Add initialization option index.builtin_types for indexing builtin types

Also deprecate enableComments in favor of index.comments

Make $cquery/vars work on variables (by obtaining their types first).
This is currently the only way to list instances of builtin types.

src/clang_cursor.cc

@@ -119,18 +119,6 @@ CXCursorKind ClangCursor::get_kind() const {
   return cx_cursor.kind;
 }
 
-ClangCursor ClangCursor::get_declaration() const {
-  ClangType type = get_type();
-
-  // auto x = new Foo() will not be deduced to |Foo| if we do not use the
-  // canonical type. However, a canonical type will look past typedefs so we
-  // will not accurately report variables on typedefs if we always do this.
-  if (type.cx_type.kind == CXType_Auto)
-    type = type.get_canonical();
-
-  return type.strip_qualifiers().get_declaration();
-}
-
 ClangType ClangCursor::get_type() const {
   return ClangType(clang_getCursorType(cx_cursor));
 }

src/clang_cursor.h

@@ -51,7 +51,6 @@ class ClangCursor {
   bool operator!=(const ClangCursor& rhs) const;
 
   CXCursorKind get_kind() const;
-  ClangCursor get_declaration() const;
   ClangType get_type() const;
   std::string get_spelling() const;
   Range get_spelling_range(CXFile* cx_file = nullptr) const;

src/config.h

@@ -91,18 +91,27 @@ struct Config {
   // a function or method
   bool enableSnippetInsertion = true;
 
-  // 0: no; 1: Doxygen comment markers; 2: -fparse-all-comments, which includes
-  // plain // /*
+  // TODO Deprecated in favor of index.comments
   int enableComments = 0;
 
   // If true, filter and sort completion response.
   bool filterAndSortCompletionResponse = true;
 
+  struct Index {
+    bool builtin_types = false;
+
+    // 0: no; 1: Doxygen comment markers; 2: -fparse-all-comments, which includes
+    // plain // /*
+    int comments = 0;
+  };
+  Index index;
+
   //// For debugging
 
   // Dump AST after parsing if some pattern matches the source filename.
   std::vector<std::string> dumpAST;
 };
+MAKE_REFLECT_STRUCT(Config::Index, builtin_types, comments);
 MAKE_REFLECT_STRUCT(Config,
                     compilationDatabaseDirectory,
                     cacheDirectory,
@@ -141,6 +150,8 @@ MAKE_REFLECT_STRUCT(Config,
 
                     enableComments,
 
+                    index,
+
                     filterAndSortCompletionResponse,
 
                     dumpAST);

src/indexer.cc

@@ -17,6 +17,9 @@
 // TODO: See if we can use clang_indexLoc_getFileLocation to get a type ref on
 // |Foobar| in DISALLOW_COPY(Foobar)
 
+// TODO Global variable
+bool g_index_builtin_types;
+
 namespace {
 
 constexpr bool kIndexStdDeclarations = true;
@@ -393,13 +396,35 @@ bool IsFunctionCallContext(CXCursorKind kind) {
 // (ie, Foo<A,B> => Foo<*,*>).
 optional<IndexTypeId> ResolveToDeclarationType(IndexFile* db,
                                                ClangCursor cursor) {
-  ClangCursor declaration = cursor.get_declaration();
-  declaration = declaration.template_specialization_to_template_definition();
-  // TODO optimize
-  std::string usr = declaration.get_usr();
-  if (usr.size())
-    return db->ToTypeId(declaration.get_usr_hash());
-  return nullopt;
+  ClangType type = cursor.get_type();
+
+  // auto x = new Foo() will not be deduced to |Foo| if we do not use the
+  // canonical type. However, a canonical type will look past typedefs so we
+  // will not accurately report variables on typedefs if we always do this.
+  if (type.cx_type.kind == CXType_Auto)
+    type = type.get_canonical();
+
+  type = type.strip_qualifiers();
+
+  if (CXType_FirstBuiltin <= type.cx_type.kind &&
+      type.cx_type.kind <= CXType_LastBuiltin) {
+    if (!g_index_builtin_types)
+      return nullopt;
+    return db->ToTypeId(type.cx_type.kind);
+  }
+
+  ClangCursor declaration =
+      ClangCursor(type.get_declaration())
+          .template_specialization_to_template_definition();
+  CXString cx_usr = clang_getCursorUSR(declaration.cx_cursor);
+  const char* str_usr = clang_getCString(cx_usr);
+  if (!str_usr || str_usr[0] == '\0') {
+    clang_disposeString(cx_usr);
+    return nullopt;
+  }
+  Usr usr = HashUsr(str_usr);
+  clang_disposeString(cx_usr);
+  return db->ToTypeId(usr);
 }
 
 void SetVarDetail(IndexVar* var,

src/messages/cquery_vars.cc

@@ -25,11 +25,24 @@ struct CqueryVarsHandler : BaseMessageHandler<Ipc_CqueryVars> {
     out.id = request->id;
     for (const SymbolRef& ref :
          FindSymbolsAtLocation(working_file, file, request->params.position)) {
-      if (ref.idx.kind == SymbolKind::Type) {
-        QueryType& type = db->types[ref.idx.idx];
-        std::vector<QueryLocation> locations =
-            ToQueryLocation(db, type.instances);
-        out.result = GetLsLocations(db, working_files, locations);
+      size_t id = ref.idx.idx;
+      switch (ref.idx.kind) {
+        default:
+          break;
+        case SymbolKind::Var: {
+          QueryVar& var = db->vars[id];
+          if (!var.def || !var.def->variable_type)
+            continue;
+          id = var.def->variable_type->id;
+        }
+        // fallthrough
+        case SymbolKind::Type: {
+          QueryType& type = db->types[id];
+          std::vector<QueryLocation> locations =
+              ToQueryLocation(db, type.instances);
+          out.result = GetLsLocations(db, working_files, locations);
+          break;
+        }
       }
     }
     QueueManager::WriteStdout(IpcId::CqueryVars, out);

src/messages/initialize.cc

@@ -14,6 +14,7 @@
 
 // TODO Cleanup global variables
 extern std::string g_init_options;
+extern bool g_index_builtin_types;
 extern int g_enable_comments;
 
 namespace {
@@ -74,7 +75,9 @@ struct InitializeHandler : BaseMessageHandler<Ipc_InitializeRequest> {
           }
         }
       }
-      g_enable_comments = config->enableComments;
+      g_index_builtin_types = config->index.builtin_types;
+      // TODO Remove enableComments
+      g_enable_comments = std::max(config->enableComments, config->index.comments);
 
       // Check client version.
       if (config->clientVersion.has_value() &&