    matches!(lang, Some("scss" | "sass"))
868}
869
870fn style_lang_is_css_like(lang: Option<&str>) -> bool {
871    lang.is_none() || matches!(lang, Some("css"))
872}
873
874fn merge_style_into_module(style: &SfcStyle, combined: &mut ModuleInfo) {
875    if let Some(src) = &style.src {
876        let span = style.src_span.unwrap_or_default();
877        combined.imports.push(ImportInfo {
878            source: normalize_asset_url(src),
879            imported_name: ImportedName::SideEffect,
880            local_name: String::new(),
881            is_type_only: false,
882            from_style: true,
883            span,
884            source_span: span,
885        });
886    }
887
888    let lang = style.lang.as_deref();
889    let is_scss = style_lang_is_scss(lang);
890    let is_css_like = style_lang_is_css_like(lang);
891    if !is_scss && !is_css_like {
892        return;
893    }
894
895    for source in crate::css::extract_css_import_sources(&style.body, is_scss) {
896        let source_span = Span::new(
897            style.byte_offset as u32 + source.span.start,
898            style.byte_offset as u32 + source.span.end,
899        );
900        combined.imports.push(ImportInfo {
901            source: source.normalized,
902            imported_name: if source.is_plugin {
903                ImportedName::Default
904            } else {
905                ImportedName::SideEffect
906            },
907            local_name: String::new(),
908            is_type_only: false,
909            from_style: true,
910            span: source_span,
911            source_span,
912        });
913    }
914}
915
916fn source_type_for_script(script: &SfcScript) -> SourceType {
917    match (script.is_typescript, script.is_jsx) {
918        (true, true) => SourceType::tsx(),
919        (true, false) => SourceType::ts(),
920        (false, true) => SourceType::jsx(),
921        (false, false) => SourceType::mjs(),
922    }
923}
924
925/// Build an augmented script body that pins the `generic="..."` constraint as
926/// a synthetic local type alias. The alias is unexported and uses a sentinel
927/// name so it can't collide with user code. Returns `None` when there is no
928/// generic attribute to pin (the common case), so callers fall back to the
929/// raw body without paying for a second parse.
930fn build_generic_attr_probe_source(script: &SfcScript) -> Option<String> {
931    let constraint = script.generic_attr.as_deref()?.trim();
932    if constraint.is_empty() {
933        return None;
934    }
935    Some(format!(
936        "{}\n;type __FALLOW_GENERIC_ATTR_PROBE<{}> = unknown;\n",
937        script.body, constraint,
938    ))
939}
940
941struct TemplateUsageInput<'a> {
942    kind: SfcKind,
943    source: &'a str,
944    template_visible_imports: &'a FxHashSet<String>,
945    template_visible_bound_targets: &'a FxHashMap<String, String>,
946    props_return_binding: Option<&'a str>,
947    credit_load_data: bool,
948    combined: &'a mut ModuleInfo,
949}
950
951fn apply_template_usage(input: TemplateUsageInput<'_>) {
952    let TemplateUsageInput {
953        kind,
954        source,
955        template_visible_imports,
956        template_visible_bound_targets,
957        props_return_binding,
958        credit_load_data,
959        combined,
960    } = input;
961    let credited = build_template_credited_set(
962        template_visible_imports,
963        props_return_binding,
964        credit_load_data,
965        source,
966        combined,
967    );
968    let template_usage = compute_template_usage(
969        kind,
970        source,
971        &credited,
972        template_visible_bound_targets,
973        credit_load_data,
974    );
975    apply_prop_template_credit(&template_usage, props_return_binding, combined);
976    merge_template_usage_into_combined(template_usage, combined);
977}
978
979/// Build the set of template-credited names: the template-visible imports plus
980/// each harvested prop name / destructure local, Vue's implicit `$props`, the
981/// `defineProps` return binding, and (for SvelteKit route components) the `data`
982/// load prop. Crediting a prop name against an import is inert. Also sets
983/// `has_load_data_whole_use` when a route spreads / passes the whole `data` prop.
984fn build_template_credited_set(
985    template_visible_imports: &FxHashSet<String>,
986    props_return_binding: Option<&str>,
987    credit_load_data: bool,
988    source: &str,
989    combined: &mut ModuleInfo,
990) -> FxHashSet<String> {
991    let mut credited: FxHashSet<String> = template_visible_imports.clone();
992    // unused-load-data-key Primitive B: a SvelteKit route component receives a
993    // `data` prop populated by the route's `load()` return object. Credit `data`
994    // as a recognized root so its template member accesses (`data.<key>`) are
995    // emitted for the cross-file load-data-key join, gated to route components.
996    if credit_load_data {
997        credited.insert("data".to_string());
998        // FP-1: a route component spreading / passing the whole `data` prop in
999        // markup consumes arbitrary keys opaquely; force the detector to abstain.
1000        if SVELTE_TEMPLATE_DATA_WHOLE_USE_RE.is_match(source) {
1001            combined.has_load_data_whole_use = true;
1002        }
1003    }
1004    if !combined.component_props.is_empty() {
1005        for prop in &combined.component_props {
1006            // Credit both the declared name (Vue exposes props by name in the
1007            // template) and the destructure local (a renamed prop is used via it).
1008            credited.insert(prop.name.clone());
1009            credited.insert(prop.local.clone());
1010        }
1011        // Vue's implicit `$props` whole-props object is always available in a
1012        // template; credit `$props.<name>` member accesses too.
1013        credited.insert("$props".to_string());
1014        if let Some(binding) = props_return_binding {
1015            credited.insert(binding.to_string());
1016        }
1017    }
1018    credited
1019}
1020
1021/// Scan the template for usage of the credited names and bound targets. For a
1022/// SvelteKit route, `data` is dropped from the bound targets so its template
1023/// member accesses stay keyed on `data` (not remapped onto the generated
1024/// `PageData` / `LayoutData` type) for the cross-file load-data join.
