fallow_extract/
sfc.rs

1//! Vue/Svelte Single File Component (SFC) script extraction.
2//!
3//! Extracts `<script>` block content from `.vue` and `.svelte` files using regex,
4//! handling `lang`, `src`, and `generic` attributes, and filtering HTML comments.
5
6use std::path::Path;
7use std::sync::LazyLock;
8
9use oxc_allocator::Allocator;
10use oxc_ast_visit::Visit;
11use oxc_parser::Parser;
12use oxc_span::SourceType;
13
14use crate::visitor::ModuleInfoExtractor;
15use crate::{ImportInfo, ImportedName, ModuleInfo};
16use fallow_types::discover::FileId;
17use oxc_span::Span;
18
19/// Regex to extract `<script>` block content from Vue/Svelte SFCs.
20/// The attrs pattern handles `>` inside quoted attribute values (e.g., `generic="T extends Foo<Bar>"`).
21static SCRIPT_BLOCK_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
22    regex::Regex::new(
23        r#"(?is)<script\b(?P<attrs>(?:[^>"']|"[^"]*"|'[^']*')*)>(?P<body>[\s\S]*?)</script>"#,
24    )
25    .expect("valid regex")
26});
27
28/// Regex to extract the `lang` attribute value from a script tag.
29static LANG_ATTR_RE: LazyLock<regex::Regex> =
30    LazyLock::new(|| regex::Regex::new(r#"lang\s*=\s*["'](\w+)["']"#).expect("valid regex"));
31
32/// Regex to extract the `src` attribute value from a script tag.
33/// Requires whitespace (or start of string) before `src` to avoid matching `data-src` etc.
34static SRC_ATTR_RE: LazyLock<regex::Regex> = LazyLock::new(|| {
35    regex::Regex::new(r#"(?:^|\s)src\s*=\s*["']([^"']+)["']"#).expect("valid regex")
36});
37
38/// Regex to match HTML comments for filtering script blocks inside comments.
39static HTML_COMMENT_RE: LazyLock<regex::Regex> =
40    LazyLock::new(|| regex::Regex::new(r"(?s)<!--.*?-->").expect("valid regex"));
41
42/// An extracted `<script>` block from a Vue or Svelte SFC.
43pub struct SfcScript {
44    /// The script body text.
45    pub body: String,
46    /// Whether the script uses TypeScript (`lang="ts"` or `lang="tsx"`).
47    pub is_typescript: bool,
48    /// Whether the script uses JSX syntax (`lang="tsx"` or `lang="jsx"`).
49    pub is_jsx: bool,
50    /// Byte offset of the script body within the full SFC source.
51    pub byte_offset: usize,
52    /// External script source path from `src` attribute.
53    pub src: Option<String>,
54}
55
56/// Extract all `<script>` blocks from a Vue/Svelte SFC source string.
57pub fn extract_sfc_scripts(source: &str) -> Vec<SfcScript> {
58    // Build HTML comment ranges to filter out <script> blocks inside comments.
59    // Using ranges instead of source replacement avoids corrupting script body content
60    // (e.g., string literals containing "<!--" would be destroyed by replacement).
61    let comment_ranges: Vec<(usize, usize)> = HTML_COMMENT_RE
62        .find_iter(source)
63        .map(|m| (m.start(), m.end()))
64        .collect();
65
66    SCRIPT_BLOCK_RE
67        .captures_iter(source)
68        .filter(|cap| {
69            let start = cap.get(0).map_or(0, |m| m.start());
70            !comment_ranges
71                .iter()
72                .any(|&(cs, ce)| start >= cs && start < ce)
73        })
74        .map(|cap| {
75            let attrs = cap.name("attrs").map_or("", |m| m.as_str());
76            let body_match = cap.name("body");
77            let byte_offset = body_match.map_or(0, |m| m.start());
78            let body = body_match.map_or("", |m| m.as_str()).to_string();
79            let lang = LANG_ATTR_RE
80                .captures(attrs)
81                .and_then(|c| c.get(1))
82                .map(|m| m.as_str());
83            let is_typescript = matches!(lang, Some("ts" | "tsx"));
84            let is_jsx = matches!(lang, Some("tsx" | "jsx"));
85            let src = SRC_ATTR_RE
86                .captures(attrs)
87                .and_then(|c| c.get(1))
88                .map(|m| m.as_str().to_string());
89            SfcScript {
90                body,
91                is_typescript,
92                is_jsx,
93                byte_offset,
94                src,
95            }
96        })
97        .collect()
98}
99
100/// Check if a file path is a Vue or Svelte SFC (`.vue` or `.svelte`).
