perf: forward langId hint to native standalone analysis functions

Pass the JS-resolved langId as an explicit Option<String> to the three
native standalone analysis functions (analyzeComplexity, buildCfgAnalysis,
extractDataflowAnalysis). Rust now uses the hint as the primary language,
falling back to extension detection only when None.

This ensures files whose language is inferred by content rather than
extension (e.g. .vue files tagged as "javascript", extensionless shebang
files) use the native Rust path instead of silently falling back to WASM.

Closes #739

Author: carlos-alm

crates/codegraph-core/src/analysis.rs

@@ -44,8 +44,18 @@ fn collect_function_nodes<'a>(
 }
 
 /// Parse source code and return a tree + language kind, or None if unsupported.
-fn parse_source(source: &str, file_path: &str) -> Option<(tree_sitter::Tree, LanguageKind)> {
-    let lang = LanguageKind::from_extension(file_path)?;
+/// When `lang_id` is provided, it is used as the primary language hint (supports
+/// files whose language is inferred by content rather than extension, e.g. `.vue`
+/// files tagged as `"javascript"` or extension-less files with a shebang).
+/// Falls back to extension detection when `lang_id` is `None`.
+fn parse_source(
+    source: &str,
+    file_path: &str,
+    lang_id: Option<&str>,
+) -> Option<(tree_sitter::Tree, LanguageKind)> {
+    let lang = lang_id
+        .and_then(LanguageKind::from_lang_id)
+        .or_else(|| LanguageKind::from_extension(file_path))?;
     let mut parser = Parser::new();
     parser.set_language(&lang.tree_sitter_language()).ok()?;
     let tree = parser.parse(source.as_bytes(), None)?;
@@ -57,8 +67,9 @@ fn parse_source(source: &str, file_path: &str) -> Option<(tree_sitter::Tree, Lan
 pub fn analyze_complexity_standalone(
     source: &str,
     file_path: &str,
+    lang_id: Option<&str>,
 ) -> Vec<FunctionComplexityResult> {
-    let (tree, lang) = match parse_source(source, file_path) {
+    let (tree, lang) = match parse_source(source, file_path, lang_id) {
         Some(v) => v,
         None => return Vec::new(),
     };
@@ -91,8 +102,8 @@ pub fn analyze_complexity_standalone(
 
 /// Build control-flow graphs for all functions in the given source.
 /// Returns per-function results with name, line, and CFG data.
-pub fn build_cfg_standalone(source: &str, file_path: &str) -> Vec<FunctionCfgResult> {
-    let (tree, lang) = match parse_source(source, file_path) {
+pub fn build_cfg_standalone(source: &str, file_path: &str, lang_id: Option<&str>) -> Vec<FunctionCfgResult> {
+    let (tree, lang) = match parse_source(source, file_path, lang_id) {
         Some(v) => v,
         None => return Vec::new(),
     };
@@ -130,7 +141,7 @@ pub fn build_cfg_standalone(source: &str, file_path: &str) -> Vec<FunctionCfgRes
 
 /// Extract dataflow analysis for the given source.
 /// Returns file-level dataflow result (parameters, returns, assignments, arg flows, mutations).
-pub fn extract_dataflow_standalone(source: &str, file_path: &str) -> Option<DataflowResult> {
-    let (tree, lang) = parse_source(source, file_path)?;
+pub fn extract_dataflow_standalone(source: &str, file_path: &str, lang_id: Option<&str>) -> Option<DataflowResult> {
+    let (tree, lang) = parse_source(source, file_path, lang_id)?;
     extract_dataflow(&tree, source.as_bytes(), lang.lang_id_str())
 }

crates/codegraph-core/src/lib.rs

@@ -129,30 +129,36 @@ pub fn engine_version() -> String {
 
 /// Analyze complexity metrics for all functions in the given source.
 /// Returns per-function results (name, line, endLine, complexity metrics).
-/// Language is detected from the file extension or treated as a lang_id.
+/// When `lang_id` is provided, it takes priority over extension-based detection.
 #[napi]
 pub fn analyze_complexity(
     source: String,
     file_path: String,
+    lang_id: Option<String>,
 ) -> Vec<types::FunctionComplexityResult> {
-    analysis::analyze_complexity_standalone(&source, &file_path)
+    analysis::analyze_complexity_standalone(&source, &file_path, lang_id.as_deref())
 }
 