1025fn compute_template_usage(
1026    kind: SfcKind,
1027    source: &str,
1028    credited: &FxHashSet<String>,
1029    template_visible_bound_targets: &FxHashMap<String, String>,
1030    credit_load_data: bool,
1031) -> crate::template_usage::TemplateUsage {
1032    if credit_load_data && template_visible_bound_targets.contains_key("data") {
1033        let mut filtered = template_visible_bound_targets.clone();
1034        filtered.remove("data");
1035        collect_template_usage_with_bound_targets(kind, source, credited, &filtered)
1036    } else {
1037        collect_template_usage_with_bound_targets(
1038            kind,
1039            source,
1040            credited,
1041            template_visible_bound_targets,
1042        )
1043    }
1044}
1045
1046/// Mark each harvested prop `used_in_template` when the template references it by
1047/// bare name (destructure form) or via a `<props>.<name>` / `$props.<name>`
1048/// member access. A bare reference to a custom `defineProps` return binding as a
1049/// whole object means abstain on the whole file (`has_props_attrs_fallthrough`).
1050fn apply_prop_template_credit(
1051    template_usage: &crate::template_usage::TemplateUsage,
1052    props_return_binding: Option<&str>,
1053    combined: &mut ModuleInfo,
1054) {
1055    if !combined.component_props.is_empty() {
1056        let member_used: FxHashSet<&str> = template_usage
1057            .member_accesses
1058            .iter()
1059            .filter(|access| {
1060                access.object == "$props"
1061                    || props_return_binding.is_some_and(|binding| access.object == binding)
1062            })
1063            .map(|access| access.member.as_str())
1064            .collect();
1065        for prop in &mut combined.component_props {
1066            if template_usage.used_bindings.contains(&prop.name)
1067                || template_usage.used_bindings.contains(&prop.local)
1068                || member_used.contains(prop.name.as_str())
1069            {
1070                prop.used_in_template = true;
1071            }
1072        }
1073    }
1074
1075    if let Some(binding) = props_return_binding
1076        && (template_usage.used_bindings.contains(binding)
1077            || template_usage
1078                .whole_object_uses
1079                .iter()
1080                .any(|used| used == binding))
1081    {
1082        combined.has_props_attrs_fallthrough = true;
1083    }
1084}
1085
1086/// Drain the scanned template usage into `combined`: retain unused-import
1087/// bindings the template did not consume, extend member accesses / whole-object
1088/// uses / security sinks, and fold unresolved tag names into auto-import
1089/// candidates (sorted + deduped).
1090fn merge_template_usage_into_combined(
1091    template_usage: crate::template_usage::TemplateUsage,
1092    combined: &mut ModuleInfo,
1093) {
1094    combined
1095        .unused_import_bindings
1096        .retain(|binding| !template_usage.used_bindings.contains(binding));
1097    combined
1098        .member_accesses
1099        .extend(template_usage.member_accesses);
1100    let mut whole_object_uses = std::mem::take(&mut combined.whole_object_uses).into_vec();
1101    whole_object_uses.extend(template_usage.whole_object_uses);
1102    combined.whole_object_uses = whole_object_uses.into_boxed_slice();
1103    combined
1104        .security_sinks
1105        .extend(template_usage.security_sinks);
1106    if !template_usage.unresolved_tag_names.is_empty() {
1107        let mut names: Vec<String> = template_usage.unresolved_tag_names.into_iter().collect();
1108        names.sort_unstable();
1109        combined.auto_import_candidates.extend(names);
1110        combined.auto_import_candidates.dedup();
1111    }
1112}
1113
1114/// Credit emit events fired from the `<template>` (`@click="emit('close')"`,
1115/// `@click="$emit('remove')"`, `:close="{ onClick: () => emit('close') }"`),
1116/// which the script-only emit usage walk in `harvest_define_emits` cannot see.
1117///
1118/// Scans the template-only region (scripts/styles/comments masked) for
1119/// [`TEMPLATE_EMIT_CALL_RE`]: a call whose callee is the harvested emit binding
1120/// (`emit` / `emits` / whatever it was bound to) or the implicit `$emit` (always
1121/// available in a Vue template regardless of `<script setup>` binding). A
1122/// string-literal first arg credits the matching `ComponentEmit` as used; a
1123/// non-literal first arg (a variable / template-literal) is a dynamic template
1124/// emit whose event is unknowable, so the whole file abstains (`has_dynamic_emit`)
1125/// to preserve the zero-FP doctrine.
1126///
1127/// Over-crediting is the safe direction (it only suppresses a finding), so a
1128/// liberal raw-source scan is intentional here. The scan is byte-safe: the regex
1129/// runs over the `&str` template and only reads captured-group text, never
1130/// slicing at arbitrary byte offsets.
1131fn apply_template_emit_usage(
1132    source: &str,
1133    emit_return_binding: Option<&str>,
1134    combined: &mut ModuleInfo,
1135) {
1136    let masked = mask_non_markup_regions(source);
1137    let mut used: FxHashSet<String> = FxHashSet::default();
1138    let mut dynamic = false;
1139
1140    for caps in TEMPLATE_EMIT_CALL_RE.captures_iter(&masked) {
1141        let Some(callee) = caps.get(1) else {
1142            continue;
1143        };
1144        let callee = callee.as_str();
1145        let is_emit_call =
1146            callee == "$emit" || emit_return_binding.is_some_and(|binding| callee == binding);
1147        if !is_emit_call {
1148            continue;
1149        }
1150        if let Some(event) = caps.get(2).or_else(|| caps.get(3)) {
1151            // String-literal first arg (single- or double-quoted): the event
1152            // name. Credit it as used.
