Migrate clangd away from -fno-delayed-template-parsing

Author: localspook

clang-tools-extra/clangd/CodeComplete.cpp

@@ -1393,10 +1393,6 @@ bool semaCodeComplete(std::unique_ptr<CodeCompleteConsumer> Consumer,
   FrontendOpts.SkipFunctionBodies = true;
   // Disable typo correction in Sema.
   CI->getLangOpts().SpellChecking = false;
-  // Code completion won't trigger in delayed template bodies.
-  // This is on-by-default in windows to allow parsing SDK headers; we're only
-  // disabling it for the main-file (not preamble).
-  CI->getLangOpts().DelayedTemplateParsing = false;
   // Setup code completion.
   FrontendOpts.CodeCompleteOpts = Options;
   FrontendOpts.CodeCompletionAt.FileName = std::string(Input.FileName);

clang-tools-extra/clangd/ParsedAST.cpp

@@ -431,10 +431,6 @@ ParsedAST::build(llvm::StringRef Filename, const ParseInputs &Inputs,
   const PrecompiledPreamble *PreamblePCH =
       Preamble ? &Preamble->Preamble : nullptr;
 
-  // This is on-by-default in windows to allow parsing SDK headers, but it
-  // breaks many features. Disable it for the main-file (not preamble).
-  CI->getLangOpts().DelayedTemplateParsing = false;
-
   std::vector<std::unique_ptr<FeatureModule::ASTListener>> ASTListeners;
   if (Inputs.FeatureModules) {
     for (auto &M : *Inputs.FeatureModules) {

clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp

@@ -3953,8 +3953,8 @@ TEST(CompletionTest, DelayedTemplateParsing) {
     template <typename T> int foo() { return xx^; }
   )cpp");
   auto TU = TestTU::withCode(Test.code());
-  // Even though delayed-template-parsing is on, we will disable it to provide
-  // completion in templates.
+  // We provide completion in templates even when delayed-template-parsing
+  // is on.
   TU.ExtraArgs.push_back("-fdelayed-template-parsing");
 
   EXPECT_THAT(completions(TU, Test.point()).Completions,

clang-tools-extra/clangd/unittests/ParsedASTTests.cpp

@@ -203,7 +203,7 @@ TEST(ParsedASTTest,
                         AllOf(declNamed("foo"), withTemplateArgs("<bool>"))}));
 }
 
-TEST(ParsedASTTest, IgnoresDelayedTemplateParsing) {
+TEST(ParsedASTTest, WorksEvenWithDelayedTemplateParsing) {
   auto TU = TestTU::withCode(R"cpp(
     template <typename T> void xxx() {
       int yyy = 0;

clang-tools-extra/clangd/unittests/RenameTests.cpp

@@ -1382,7 +1382,6 @@ TEST(RenameTest, Renameable) {
     SCOPED_TRACE(Case.Code);
     Annotations T(Case.Code);
     TestTU TU = TestTU::withCode(T.code());
-    TU.ExtraArgs.push_back("-fno-delayed-template-parsing");
     if (Case.IsHeaderFile) {
       // We open the .h file as the main file.
       TU.Filename = "test.h";

clang-tools-extra/clangd/unittests/XRefsTests.cpp

@@ -1418,9 +1418,6 @@ TEST(LocateSymbol, Ambiguous) {
     }
   )cpp");
   auto TU = TestTU::withCode(T.code());
-  // FIXME: Go-to-definition in a template requires disabling delayed template
-  // parsing.
-  TU.ExtraArgs.push_back("-fno-delayed-template-parsing");
   auto AST = TU.build();
   // Ordered assertions are deliberate: we expect a predictable order.
   EXPECT_THAT(locateSymbolAt(AST, T.point("1")), ElementsAre(sym("str")));

clang-tools-extra/unittests/clang-tidy/ClangTidyTest.h

@@ -104,7 +104,6 @@ runCheckOnCode(StringRef Code, std::vector<ClangTidyError> *Errors = nullptr,
 
   std::vector<std::string> Args(1, "clang-tidy");
   Args.push_back("-fsyntax-only");
-  Args.push_back("-fno-delayed-template-parsing");
   std::string extension(
       std::string(llvm::sys::path::extension(Filename.str())));
   if (extension == ".m" || extension == ".mm") {