[PATCH] D89098: [clang] Fix returning the underlying VarDecl as top-level decl for VarTemplateDecl.

[Haojian Wu via Phabricator via cfe-commits]

hokein created this revision.
hokein added a reviewer: sammccall.
Herald added subscribers: usaxena95, kadircet, arphaman, kristof.beyls.
Herald added a project: clang.
hokein requested review of this revision.

Given the following VarTemplateDecl AST,

  VarTemplateDecl col:26 X
  |-TemplateTypeParmDecl typename depth 0 index 0
  `-VarDecl X 'bool' cinit
    `-CXXBoolLiteralExpr 'bool' true

previously, we returned the VarDecl as the top-level decl, which was not
correct, the top-level decl should be VarTemplateDecl.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D89098

Files:
  clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
  clang/lib/Parse/ParseDecl.cpp


Index: clang/lib/Parse/ParseDecl.cpp
===================================================================
--- clang/lib/Parse/ParseDecl.cpp
+++ clang/lib/Parse/ParseDecl.cpp
@@ -2195,6 +2195,7 @@
 
   // Inform the current actions module that we just parsed this declarator.
   Decl *ThisDecl = nullptr;
+  VarTemplateDecl *VarTemplateD = nullptr;
   switch (TemplateInfo.Kind) {
   case ParsedTemplateInfo::NonTemplate:
     ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
@@ -2205,10 +2206,12 @@
     ThisDecl = Actions.ActOnTemplateDeclarator(getCurScope(),
                                                *TemplateInfo.TemplateParams,
                                                D);
-    if (VarTemplateDecl *VT = dyn_cast_or_null<VarTemplateDecl>(ThisDecl))
+    if (VarTemplateDecl *VT = dyn_cast_or_null<VarTemplateDecl>(ThisDecl)) {
       // Re-direct this decl to refer to the templated decl so that we can
       // initialize it.
       ThisDecl = VT->getTemplatedDecl();
+      VarTemplateD = VT;
+    }
     break;
   }
   case ParsedTemplateInfo::ExplicitInstantiation: {
@@ -2385,8 +2388,7 @@
   }
 
   Actions.FinalizeDeclaration(ThisDecl);
-
-  return ThisDecl;
+  return VarTemplateD ? VarTemplateD : ThisDecl;
 }
 
 /// ParseSpecifierQualifierList
Index: clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
===================================================================
--- clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
+++ clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
@@ -104,6 +104,14 @@
   EXPECT_THAT(AST.getLocalTopLevelDecls(), ElementsAre(DeclNamed("main")));
 }
 
+TEST(ParsedASTTest, VarTemplateDecl) {
+  TestTU TU;
+  TU.Code = "template <typename> bool X = true;";
+  auto AST = TU.build();
+  EXPECT_THAT(AST.getLocalTopLevelDecls(),
+              ElementsAre(AllOf(DeclNamed("X"), WithTemplateArgs(""))));
+}
+
 TEST(ParsedASTTest, DoesNotGetIncludedTopDecls) {
   TestTU TU;
   TU.HeaderCode = R"cpp(


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