feat: add Dart/Flutter language support

gitnexus/package.json

@@ -46,7 +46,7 @@
     "test:watch": "vitest",
     "test:coverage": "vitest run --coverage",
     "prepare": "npm run build",
-    "postinstall": "node scripts/patch-tree-sitter-swift.cjs",
+    "postinstall": "node scripts/patch-tree-sitter-swift.cjs && node scripts/patch-tree-sitter-dart.cjs",
     "prepack": "npm run build && chmod +x dist/cli/index.js"
   },
   "dependencies": {
@@ -81,6 +81,7 @@
     "uuid": "^13.0.0"
   },
   "optionalDependencies": {
+    "tree-sitter-dart": "^1.0.0",
     "tree-sitter-kotlin": "^0.3.8",
     "tree-sitter-swift": "0.7.1"
   },

gitnexus/scripts/patch-tree-sitter-dart.cjs

@@ -0,0 +1,119 @@
+#!/usr/bin/env node
+/**
+ * WORKAROUND: tree-sitter-dart@1.0.0 NAN → NAPI binding conversion
+ *
+ * Background:
+ *   tree-sitter-dart@1.0.0 uses NAN (Native Abstractions for Node.js) for its
+ *   native binding. NAN modules fail with "Module did not self-register" when
+ *   loaded in Node.js worker_threads alongside NAPI-based tree-sitter modules.
+ *   All other tree-sitter grammars in this project use NAPI, which is thread-safe.
+ *
+ * How this workaround works:
+ *   1. Replaces the NAN-based binding.cc with a NAPI-based one
+ *   2. Updates binding.gyp to use node-addon-api instead of nan
+ *   3. Installs node-addon-api as a local dependency
+ *   4. Rebuilds the native binding
+ *
+ * TODO: Remove this script when tree-sitter-dart publishes a version with NAPI
+ *       bindings (or when an alternative package is available).
+ */
+const fs = require('fs');
+const path = require('path');
+const { execSync } = require('child_process');
+
+const dartDir = path.join(__dirname, '..', 'node_modules', 'tree-sitter-dart');
+const bindingCcPath = path.join(dartDir, 'bindings', 'node', 'binding.cc');
+const bindingGypPath = path.join(dartDir, 'binding.gyp');
+
+const NAPI_BINDING_CC = `#include <napi.h>
+
+typedef struct TSLanguage TSLanguage;
+
+extern "C" TSLanguage *tree_sitter_dart();
+
+// "tree-sitter", "language" hashed with BLAKE2
+const napi_type_tag LANGUAGE_TYPE_TAG = {
+  0x8AF2E5212AD58ABF, 0xD5006CAD83ABBA16
+};
+
+Napi::Object Init(Napi::Env env, Napi::Object exports) {
+    exports["name"] = Napi::String::New(env, "dart");
+    auto language = Napi::External<TSLanguage>::New(env, tree_sitter_dart());
+    language.TypeTag(&LANGUAGE_TYPE_TAG);
+    exports["language"] = language;
+    return exports;
+}
+
+NODE_API_MODULE(tree_sitter_dart_binding, Init)
+`;
+
+const NAPI_BINDING_GYP = `{
+  "targets": [
+    {
+      "target_name": "tree_sitter_dart_binding",
+      "dependencies": [
+        "<!(node -p \\"require('node-addon-api').targets\\"):node_addon_api_except"
+      ],
+      "include_dirs": [
+        "src"
+      ],
+      "sources": [
+        "bindings/node/binding.cc",
+        "src/parser.c",
+        "src/scanner.c"
+      ],
+      "cflags_c": [
+        "-std=c99"
+      ]
+    }
+  ]
+}
+`;
+
+try {
+  if (!fs.existsSync(bindingCcPath)) {
+    process.exit(0);
+  }
+
+  const currentBinding = fs.readFileSync(bindingCcPath, 'utf8');
+  let needsRebuild = false;
+
+  // Check if still using NAN
+  if (currentBinding.includes('nan.h')) {
+    console.log('[tree-sitter-dart] Converting NAN binding to NAPI for worker_threads compatibility...');
+    fs.writeFileSync(bindingCcPath, NAPI_BINDING_CC);
+    fs.writeFileSync(bindingGypPath, NAPI_BINDING_GYP);
+    needsRebuild = true;
+
+    // Install node-addon-api if not present
+    const napiDir = path.join(dartDir, 'node_modules', 'node-addon-api');
+    if (!fs.existsSync(napiDir)) {
+      console.log('[tree-sitter-dart] Installing node-addon-api...');
+      execSync('npm install node-addon-api', {
+        cwd: dartDir,
+        stdio: 'pipe',
+        timeout: 60000,
+      });
+    }
+  }
+
+  // Check if native binding exists
+  const bindingNode = path.join(dartDir, 'build', 'Release', 'tree_sitter_dart_binding.node');
+  if (!fs.existsSync(bindingNode)) {
+    needsRebuild = true;
+  }
+
+  if (needsRebuild) {
+    console.log('[tree-sitter-dart] Rebuilding native binding with NAPI...');
+    execSync('npx node-gyp rebuild', {
+      cwd: dartDir,
+      stdio: 'pipe',
+      timeout: 120000,
+    });
+    console.log('[tree-sitter-dart] NAPI binding built successfully');
+  }
+} catch (err) {
+  console.warn('[tree-sitter-dart] Could not build NAPI binding:', err.message);
+  console.warn('[tree-sitter-dart] Dart support will be unavailable in worker threads.');
+  console.warn('[tree-sitter-dart] You may need to manually run: cd node_modules/tree-sitter-dart && npx node-gyp rebuild');
+}