101pub fn is_sfc_file(path: &Path) -> bool {
102    path.extension()
103        .and_then(|e| e.to_str())
104        .is_some_and(|ext| ext == "vue" || ext == "svelte")
105}
106
107/// Parse an SFC file by extracting and combining all `<script>` blocks.
108pub(crate) fn parse_sfc_to_module(file_id: FileId, source: &str, content_hash: u64) -> ModuleInfo {
109    let scripts = extract_sfc_scripts(source);
110
111    // For SFC files, use string scanning for suppression comments since script block
112    // byte offsets don't correspond to the original file positions.
113    let suppressions = crate::suppress::parse_suppressions_from_source(source);
114
115    let mut combined = ModuleInfo {
116        file_id,
117        exports: Vec::new(),
118        imports: Vec::new(),
119        re_exports: Vec::new(),
120        dynamic_imports: Vec::new(),
121        dynamic_import_patterns: Vec::new(),
122        require_calls: Vec::new(),
123        member_accesses: Vec::new(),
124        whole_object_uses: Vec::new(),
125        has_cjs_exports: false,
126        content_hash,
127        suppressions,
128        unused_import_bindings: Vec::new(),
129        line_offsets: fallow_types::extract::compute_line_offsets(source),
130        complexity: Vec::new(),
131    };
132
133    for script in &scripts {
134        if let Some(src) = &script.src {
135            combined.imports.push(ImportInfo {
136                source: src.clone(),
137                imported_name: ImportedName::SideEffect,
138                local_name: String::new(),
139                is_type_only: false,
140                span: Span::default(),
141                source_span: Span::default(),
142            });
143        }
144
145        let source_type = match (script.is_typescript, script.is_jsx) {
146            (true, true) => SourceType::tsx(),
147            (true, false) => SourceType::ts(),
148            (false, true) => SourceType::jsx(),
149            (false, false) => SourceType::mjs(),
150        };
151        let allocator = Allocator::default();
152        let parser_return = Parser::new(&allocator, &script.body, source_type).parse();
153        let mut extractor = ModuleInfoExtractor::new();
154        extractor.visit_program(&parser_return.program);
155        extractor.merge_into(&mut combined);
156    }
157
158    combined
159}
160
161// SFC tests exercise regex-based HTML string extraction — no unsafe code,
162// no Miri-specific value. Oxc parser tests are additionally ~1000x slower.
163#[cfg(all(test, not(miri)))]
164mod tests {
165    use super::*;
166
167    // ── is_sfc_file ──────────────────────────────────────────────
168
169    #[test]
170    fn is_sfc_file_vue() {
171        assert!(is_sfc_file(Path::new("App.vue")));
172    }
173
174    #[test]
175    fn is_sfc_file_svelte() {
176        assert!(is_sfc_file(Path::new("Counter.svelte")));
177    }
178
179    #[test]
180    fn is_sfc_file_rejects_ts() {
181        assert!(!is_sfc_file(Path::new("utils.ts")));
182    }
183
184    #[test]
185    fn is_sfc_file_rejects_jsx() {
186        assert!(!is_sfc_file(Path::new("App.jsx")));
187    }
188
189    #[test]
190    fn is_sfc_file_rejects_astro() {
191        assert!(!is_sfc_file(Path::new("Layout.astro")));
192    }
193
194    // ── extract_sfc_scripts: single script block ─────────────────
195
196    #[test]
197    fn single_plain_script() {
198        let scripts = extract_sfc_scripts("<script>const x = 1;</script>");
199        assert_eq!(scripts.len(), 1);
200        assert_eq!(scripts[0].body, "const x = 1;");
201        assert!(!scripts[0].is_typescript);
202        assert!(!scripts[0].is_jsx);
203        assert!(scripts[0].src.is_none());
204    }
205
206    #[test]
207    fn single_ts_script() {
208        let scripts = extract_sfc_scripts(r#"<script lang="ts">const x: number = 1;</script>"#);
209        assert_eq!(scripts.len(), 1);
210        assert!(scripts[0].is_typescript);
211        assert!(!scripts[0].is_jsx);
212    }
213
214    #[test]
