Merge pull request #281 from DevanshuNEU/fix/graceful-ts-parser-import

HOTFIX: graceful fallback when tree-sitter-typescript not installed

Author: DevanshuNEU

backend/services/dependency_analyzer.py

@@ -9,7 +9,11 @@
 # Tree-sitter
 import tree_sitter_python as tspython
 import tree_sitter_javascript as tsjavascript
-import tree_sitter_typescript as tstypescript
+try:
+    import tree_sitter_typescript as tstypescript
+    _HAS_TS_PARSER = True
+except ModuleNotFoundError:
+    _HAS_TS_PARSER = False
 from tree_sitter import Language, Parser
 
 from services.observability import logger, metrics
@@ -19,14 +23,24 @@ class DependencyAnalyzer:
     """Analyze code dependencies and build dependency graph"""
 
     def __init__(self):
-        # Initialize parsers
+        js_lang = Language(tsjavascript.language())
+        # Use proper TS parser if available, fall back to JS parser
+        if _HAS_TS_PARSER:
+            ts_lang = Language(tstypescript.language_typescript())
+            tsx_lang = Language(tstypescript.language_tsx())
+        else:
+            logger.warning("tree-sitter-typescript not installed, falling back to JS parser for TS/TSX")
+            ts_lang = js_lang
+            tsx_lang = js_lang
+
+        self.has_ts_parser = _HAS_TS_PARSER
         self.parsers = {
             'python': Parser(Language(tspython.language())),
-            'javascript': Parser(Language(tsjavascript.language())),
-            'typescript': Parser(Language(tstypescript.language_typescript())),
-            'tsx': Parser(Language(tstypescript.language_tsx())),
+            'javascript': Parser(js_lang),
+            'typescript': Parser(ts_lang),
+            'tsx': Parser(tsx_lang),
         }
-        logger.info("DependencyAnalyzer initialized")
+        logger.info("DependencyAnalyzer initialized", ts_parser=self.has_ts_parser)
 
     def _detect_language(self, file_path: str) -> str:
         """Detect language from file extension"""

backend/tests/test_dependency_analyzer.py

@@ -103,6 +103,23 @@ def test_ts_parser_is_not_js(self, analyzer):
         # They should be different Language objects
         assert ts_parser is not js_parser
 
+    def test_has_ts_parser_flag(self, analyzer):
+        assert analyzer.has_ts_parser is True
+
+    def test_fallback_when_ts_parser_missing(self, monkeypatch, tmp_path):
+        """App must not crash if tree-sitter-typescript is missing"""
+        import services.dependency_analyzer as mod
+        monkeypatch.setattr(mod, '_HAS_TS_PARSER', False)
+        from services.dependency_analyzer import DependencyAnalyzer
+        fallback = DependencyAnalyzer()
+        # Should initialize without error
+        assert fallback.has_ts_parser is False
+        # Should still parse TS files (using JS fallback)
+        ts_file = tmp_path / "test.ts"
+        ts_file.write_text('import { foo } from "./bar"')
+        result = fallback.analyze_file_dependencies(str(ts_file))
+        assert './bar' in result['imports']
+
 
 class TestLanguageDetection:
     """Verify file extension to language mapping"""