gitnexus/src/config/supported-languages.ts

@@ -41,4 +41,5 @@ export enum SupportedLanguages {
     PHP = 'php',
     Kotlin = 'kotlin',
     Swift = 'swift',
+    Dart = 'dart',
 }

gitnexus/src/core/ingestion/entry-point-scoring.ts

@@ -212,6 +212,21 @@ export const ENTRY_POINT_PATTERNS = {
     /^perform$/,              // Background jobs (Sidekiq, ActiveJob)
     /^execute$/,              // Command pattern
   ],
+
+  // Dart / Flutter
+  [SupportedLanguages.Dart]: [
+    /^main$/,                 // THE entry point
+    /^build$/,                // Widget.build() method
+    /^initState$/,            // StatefulWidget lifecycle
+    /^dispose$/,              // Cleanup lifecycle
+    /^createState$/,          // StatefulWidget.createState()
+    /Widget$/,                // Custom widget classes
+    /Page$/,                  // Page classes
+    /Screen$/,                // Screen classes
+    /Controller$/,            // Controllers
+    /Notifier$/,              // Riverpod notifiers
+    /Provider$/,              // Provider pattern
+  ],
 } satisfies Record<SupportedLanguages, RegExp[]>;
 
 /** Pre-computed merged patterns (universal + language-specific) to avoid per-call array allocation. */
@@ -378,6 +393,8 @@ export function isTestFile(filePath: string): boolean {
     p.includes('.integrationtests/') ||
     p.includes('.unittests/') ||
     p.includes('/testproject/') ||
+    // Dart/Flutter test patterns
+    p.endsWith('_test.dart') ||
     // PHP/Laravel test patterns
     p.endsWith('test.php') ||
     p.endsWith('spec.php') ||

gitnexus/src/core/ingestion/export-detection.ts

@@ -217,3 +217,5 @@ export const swiftExportChecker: ExportChecker = (node, _name) => {
 /** Ruby: all top-level definitions are public (no export syntax). */
 export const rubyExportChecker: ExportChecker = (_node, _name) => true;
 
+/** Dart: names starting with _ are library-private, everything else is public. */
+export const dartExportChecker: ExportChecker = (_node, name) => !name.startsWith('_');

gitnexus/src/core/ingestion/framework-detection.ts

@@ -406,6 +406,38 @@ export function detectFrameworkFromPath(filePath: string): FrameworkHint | null
     return { framework: 'ios-router', entryPointMultiplier: 2.0, reason: 'ios-router' };
   }
 
+  // ========== DART / FLUTTER ==========
+
+  // Flutter main entry point
+  if (p.endsWith('/main.dart') || p.endsWith('/app.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 3.0, reason: 'flutter-main' };
+  }
+
+  // Flutter pages/screens (high confidence entry points)
+  if ((p.includes('/pages/') || p.includes('/screens/') || p.includes('/views/')) && p.endsWith('.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 2.5, reason: 'flutter-page' };
+  }
+
+  // Flutter presentation layer (controllers, providers, notifiers)
+  if (p.includes('/presentation/') && p.endsWith('.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 2.0, reason: 'flutter-presentation' };
+  }
+
+  // Flutter routes
+  if (p.includes('/routes/') && p.endsWith('.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 2.5, reason: 'flutter-routes' };
+  }
+
+  // Flutter widgets (moderate - reusable components)
+  if (p.includes('/widgets/') && p.endsWith('.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 1.5, reason: 'flutter-widget' };
+  }
+
+  // Flutter domain/services (moderate)
+  if ((p.includes('/domain/') || p.includes('/services/')) && p.endsWith('.dart')) {
+    return { framework: 'flutter', entryPointMultiplier: 1.8, reason: 'flutter-domain' };
+  }
+
   // ========== GENERIC PATTERNS ==========
 
   // Any language: index files in API folders
@@ -478,6 +510,10 @@ export const FRAMEWORK_AST_PATTERNS = {
   'rails': ['ApplicationController', 'ApplicationRecord', 'ActiveRecord::Base',
             'before_action', 'after_action', 'has_many', 'belongs_to', 'has_one', 'validates'],
   'sinatra': ['Sinatra::Base', 'Sinatra::Application'],
+
+  // Dart/Flutter
+  'flutter': ['@override', 'Widget build', 'StatelessWidget', 'StatefulWidget', 'ConsumerWidget'],
+  'riverpod': ['@riverpod', 'ref.watch', 'ref.read', 'AsyncNotifier', 'Notifier'],
 };
 
 interface AstFrameworkPatternConfig {
@@ -545,6 +581,10 @@ export const AST_FRAMEWORK_PATTERNS_BY_LANGUAGE = {
     { framework: 'rails', entryPointMultiplier: 3.0, reason: 'rails-pattern', patterns: FRAMEWORK_AST_PATTERNS.rails },
     { framework: 'sinatra', entryPointMultiplier: 2.8, reason: 'sinatra-pattern', patterns: FRAMEWORK_AST_PATTERNS.sinatra },
   ],
+  [SupportedLanguages.Dart]: [
+    { framework: 'flutter', entryPointMultiplier: 2.5, reason: 'flutter-widget', patterns: FRAMEWORK_AST_PATTERNS.flutter },
+    { framework: 'riverpod', entryPointMultiplier: 2.8, reason: 'riverpod-provider', patterns: FRAMEWORK_AST_PATTERNS.riverpod },
+  ],
 } satisfies Record<SupportedLanguages, AstFrameworkPatternConfig[]>;
 
 /** Pre-lowercased patterns for O(1) pattern matching at runtime */