[clang-tidy] Avoid duplicated DenseMap lookup.

The std::string is still constructed on demand. No functionality change
intended.

llvm-svn: 276282

diff --git a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
index d0a7e5f..619c0c1 100644 (file)
--- a/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
+++ b/clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
@@ -176,8 +176,7 @@ DiagnosticBuilder ClangTidyContext::diag(
   assert(Loc.isValid());
   unsigned ID = DiagEngine->getDiagnosticIDs()->getCustomDiagID(
       Level, (Description + " [" + CheckName + "]").str());
-  if (CheckNamesByDiagnosticID.count(ID) == 0)
-    CheckNamesByDiagnosticID.insert(std::make_pair(ID, CheckName.str()));
+  CheckNamesByDiagnosticID.try_emplace(ID, CheckName);
   return DiagEngine->Report(Loc, ID);
 }