1153            used.insert(event.as_str().to_string());
1154        } else if caps.get(4).is_some() {
1155            // Non-literal first arg (`$emit(someVar)`, `emit(\`x\`)`): the event
1156            // cannot be known. Abstain on the whole file.
1157            dynamic = true;
1158        }
1159    }
1160
1161    if dynamic {
1162        combined.has_dynamic_emit = true;
1163    }
1164    if !used.is_empty() {
1165        for emit in &mut combined.component_emits {
1166            if used.contains(&emit.name) {
1167                emit.used = true;
1168            }
1169        }
1170    }
1171}
1172
1173fn is_template_visible_script(kind: SfcKind, script: &SfcScript) -> bool {
1174    match kind {
1175        SfcKind::Vue => script.is_setup,
1176        SfcKind::Svelte => !script.is_context_module,
1177    }
1178}
1179
1180#[cfg(all(test, not(miri)))]
1181mod tests {
1182    use super::*;
1183
1184    #[test]
1185    fn is_sfc_file_vue() {
1186        assert!(is_sfc_file(Path::new("App.vue")));
1187    }
1188
1189    #[test]
1190    fn is_sfc_file_svelte() {
1191        assert!(is_sfc_file(Path::new("Counter.svelte")));
1192    }
1193
1194    #[test]
1195    fn is_sfc_file_rejects_ts() {
1196        assert!(!is_sfc_file(Path::new("utils.ts")));
1197    }
1198
1199    #[test]
1200    fn is_sfc_file_rejects_jsx() {
1201        assert!(!is_sfc_file(Path::new("App.jsx")));
1202    }
1203
1204    #[test]
1205    fn is_sfc_file_rejects_astro() {
1206        assert!(!is_sfc_file(Path::new("Layout.astro")));
1207    }
1208
1209    #[test]
1210    fn single_plain_script() {
1211        let scripts = extract_sfc_scripts("<script>const x = 1;</script>");
1212        assert_eq!(scripts.len(), 1);
1213        assert_eq!(scripts[0].body, "const x = 1;");
1214        assert!(!scripts[0].is_typescript);
1215        assert!(!scripts[0].is_jsx);
1216        assert!(scripts[0].src.is_none());
1217    }
1218
1219    #[test]
1220    fn single_ts_script() {
1221        let scripts = extract_sfc_scripts(r#"<script lang="ts">const x: number = 1;</script>"#);
1222        assert_eq!(scripts.len(), 1);
1223        assert!(scripts[0].is_typescript);
1224        assert!(!scripts[0].is_jsx);
1225    }
1226
1227    #[test]
1228    fn single_tsx_script() {
1229        let scripts = extract_sfc_scripts(r#"<script lang="tsx">const el = <div />;</script>"#);
1230        assert_eq!(scripts.len(), 1);
1231        assert!(scripts[0].is_typescript);
1232        assert!(scripts[0].is_jsx);
1233    }
1234
1235    #[test]
1236    fn single_jsx_script() {
1237        let scripts = extract_sfc_scripts(r#"<script lang="jsx">const el = <div />;</script>"#);
1238        assert_eq!(scripts.len(), 1);
1239        assert!(!scripts[0].is_typescript);
1240        assert!(scripts[0].is_jsx);
1241    }
1242
1243    #[test]
1244    fn two_script_blocks() {
1245        let source = r#"
1246<script lang="ts">
1247export default {};
1248</script>
1249<script setup lang="ts">
1250const count = 0;
1251</script>
1252"#;
1253        let scripts = extract_sfc_scripts(source);
1254        assert_eq!(scripts.len(), 2);
1255        assert!(scripts[0].body.contains("export default"));
1256        assert!(scripts[1].body.contains("count"));
1257    }
1258
1259    #[test]
1260    fn script_setup_extracted() {
1261        let scripts =
1262            extract_sfc_scripts(r#"<script setup lang="ts">import { ref } from 'vue';</script>"#);
1263        assert_eq!(scripts.len(), 1);
1264        assert!(scripts[0].body.contains("import"));
1265        assert!(scripts[0].is_typescript);
1266    }
1267
1268    #[test]
1269    fn script_src_detected() {
1270        let scripts = extract_sfc_scripts(r#"<script src="./component.ts" lang="ts"></script>"#);
1271        assert_eq!(scripts.len(), 1);
1272        assert_eq!(scripts[0].src.as_deref(), Some("./component.ts"));
1273    }
1274
1275    // -- Svelte module-context recognition (W1.1 piece 1) ----------------------
1276
1277    #[test]
1278    fn svelte4_context_module_is_module_context() {
1279        let scripts =
1280            extract_sfc_scripts(r#"<script context="module">export const x = 1;</script>"#);
1281        assert_eq!(scripts.len(), 1);
1282        assert!(scripts[0].is_context_module);
1283    }
1284
1285    #[test]
1286    fn svelte5_bare_module_attr_is_module_context() {
1287        let scripts = extract_sfc_scripts(r"<script module>export const x = 1;</script>");
1288        assert_eq!(scripts.len(), 1);
1289        assert!(scripts[0].is_context_module);
1290    }
1291
1292    #[test]
1293    fn svelte5_module_with_lang_is_module_context() {
1294        let scripts =
1295            extract_sfc_scripts(r#"<script module lang="ts">export const x = 1;</script>"#);
1296        assert_eq!(scripts.len(), 1);
1297        assert!(scripts[0].is_context_module);
1298        assert!(scripts[0].is_typescript);
1299    }
1300
1301    #[test]
1302    fn plain_script_is_not_module_context() {
1303        let scripts = extract_sfc_scripts(r"<script>const x = 1;</script>");
1304        assert_eq!(scripts.len(), 1);
1305        assert!(!scripts[0].is_context_module);
1306    }
1307
1308    #[test]
1309    fn lang_ts_script_is_not_module_context() {
1310        let scripts = extract_sfc_scripts(r#"<script lang="ts">const x = 1;</script>"#);
1311        assert_eq!(scripts.len(), 1);
1312        assert!(!scripts[0].is_context_module);
1313    }
1314
1315    #[test]
1316    fn data_module_attr_is_not_module_context() {
1317        // The `(?:^|\s)module(?:\s|$|=)` anchor must not match `data-module`.
