//===--- ContinuationIndenter.cpp - Format C++ code -----------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// /// /// \file /// This file implements the continuation indenter. /// //===----------------------------------------------------------------------===// #include "ContinuationIndenter.h" #include "BreakableToken.h" #include "FormatInternal.h" #include "WhitespaceManager.h" #include "clang/Basic/OperatorPrecedence.h" #include "clang/Basic/SourceManager.h" #include "clang/Format/Format.h" #include "llvm/Support/Debug.h" #define DEBUG_TYPE "format-indenter" namespace clang { namespace format { // Returns true if a TT_SelectorName should be indented when wrapped, // false otherwise. static bool shouldIndentWrappedSelectorName(const FormatStyle &Style, LineType LineType) { return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl; } // Returns the length of everything up to the first possible line break after // the ), ], } or > matching \c Tok. static unsigned getLengthToMatchingParen(const FormatToken &Tok, const std::vector &Stack) { // Normally whether or not a break before T is possible is calculated and // stored in T.CanBreakBefore. Braces, array initializers and text proto // messages like `key: < ... >` are an exception: a break is possible // before a closing brace R if a break was inserted after the corresponding // opening brace. The information about whether or not a break is needed // before a closing brace R is stored in the ParenState field // S.BreakBeforeClosingBrace where S is the state that R closes. // // In order to decide whether there can be a break before encountered right // braces, this implementation iterates over the sequence of tokens and over // the paren stack in lockstep, keeping track of the stack level which visited // right braces correspond to in MatchingStackIndex. // // For example, consider: // L. <- line number // 1. { // 2. {1}, // 3. {2}, // 4. {{3}}} // ^ where we call this method with this token. // The paren stack at this point contains 3 brace levels: // 0. { at line 1, BreakBeforeClosingBrace: true // 1. first { at line 4, BreakBeforeClosingBrace: false // 2. second { at line 4, BreakBeforeClosingBrace: false, // where there might be fake parens levels in-between these levels. // The algorithm will start at the first } on line 4, which is the matching // brace of the initial left brace and at level 2 of the stack. Then, // examining BreakBeforeClosingBrace: false at level 2, it will continue to // the second } on line 4, and will traverse the stack downwards until it // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace: // false at level 1, it will continue to the third } on line 4 and will // traverse the stack downwards until it finds the matching { on level 0. // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm // will stop and will use the second } on line 4 to determine the length to // return, as in this example the range will include the tokens: {3}} // // The algorithm will only traverse the stack if it encounters braces, array // initializer squares or text proto angle brackets. if (!Tok.MatchingParen) return 0; FormatToken *End = Tok.MatchingParen; // Maintains a stack level corresponding to the current End token. int MatchingStackIndex = Stack.size() - 1; // Traverses the stack downwards, looking for the level to which LBrace // corresponds. Returns either a pointer to the matching level or nullptr if // LParen is not found in the initial portion of the stack up to // MatchingStackIndex. auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * { while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace) --MatchingStackIndex; return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr; }; for (; End->Next; End = End->Next) { if (End->Next->CanBreakBefore) break; if (!End->Next->closesScope()) continue; if (End->Next->MatchingParen && End->Next->MatchingParen->isOneOf( tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) { const ParenState *State = FindParenState(End->Next->MatchingParen); if (State && State->BreakBeforeClosingBrace) break; } } return End->TotalLength - Tok.TotalLength + 1; } static unsigned getLengthToNextOperator(const FormatToken &Tok) { if (!Tok.NextOperator) return 0; return Tok.NextOperator->TotalLength - Tok.TotalLength; } // Returns \c true if \c Tok is the "." or "->" of a call and starts the next // segment of a builder type call. static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) { return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope(); } // Returns \c true if \c Current starts a new parameter. static bool startsNextParameter(const FormatToken &Current, const FormatStyle &Style) { const FormatToken &Previous = *Current.Previous; if (Current.is(TT_CtorInitializerComma) && Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma) return true; if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName)) return true; return Previous.is(tok::comma) && !Current.isTrailingComment() && ((Previous.isNot(TT_CtorInitializerComma) || Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeComma) && (Previous.isNot(TT_InheritanceComma) || Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma)); } static bool opensProtoMessageField(const FormatToken &LessTok, const FormatStyle &Style) { if (LessTok.isNot(tok::less)) return false; return Style.Language == FormatStyle::LK_TextProto || (Style.Language == FormatStyle::LK_Proto && (LessTok.NestingLevel > 0 || (LessTok.Previous && LessTok.Previous->is(tok::equal)))); } // Returns