[clang-format] Add SkipMacroDefinitionBody option

clang/docs/ClangFormatStyleOptions.rst

@@ -4999,6 +4999,11 @@ the configuration (without a prefix: ``Auto``).
        int bar;                           int bar;
      } // namespace b                   } // namespace b
 
+.. _SkipMacroDefinitionBody:
+
+**SkipMacroDefinitionBody** (``Boolean``) :versionbadge:`clang-format 18` :ref:`¶ <SkipMacroDefinitionBody>`
+  Do not format macro definition body.
+
 .. _SortIncludes:
 
 **SortIncludes** (``SortIncludesOptions``) :versionbadge:`clang-format 3.8` :ref:`¶ <SortIncludes>`

clang/docs/ReleaseNotes.rst

@@ -1202,6 +1202,7 @@ clang-format
 - Add ``PenaltyBreakScopeResolution`` option.
 - Add ``.clang-format-ignore`` files.
 - Add ``AlignFunctionPointers`` sub-option for ``AlignConsecutiveDeclarations``.
+- Add ``SkipMacroDefinitionBody`` option.
 
 libclang
 --------

clang/include/clang/Format/Format.h

@@ -3932,6 +3932,10 @@ struct FormatStyle {
   /// \version 13
   unsigned ShortNamespaceLines;
 
+  /// Do not format macro definition body.
+  /// \version 18
+  bool SkipMacroDefinitionBody;
+
   /// Include sorting options.
   enum SortIncludesOptions : int8_t {
     /// Includes are never sorted.
@@ -4895,6 +4899,7 @@ struct FormatStyle {
            RequiresExpressionIndentation == R.RequiresExpressionIndentation &&
            SeparateDefinitionBlocks == R.SeparateDefinitionBlocks &&
            ShortNamespaceLines == R.ShortNamespaceLines &&
+           SkipMacroDefinitionBody == R.SkipMacroDefinitionBody &&
            SortIncludes == R.SortIncludes &&
            SortJavaStaticImport == R.SortJavaStaticImport &&
            SpaceAfterCStyleCast == R.SpaceAfterCStyleCast &&

clang/lib/Format/Format.cpp

@@ -1085,6 +1085,7 @@ template <> struct MappingTraits<FormatStyle> {
                    Style.RequiresExpressionIndentation);
     IO.mapOptional("SeparateDefinitionBlocks", Style.SeparateDefinitionBlocks);
     IO.mapOptional("ShortNamespaceLines", Style.ShortNamespaceLines);
+    IO.mapOptional("SkipMacroDefinitionBody", Style.SkipMacroDefinitionBody);
     IO.mapOptional("SortIncludes", Style.SortIncludes);
     IO.mapOptional("SortJavaStaticImport", Style.SortJavaStaticImport);
     IO.mapOptional("SortUsingDeclarations", Style.SortUsingDeclarations);
@@ -1556,6 +1557,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.RequiresExpressionIndentation = FormatStyle::REI_OuterScope;
   LLVMStyle.SeparateDefinitionBlocks = FormatStyle::SDS_Leave;
   LLVMStyle.ShortNamespaceLines = 1;
+  LLVMStyle.SkipMacroDefinitionBody = false;
   LLVMStyle.SortIncludes = FormatStyle::SI_CaseSensitive;
   LLVMStyle.SortJavaStaticImport = FormatStyle::SJSIO_Before;
   LLVMStyle.SortUsingDeclarations = FormatStyle::SUD_LexicographicNumeric;

clang/lib/Format/UnwrappedLineParser.cpp

@@ -1170,6 +1170,15 @@ void UnwrappedLineParser::parsePPDefine() {
   assert((int)Line->PPLevel >= 0);
   Line->InMacroBody = true;
 
+  if (Style.SkipMacroDefinitionBody) {
+    do {
+      FormatTok->Finalized = true;
+      nextToken();
+    } while (!eof());
+    addUnwrappedLine();
+    return;
+  }
+
   if (FormatTok->is(tok::identifier) &&
       Tokens->peekNextToken()->is(tok::colon)) {
     nextToken();

clang/unittests/Format/ConfigParseTest.cpp

@@ -184,6 +184,7 @@ TEST(ConfigParseTest, ParsesConfigurationBools) {
   CHECK_PARSE_BOOL(ReflowComments);
   CHECK_PARSE_BOOL(RemoveBracesLLVM);
   CHECK_PARSE_BOOL(RemoveSemicolon);
+  CHECK_PARSE_BOOL(SkipMacroDefinitionBody);
   CHECK_PARSE_BOOL(SpacesInSquareBrackets);
   CHECK_PARSE_BOOL(SpaceInEmptyBlock);
   CHECK_PARSE_BOOL(SpacesInContainerLiterals);

clang/unittests/Format/FormatTest.cpp

@@ -24387,6 +24387,138 @@ TEST_F(FormatTest, WhitespaceSensitiveMacros) {
   verifyNoChange("FOO(String-ized&Messy+But: :Still=Intentional);", Style);
 }
 
+TEST_F(FormatTest, SkipMacroDefinitionBody) {
+  auto Style = getLLVMStyle();
+  Style.SkipMacroDefinitionBody = true;
+
+  verifyFormat("#define A", "#define  A", Style);
+  verifyFormat("#define A       a   aa", "#define   A       a   aa", Style);
+  verifyNoChange("#define A   b", Style);
+  verifyNoChange("#define A  (  args   )", Style);
+  verifyNoChange("#define A  (  args   )  =  func  (  args  )", Style);
+  verifyNoChange("#define A  (  args   )  {  int  a  =  1 ;  }", Style);
+  verifyNoChange("#define A  (  args   ) \\\n"
+                 "  {\\\n"
+                 "    int  a  =  1 ;\\\n"
+                 "}",
+                 Style);
+
+  verifyNoChange("#define A x:", Style);
+  verifyNoChange("#define A a. b", Style);
+
+  // Surrounded with formatted code.
+  verifyFormat("int a;\n"
+               "#define A  a\n"
+               "int a;",
+               "int  a ;\n"
+               "#define  A  a\n"
+               "int  a ;",
+               Style);
+
+  // Columns are not broken when a limit is set.
+  Style.ColumnLimit = 10;
+  verifyFormat("#define A  a  a  a  a", " # define  A  a  a  a  a ", Style);
+  verifyNoChange("#define A a a a a", Style);
+
+  Style.ColumnLimit = 15;
+  verifyFormat("#define A // a\n"
+               "          // very\n"
+               "          // long\n"
+               "          // comment",
+               "#define A //a very long comment", Style);
+  Style.ColumnLimit = 0;
+
+  // Multiline definition.
+  verifyNoChange("#define A \\\n"
+                 "Line one with spaces  .  \\\n"
+                 " Line two.",
+                 Style);
+  verifyNoChange("#define A \\\n"
+                 "a a \\\n"
+                 "a        \\\n"
+                 "a",
+                 Style);
+  Style.AlignEscapedNewlines = FormatStyle::ENAS_Left;
+  verifyNoChange("#define A \\\n"
+                 "a a \\\n"
+                 "a        \\\n"
+                 "a",
+                 Style);
+  Style.AlignEscapedNewlines = FormatStyle::ENAS_Right;
+  verifyNoChange("#define A \\\n"
+                 "a a \\\n"
+                 "a        \\\n"
+                 "a",
+                 Style);
+
+  // Adjust indendations but don't change the definition.
+  Style.IndentPPDirectives = FormatStyle::PPDIS_None;
+  verifyNoChange("#if A\n"
+                 "#define A  a\n"
+                 "#endif",
+                 Style);
+  verifyFormat("#if A\n"
+               "#define A  a\n"
+               "#endif",
+               "#if A\n"
+               "  #define A  a\n"
+               "#endif",
+               Style);
+  Style.IndentPPDirectives = FormatStyle::PPDIS_AfterHash;
+  verifyNoChange("#if A\n"
+                 "#  define A  a\n"
+                 "#endif",
+                 Style);
+  verifyFormat("#if A\n"
+               "#  define A  a\n"
+               "#endif",
+               "#if A\n"
+               "  #define A  a\n"
+               "#endif",
+               Style);
+  Style.IndentPPDirectives = FormatStyle::PPDIS_BeforeHash;
+  verifyNoChange("#if A\n"
+                 "  #define A  a\n"
+                 "#endif",
+                 Style);
+  verifyFormat("#if A\n"
+               "  #define A  a\n"
+               "#endif",
+               "#if A\n"
+               " # define A  a\n"
+               "#endif",
+               Style);
+
+  Style.IndentPPDirectives = FormatStyle::PPDIS_None;
+  // SkipMacroDefinitionBody should not affect other PP directives
+  verifyFormat("#if !defined(A)\n"
+               "#define A  a\n"
+               "#endif",
+               "#if ! defined ( A )\n"
+               "  #define  A  a\n"
+               "#endif",
+               Style);
+
+  // With comments.
+  verifyFormat("/* */ #define A  a //  a  a", "/* */  # define A  a  //  a  a",
+               Style);
+  verifyNoChange("/* */ #define A  a //  a  a", Style);
+
+  verifyFormat("int a;    // a\n"
+               "#define A // a\n"
+               "int aaa;  // a",
+               "int a; // a\n"
+               "#define A  // a\n"
+               "int aaa; // a",
+               Style);
+
+  // multiline macro definitions
+  verifyNoChange("#define A  a\\\n"
+                 "  A  a \\\n "
+                 " A  a",
+                 Style);
+}
+
 TEST_F(FormatTest, VeryLongNamespaceCommentSplit) {
   // These tests are not in NamespaceEndCommentsFixerTest because that doesn't
   // test its interaction with line wrapping