https://github.com/frank-suwen created https://github.com/llvm/llvm-project/pull/204727
Adds a new `SpacesInComments` clang-format option to control spacing after `/*` and before `*/` in ordinary single-line block comments. Supported values: * Always: formats `/*comment*/` as `/* comment */` * Never: formats `/* comment */` as `/*comment*/` * Leave: preserves existing spacing Documentation comments such as `/** ... */` and `/*! ... */`, and parameter comments such as `/*Arg=*/`, are left unchanged. Tests added for all option values and for excluded parameter/doc comments. Fixes #160682. >From d2039b6757185d86f47e8185776eb332141fd887 Mon Sep 17 00:00:00 2001 From: frank-suwen <[email protected]> Date: Thu, 18 Jun 2026 21:49:51 -0700 Subject: [PATCH] [clang-format] Add SpacesInComments option for block comments --- clang/include/clang/Format/Format.h | 25 +++++++++++ clang/lib/Format/BreakableToken.cpp | 42 +++++++++++++++++++ clang/lib/Format/Format.cpp | 10 +++++ clang/unittests/Format/FormatTestComments.cpp | 34 +++++++++++++++ 4 files changed, 111 insertions(+) diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h index 27b2d8f4a405b..10b546506684d 100644 --- a/clang/include/clang/Format/Format.h +++ b/clang/include/clang/Format/Format.h @@ -5590,6 +5590,30 @@ struct FormatStyle { /// \version 3.4 SpacesInAnglesStyle SpacesInAngles; + /// Styles for controlling spacing after ``/*`` and before ``*/`` in block + /// comments. + enum SpacesInCommentsStyle : int8_t { + /// Remove spaces after ``/*`` and before ``*/``. + /// \code + /// /*comment*/ + /// \endcode + SICS_Never, + /// Add spaces after ``/*`` and before ``*/``. + /// \code + /// /* comment */ + /// \endcode + SICS_Always, + /// Leave existing spaces unchanged. + SICS_Leave + }; + + /// The SpacesInCommentsStyle to use for single-line ordinary block comments. + /// Documentation comments such as ``/** ... */`` and ``/*! ... */`` and + /// parameter comments ending with ``=`` before the closing ``*/`` are left + /// unchanged. + /// \version 23 + SpacesInCommentsStyle SpacesInComments; + /// If ``true``, spaces will be inserted around if/for/switch/while /// conditions. /// This option is **deprecated**. See ``InConditionalStatements`` of @@ -6241,6 +6265,7 @@ struct FormatStyle { SpaceInEmptyBraces == R.SpaceInEmptyBraces && SpacesBeforeTrailingComments == R.SpacesBeforeTrailingComments && SpacesInAngles == R.SpacesInAngles && + SpacesInComments == R.SpacesInComments && SpacesInContainerLiterals == R.SpacesInContainerLiterals && SpacesInLineCommentPrefix.Minimum == R.SpacesInLineCommentPrefix.Minimum && diff --git a/clang/lib/Format/BreakableToken.cpp b/clang/lib/Format/BreakableToken.cpp index 9571a64797a2d..aaca54a010f4a 100644 --- a/clang/lib/Format/BreakableToken.cpp +++ b/clang/lib/Format/BreakableToken.cpp @@ -778,6 +778,48 @@ void BreakableBlockComment::reflow(unsigned LineIndex, void BreakableBlockComment::adaptStartOfLine( unsigned LineIndex, WhitespaceManager &Whitespaces) const { if (LineIndex == 0) { + StringRef Text = tokenAt(LineIndex).TokenText; + if (Style.SpacesInComments != FormatStyle::SICS_Leave && + Lines.size() == 1 && Text.size() >= 4) { + const bool IsDocComment = + Text.starts_with("/**") || Text.starts_with("/*!"); + const bool IsParamComment = Text.drop_back(2).trim(Blanks).ends_with("="); + if (!IsDocComment && !IsParamComment) { + StringRef AfterOpening = Text.drop_front(2); + if (!AfterOpening.empty()) { + const bool HasSpace = isWhitespace(AfterOpening.front()); + if (Style.SpacesInComments == FormatStyle::SICS_Always && !HasSpace) { + Whitespaces.replaceWhitespaceInToken( + tokenAt(LineIndex), /*Offset=*/2, /*ReplaceChars=*/0, + /*PreviousPostfix=*/"", /*CurrentPrefix=*/"", InPPDirective, + /*Newlines=*/0, /*Spaces=*/1); + } else if (Style.SpacesInComments == FormatStyle::SICS_Never && + HasSpace) { + Whitespaces.replaceWhitespaceInToken( + tokenAt(LineIndex), /*Offset=*/2, /*ReplaceChars=*/1, + /*PreviousPostfix=*/"", /*CurrentPrefix=*/"", InPPDirective, + /*Newlines=*/0, /*Spaces=*/0); + } + } + + StringRef BeforeClosing = Text.drop_back(2); + if (!BeforeClosing.empty()) { + const bool HasSpace = isWhitespace(BeforeClosing.back()); + if (Style.SpacesInComments == FormatStyle::SICS_Always && !HasSpace) { + Whitespaces.replaceWhitespaceInToken( + tokenAt(LineIndex), Text.size() - 2, /*ReplaceChars=*/0, + /*PreviousPostfix=*/"", /*CurrentPrefix=*/"", InPPDirective, + /*Newlines=*/0, /*Spaces=*/1); + } else if (Style.SpacesInComments == FormatStyle::SICS_Never && + HasSpace) { + Whitespaces.replaceWhitespaceInToken( + tokenAt(LineIndex), Text.size() - 3, /*ReplaceChars=*/1, + /*PreviousPostfix=*/"", /*CurrentPrefix=*/"", InPPDirective, + /*Newlines=*/0, /*Spaces=*/0); + } + } + } + } if (DelimitersOnNewline) { // Since we're breaking at index 1 below, the break position and the // break length are the same. diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp index a29d62c99bb95..a8801f5b5de8e 100644 --- a/clang/lib/Format/Format.cpp +++ b/clang/lib/Format/Format.cpp @@ -962,6 +962,14 @@ template <> struct ScalarEnumerationTraits<FormatStyle::SpacesInAnglesStyle> { } }; +template <> struct ScalarEnumerationTraits<FormatStyle::SpacesInCommentsStyle> { + static void enumeration(IO &IO, FormatStyle::SpacesInCommentsStyle &Value) { + IO.enumCase(Value, "Never", FormatStyle::SICS_Never); + IO.enumCase(Value, "Always", FormatStyle::SICS_Always); + IO.enumCase(Value, "Leave", FormatStyle::SICS_Leave); + } +}; + template <> struct MappingTraits<FormatStyle::SpacesInLineComment> { static void mapping(IO &IO, FormatStyle::SpacesInLineComment &Space) { // Transform the maximum to signed, to parse "-1" correctly @@ -1495,6 +1503,7 @@ template <> struct MappingTraits<FormatStyle> { IO.mapOptional("SpacesBeforeTrailingComments", Style.SpacesBeforeTrailingComments); IO.mapOptional("SpacesInAngles", Style.SpacesInAngles); + IO.mapOptional("SpacesInComments", Style.SpacesInComments); IO.mapOptional("SpacesInContainerLiterals", Style.SpacesInContainerLiterals); IO.mapOptional("SpacesInLineCommentPrefix", @@ -2019,6 +2028,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) { LLVMStyle.SpaceInEmptyBraces = FormatStyle::SIEB_Never; LLVMStyle.SpacesBeforeTrailingComments = 1; LLVMStyle.SpacesInAngles = FormatStyle::SIAS_Never; + LLVMStyle.SpacesInComments = FormatStyle::SICS_Leave; LLVMStyle.SpacesInContainerLiterals = true; LLVMStyle.SpacesInLineCommentPrefix = { /*Minimum=*/1, /*Maximum=*/std::numeric_limits<unsigned>::max()}; diff --git a/clang/unittests/Format/FormatTestComments.cpp b/clang/unittests/Format/FormatTestComments.cpp index 707016096f7d2..6d10831124079 100644 --- a/clang/unittests/Format/FormatTestComments.cpp +++ b/clang/unittests/Format/FormatTestComments.cpp @@ -370,6 +370,40 @@ TEST_F(FormatTestComments, RemovesTrailingWhitespaceOfComments) { verifyFormat("// comment \\\n", "// comment \\\n \t \v \f "); } +TEST_F(FormatTestComments, SpacesInBlockComments) { + FormatStyle Style = getLLVMStyle(); + + Style.SpacesInComments = FormatStyle::SICS_Always; + verifyFormat("/* comment */", "/* comment*/", Style); + verifyFormat("/* comment */", "/*comment */", Style); + verifyFormat("/* comment */", "/*comment*/", Style); + + Style.SpacesInComments = FormatStyle::SICS_Leave; + verifyFormat("/*comment*/", Style); + verifyFormat("/* comment*/", Style); + verifyFormat("/*comment */", Style); + verifyFormat("/* comment */", Style); + + Style.SpacesInComments = FormatStyle::SICS_Never; + verifyFormat("/*comment*/", "/* comment */", Style); + verifyFormat("/*comment*/", "/* comment*/", Style); + verifyFormat("/*comment*/", "/*comment */", Style); +} + +TEST_F(FormatTestComments, SpacesInBlockCommentsIgnoreParamAndDocComments) { + FormatStyle Style = getLLVMStyle(); + + Style.SpacesInComments = FormatStyle::SICS_Always; + verifyFormat("foo(/*Arg=*/value);", Style); + verifyFormat("/**doc*/", Style); + verifyFormat("/*!doc*/", Style); + + Style.SpacesInComments = FormatStyle::SICS_Never; + verifyFormat("foo(/*Arg=*/value);", Style); + verifyFormat("/** doc */", Style); + verifyFormat("/*! doc */", Style); +} + TEST_F(FormatTestComments, UnderstandsBlockComments) { verifyFormat("f(/*noSpaceAfterParameterNamingComment=*/true);"); verifyFormat("void f() { g(/*aaa=*/x, /*bbb=*/!y, /*c=*/::c); }"); _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
