https://github.com/arkq updated https://github.com/llvm/llvm-project/pull/224223
>From 014d510d55272f29ca0d3d825b93aea0365f3f99 Mon Sep 17 00:00:00 2001 From: Arkadiusz Bokowy <[email protected]> Date: Thu, 17 Sep 2026 09:47:42 +0200 Subject: [PATCH] [clang-format] Add KeepEmptyLines.AtEndOfBlock option Add support for the AtEndOfBlock option in KeepEmptyLines configuration, which controls whether empty lines are preserved before closing braces. This feature works in pair with AtStartOfBlock for control of empty lines at the beginning and end of blocks. The default is false, which should maintain backward compatibility by removing empty lines before closing braces. When set to true, empty lines before closing braces are preserved respecting MaxEmptyLinesToKeep limit. Closes #22073 and #171003 --- clang/docs/ClangFormatStyleOptions.md | 11 +++++ clang/include/clang/Format/Format.h | 13 +++++- clang/lib/Format/ContinuationIndenter.cpp | 6 ++- clang/lib/Format/Format.cpp | 2 + clang/lib/Format/UnwrappedLineFormatter.cpp | 3 +- clang/unittests/Format/ConfigParseTest.cpp | 1 + clang/unittests/Format/FormatTest.cpp | 47 +++++++++++++++++++++ 7 files changed, 79 insertions(+), 4 deletions(-) diff --git a/clang/docs/ClangFormatStyleOptions.md b/clang/docs/ClangFormatStyleOptions.md index 81984ff185e53..cd3c7b60391a0 100644 --- a/clang/docs/ClangFormatStyleOptions.md +++ b/clang/docs/ClangFormatStyleOptions.md @@ -5388,11 +5388,22 @@ the configuration (without a prefix: `Auto`). ```c++ KeepEmptyLines: + AtEndOfBlock: false AtEndOfFile: false AtStartOfBlock: false AtStartOfFile: false ``` + - `bool AtEndOfBlock` Keep empty lines at end of a block. + + ```c++ + true: false: + if (foo) { vs. if (foo) { + bar(); bar(); + } + } + ``` + - `bool AtEndOfFile` Keep empty lines at end of file. - `bool AtStartOfBlock` Keep empty lines at start of a block. diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h index baf56a9937957..a5b6e76d06b08 100644 --- a/clang/include/clang/Format/Format.h +++ b/clang/include/clang/Format/Format.h @@ -3750,11 +3750,21 @@ struct FormatStyle { /// /// \code /// KeepEmptyLines: + /// AtEndOfBlock: false /// AtEndOfFile: false /// AtStartOfBlock: false /// AtStartOfFile: false /// \endcode struct KeepEmptyLinesStyle { + /// Keep empty lines at end of a block. + /// \code + /// true: false: + /// if (foo) { vs. if (foo) { + /// bar(); bar(); + /// } + /// } + /// \endcode + bool AtEndOfBlock; /// Keep empty lines at end of file. bool AtEndOfFile; /// Keep empty lines at start of a block. @@ -3769,7 +3779,8 @@ struct FormatStyle { /// Keep empty lines at start of file. bool AtStartOfFile; bool operator==(const KeepEmptyLinesStyle &R) const { - return AtEndOfFile == R.AtEndOfFile && + return AtEndOfBlock == R.AtEndOfBlock && + AtEndOfFile == R.AtEndOfFile && AtStartOfBlock == R.AtStartOfBlock && AtStartOfFile == R.AtStartOfFile; } diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp index aa264c1487bce..97efbc2e6043a 100644 --- a/clang/lib/Format/ContinuationIndenter.cpp +++ b/clang/lib/Format/ContinuationIndenter.cpp @@ -1309,8 +1309,10 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State, !Current.MatchingParen->Children.empty()) { // lambdas and arrow functions are expressions, thus their r_brace is not // on its own line, and thus not covered by UnwrappedLineFormatter's logic - // about removing empty lines on closing blocks. Special case them here. - MaxEmptyLinesToKeep = 1; + // about removing empty lines on closing blocks. Special case them here + // with an exception if the KeepEmptyLines.AtEndOfBlock is used. + if (!Style.KeepEmptyLines.AtEndOfBlock) + MaxEmptyLinesToKeep = 1; } const unsigned Newlines = std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep)); diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp index 4c78c1dbe9f80..c49144f3291de 100644 --- a/clang/lib/Format/Format.cpp +++ b/clang/lib/Format/Format.cpp @@ -517,6 +517,7 @@ template <> struct