215    fn single_tsx_script() {
216        let scripts = extract_sfc_scripts(r#"<script lang="tsx">const el = <div />;</script>"#);
217        assert_eq!(scripts.len(), 1);
218        assert!(scripts[0].is_typescript);
219        assert!(scripts[0].is_jsx);
220    }
221
222    #[test]
223    fn single_jsx_script() {
224        let scripts = extract_sfc_scripts(r#"<script lang="jsx">const el = <div />;</script>"#);
225        assert_eq!(scripts.len(), 1);
226        assert!(!scripts[0].is_typescript);
227        assert!(scripts[0].is_jsx);
228    }
229
230    // ── Multiple script blocks ───────────────────────────────────
231
232    #[test]
233    fn two_script_blocks() {
234        let source = r#"
235<script lang="ts">
236export default {};
237</script>
238<script setup lang="ts">
239const count = 0;
240</script>
241"#;
242        let scripts = extract_sfc_scripts(source);
243        assert_eq!(scripts.len(), 2);
244        assert!(scripts[0].body.contains("export default"));
245        assert!(scripts[1].body.contains("count"));
246    }
247
248    // ── <script setup> ───────────────────────────────────────────
249
250    #[test]
251    fn script_setup_extracted() {
252        let scripts =
253            extract_sfc_scripts(r#"<script setup lang="ts">import { ref } from 'vue';</script>"#);
254        assert_eq!(scripts.len(), 1);
255        assert!(scripts[0].body.contains("import"));
256        assert!(scripts[0].is_typescript);
257    }
258
259    // ── <script src="..."> external script ───────────────────────
260
261    #[test]
262    fn script_src_detected() {
263        let scripts = extract_sfc_scripts(r#"<script src="./component.ts" lang="ts"></script>"#);
264        assert_eq!(scripts.len(), 1);
265        assert_eq!(scripts[0].src.as_deref(), Some("./component.ts"));
266    }
267
268    #[test]
269    fn data_src_not_treated_as_src() {
270        let scripts =
271            extract_sfc_scripts(r#"<script lang="ts" data-src="./nope.ts">const x = 1;</script>"#);
272        assert_eq!(scripts.len(), 1);
273        assert!(scripts[0].src.is_none());
274    }
275
276    // ── HTML comment filtering ───────────────────────────────────
277
278    #[test]
279    fn script_inside_html_comment_filtered() {
280        let source = r#"
281<!-- <script lang="ts">import { bad } from 'bad';</script> -->
282<script lang="ts">import { good } from 'good';</script>
283"#;
284        let scripts = extract_sfc_scripts(source);
285        assert_eq!(scripts.len(), 1);
286        assert!(scripts[0].body.contains("good"));
287    }
288
289    #[test]
290    fn spanning_comment_filters_script() {
291        let source = r#"
292<!-- disabled:
293<script lang="ts">import { bad } from 'bad';</script>
294-->
295<script lang="ts">const ok = true;</script>
296"#;
297        let scripts = extract_sfc_scripts(source);
298        assert_eq!(scripts.len(), 1);
299        assert!(scripts[0].body.contains("ok"));
300    }
301
302    #[test]
303    fn string_containing_comment_markers_not_corrupted() {
304        // A string in the script body containing <!-- should not cause filtering issues
305        let source = r#"
306<script setup lang="ts">
307const marker = "<!-- not a comment -->";
308import { ref } from 'vue';
309</script>
310"#;
311        let scripts = extract_sfc_scripts(source);
312        assert_eq!(scripts.len(), 1);
313        assert!(scripts[0].body.contains("import"));
314    }
315
316    // ── Generic attributes with > in quoted values ───────────────
317
318    #[test]
319    fn generic_attr_with_angle_bracket() {
320        let source =
321            r#"<script setup lang="ts" generic="T extends Foo<Bar>">const x = 1;</script>"#;
322        let scripts = extract_sfc_scripts(source);
323        assert_eq!(scripts.len(), 1);
324        assert_eq!(scripts[0].body, "const x = 1;");
325    }
326
327    #[test]
328    fn nested_generic_attr() {
329        let source = r#"<script setup lang="ts" generic="T extends Map<string, Set<number>>">const x = 1;</script>"#;