1318        let scripts =
1319            extract_sfc_scripts(r#"<script data-module="x" lang="ts">const x = 1;</script>"#);
1320        assert_eq!(scripts.len(), 1);
1321        assert!(!scripts[0].is_context_module);
1322    }
1323
1324    #[test]
1325    fn bare_module_script_is_not_template_visible() {
1326        // AC-2: a bare `<script module>` is scoped as module context, so its
1327        // imports are NOT credited as template-visible (matching `context="module"`).
1328        let module_script = SfcScript {
1329            body: String::new(),
1330            is_typescript: false,
1331            is_jsx: false,
1332            byte_offset: 0,
1333            src: None,
1334            src_span: None,
1335            is_setup: false,
1336            is_context_module: true,
1337            generic_attr: None,
1338        };
1339        assert!(!is_template_visible_script(SfcKind::Svelte, &module_script));
1340        let instance_script = SfcScript {
1341            is_context_module: false,
1342            ..module_script
1343        };
1344        assert!(is_template_visible_script(
1345            SfcKind::Svelte,
1346            &instance_script
1347        ));
1348    }
1349
1350    #[test]
1351    fn data_src_not_treated_as_src() {
1352        let scripts =
1353            extract_sfc_scripts(r#"<script lang="ts" data-src="./nope.ts">const x = 1;</script>"#);
1354        assert_eq!(scripts.len(), 1);
1355        assert!(scripts[0].src.is_none());
1356    }
1357
1358    #[test]
1359    fn script_inside_html_comment_filtered() {
1360        let source = r#"
1361<!-- <script lang="ts">import { bad } from 'bad';</script> -->
1362<script lang="ts">import { good } from 'good';</script>
1363"#;
1364        let scripts = extract_sfc_scripts(source);
1365        assert_eq!(scripts.len(), 1);
1366        assert!(scripts[0].body.contains("good"));
1367    }
1368
1369    #[test]
1370    fn spanning_comment_filters_script() {
1371        let source = r#"
1372<!-- disabled:
1373<script lang="ts">import { bad } from 'bad';</script>
1374-->
1375<script lang="ts">const ok = true;</script>
1376"#;
1377        let scripts = extract_sfc_scripts(source);
1378        assert_eq!(scripts.len(), 1);
1379        assert!(scripts[0].body.contains("ok"));
1380    }
1381
1382    #[test]
1383    fn string_containing_comment_markers_not_corrupted() {
1384        let source = r#"
1385<script setup lang="ts">
1386const marker = "<!-- not a comment -->";
1387import { ref } from 'vue';
1388</script>
1389"#;
1390        let scripts = extract_sfc_scripts(source);
1391        assert_eq!(scripts.len(), 1);
1392        assert!(scripts[0].body.contains("import"));
1393    }
1394
1395    #[test]
1396    fn generic_attr_with_angle_bracket() {
1397        let source =
1398            r#"<script setup lang="ts" generic="T extends Foo<Bar>">const x = 1;</script>"#;
1399        let scripts = extract_sfc_scripts(source);
1400        assert_eq!(scripts.len(), 1);
1401        assert_eq!(scripts[0].body, "const x = 1;");
1402    }
1403
1404    #[test]
1405    fn nested_generic_attr() {
1406        let source = r#"<script setup lang="ts" generic="T extends Map<string, Set<number>>">const x = 1;</script>"#;
1407        let scripts = extract_sfc_scripts(source);
1408        assert_eq!(scripts.len(), 1);
1409        assert_eq!(scripts[0].body, "const x = 1;");
1410    }
1411
1412    #[test]
1413    fn lang_single_quoted() {
1414        let scripts = extract_sfc_scripts("<script lang='ts'>const x = 1;</script>");
1415        assert_eq!(scripts.len(), 1);
1416        assert!(scripts[0].is_typescript);
1417    }
1418
1419    #[test]
1420    fn uppercase_script_tag() {
1421        let scripts = extract_sfc_scripts(r#"<SCRIPT lang="ts">const x = 1;</SCRIPT>"#);
1422        assert_eq!(scripts.len(), 1);
1423        assert!(scripts[0].is_typescript);
1424    }
1425
1426    #[test]
1427    fn no_script_block() {
1428        let scripts = extract_sfc_scripts("<template><div>Hello</div></template>");
1429        assert!(scripts.is_empty());
1430    }
1431
1432    #[test]
1433    fn empty_script_body() {
1434        let scripts = extract_sfc_scripts(r#"<script lang="ts"></script>"#);
1435        assert_eq!(scripts.len(), 1);
1436        assert!(scripts[0].body.is_empty());
1437    }
1438
1439    #[test]
1440    fn whitespace_only_script() {
1441        let scripts = extract_sfc_scripts("<script lang=\"ts\">\n  \n</script>");
1442        assert_eq!(scripts.len(), 1);
1443        assert!(scripts[0].body.trim().is_empty());
1444    }
1445
1446    #[test]
1447    fn byte_offset_is_set() {
1448        let source = r#"<template><div/></template><script lang="ts">code</script>"#;
1449        let scripts = extract_sfc_scripts(source);
1450        assert_eq!(scripts.len(), 1);
1451        let offset = scripts[0].byte_offset;
1452        assert_eq!(&source[offset..offset + 4], "code");
1453    }
1454
1455    #[test]
1456    fn script_with_extra_attributes() {
1457        let scripts = extract_sfc_scripts(
1458            r#"<script lang="ts" id="app" type="module" data-custom="val">const x = 1;</script>"#,
1459        );
1460        assert_eq!(scripts.len(), 1);
1461        assert!(scripts[0].is_typescript);
1462        assert!(scripts[0].src.is_none());
1463    }
1464
1465    #[test]
1466    fn multiple_script_blocks_exports_combined() {
1467        let source = r#"
1468<script lang="ts">
1469export const version = '1.0';
1470</script>
1471<script setup lang="ts">
1472import { ref } from 'vue';
