From: Francois Ferrand Date: Wed, 16 May 2018 08:25:03 +0000 (+0000) Subject: clang-format: Allow optimizer to break template declaration. X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5a506038868f5e5cb910927489de4a5c09e3d31d;p=clang clang-format: Allow optimizer to break template declaration. Summary: Introduce `PenaltyBreakTemplateDeclaration` to control the penalty, and change `AlwaysBreakTemplateDeclarations` to an enum with 3 modes: * `No` for regular, penalty based, wrapping of template declaration * `MultiLine` for always wrapping before multi-line declarations (e.g. same as legacy behavior when `AlwaysBreakTemplateDeclarations=false`) * `Yes` for always wrapping (e.g. same as legacy behavior when `AlwaysBreakTemplateDeclarations=true`) Reviewers: krasimir, djasper, klimek Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D42684 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@332436 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/docs/ClangFormatStyleOptions.rst b/docs/ClangFormatStyleOptions.rst index 816b39f06f..487660a6ee 100644 --- a/docs/ClangFormatStyleOptions.rst +++ b/docs/ClangFormatStyleOptions.rst @@ -490,15 +490,50 @@ the configuration (without a prefix: ``Auto``). "bbbb" "cccc"; "cccc"; -**AlwaysBreakTemplateDeclarations** (``bool``) - If ``true``, always break after the ``template<...>`` of a template - declaration. +**AlwaysBreakTemplateDeclarations** (``BreakTemplateDeclarationsStyle``) + The template declaration breaking style to use. + + Possible values: + + * ``BTDS_No`` (in configuration: ``No``) + Do not force break before declaration. + ``PenaltyBreakTemplateDeclaration`` is taken into account. + + .. code-block:: c++ + + template T foo() { + } + template T foo(int aaaaaaaaaaaaaaaaaaaaa, + int bbbbbbbbbbbbbbbbbbbbb) { + } + + * ``BTDS_MultiLine`` (in configuration: ``MultiLine``) + Force break after template declaration only when the following + declaration spans multiple lines. + + .. code-block:: c++ + + template T foo() { + } + template + T foo(int aaaaaaaaaaaaaaaaaaaaa, + int bbbbbbbbbbbbbbbbbbbbb) { + } + + * ``BTDS_Yes`` (in configuration: ``Yes``) + Always break after template declaration. + + .. code-block:: c++ + + template + T foo() { + } + template + T foo(int aaaaaaaaaaaaaaaaaaaaa, + int bbbbbbbbbbbbbbbbbbbbb) { + } - .. code-block:: c++ - true: false: - template vs. template class C {}; - class C {}; **BinPackArguments** (``bool``) If ``false``, a function call's arguments will either be all on the @@ -1590,6 +1625,9 @@ the configuration (without a prefix: ``Auto``). **PenaltyBreakString** (``unsigned``) The penalty for each line break introduced inside a string literal. +**PenaltyBreakTemplateDeclaration** (``unsigned``) + The penalty for breaking after template declaration. + **PenaltyExcessCharacter** (``unsigned``) The penalty for each character outside of the column limit. diff --git a/include/clang/Format/Format.h b/include/clang/Format/Format.h index 9b42cccf61..b4d99f0754 100644 --- a/include/clang/Format/Format.h +++ b/include/clang/Format/Format.h @@ -351,14 +351,44 @@ struct FormatStyle { /// \endcode bool AlwaysBreakBeforeMultilineStrings; - /// If ``true``, always break after the ``template<...>`` of a template - /// declaration. - /// \code - /// true: false: - /// template vs. template class C {}; - /// class C {}; - /// \endcode - bool AlwaysBreakTemplateDeclarations; + /// Different ways to break after the template declaration. + enum BreakTemplateDeclarationsStyle { + /// Do not force break before declaration. + /// ``PenaltyBreakTemplateDeclaration`` is taken into account. + /// \code + /// template T foo() { + /// } + /// template T foo(int aaaaaaaaaaaaaaaaaaaaa, + /// int bbbbbbbbbbbbbbbbbbbbb) { + /// } + /// \endcode + BTDS_No, + /// Force break after template declaration only when