330        let scripts = extract_sfc_scripts(source);
331        assert_eq!(scripts.len(), 1);
332        assert_eq!(scripts[0].body, "const x = 1;");
333    }
334
335    // ── lang attribute with single quotes ────────────────────────
336
337    #[test]
338    fn lang_single_quoted() {
339        let scripts = extract_sfc_scripts("<script lang='ts'>const x = 1;</script>");
340        assert_eq!(scripts.len(), 1);
341        assert!(scripts[0].is_typescript);
342    }
343
344    // ── Case-insensitive matching ────────────────────────────────
345
346    #[test]
347    fn uppercase_script_tag() {
348        let scripts = extract_sfc_scripts(r#"<SCRIPT lang="ts">const x = 1;</SCRIPT>"#);
349        assert_eq!(scripts.len(), 1);
350        assert!(scripts[0].is_typescript);
351    }
352
353    // ── Edge cases ───────────────────────────────────────────────
354
355    #[test]
356    fn no_script_block() {
357        let scripts = extract_sfc_scripts("<template><div>Hello</div></template>");
358        assert!(scripts.is_empty());
359    }
360
361    #[test]
362    fn empty_script_body() {
363        let scripts = extract_sfc_scripts(r#"<script lang="ts"></script>"#);
364        assert_eq!(scripts.len(), 1);
365        assert!(scripts[0].body.is_empty());
366    }
367
368    #[test]
369    fn whitespace_only_script() {
370        let scripts = extract_sfc_scripts("<script lang=\"ts\">\n  \n</script>");
371        assert_eq!(scripts.len(), 1);
372        assert!(scripts[0].body.trim().is_empty());
373    }
374
375    #[test]
376    fn byte_offset_is_set() {
377        let source = r#"<template><div/></template><script lang="ts">code</script>"#;
378        let scripts = extract_sfc_scripts(source);
379        assert_eq!(scripts.len(), 1);
380        // The byte_offset should point to where "code" starts in the source
381        let offset = scripts[0].byte_offset;
382        assert_eq!(&source[offset..offset + 4], "code");
383    }
384
385    #[test]
386    fn script_with_extra_attributes() {
387        let scripts = extract_sfc_scripts(
388            r#"<script lang="ts" id="app" type="module" data-custom="val">const x = 1;</script>"#,
389        );
390        assert_eq!(scripts.len(), 1);
391        assert!(scripts[0].is_typescript);
392        assert!(scripts[0].src.is_none());
393    }
394
395    // ── Full parse tests (Oxc parser ~1000x slower under Miri) ──
396
397    #[test]
398    fn multiple_script_blocks_exports_combined() {
399        let source = r#"
400<script lang="ts">
401export const version = '1.0';
402</script>
403<script setup lang="ts">
404import { ref } from 'vue';
405const count = ref(0);
406</script>
407"#;
408        let info = parse_sfc_to_module(FileId(0), source, 0);
409        // The non-setup block exports `version`
410        assert!(
411            info.exports
412                .iter()
413                .any(|e| matches!(&e.name, crate::ExportName::Named(n) if n == "version")),
414            "export from <script> block should be extracted"
415        );
416        // The setup block imports `ref` from 'vue'
417        assert!(
418            info.imports.iter().any(|i| i.source == "vue"),
419            "import from <script setup> block should be extracted"
420        );
421    }
422
423    // ── lang="tsx" detection ────────────────────────────────────
424
425    #[test]
426    fn lang_tsx_detected_as_typescript_jsx() {
427        let scripts =
428            extract_sfc_scripts(r#"<script lang="tsx">const el = <div>{x}</div>;</script>"#);
429        assert_eq!(scripts.len(), 1);
430        assert!(scripts[0].is_typescript, "lang=tsx should be typescript");
431        assert!(scripts[0].is_jsx, "lang=tsx should be jsx");
432    }
433
434    // ── HTML comment filtering of script blocks ─────────────────
435
436    #[test]
437    fn multiline_html_comment_filters_all_script_blocks_inside() {
438        let source = r#"
439<!--
440  This whole section is disabled:
441  <script lang="ts">import { bad1 } from 'bad1';</script>