1473const count = ref(0);
1474</script>
1475"#;
1476        let info = parse_sfc_to_module(FileId(0), Path::new("Dual.vue"), source, 0, false);
1477        assert!(
1478            info.exports
1479                .iter()
1480                .any(|e| matches!(&e.name, crate::ExportName::Named(n) if n == "version")),
1481            "export from <script> block should be extracted"
1482        );
1483        assert!(
1484            info.imports.iter().any(|i| i.source == "vue"),
1485            "import from <script setup> block should be extracted"
1486        );
1487    }
1488
1489    #[test]
1490    fn lang_tsx_detected_as_typescript_jsx() {
1491        let scripts =
1492            extract_sfc_scripts(r#"<script lang="tsx">const el = <div>{x}</div>;</script>"#);
1493        assert_eq!(scripts.len(), 1);
1494        assert!(scripts[0].is_typescript, "lang=tsx should be typescript");
1495        assert!(scripts[0].is_jsx, "lang=tsx should be jsx");
1496    }
1497
1498    #[test]
1499    fn multiline_html_comment_filters_all_script_blocks_inside() {
1500        let source = r#"
1501<!--
1502  This whole section is disabled:
1503  <script lang="ts">import { bad1 } from 'bad1';</script>
1504  <script lang="ts">import { bad2 } from 'bad2';</script>
1505-->
1506<script lang="ts">import { good } from 'good';</script>
1507"#;
1508        let scripts = extract_sfc_scripts(source);
1509        assert_eq!(scripts.len(), 1);
1510        assert!(scripts[0].body.contains("good"));
1511    }
1512
1513    #[test]
1514    fn script_src_generates_side_effect_import() {
1515        let info = parse_sfc_to_module(
1516            FileId(0),
1517            Path::new("External.vue"),
1518            r#"<script src="./external-logic.ts" lang="ts"></script>"#,
1519            0,
1520            false,
1521        );
1522        assert!(
1523            info.imports
1524                .iter()
1525                .any(|i| i.source == "./external-logic.ts"
1526                    && matches!(i.imported_name, ImportedName::SideEffect)),
1527            "script src should generate a side-effect import"
1528        );
1529    }
1530
1531    #[test]
1532    fn parse_sfc_no_script_returns_empty_module() {
1533        let info = parse_sfc_to_module(
1534            FileId(0),
1535            Path::new("Empty.vue"),
1536            "<template><div>Hello</div></template>",
1537            42,
1538            false,
1539        );
1540        assert!(info.imports.is_empty());
1541        assert!(info.exports.is_empty());
1542        assert_eq!(info.content_hash, 42);
1543        assert_eq!(info.file_id, FileId(0));
1544    }
1545
1546    #[test]
1547    fn parse_sfc_has_line_offsets() {
1548        let info = parse_sfc_to_module(
1549            FileId(0),
1550            Path::new("LineOffsets.vue"),
1551            r#"<script lang="ts">const x = 1;</script>"#,
1552            0,
1553            false,
1554        );
1555        assert!(!info.line_offsets.is_empty());
1556    }
1557
1558    #[test]
1559    fn parse_sfc_has_suppressions() {
1560        let info = parse_sfc_to_module(
1561            FileId(0),
1562            Path::new("Suppressions.vue"),
1563            r#"<script lang="ts">
1564// fallow-ignore-file
1565export const foo = 1;
1566</script>"#,
1567            0,
1568            false,
1569        );
1570        assert!(!info.suppressions.is_empty());
1571    }
1572
1573    #[test]
1574    fn source_type_jsx_detection() {
1575        let scripts = extract_sfc_scripts(r#"<script lang="jsx">const el = <div />;</script>"#);
1576        assert_eq!(scripts.len(), 1);
1577        assert!(!scripts[0].is_typescript);
1578        assert!(scripts[0].is_jsx);
1579    }
1580
1581    #[test]
1582    fn source_type_plain_js_detection() {
1583        let scripts = extract_sfc_scripts("<script>const x = 1;</script>");
1584        assert_eq!(scripts.len(), 1);
1585        assert!(!scripts[0].is_typescript);
1586        assert!(!scripts[0].is_jsx);
1587    }
1588
1589    #[test]
1590    fn is_sfc_file_rejects_no_extension() {
1591        assert!(!is_sfc_file(Path::new("Makefile")));
1592    }
1593
1594    #[test]
1595    fn is_sfc_file_rejects_mdx() {
1596        assert!(!is_sfc_file(Path::new("post.mdx")));
1597    }
1598
1599    #[test]
1600    fn is_sfc_file_rejects_css() {
1601        assert!(!is_sfc_file(Path::new("styles.css")));
1602    }
1603
1604    #[test]
1605    fn multiple_script_blocks_both_have_offsets() {
1606        let source = r#"<script lang="ts">const a = 1;</script>
1607<script setup lang="ts">const b = 2;</script>"#;
1608        let scripts = extract_sfc_scripts(source);
1609        assert_eq!(scripts.len(), 2);
1610        let offset0 = scripts[0].byte_offset;
1611        let offset1 = scripts[1].byte_offset;
1612        assert_eq!(
1613            &source[offset0..offset0 + "const a = 1;".len()],
1614            "const a = 1;"
1615        );
1616        assert_eq!(
1617            &source[offset1..offset1 + "const b = 2;".len()],
1618            "const b = 2;"
1619        );
1620    }
1621
1622    #[test]
1623    fn script_with_src_and_lang() {
1624        let scripts = extract_sfc_scripts(r#"<script src="./logic.ts" lang="tsx"></script>"#);
1625        assert_eq!(scripts.len(), 1);
1626        assert_eq!(scripts[0].src.as_deref(), Some("./logic.ts"));
1627        assert!(scripts[0].is_typescript);
1628        assert!(scripts[0].is_jsx);
1629    }
1630
1631    #[test]
1632    fn extract_style_block_lang_scss() {