the following + /// declaration spans multiple lines. + /// \code + /// template T foo() { + /// } + /// template + /// T foo(int aaaaaaaaaaaaaaaaaaaaa, + /// int bbbbbbbbbbbbbbbbbbbbb) { + /// } + /// \endcode + BTDS_MultiLine, + /// Always break after template declaration. + /// \code + /// template + /// T foo() { + /// } + /// template + /// T foo(int aaaaaaaaaaaaaaaaaaaaa, + /// int bbbbbbbbbbbbbbbbbbbbb) { + /// } + /// \endcode + BTDS_Yes + }; + + /// The template declaration breaking style to use. + BreakTemplateDeclarationsStyle AlwaysBreakTemplateDeclarations; /// If ``false``, a function call's arguments will either be all on the /// same line or will have one line each. @@ -1295,6 +1325,9 @@ struct FormatStyle { /// The penalty for each line break introduced inside a string literal. unsigned PenaltyBreakString; + /// The penalty for breaking after template declaration. + unsigned PenaltyBreakTemplateDeclaration; + /// The penalty for each character outside of the column limit. unsigned PenaltyExcessCharacter; @@ -1679,6 +1712,8 @@ struct FormatStyle { PenaltyBreakString == R.PenaltyBreakString && PenaltyExcessCharacter == R.PenaltyExcessCharacter && PenaltyReturnTypeOnItsOwnLine == R.PenaltyReturnTypeOnItsOwnLine && + PenaltyBreakTemplateDeclaration == + R.PenaltyBreakTemplateDeclaration && PointerAlignment == R.PointerAlignment && RawStringFormats == R.RawStringFormats && SpaceAfterCStyleCast == R.SpaceAfterCStyleCast && diff --git a/lib/Format/ContinuationIndenter.cpp b/lib/Format/ContinuationIndenter.cpp index 20eb5c03b8..9a07c5ed59 100644 --- a/lib/Format/ContinuationIndenter.cpp +++ b/lib/Format/ContinuationIndenter.cpp @@ -402,6 +402,12 @@ bool ContinuationIndenter::mustBreak(const LineState &State) { Style.Language == FormatStyle::LK_JavaScript)) return true; + // If the template declaration spans multiple lines, force wrap before the + // function/class declaration + if (Previous.ClosesTemplateDeclaration && + State.Stack.back().BreakBeforeParameter) + return true; + if (State.Column <= NewLineColumn) return false; @@ -453,7 +459,7 @@ bool ContinuationIndenter::mustBreak(const LineState &State) { // for cases where the entire line does not fit on a single line as a // different LineFormatter would be used otherwise. if (Previous.ClosesTemplateDeclaration) - return true; + return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No; if (Previous.is(TT_FunctionAnnotationRParen)) return true; if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) && diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp index f3681a715e..c6de92b3ca 100644 --- a/lib/Format/Format.cpp +++ b/lib/Format/Format.cpp @@ -168,6 +168,19 @@ struct ScalarEnumerationTraits { } }; +template <> +struct ScalarEnumerationTraits { + static void enumeration(IO &IO, FormatStyle::BreakTemplateDeclarationsStyle &Value) { + IO.enumCase(Value, "No", FormatStyle::BTDS_No); + IO.enumCase(Value, "MultiLine", FormatStyle::BTDS_MultiLine); + IO.enumCase(Value, "Yes", FormatStyle::BTDS_Yes); + + // For backward compatibility. + IO.enumCase(Value, "false", FormatStyle::BTDS_MultiLine); + IO.enumCase(Value, "true", FormatStyle::BTDS_Yes); + } +}; + template <> struct ScalarEnumerationTraits { static void @@ -400,6 +413,8 @@ template <> struct MappingTraits { IO.mapOptional("PenaltyBreakFirstLessLess", Style.PenaltyBreakFirstLessLess); IO.mapOptional("PenaltyBreakString", Style.PenaltyBreakString); + IO.mapOptional("PenaltyBreakTemplateDeclaration", + Style.PenaltyBreakTemplateDeclaration); IO.mapOptional("PenaltyExcessCharacter", Style.PenaltyExcessCharacter); IO.mapOptional("PenaltyReturnTypeOnItsOwnLine", Style.PenaltyReturnTypeOnItsOwnLine); @@ -598,7 +613,7 @@ FormatStyle getLLVMStyle() { LLVMStyle.AlwaysBreakAfterReturnType = FormatStyle::RTBS_None; LLVMStyle.