442  <script lang="ts">import { bad2 } from 'bad2';</script>
443-->
444<script lang="ts">import { good } from 'good';</script>
445"#;
446        let scripts = extract_sfc_scripts(source);
447        assert_eq!(scripts.len(), 1);
448        assert!(scripts[0].body.contains("good"));
449    }
450
451    // ── <script src="..."> generates side-effect import ─────────
452
453    #[test]
454    fn script_src_generates_side_effect_import() {
455        let info = parse_sfc_to_module(
456            FileId(0),
457            r#"<script src="./external-logic.ts" lang="ts"></script>"#,
458            0,
459        );
460        assert!(
461            info.imports
462                .iter()
463                .any(|i| i.source == "./external-logic.ts"
464                    && matches!(i.imported_name, ImportedName::SideEffect)),
465            "script src should generate a side-effect import"
466        );
467    }
468
469    // ── Additional coverage ─────────────────────────────────────
470
471    #[test]
472    fn parse_sfc_no_script_returns_empty_module() {
473        let info = parse_sfc_to_module(FileId(0), "<template><div>Hello</div></template>", 42);
474        assert!(info.imports.is_empty());
475        assert!(info.exports.is_empty());
476        assert_eq!(info.content_hash, 42);
477        assert_eq!(info.file_id, FileId(0));
478    }
479
480    #[test]
481    fn parse_sfc_has_line_offsets() {
482        let info = parse_sfc_to_module(FileId(0), r#"<script lang="ts">const x = 1;</script>"#, 0);
483        assert!(!info.line_offsets.is_empty());
484    }
485
486    #[test]
487    fn parse_sfc_has_suppressions() {
488        let info = parse_sfc_to_module(
489            FileId(0),
490            r#"<script lang="ts">
491// fallow-ignore-file
492export const foo = 1;
493</script>"#,
494            0,
495        );
496        assert!(!info.suppressions.is_empty());
497    }
498
499    #[test]
500    fn source_type_jsx_detection() {
501        let scripts = extract_sfc_scripts(r#"<script lang="jsx">const el = <div />;</script>"#);
502        assert_eq!(scripts.len(), 1);
503        assert!(!scripts[0].is_typescript);
504        assert!(scripts[0].is_jsx);
505    }
506
507    #[test]
508    fn source_type_plain_js_detection() {
509        let scripts = extract_sfc_scripts("<script>const x = 1;</script>");
510        assert_eq!(scripts.len(), 1);
511        assert!(!scripts[0].is_typescript);
512        assert!(!scripts[0].is_jsx);
513    }
514
515    #[test]
516    fn is_sfc_file_rejects_no_extension() {
517        assert!(!is_sfc_file(Path::new("Makefile")));
518    }
519
520    #[test]
521    fn is_sfc_file_rejects_mdx() {
522        assert!(!is_sfc_file(Path::new("post.mdx")));
523    }
524
525    #[test]
526    fn is_sfc_file_rejects_css() {
527        assert!(!is_sfc_file(Path::new("styles.css")));
528    }
529
530    #[test]
531    fn multiple_script_blocks_both_have_offsets() {
532        let source = r#"<script lang="ts">const a = 1;</script>
533<script setup lang="ts">const b = 2;</script>"#;
534        let scripts = extract_sfc_scripts(source);
535        assert_eq!(scripts.len(), 2);
536        // Both scripts should have valid byte offsets
537        let offset0 = scripts[0].byte_offset;
538        let offset1 = scripts[1].byte_offset;
539        assert_eq!(
540            &source[offset0..offset0 + "const a = 1;".len()],
541            "const a = 1;"
542        );
543        assert_eq!(
544            &source[offset1..offset1 + "const b = 2;".len()],
545            "const b = 2;"
546        );
547    }
548
549    #[test]
550    fn script_with_src_and_lang() {
551        // src + lang should both be detected
552        let scripts = extract_sfc_scripts(r#"<script src="./logic.ts" lang="tsx"></script>"#);
553        assert_eq!(scripts.len(), 1);
554        assert_eq!(scripts[0].src.as_deref(), Some("./logic.ts"));
555        assert!(scripts[0].is_typescript);
556        assert!(scripts[0].is_jsx);
557    }
558}
fallow_extract/sfc.rs

fallow_extract/
sfc.rs