the delimiter of a raw string literal, or None if TokenText is not // the text of a raw string literal. The delimiter could be the empty string. // For example, the delimiter of R"deli(cont)deli" is deli. static llvm::Optional getRawStringDelimiter(StringRef TokenText) { if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'. || !TokenText.startswith("R\"") || !TokenText.endswith("\"")) return None; // A raw string starts with 'R"(' and delimiter is ascii and has // size at most 16 by the standard, so the first '(' must be among the first // 19 bytes. size_t LParenPos = TokenText.substr(0, 19).find_first_of('('); if (LParenPos == StringRef::npos) return None; StringRef Delimiter = TokenText.substr(2, LParenPos - 2); // Check that the string ends in ')Delimiter"'. size_t RParenPos = TokenText.size() - Delimiter.size() - 2; if (TokenText[RParenPos] != ')') return None; if (!TokenText.substr(RParenPos + 1).startswith(Delimiter)) return None; return Delimiter; } // Returns the canonical delimiter for \p Language, or the empty string if no // canonical delimiter is specified. static StringRef getCanonicalRawStringDelimiter(const FormatStyle &Style, FormatStyle::LanguageKind Language) { for (const auto &Format : Style.RawStringFormats) { if (Format.Language == Language) return StringRef(Format.CanonicalDelimiter); } return ""; } RawStringFormatStyleManager::RawStringFormatStyleManager( const FormatStyle &CodeStyle) { for (const auto &RawStringFormat : CodeStyle.RawStringFormats) { llvm::Optional LanguageStyle = CodeStyle.GetLanguageStyle(RawStringFormat.Language); if (!LanguageStyle) { FormatStyle PredefinedStyle; if (!getPredefinedStyle(RawStringFormat.BasedOnStyle, RawStringFormat.Language, &PredefinedStyle)) { PredefinedStyle = getLLVMStyle(); PredefinedStyle.Language = RawStringFormat.Language; } LanguageStyle = PredefinedStyle; } LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit; for (StringRef Delimiter : RawStringFormat.Delimiters) { DelimiterStyle.insert({Delimiter, *LanguageStyle}); } for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions) { EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle}); } } } llvm::Optional RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const { auto It = DelimiterStyle.find(Delimiter); if (It == DelimiterStyle.end()) return None; return It->second; } llvm::Optional RawStringFormatStyleManager::getEnclosingFunctionStyle( StringRef EnclosingFunction) const { auto It = EnclosingFunctionStyle.find(EnclosingFunction); if (It == EnclosingFunctionStyle.end()) return None; return It->second; } ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style, const AdditionalKeywords &Keywords, const SourceManager &SourceMgr, WhitespaceManager &Whitespaces, encoding::Encoding Encoding, bool BinPackInconclusiveFunctions) : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr), Whitespaces(Whitespaces), Encoding(Encoding), BinPackInconclusiveFunctions(BinPackInconclusiveFunctions), CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {} LineState ContinuationIndenter::getInitialState(unsigned FirstIndent, unsigned FirstStartColumn, const AnnotatedLine *Line, bool DryRun) { LineState State; State.FirstIndent = FirstIndent; if (FirstStartColumn && Line->First->NewlinesBefore == 0) State.Column = FirstStartColumn; else State.Column = FirstIndent; // With preprocessor directive indentation, the line starts on column 0 // since it's indented after the hash, but FirstIndent is set to the // preprocessor indent. if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash && (Line->Type == LT_PreprocessorDirective || Line->Type == LT_ImportStatement)) State.Column = 0; State.Line = Line; State.NextToken = Line->First; State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent, /*AvoidBinPacking=*/false, /*NoLineBreak=*/false)); State.LineContainsContinuedForLoopSection = false; State.NoContinuation = false; State.StartOfStringLiteral = 0; State.StartOfLineLevel = 0; State.LowestLevelOnLine = 0; State.IgnoreStackForComparison = false; if (Style.Language == FormatStyle::LK_TextProto) { // We need this in order to deal with the bin packing of text fields at // global scope. State.Stack.back().AvoidBinPacking = true; State.Stack.back().BreakBeforeParameter = true; State.Stack.back().AlignColons = false; } // The first token has already been indented and thus consumed. moveStateToNextToken(State, DryRun, /*Newline=*/false); return State; } bool ContinuationIndenter::canBreak(const LineState &State) { const FormatToken &Current = *State.NextToken; const FormatToken &Previous = *Current.Previous; assert(&Previous == Current.Previous); if (!Current.CanBreakBefore && !(State.Stack.back().BreakBeforeClosingBrace && Current.closesBlockOrBlockTypeList(Style))) return false; // The opening "{" of a braced list has to be on the same line as the first // element if it is nested in another braced init list or function call. if (!Current.MustBreakBefore && Previous.is(tok::l_brace) && Previous.isNot(TT_DictLiteral) && Previous.BlockKind == BK_BracedInit && Previous.Previous && Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma)) return false; // This prevents breaks like: // ... // SomeParameter, OtherParameter).DoSomething( // ... // As they hide "DoSomething" and are generally bad for readability. if (Previous.opensScope() && Previous.isNot(tok::l_brace) && State.LowestLevelOnLine < State.StartOfLineLevel && State.LowestLevelOnLine < Current.NestingLevel) return false; if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder) return