[clang] [clang-format] Treat uppercase identifiers after struct as macros (PR #124397)

[Owen Pan via cfe-commits]

https://github.com/owenca created https://github.com/llvm/llvm-project/pull/124397

This restores the behavior before llvmorg-20-init.

Fixes #94184.

>From e0567ce91a07df1b9a497adb63d5842441855d92 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Fri, 24 Jan 2025 22:47:26 -0800
Subject: [PATCH] [clang-format] Treat uppercase identifiers after struct as
 macros

This restores the behavior before llvmorg-20-init.

Fixes #94184.
---
 clang/lib/Format/UnwrappedLineParser.cpp      | 3 ++-
 clang/unittests/Format/TokenAnnotatorTest.cpp | 9 ++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 42583291363482..906fc11a07d5ee 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -4075,7 +4075,8 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
       break;
     default:
       if (!JSPastExtendsOrImplements && !ClassName &&
-          Previous->is(tok::identifier) && Previous->isNot(TT_AttributeMacro)) {
+          Previous->is(tok::identifier) && Previous->isNot(TT_AttributeMacro) &&
+          Previous->TokenText != Previous->TokenText.upper()) {
         ClassName = Previous;
       }
     }
diff --git a/clang/unittests/Format/TokenAnnotatorTest.cpp b/clang/unittests/Format/TokenAnnotatorTest.cpp
index 10587449dcea95..585878e0edc5bb 100644
--- a/clang/unittests/Format/TokenAnnotatorTest.cpp
+++ b/clang/unittests/Format/TokenAnnotatorTest.cpp
@@ -560,9 +560,16 @@ TEST_F(TokenAnnotatorTest, UnderstandsStructs) {
   ASSERT_EQ(Tokens.size(), 15u) << Tokens;
   EXPECT_TOKEN(Tokens[11], tok::l_brace, TT_StructLBrace);
 
+  constexpr StringRef Code{"struct EXPORT StructName {};"};
+
+  Tokens = annotate(Code);
+  ASSERT_EQ(Tokens.size(), 7u) << Tokens;
+  EXPECT_TOKEN(Tokens[3], tok::l_brace, TT_StructLBrace);
+  EXPECT_TOKEN(Tokens[4], tok::r_brace, TT_StructRBrace);
+
   auto Style = getLLVMStyle();
   Style.AttributeMacros.push_back("EXPORT");
-  Tokens = annotate("struct EXPORT StructName {};", Style);
+  Tokens = annotate(Code, Style);
   ASSERT_EQ(Tokens.size(), 7u) << Tokens;
   EXPECT_TOKEN(Tokens[1], tok::identifier, TT_AttributeMacro);
   EXPECT_TOKEN(Tokens[3], tok::l_brace, TT_StructLBrace);