1633        let source = r#"<template/><style lang="scss">@import 'Foo';</style>"#;
1634        let styles = extract_sfc_styles(source);
1635        assert_eq!(styles.len(), 1);
1636        assert_eq!(styles[0].lang.as_deref(), Some("scss"));
1637        assert!(styles[0].body.contains("@import"));
1638        assert!(styles[0].src.is_none());
1639    }
1640
1641    #[test]
1642    fn extract_style_block_with_src() {
1643        let source = r#"<style src="./theme.scss" lang="scss"></style>"#;
1644        let styles = extract_sfc_styles(source);
1645        assert_eq!(styles.len(), 1);
1646        assert_eq!(styles[0].src.as_deref(), Some("./theme.scss"));
1647        assert_eq!(styles[0].lang.as_deref(), Some("scss"));
1648    }
1649
1650    #[test]
1651    fn extract_style_block_plain_no_lang() {
1652        let source = r"<style>.foo { color: red; }</style>";
1653        let styles = extract_sfc_styles(source);
1654        assert_eq!(styles.len(), 1);
1655        assert!(styles[0].lang.is_none());
1656    }
1657
1658    #[test]
1659    fn extract_multiple_style_blocks() {
1660        let source = r#"<style lang="scss">@import 'a';</style>
1661<style scoped lang="scss">@import 'b';</style>"#;
1662        let styles = extract_sfc_styles(source);
1663        assert_eq!(styles.len(), 2);
1664    }
1665
1666    #[test]
1667    fn style_block_inside_html_comment_filtered() {
1668        let source = r#"<!-- <style lang="scss">@import 'bad';</style> -->
1669<style lang="scss">@import 'good';</style>"#;
1670        let styles = extract_sfc_styles(source);
1671        assert_eq!(styles.len(), 1);
1672        assert!(styles[0].body.contains("good"));
1673    }
1674
1675    #[test]
1676    fn parse_sfc_extracts_style_imports_with_from_style_flag() {
1677        let info = parse_sfc_to_module(
1678            FileId(0),
1679            Path::new("Foo.vue"),
1680            r#"<template/><style lang="scss">@import 'Foo';</style>"#,
1681            0,
1682            false,
1683        );
1684        let style_import = info
1685            .imports
1686            .iter()
1687            .find(|i| i.source == "./Foo")
1688            .expect("scss @import 'Foo' should be normalized to ./Foo");
1689        assert!(
1690            style_import.from_style,
1691            "imports from <style> blocks must carry from_style=true so the resolver \
1692             enables SCSS partial fallback for the SFC importer"
1693        );
1694        assert!(matches!(
1695            style_import.imported_name,
1696            ImportedName::SideEffect
1697        ));
1698    }
1699
1700    #[test]
1701    fn parse_sfc_extracts_style_plugin_as_default_import() {
1702        let info = parse_sfc_to_module(
1703            FileId(0),
1704            Path::new("Foo.vue"),
1705            r#"<template/><style>@plugin "./tailwind-plugin.js";</style>"#,
1706            0,
1707            false,
1708        );
1709        let plugin_import = info
1710            .imports
1711            .iter()
1712            .find(|i| i.source == "./tailwind-plugin.js")
1713            .expect("style @plugin should create an import");
1714        assert!(plugin_import.from_style);
1715        assert!(matches!(plugin_import.imported_name, ImportedName::Default));
1716    }
1717
1718    #[test]
1719    fn parse_sfc_extracts_style_src_with_from_style_flag() {
1720        let info = parse_sfc_to_module(
1721            FileId(0),
1722            Path::new("Bar.vue"),
1723            r#"<style src="./Bar.scss" lang="scss"></style>"#,
1724            0,
1725            false,
1726        );
1727        let style_src = info
1728            .imports
1729            .iter()
1730            .find(|i| i.source == "./Bar.scss")
1731            .expect("<style src=\"./Bar.scss\"> should produce a side-effect import");
1732        assert!(style_src.from_style);
1733    }
1734
1735    #[test]
1736    fn parse_sfc_skips_unsupported_style_lang_body_but_keeps_src() {
1737        let info = parse_sfc_to_module(
1738            FileId(0),
1739            Path::new("Baz.vue"),
1740            r#"<style lang="postcss" src="./Baz.pcss">@custom-rule "skipped";</style>"#,
1741            0,
1742            false,
1743        );
1744        assert!(
1745            info.imports.iter().any(|i| i.source == "./Baz.pcss"),
1746            "src reference should still be seeded for unsupported lang"
1747        );
1748        assert!(
1749            !info.imports.iter().any(|i| i.source.contains("skipped")),
1750            "postcss body should not be scanned for @import directives"
1751        );
1752    }
1753
1754    fn asset_refs(source: &str) -> Vec<String> {
1755        super::collect_template_asset_refs(source)
1756            .into_iter()
1757            .map(|(s, _)| s)
1758            .collect()
1759    }
1760
1761    #[test]
1762    fn captures_static_relative_template_asset_refs() {
1763        assert_eq!(
1764            asset_refs(r#"<template><img src="./logo.png" /></template>"#),
1765            vec!["./logo.png".to_string()]
1766        );
1767        assert_eq!(
1768            asset_refs(r#"<source src="../media/clip.mp4">"#),
1769            vec!["../media/clip.mp4".to_string()]
1770        );
1771        assert_eq!(
1772            asset_refs(r#"<video poster="./thumb.jpg"></video>"#),
1773            vec!["./thumb.jpg".to_string()]
1774        );
1775    }
1776
1777    #[test]
1778    fn skips_dynamic_alias_root_remote_and_query_asset_refs() {
1779        // Dynamic bindings (Vue `:src`, `v-bind:src`, Svelte `bind:src` / `src={}`).
1780        assert!(asset_refs(r#"<img :src="logo" />"#).is_empty());
1781        assert!(asset_refs(r#"<img v-bind:src="logo" />"#).is_empty());
1782        assert!(asset_refs(r#"<img bind:src="logo" />"#).is_empty());
1783        assert!(asset_refs(r"<img src={logo} />").is_empty());
1784        assert!(asset_refs(r#"<img data-src="./x.png" />"#).is_empty());
1785        // Alias-prefixed, root-relative, remote, bare: not plain relative literals.
1786        assert!(asset_refs(r#"<img src="@/assets/x.png" />"#).is_empty());
1787        assert!(asset_refs(r#"<img src="/logo.png" />"#).is_empty());
1788        assert!(asset_refs(r#"<img src="https://cdn/x.png" />"#).is_empty());
1789        // Query / hash suffix abstains (the resolver cannot verify them).
1790        assert!(asset_refs(r#"<img src="./x.png?inline" />"#).is_empty());
1791        // Interpolated value abstains.
1792        assert!(asset_refs(r#"<img src="{{ logo }}" />"#).is_empty());
1793    }
1794
1795    #[test]
1796    fn skips_custom_component_src_prop() {
1797        // A custom component's `src` PROP must never be read as an asset edge.
1798        assert!(asset_refs(r#"<MyImage src="./x.png" />"#).is_empty());
1799        assert!(asset_refs(r#"<AppIcon src="../icons/y.svg" />"#).is_empty());
1800    }
1801
1802    #[test]
1803    fn skips_asset_refs_inside_script_style_and_comments() {
1804        // Masked regions must not contribute asset refs.
1805        assert!(asset_refs(r#"<script>const x = "<img src='./a.png'>"</script>"#).is_empty());
1806        assert!(asset_refs(r#"<style>/* <img src="./b.png"> */ .x{}</style>"#).is_empty());
1807        assert!(asset_refs(r#"<!-- <img src="./c.png" /> -->"#).is_empty());
1808    }
1809
1810    #[test]
1811    fn parse_sfc_emits_template_asset_as_side_effect_import() {
1812        let info = parse_sfc_to_module(
1813            FileId(0),
1814            Path::new("Hero.vue"),
1815            r#"<template><img src="./hero.png" /></template><script>let x=1</script>"#,
1816            0,
1817            false,
1818        );
1819        assert!(
1820            info.imports.iter().any(|i| i.source == "./hero.png"
1821                && matches!(i.imported_name, ImportedName::SideEffect)
1822                && !i.from_style),
1823            "template <img src> should seed a SideEffect import: {:?}",
1824            info.imports
1825        );
1826    }
1827
1828    // -- Svelte 5 `$props()` rune harvest (W1.1 piece 2) -----------------------
1829
1830    fn svelte_props(source: &str) -> Vec<crate::ModuleInfo> {
1831        vec![parse_sfc_to_module(
1832            FileId(0),
1833            Path::new("Component.svelte"),
1834            source,
1835            0,
1836            false,
1837        )]
1838    }
1839
1840    fn prop_names(info: &crate::ModuleInfo) -> Vec<String> {
1841        let mut names: Vec<String> = info
1842            .component_props
1843            .iter()
1844            .map(|p| p.name.clone())
1845            .collect();
1846        names.sort();
1847        names
1848    }
1849
1850    #[test]
1851    fn svelte_shorthand_props_harvested() {
1852        // AC-3: `let { a, b } = $props()` harvests `a`, `b` with `local == name`.
1853        let info = &svelte_props(r"<script>let { a, b } = $props();</script>")[0];
1854        assert_eq!(prop_names(info), vec!["a", "b"]);
1855        for prop in &info.component_props {
1856            assert_eq!(prop.local, prop.name);
1857        }
1858    }
1859
1860    #[test]
1861    fn svelte_renamed_prop_tracks_local_and_script_use() {
1862        // AC-4: `let { a: alias } = $props()` harvests `a` with `local == "alias"`,
1863        // and a reference to `alias` sets `used_in_script` for prop `a`.
1864        let info =
1865            &svelte_props(r"<script>let { a: alias } = $props(); console.log(alias);</script>")[0];
1866        assert_eq!(prop_names(info), vec!["a"]);
1867        let prop = &info.component_props[0];
1868        assert_eq!(prop.local, "alias");
1869        assert!(
1870            prop.used_in_script,
1871            "alias is referenced, so a is used in script"
1872        );
1873    }
1874
1875    #[test]
1876    fn svelte_unreferenced_prop_is_unused_in_script() {
1877        let info = &svelte_props(r"<script>let { a } = $props();</script>")[0];
1878        assert_eq!(prop_names(info), vec!["a"]);
1879        assert!(!info.component_props[0].used_in_script);
1880    }
1881
1882    #[test]
1883    fn svelte_default_prop_peeled() {
1884        // AC-5: `let { a = 1 } = $props()` harvests `a` (default peeled).
1885        let info = &svelte_props(r"<script>let { a = 1 } = $props();</script>")[0];
1886        assert_eq!(prop_names(info), vec!["a"]);
1887    }
1888
1889    #[test]
1890    fn svelte_bindable_default_peeled() {
1891        // The bindable form `let { a = $bindable() } = $props()`: `a` is still a
1892        // declared prop (the default value is irrelevant to the local name).
1893        let info = &svelte_props(r"<script>let { a = $bindable() } = $props();</script>")[0];
1894        assert_eq!(prop_names(info), vec!["a"]);
1895    }
1896
1897    #[test]
1898    fn svelte_rest_element_sets_fallthrough_abstain() {
1899        // AC-6: `let { a, ...rest } = $props()` sets has_props_attrs_fallthrough.
1900        let info = &svelte_props(r"<script>let { a, ...rest } = $props();</script>")[0];
1901        assert!(info.has_props_attrs_fallthrough);
1902    }
1903
1904    #[test]
1905    fn svelte_bare_identifier_binding_sets_unharvestable_abstain() {
1906        // AC-7: `let p = $props()` (no destructure) sets has_unharvestable_props.
1907        let info = &svelte_props(r"<script>let p = $props(); console.log(p.x);</script>")[0];
1908        assert!(info.has_unharvestable_props);
1909        assert!(info.component_props.is_empty());
1910    }
1911
1912    #[test]
1913    fn svelte_nested_destructure_sets_unharvestable_abstain() {
1914        // A nested destructure (`{ a: { x } }`) cannot be flattened. Abstain.
1915        let info = &svelte_props(r"<script>let { a: { x } } = $props();</script>")[0];
1916        assert!(info.has_unharvestable_props);
1917    }
1918
1919    #[test]
1920    fn svelte_prop_used_only_in_markup_credited_as_template_root() {
1921        // AC-8: a prop used only in markup (`{a}`) is credited via
1922        // `apply_template_usage`, so `used_in_template` is set (parity with Vue).
1923        let info = &svelte_props(r"<script>let { a } = $props();</script><p>{a}</p>")[0];
1924        assert_eq!(prop_names(info), vec!["a"]);
1925        assert!(
1926            info.component_props[0].used_in_template,
1927            "a is used in markup, so used_in_template should be true"
1928        );
1929    }
1930
1931    #[test]
1932    fn svelte_module_script_props_not_harvested() {
1933        // `$props()` is instance-only; a module-context script must not harvest.
1934        let info = &svelte_props(
1935            r"<script module>let { a } = $props();</script><script>let { b } = $props();</script>",
1936        )[0];
1937        // Only the instance script's `b` is harvested.
1938        assert_eq!(prop_names(info), vec!["b"]);
1939    }
1940
1941    // -- Svelte custom-event dispatch harvest (unused-svelte-event) ------------
1942
1943    fn dispatched_names(info: &crate::ModuleInfo) -> Vec<String> {
1944        let mut names: Vec<String> = info
1945            .svelte_dispatched_events
1946            .iter()
1947            .map(|e| e.name.clone())
1948            .collect();
1949        names.sort();
1950        names
1951    }
1952
1953    #[test]
1954    fn svelte_dispatch_literal_event_is_harvested() {
1955        let info = &svelte_props(
1956            r"<script>import { createEventDispatcher } from 'svelte';
1957              const dispatch = createEventDispatcher();
1958              function save() { dispatch('save'); }</script>",
1959        )[0];
1960        assert_eq!(dispatched_names(info), vec!["save"]);
1961        assert!(!info.has_dynamic_dispatch);
1962    }
1963
1964    #[test]
1965    fn svelte_dispatch_without_svelte_import_is_ignored() {
1966        // A local `createEventDispatcher` not imported from `svelte` is not a
1967        // dispatcher; the `dispatch('save')` call records nothing.
1968        let info = &svelte_props(
1969            r"<script>function createEventDispatcher() { return () => {}; }
1970              const dispatch = createEventDispatcher();
1971              dispatch('save');</script>",
1972        )[0];
1973        assert!(info.svelte_dispatched_events.is_empty());
1974    }
1975
1976    #[test]
1977    fn svelte_dynamic_dispatch_sets_abstain() {
1978        let info = &svelte_props(
1979            r"<script>import { createEventDispatcher } from 'svelte';
1980              const dispatch = createEventDispatcher();
1981              function fire(name) { dispatch(name); }</script>",
1982        )[0];
1983        assert!(
1984            info.has_dynamic_dispatch,
1985            "a non-literal dispatch arg must set the abstain flag"
1986        );
1987    }
1988
1989    #[test]
1990    fn svelte_dispatch_whole_value_use_sets_abstain() {
1991        let info = &svelte_props(
1992            r"<script>import { createEventDispatcher } from 'svelte';
1993              const dispatch = createEventDispatcher();
1994              forward(dispatch);</script>",
1995        )[0];
1996        assert!(
1997            info.has_dynamic_dispatch,
1998            "passing the dispatch binding as a whole value must set the abstain flag"
1999        );
2000    }
2001
2002    #[test]
2003    fn svelte_listened_event_on_component_is_harvested() {
2004        let info =
2005            &svelte_props(r"<script>import Child from './Child.svelte';</script><Child on:save />")
2006                [0];
2007        assert!(info.svelte_listened_events.contains(&"save".to_string()));
2008    }
2009}
fallow_extract/sfc.rs

fallow_extract/
sfc.rs