false; // Don't create a 'hanging' indent if there are multiple blocks in a single // statement. if (Previous.is(tok::l_brace) && State.Stack.size() > 1 && State.Stack[State.Stack.size() - 2].NestedBlockInlined && State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks) return false; // Don't break after very short return types (e.g. "void") as that is often // unexpected. if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) { if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None) return false; } // If binary operators are moved to the next line (including commas for some // styles of constructor initializers), that's always ok. if (!Current.isOneOf(TT_BinaryOperator, tok::comma) && State.Stack.back().NoLineBreakInOperand) return false; if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr)) return false; return !State.Stack.back().NoLineBreak; } bool ContinuationIndenter::mustBreak(const LineState &State) { const FormatToken &Current = *State.NextToken; const FormatToken &Previous = *Current.Previous; if (Current.MustBreakBefore || Current.is(TT_InlineASMColon)) return true; if (State.Stack.back().BreakBeforeClosingBrace && Current.closesBlockOrBlockTypeList(Style)) return true; if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection) return true; if (Style.Language == FormatStyle::LK_ObjC && Current.ObjCSelectorNameParts > 1 && Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) { return true; } if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) || (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) && Style.isCpp() && // FIXME: This is a temporary workaround for the case where clang-format // sets BreakBeforeParameter to avoid bin packing and this creates a // completely unnecessary line break after a template type that isn't // line-wrapped. (Previous.NestingLevel == 1 || Style.BinPackParameters)) || (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) && Previous.isNot(tok::question)) || (!Style.BreakBeforeTernaryOperators && Previous.is(TT_ConditionalExpr))) && State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() && !Current.isOneOf(tok::r_paren, tok::r_brace)) return true; if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) || (Previous.is(TT_ArrayInitializerLSquare) && Previous.ParameterCount > 1) || opensProtoMessageField(Previous, Style)) && Style.ColumnLimit > 0 && getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 > getColumnLimit(State)) return true; const FormatToken &BreakConstructorInitializersToken = Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon ? Previous : Current; if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) && (State.Column + State.Line->Last->TotalLength - Previous.TotalLength > getColumnLimit(State) || State.Stack.back().BreakBeforeParameter) && (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All || Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon || Style.ColumnLimit != 0)) return true; if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) && State.Line->startsWith(TT_ObjCMethodSpecifier)) return true; if (Current.is(TT_SelectorName) && !Previous.is(tok::at) && State.Stack.back().ObjCSelectorNameFound && State.Stack.back().BreakBeforeParameter) return true; unsigned NewLineColumn = getNewLineColumn(State); if (Current.isMemberAccess() && Style.ColumnLimit != 0 && State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit && (State.Column > NewLineColumn || Current.NestingLevel < State.StartOfLineLevel)) return true; if (startsSegmentOfBuilderTypeCall(Current) && (State.Stack.back().CallContinuation != 0 || State.Stack.back().BreakBeforeParameter) && // JavaScript is treated different here as there is a frequent pattern: // SomeFunction(function() { // ... // }.bind(...)); // FIXME: We should find a more generic solution to this problem. !(State.Column <= NewLineColumn && Style.Language == FormatStyle::LK_JavaScript) && !(Previous.closesScopeAfterBlock() && State.Column <= NewLineColumn)) return true; // If the template declaration spans multiple lines, force wrap before the // function/class declaration if (Previous.ClosesTemplateDeclaration && State.Stack.back().BreakBeforeParameter && Current.CanBreakBefore) return true; if (State.Column <= NewLineColumn) return false; if (Style.AlwaysBreakBeforeMultilineStrings && (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth || Previous.is(tok::comma) || Current.NestingLevel < 2) && !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at, Keywords.kw_dollar) && !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) && nextIsMultilineString(State)) return true; // Using CanBreakBefore here and below takes care of the decision whether the // current style uses wrapping before or after operators for the given // operator. if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) { // If we need to break somewhere inside the LHS of a binary expression, we // should also break after the operator. Otherwise, the formatting would // hide the operator precedence, e.g. in: // if (aaaaaaaaaaaaaa == // bbbbbbbbbbbbbb && c) {.. // For comparisons, we only apply this rule, if the LHS is a binary // expression itself as otherwise, the line breaks seem superfluous. // We need special cases for ">>" which we have split into two ">" while // lexing in order to make template parsing easier. bool IsComparison = (Previous.getPrecedence() == prec::Relational || Previous.getPrecedence() == prec::Equality || Previous.getPrecedence() == prec::Spaceship) && Previous.Previous && