[clang-tools-extra] 702529d - [clang] Fix returning the underlying VarDecl as top-level decl for VarTemplateDecl.

[Haojian Wu via cfe-commits]

Author: Haojian Wu
Date: 2020-10-12T10:46:18+02:00
New Revision: 702529d899c87e9268bb33d836dbc91b6bce0b16

URL: https://github.com/llvm/llvm-project/commit/702529d899c87e9268bb33d836dbc91b6bce0b16
DIFF: https://github.com/llvm/llvm-project/commit/702529d899c87e9268bb33d836dbc91b6bce0b16.diff

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

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.

Differential Revision: https://reviews.llvm.org/D89098

Added: 
    

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

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/clangd/unittests/ParsedASTTests.cpp b/clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
index 65d9cffeedc7..db23438766d2 100644
--- a/clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
+++ b/clang-tools-extra/clangd/unittests/ParsedASTTests.cpp
@@ -57,6 +57,12 @@ MATCHER_P(DeclNamed, Name, "") {
   return false;
 }
 
+MATCHER_P(DeclKind, Kind, "") {
+  if (NamedDecl *ND = dyn_cast<NamedDecl>(arg))
+    return ND->getDeclKindName() == Kind;
+  return false;
+}
+
 // Matches if the Decl has template args equal to ArgName. If the decl is a
 // NamedDecl and ArgName is an empty string it also matches.
 MATCHER_P(WithTemplateArgs, ArgName, "") {
@@ -99,9 +105,15 @@ TEST(ParsedASTTest, TopLevelDecls) {
     int header1();
     int header2;
   )";
-  TU.Code = "int main();";
+  TU.Code = R"cpp(
+    int main();
+    template <typename> bool X = true;
+  )cpp";
   auto AST = TU.build();
-  EXPECT_THAT(AST.getLocalTopLevelDecls(), ElementsAre(DeclNamed("main")));
+  EXPECT_THAT(
+      AST.getLocalTopLevelDecls(),
+      ElementsAreArray({AllOf(DeclNamed("main"), DeclKind("Function")),
+                        AllOf(DeclNamed("X"), DeclKind("VarTemplate"))}));
 }
 
 TEST(ParsedASTTest, DoesNotGetIncludedTopDecls) {

diff  --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 3f314c59ade6..01a16575c239 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2195,6 +2195,7 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
 
   // Inform the current actions module that we just parsed this declarator.
   Decl *ThisDecl = nullptr;
+  Decl *OuterDecl = nullptr;
   switch (TemplateInfo.Kind) {
   case ParsedTemplateInfo::NonTemplate:
     ThisDecl = Actions.ActOnDeclarator(getCurScope(), D);
@@ -2205,10 +2206,12 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
     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();
+      OuterDecl = VT;
+    }
     break;
   }
   case ParsedTemplateInfo::ExplicitInstantiation: {
@@ -2385,8 +2388,7 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
   }
 
   Actions.FinalizeDeclaration(ThisDecl);
-
-  return ThisDecl;
+  return OuterDecl ? OuterDecl : ThisDecl;
 }
 
 /// ParseSpecifierQualifierList