ScalarEnumerationTraits<FormatStyle::JavaScriptQuoteStyle> { template <> struct MappingTraits<FormatStyle::KeepEmptyLinesStyle> { static void mapping(IO &IO, FormatStyle::KeepEmptyLinesStyle &Value) { + IO.mapOptional("AtEndOfBlock", Value.AtEndOfBlock); IO.mapOptional("AtEndOfFile", Value.AtEndOfFile); IO.mapOptional("AtStartOfBlock", Value.AtStartOfBlock); IO.mapOptional("AtStartOfFile", Value.AtStartOfFile); @@ -1993,6 +1994,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) { LLVMStyle.JavaScriptQuotes = FormatStyle::JSQS_Leave; LLVMStyle.JavaScriptWrapImports = true; LLVMStyle.KeepEmptyLines = { + /*AtEndOfBlock=*/false, /*AtEndOfFile=*/false, /*AtStartOfBlock=*/true, /*AtStartOfFile=*/true, diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp index f005f228328ce..41a8aa1f96f05 100644 --- a/clang/lib/Format/UnwrappedLineFormatter.cpp +++ b/clang/lib/Format/UnwrappedLineFormatter.cpp @@ -1657,7 +1657,8 @@ static auto computeNewlines(const AnnotatedLine &Line, (!RootToken.Next || (RootToken.Next->is(tok::semi) && !RootToken.Next->Next)) && // Do not remove empty lines before namespace closing "}". - !getNamespaceToken(&Line, Lines)) { + !getNamespaceToken(&Line, Lines) && + !Style.KeepEmptyLines.AtEndOfBlock) { Newlines = std::min(Newlines, 1u); } // Remove empty lines at the start of nested blocks (lambdas/arrow functions) diff --git a/clang/unittests/Format/ConfigParseTest.cpp b/clang/unittests/Format/ConfigParseTest.cpp index 86511edb9d40d..32839712e297a 100644 --- a/clang/unittests/Format/ConfigParseTest.cpp +++ b/clang/unittests/Format/ConfigParseTest.cpp @@ -254,6 +254,7 @@ TEST(ConfigParseTest, ParsesConfigurationBools) { CHECK_PARSE_NESTED_BOOL(BraceWrapping, SplitEmptyFunction); CHECK_PARSE_NESTED_BOOL(BraceWrapping, SplitEmptyRecord); CHECK_PARSE_NESTED_BOOL(BraceWrapping, SplitEmptyNamespace); + CHECK_PARSE_NESTED_BOOL(KeepEmptyLines, AtEndOfBlock); CHECK_PARSE_NESTED_BOOL(KeepEmptyLines, AtEndOfFile); CHECK_PARSE_NESTED_BOOL(KeepEmptyLines, AtStartOfBlock); CHECK_PARSE_NESTED_BOOL(KeepEmptyLines, AtStartOfFile); diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp index 5aed37aa56d52..f102c46a05972 100644 --- a/clang/unittests/Format/FormatTest.cpp +++ b/clang/unittests/Format/FormatTest.cpp @@ -170,6 +170,7 @@ TEST_F(FormatTest, RemovesEmptyLines) { CustomStyle.BreakBeforeBraces = FormatStyle::BS_Custom; CustomStyle.BraceWrapping.AfterNamespace = true; CustomStyle.KeepEmptyLines.AtStartOfBlock = false; + CustomStyle.KeepEmptyLines.AtEndOfBlock = false; verifyFormat("namespace N\n" "{\n" "\n" @@ -397,6 +398,7 @@ TEST_F(FormatTest, RemovesEmptyLines) { Style.BraceWrapping.AfterClass = true; Style.BraceWrapping.AfterFunction = true; Style.KeepEmptyLines.AtStartOfBlock = false; + Style.KeepEmptyLines.AtEndOfBlock = false; verifyFormat("class Foo\n" "{\n" @@ -25609,6 +25611,51 @@ TEST_F(FormatTest, KeepEmptyLinesAtEOF) { verifyFormat(Code, "int i;\n\n\n", Style); } +TEST_F(FormatTest, KeepEmptyLinesAtStartOfBlock) { + FormatStyle Style = getLLVMStyle(); + Style.AllowShortFunctionsOnASingleLine = + FormatStyle::ShortFunctionStyle::setEmptyAndInline(); + Style.KeepEmptyLines.AtStartOfBlock = true; + Style.MaxEmptyLinesToKeep = 2; + + verifyFormat("void foo() {\n" + "\n\n" + " int i;\n" + "}", + "void foo() {\n" + "\n\n\n\n" + " int i;\n" + "}", + Style); +} + +TEST_F(FormatTest, KeepEmptyLinesAtEndOfBlock) { + FormatStyle Style = getLLVMStyle(); + Style.AllowShortFunctionsOnASingleLine = + FormatStyle::ShortFunctionStyle::setEmptyAndInline(); + Style.KeepEmptyLines.AtEndOfBlock = true; + Style.MaxEmptyLinesToKeep = 2; + + verifyFormat("void foo() {\n" + " int i;\n" + "\n\n" + "}", + "void foo() {\n" + " int i;\n" + "\n\n\n\n" + "}", + Style); + verifyFormat("foo([]() {\n" + " int i;\n" + "\n\n" + "});", + "foo([]() {\n" + " int i;\n" + "\n\n\n\n" + "});", + Style); +} + TEST_F(FormatTest, SpaceAfterUDL) { verifyFormat("auto c = (4s).count();"); verifyFormat("auto x = 5s .count() == 5;"); _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
