[clang-format] Add ClassHeadName to help annotating StartOfName (#124891)

Fixes #124574.

1 files changed, 10 insertions, 5 deletions

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 120922d..1411197 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -4029,7 +4029,7 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
   const FormatToken &InitialToken = *FormatTok;
   nextToken();
 
-  const FormatToken *ClassName = nullptr;
+  FormatToken *ClassName = nullptr;
   bool IsDerived = false;
   auto IsNonMacroIdentifier = [](const FormatToken *Tok) {
     return Tok->is(tok::identifier) && Tok->TokenText != Tok->TokenText.upper();
@@ -4059,7 +4059,7 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
     }
     if (FormatTok->is(tok::l_square) && handleCppAttributes())
       continue;
-    const auto *Previous = FormatTok;
+    auto *Previous = FormatTok;
     nextToken();
     switch (FormatTok->Tok.getKind()) {
     case tok::l_paren:
@@ -4074,9 +4074,12 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
     case tok::hashhash:
       break;
     default:
-      if (!JSPastExtendsOrImplements && !ClassName &&
-          Previous->is(tok::identifier) && Previous->isNot(TT_AttributeMacro) &&
-          Previous->TokenText != Previous->TokenText.upper()) {
+      if (JSPastExtendsOrImplements || ClassName ||
+          Previous->isNot(tok::identifier) || Previous->is(TT_AttributeMacro)) {
+        break;
+      }
+      if (const auto Text = Previous->TokenText;
+          Text.size() == 1 || Text != Text.upper()) {
         ClassName = Previous;
       }
     }
@@ -4160,6 +4163,8 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
   if (FormatTok->is(tok::l_brace)) {
     if (IsListInitialization())
       return;
+    if (ClassName)
+      ClassName->setFinalizedType(TT_ClassHeadName);
     auto [OpenBraceType, ClosingBraceType] = GetBraceTypes(InitialToken);
     FormatTok->setFinalizedType(OpenBraceType);
     if (ParseAsExpr) {