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_None; LLVMStyle.AlwaysBreakBeforeMultilineStrings = false; - LLVMStyle.AlwaysBreakTemplateDeclarations = false; + LLVMStyle.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_MultiLine; LLVMStyle.BinPackArguments = true; LLVMStyle.BinPackParameters = true; LLVMStyle.BreakBeforeBinaryOperators = FormatStyle::BOS_None; @@ -670,6 +685,7 @@ FormatStyle getLLVMStyle() { LLVMStyle.PenaltyExcessCharacter = 1000000; LLVMStyle.PenaltyReturnTypeOnItsOwnLine = 60; LLVMStyle.PenaltyBreakBeforeFirstCallParameter = 19; + LLVMStyle.PenaltyBreakTemplateDeclaration = prec::Relational; LLVMStyle.DisableFormat = false; LLVMStyle.SortIncludes = true; @@ -694,7 +710,7 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) { GoogleStyle.AllowShortIfStatementsOnASingleLine = true; GoogleStyle.AllowShortLoopsOnASingleLine = true; GoogleStyle.AlwaysBreakBeforeMultilineStrings = true; - GoogleStyle.AlwaysBreakTemplateDeclarations = true; + GoogleStyle.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_Yes; GoogleStyle.ConstructorInitializerAllOnOneLineOrOnePerLine = true; GoogleStyle.DerivePointerAlignment = true; GoogleStyle.IncludeStyle.IncludeCategories = { @@ -819,7 +835,7 @@ FormatStyle getMozillaStyle() { MozillaStyle.AlwaysBreakAfterReturnType = FormatStyle::RTBS_TopLevel; MozillaStyle.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_TopLevel; - MozillaStyle.AlwaysBreakTemplateDeclarations = true; + MozillaStyle.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_Yes; MozillaStyle.BinPackParameters = false; MozillaStyle.BinPackArguments = false; MozillaStyle.BreakBeforeBraces = FormatStyle::BS_Mozilla; diff --git a/lib/Format/TokenAnnotator.cpp b/lib/Format/TokenAnnotator.cpp index 61773e5b4a..5f13d103a6 100644 --- a/lib/Format/TokenAnnotator.cpp +++ b/lib/Format/TokenAnnotator.cpp @@ -2338,6 +2338,8 @@ unsigned TokenAnnotator::splitPenalty(const AnnotatedLine &Line, return 2; return 1; } + if (Left.ClosesTemplateDeclaration) + return Style.PenaltyBreakTemplateDeclaration; if (Left.is(TT_ConditionalExpr)) return prec::Conditional; prec::Level Level = Left.getPrecedence(); @@ -2869,7 +2871,7 @@ bool TokenAnnotator::mustBreakBefore(const AnnotatedLine &Line, if (Right.Previous->ClosesTemplateDeclaration && Right.Previous->MatchingParen && Right.Previous->MatchingParen->NestingLevel == 0 && - Style.AlwaysBreakTemplateDeclarations) + Style.AlwaysBreakTemplateDeclarations == FormatStyle::BTDS_Yes) return true; if (Right.is(TT_CtorInitializerComma) && Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma && diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp index 2b61a96a21..3f9e805631 100644 --- a/unittests/Format/FormatTest.cpp +++ b/unittests/Format/FormatTest.cpp @@ -5475,7 +5475,7 @@ TEST_F(FormatTest, WrapsTemplateDeclarations) { " const typename aaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaa);"); FormatStyle AlwaysBreak = getLLVMStyle(); - AlwaysBreak.AlwaysBreakTemplateDeclarations = true; + AlwaysBreak.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_Yes; verifyFormat("template \nclass C {};", AlwaysBreak); verifyFormat("template \nvoid f();", AlwaysBreak); verifyFormat("template \nvoid f() {}", AlwaysBreak); @@ -5493,6 +5493,32 @@ TEST_F(FormatTest, WrapsTemplateDeclarations) { "public:\n" " E *f();\n" "};"); + + FormatStyle NeverBreak = getLLVMStyle(); + NeverBreak.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_No; + verifyFormat("template class C {};", NeverBreak); + verifyFormat("template void f();", NeverBreak); + verifyFormat("template void f() {}", NeverBreak); + verifyFormat("template \nvoid foo(aaaaaaaaaaaaaaaaaaaaaaaaaa bbbbbbbbbbbbbbbbbbbb) {}", + NeverBreak); + verifyFormat("void aaaaaaaaaaaaaaaaaaa(\n" + " ccccccccccccccccccccccccccccccccccccccccccccccc);", + NeverBreak); + verifyFormat("template