 /// Build control-flow graphs for all functions in the given source.
 /// Returns per-function results (name, line, endLine, CFG blocks + edges).
-/// Language is detected from the file extension or treated as a lang_id.
+/// When `lang_id` is provided, it takes priority over extension-based detection.
 #[napi]
-pub fn build_cfg_analysis(source: String, file_path: String) -> Vec<types::FunctionCfgResult> {
-    analysis::build_cfg_standalone(&source, &file_path)
+pub fn build_cfg_analysis(
+    source: String,
+    file_path: String,
+    lang_id: Option<String>,
+) -> Vec<types::FunctionCfgResult> {
+    analysis::build_cfg_standalone(&source, &file_path, lang_id.as_deref())
 }
 
 /// Extract dataflow analysis for the given source.
 /// Returns file-level dataflow (parameters, returns, assignments, arg flows, mutations).
-/// Language is detected from the file extension or treated as a lang_id.
+/// When `lang_id` is provided, it takes priority over extension-based detection.
 #[napi]
 pub fn extract_dataflow_analysis(
     source: String,
     file_path: String,
+    lang_id: Option<String>,
 ) -> Option<types::DataflowResult> {
-    analysis::extract_dataflow_standalone(&source, &file_path)
+    analysis::extract_dataflow_standalone(&source, &file_path, lang_id.as_deref())
 }

src/ast-analysis/engine.ts

@@ -151,7 +151,7 @@ function runNativeAnalysis(
     // Complexity
     if (needsComplexity && native.analyzeComplexity) {
       try {
-        const results = native.analyzeComplexity(source, absPath);
+        const results = native.analyzeComplexity(source, absPath, langId);
         storeNativeComplexityResults(results, defs);
       } catch (err: unknown) {
         debug(`native analyzeComplexity failed for ${relPath}: ${(err as Error).message}`);
@@ -161,7 +161,7 @@ function runNativeAnalysis(
     // CFG
     if (needsCfg && native.buildCfgAnalysis) {
       try {
-        const results = native.buildCfgAnalysis(source, absPath);
+        const results = native.buildCfgAnalysis(source, absPath, langId);
         storeNativeCfgResults(results, defs);
       } catch (err: unknown) {
         debug(`native buildCfgAnalysis failed for ${relPath}: ${(err as Error).message}`);
@@ -171,7 +171,7 @@ function runNativeAnalysis(
     // Dataflow
     if (needsDataflow && native.extractDataflowAnalysis) {
       try {
-        const result = native.extractDataflowAnalysis(source, absPath);
+        const result = native.extractDataflowAnalysis(source, absPath, langId);
         if (result) symbols.dataflow = result;
       } catch (err: unknown) {
         debug(`native extractDataflowAnalysis failed for ${relPath}: ${(err as Error).message}`);

src/types.ts

@@ -1874,9 +1874,21 @@ export interface NativeAddon {
     rootDir: string,
   ): unknown[];
   engineVersion(): string;
-  analyzeComplexity(source: string, filePath: string): NativeFunctionComplexityResult[];
-  buildCfgAnalysis(source: string, filePath: string): NativeFunctionCfgResult[];
-  extractDataflowAnalysis(source: string, filePath: string): DataflowResult | null;
+  analyzeComplexity(
+    source: string,
+    filePath: string,
+    langId?: string | null,
+  ): NativeFunctionComplexityResult[];
+  buildCfgAnalysis(
+    source: string,
+    filePath: string,
+    langId?: string | null,
+  ): NativeFunctionCfgResult[];
+  extractDataflowAnalysis(
+    source: string,
+    filePath: string,
+    langId?: string | null,
+  ): DataflowResult | null;
   ParseTreeCache: new () => NativeParseTreeCache;
   NativeDatabase: {
     openReadWrite(dbPath: string): NativeDatabase;