fix(analyzers): restore C# support, fix return types, improve delegation heuristic

- Restore C# analyzer registration in SourceAnalyzer (removed unintentionally)
- Fix resolve_symbol return type annotation in Java/Python analyzers (-> list[Entity])
- Improve Kotlin delegation specifier handling: use constructor_invocation as
  class signal instead of blindly treating first specifier as base_class

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: gkorland

api/analyzers/java/analyzer.py

@@ -120,7 +120,7 @@ def resolve_method(self, files: dict[Path, File], lsp: SyncLanguageServer, file_
                 res.append(file.entities[method_dec])
         return res
 
-    def resolve_symbol(self, files: dict[Path, File], lsp: SyncLanguageServer, file_path: Path, path: Path, key: str, symbol: Node) -> Entity:
+    def resolve_symbol(self, files: dict[Path, File], lsp: SyncLanguageServer, file_path: Path, path: Path, key: str, symbol: Node) -> list[Entity]:
         if key in ["implement_interface", "base_class", "extend_interface", "parameters", "return_type"]:
             return self.resolve_type(files, lsp, file_path, path, symbol)
         elif key in ["call"]:

api/analyzers/kotlin/analyzer.py

@@ -59,8 +59,12 @@ def get_entity_docstring(self, node: Node) -> Optional[str]:
     def get_entity_types(self) -> list[str]:
         return ['class_declaration', 'object_declaration', 'function_declaration']
 
-    def _get_delegation_types(self, entity: Entity) -> list:
-        """Extract type identifiers from delegation specifiers in order."""
+    def _get_delegation_types(self, entity: Entity) -> list[tuple]:
+        """Extract type identifiers from delegation specifiers in order.
+        
+        Returns list of (node, is_constructor_invocation) tuples.
+        constructor_invocation indicates a superclass; plain user_type indicates an interface.
+        """
         types = []
         for child in entity.node.children:
             if child.type == 'delegation_specifiers':
@@ -72,27 +76,26 @@ def _get_delegation_types(self, entity: Entity) -> list:
                                     if s.type == 'user_type':
                                         for id_node in s.children:
                                             if id_node.type == 'identifier':
-                                                types.append(id_node)
+                                                types.append((id_node, True))
                             elif sub.type == 'user_type':
                                 for id_node in sub.children:
                                     if id_node.type == 'identifier':
-                                        types.append(id_node)
+                                        types.append((id_node, False))
         return types
 
     def add_symbols(self, entity: Entity) -> None:
         if entity.node.type == 'class_declaration':
             types = self._get_delegation_types(entity)
-            if types:
-                # First one is the superclass (base_class)
-                entity.add_symbol("base_class", types[0])
-                # Remaining are interfaces
-                for iface in types[1:]:
-                    entity.add_symbol("implement_interface", iface)
+            for node, is_class in types:
+                if is_class:
+                    entity.add_symbol("base_class", node)
+                else:
+                    entity.add_symbol("implement_interface", node)
 
         elif entity.node.type == 'object_declaration':
             types = self._get_delegation_types(entity)
-            for t in types:
-                entity.add_symbol("implement_interface", t)
+            for node, _ in types:
+                entity.add_symbol("implement_interface", node)
 
         elif entity.node.type == 'function_declaration':
             # Find function calls

api/analyzers/python/analyzer.py

@@ -115,7 +115,7 @@ def resolve_method(self, files: dict[Path, File], lsp: SyncLanguageServer, file_
                 res.append(file.entities[method_dec])
         return res
 
-    def resolve_symbol(self, files: dict[Path, File], lsp: SyncLanguageServer, file_path: Path, path: Path, key: str, symbol: Node) -> Entity:
+    def resolve_symbol(self, files: dict[Path, File], lsp: SyncLanguageServer, file_path: Path, path: Path, key: str, symbol: Node) -> list[Entity]:
         if key in ["base_class", "parameters", "return_type"]:
             return self.resolve_type(files, lsp, file_path, path, symbol)
         elif key in ["call"]:

api/analyzers/source_analyzer.py

@@ -8,6 +8,7 @@
 from ..graph import Graph
 from .analyzer import AbstractAnalyzer
 # from .c.analyzer import CAnalyzer
+from .csharp.analyzer import CSharpAnalyzer
 from .java.analyzer import JavaAnalyzer
 from .kotlin.analyzer import KotlinAnalyzer
 from .python.analyzer import PythonAnalyzer
@@ -26,6 +27,7 @@
     # '.h': CAnalyzer(),
     '.py': PythonAnalyzer(),
     '.java': JavaAnalyzer(),
+    '.cs': CSharpAnalyzer(),
     '.kt': KotlinAnalyzer(),
     '.kts': KotlinAnalyzer()}
 
@@ -139,14 +141,15 @@ def second_pass(self, graph: Graph, files: list[Path], path: Path) -> None:
             lsps[".py"] = SyncLanguageServer.create(config, logger, str(path))
         else:
             lsps[".py"] = NullLanguageServer()
-        if any(path.rglob('*.kt')) or any(path.rglob('*.kts')):
-            # For now, use NullLanguageServer for Kotlin as we need to set up kotlin-language-server
-            lsps[".kt"] = NullLanguageServer()
-            lsps[".kts"] = NullLanguageServer()
+        if any(path.rglob('*.cs')):
+            config = MultilspyConfig.from_dict({"code_language": "csharp"})
+            lsps[".cs"] = SyncLanguageServer.create(config, logger, str(path))
         else:
-            lsps[".kt"] = NullLanguageServer()
-            lsps[".kts"] = NullLanguageServer()
-        with lsps[".java"].start_server(), lsps[".py"].start_server(), lsps[".kt"].start_server(), lsps[".kts"].start_server():
+            lsps[".cs"] = NullLanguageServer()
+        # For now, use NullLanguageServer for Kotlin as kotlin-language-server setup is not yet integrated
+        lsps[".kt"] = NullLanguageServer()
+        lsps[".kts"] = NullLanguageServer()
+        with lsps[".java"].start_server(), lsps[".py"].start_server(), lsps[".cs"].start_server(), lsps[".kt"].start_server(), lsps[".kts"].start_server():
             files_len = len(self.files)
             for i, file_path in enumerate(files):
                 file = self.files[file_path]
@@ -174,7 +177,7 @@ def analyze_files(self, files: list[Path], path: Path, graph: Graph) -> None:
 
     def analyze_sources(self, path: Path, ignore: list[str], graph: Graph) -> None:
         path = path.resolve()
-        files = list(path.rglob("*.java")) + list(path.rglob("*.py")) + list(path.rglob("*.kt")) + list(path.rglob("*.kts"))
+        files = list(path.rglob("*.java")) + list(path.rglob("*.py")) + list(path.rglob("*.cs")) + list(path.rglob("*.kt")) + list(path.rglob("*.kts"))
         # First pass analysis of the source code
         self.first_pass(path, files, ignore, graph)