[clang][CodeComplete] Propogate printing policy to FunctionDecl

[kadircet]

Summary

Printing policy was not propogated to functiondecls when creating a
completion string which resulted in canonical template parameters like
foo<type-parameter-0-0>. This patch propogates printing policy to those as
well.

Fixes https://github.com/clangd/clangd/issues/76

[ilya-biryukov]

The patch contains only tests, are we missing the actual functional change?

[merge_guards_bot]

Unit tests: fail. 61795 tests passed, 1 failed and 781 were skipped.

failed: Clangd Unit Tests._/ClangdTests/SignatureHelpTest.PartialSpec

clang-tidy: unknown.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or applying this patch.

Build artifacts: diff.json, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

[kadircet]

• Upload the correct diff

[kadircet]

In D72715#1819879, @ilya-biryukov wrote:

The patch contains only tests, are we missing the actual functional change?

oopsy

[merge_guards_bot]

Unit tests: pass. 61796 tests passed, 0 failed and 781 were skipped.

clang-tidy: unknown.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or applying this patch.

Build artifacts: diff.json, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

[hokein]

@kuhnel, I think we should exclude from running clang-format on lint test files.

[kuhnel]

thx for the feedback, I created an issue for this: https://github.com/google/llvm-premerge-checks/issues/98

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

TEST(CompletionTest, DeprecatedResults) {
   )cpp";
 
   EXPECT_THAT(
       completions(Body + "int main() { TestClang^ }").Completions,
       UnorderedElementsAre(AllOf(Named("TestClangd"), Not(Deprecated())),
                            AllOf(Named("TestClangc"), Deprecated())));
 }
 
+TEST(SignatureHelpTest, PartialSpec) {
+  const auto Results = signatures(R"cpp(
+      template <typename T> struct Foo {};
+      template <typename T> struct Foo<T*> { Foo(T); };
+      Foo<int*> F(^);)cpp");
+  EXPECT_THAT(Results.signatures, Contains(Sig("Foo([[T]])")));
+  EXPECT_EQ(0, Results.activeParameter);
+}
+
 TEST(SignatureHelpTest, InsideArgument) {
   {
     const auto Results = signatures(R"cpp(
       void foo(int x);
       void foo(int x, int y);
       int main() { foo(1+^); }
     )cpp");
     EXPECT_THAT(Results.signatures,

clang/lib/Sema/SemaCodeComplete.cpp

 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
 #include <list>
 #include <map>
 #include <string>
 #include <vector>
 
 using namespace clang;
 using namespace sema;
 
CodeCompleteConsumer::OverloadCandidate::CreateSignatureString(
   }
 
   if (FDecl) {
     if (IncludeBriefComments) {
       if (auto RC = getParameterComment(S.getASTContext(), *this, CurrentArg))
         Result.addBriefComment(RC->getBriefText(S.getASTContext()));
     }
     AddResultTypeChunk(S.Context, Policy, FDecl, QualType(), Result);
-    Result.AddTextChunk(
-        Result.getAllocator().CopyString(FDecl->getNameAsString()));
+
+    std::string Name;
+    llvm::raw_string_ostream OS(Name);
+    FDecl->getDeclName().print(OS, Policy);
+    Result.AddTextChunk(Result.getAllocator().CopyString(OS.str()));
   } else {
     Result.AddResultTypeChunk(Result.getAllocator().CopyString(
         Proto->getReturnType().getAsString(Policy)));
   }
 
   Result.AddChunk(CodeCompletionString::CK_LeftParen);
   AddOverloadParameterChunks(S.getASTContext(), Policy, FDecl, Proto, Result,
                              CurrentArg);

clang/test/CodeCompletion/ctor-signature.cpp

+template <typename T>
+struct Foo {};
+template <typename T>
+struct Foo<T *> { Foo(T); };
+
+void foo() {
+  Foo<int>();
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-at=%s:7:12 %s -o - | FileCheck -check-prefix=CHECK-CC1 %s
+  // CHECK-CC1: OVERLOAD: Foo()
+  // CHECK-CC1: OVERLOAD: Foo(<#const Foo<int> &#>)
+  // CHECK-CC1: OVERLOAD: Foo(<#Foo<int> &&#>
+  Foo<int *>(3);
+  // RUN: %clang_cc1 -fsyntax-only -code-completion-at=%s:12:14 %s -o - | FileCheck -check-prefix=CHECK-CC2 %s
+  // CHECK-CC2: OVERLOAD: Foo(<#int#>)
+  // CHECK-CC2: OVERLOAD: Foo(<#const Foo<int *> &#>)
+  // CHECK-CC2: OVERLOAD: Foo(<#Foo<int *> &&#>
+}