Add textDocument/typeDefinition

src/messages/initialize.cc

@@ -137,6 +137,8 @@ struct lsServerCapabilities {
   lsSignatureHelpOptions signatureHelpProvider;
   // The server provides goto definition support.
   bool definitionProvider = true;
+  // The server provides Goto Type Definition support.
+  bool typeDefinitionProvider = true;
   // The server provides find references support.
   bool referencesProvider = true;
   // The server provides document highlight support.

src/messages/text_document_type_definition.cc

@@ -22,6 +22,44 @@ MAKE_REFLECT_STRUCT(Out_TextDocumentTypeDefinition, jsonrpc, id, result);
 struct TextDocumentTypeDefinitionHandler
     : BaseMessageHandler<Ipc_TextDocumentTypeDefinition> {
   void Run(Ipc_TextDocumentTypeDefinition* request) override {
+      QueryFile* file;
+      if (!FindFileOrFail(db, project, request->id,
+                          request->params.textDocument.uri.GetPath(), &file,
+                          nullptr)) {
+        return;
+      }
+      WorkingFile* working_file =
+          working_files->GetFileByFilename(file->def->path);
+
+      Out_TextDocumentTypeDefinition out;
+      out.id = request->id;
+      for (SymbolRef sym :
+             FindSymbolsAtLocation(working_file, file, request->params.position)) {
+        Id<void> id = sym.id;
+        switch (sym.kind) {
+        case SymbolKind::Var: {
+          const QueryVar::Def* def = db->GetVar(sym).AnyDef();
+          if (!def || !def->type)
+            continue;
+          id = *def->type;
+        }
+          // fallthrough
+        case SymbolKind::Type: {
+          QueryType& type = db->types[id.id];
+          for (const auto& def : type.def)
+            if (def.spell) {
+              if (auto ls_loc = GetLsLocationEx(db, working_files, *def.spell,
+                                                config->xref.container))
+                out.result.push_back(*ls_loc);
+            }
+          break;
+        }
+        default:
+          break;
+        }
+      }
+
+      QueueManager::WriteStdout(IpcId::TextDocumentTypeDefinition, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentTypeDefinitionHandler);