[clang-format] Fix a bug in annotating ClassHeadName (llvm#125326)

Author: owenca

clang/lib/Format/UnwrappedLineParser.cpp

@@ -4106,7 +4106,7 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
       if (AngleNestingLevel == 0) {
         if (FormatTok->is(tok::colon)) {
           IsDerived = true;
-        } else if (FormatTok->is(tok::identifier) &&
+        } else if (!IsDerived && FormatTok->is(tok::identifier) &&
                    FormatTok->Previous->is(tok::coloncolon)) {
           ClassName = FormatTok;
         } else if (FormatTok->is(tok::l_paren) &&

clang/unittests/Format/TokenAnnotatorTest.cpp

@@ -3406,6 +3406,13 @@ TEST_F(TokenAnnotatorTest, BraceKind) {
   EXPECT_BRACE_KIND(Tokens[7], BK_Block);
   EXPECT_BRACE_KIND(Tokens[8], BK_Block);
 
+  Tokens = annotate("struct Foo<int> : Base::Bar {};");
+  ASSERT_EQ(Tokens.size(), 13u) << Tokens;
+  EXPECT_TOKEN(Tokens[1], tok::identifier, TT_ClassHeadName);
+  EXPECT_TOKEN(Tokens[8], tok::identifier, TT_Unknown); // Not TT_ClassHeadName.
+  EXPECT_BRACE_KIND(Tokens[9], BK_Block);
+  EXPECT_BRACE_KIND(Tokens[10], BK_Block);
+
   Tokens = annotate("struct Foo final {};");
   ASSERT_EQ(Tokens.size(), 7u) << Tokens;
   EXPECT_TOKEN(Tokens[1], tok::identifier, TT_ClassHeadName);