[llvm-branch-commits] [clang] release/19.x: [clang-format] Correctly annotate braces in macro definitions (#123279) (PR #123439)

[via llvm-branch-commits]

https://github.com/llvmbot created https://github.com/llvm/llvm-project/pull/123439

Backport a7bca1861bfcd1490319115c1027166e27f4ae27

Requested by: @owenca

>From b81158025235d50f1eb227ded9f5638f039c59e2 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Fri, 17 Jan 2025 19:26:00 -0800
Subject: [PATCH] [clang-format] Correctly annotate braces in macro definitions
 (#123279)

Fixes #123179.

(cherry picked from commit a7bca1861bfcd1490319115c1027166e27f4ae27)
---
 clang/lib/Format/UnwrappedLineParser.cpp      |  6 +++---
 clang/unittests/Format/FormatTest.cpp         | 11 -----------
 clang/unittests/Format/TokenAnnotatorTest.cpp | 19 ++++++++++++++++---
 3 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index e3fb976ee1cc44..eb520870bb7708 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -505,14 +505,14 @@ void UnwrappedLineParser::calculateBraceTypes(bool ExpectClassBody) {
     auto *NextTok = Tokens->getNextNonComment();
 
     if (!Line->InMacroBody && !Style.isTableGen()) {
-      // Skip PPDirective lines and comments.
+      // Skip PPDirective lines (except macro definitions) and comments.
       while (NextTok->is(tok::hash)) {
         NextTok = Tokens->getNextToken();
-        if (NextTok->is(tok::pp_not_keyword))
+        if (NextTok->isOneOf(tok::pp_not_keyword, tok::pp_define))
           break;
         do {
           NextTok = Tokens->getNextToken();
-        } while (!NextTok->HasUnescapedNewline && NextTok->isNot(tok::eof));
+        } while (NextTok->NewlinesBefore == 0 && NextTok->isNot(tok::eof));
 
         while (NextTok->is(tok::comment))
           NextTok = Tokens->getNextToken();
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 7b2947acea4a2e..e3daac5a23359f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -5725,23 +5725,12 @@ TEST_F(FormatTest, HashInMacroDefinition) {
 
   verifyFormat("#define A void # ## #", getLLVMStyleWithColumns(22));
 
-#if 0
-  // FIXME: The correct format is:
   verifyFormat("{\n"
                "  {\n"
                "#define GEN_ID(_x) char *_x{#_x}\n"
                "    GEN_ID(one);\n"
                "  }\n"
                "}");
-#endif
-  verifyFormat("{\n"
-               "  {\n"
-               "#define GEN_ID(_x) \\\n"
-               "  char *_x { #_x }\n"
-               "    GEN_ID(one);\n"
-               "  }\n"
-               "}",
-               getGoogleStyle());
 }
 
 TEST_F(FormatTest, RespectWhitespaceInMacroDefinitions) {
diff --git a/clang/unittests/Format/TokenAnnotatorTest.cpp b/clang/unittests/Format/TokenAnnotatorTest.cpp
index 7d4ff3dfa32490..8f7f86d401edf0 100644
--- a/clang/unittests/Format/TokenAnnotatorTest.cpp
+++ b/clang/unittests/Format/TokenAnnotatorTest.cpp
@@ -3214,14 +3214,27 @@ TEST_F(TokenAnnotatorTest, BraceKind) {
   EXPECT_BRACE_KIND(Tokens[0], BK_Block);
   EXPECT_TOKEN(Tokens[1], tok::l_brace, TT_BlockLBrace);
   EXPECT_BRACE_KIND(Tokens[1], BK_Block);
-#if 0
-  // FIXME:
   EXPECT_BRACE_KIND(Tokens[11], BK_BracedInit);
   EXPECT_BRACE_KIND(Tokens[14], BK_BracedInit);
-#endif
   EXPECT_BRACE_KIND(Tokens[20], BK_Block);
   EXPECT_BRACE_KIND(Tokens[21], BK_Block);
 
+  Tokens = annotate("{\n"
+                    "#define FOO \\\n"
+                    "  { \\\n"
+                    "    case bar: { \\\n"
+                    "      break; \\\n"
+                    "    } \\\n"
+                    "  }\n"
+                    "}");
+  ASSERT_EQ(Tokens.size(), 15u) << Tokens;
+  EXPECT_TOKEN(Tokens[4], tok::l_brace, TT_BlockLBrace);
+  EXPECT_BRACE_KIND(Tokens[4], BK_Block);
+  EXPECT_TOKEN(Tokens[7], tok::colon, TT_CaseLabelColon);
+  EXPECT_BRACE_KIND(Tokens[8], BK_Block);
+  EXPECT_BRACE_KIND(Tokens[11], BK_Block);
+  EXPECT_BRACE_KIND(Tokens[12], BK_Block);
+
   Tokens = annotate("a = class extends goog.a {};",
                     getGoogleStyle(FormatStyle::LK_JavaScript));
   ASSERT_EQ(Tokens.size(), 11u) << Tokens;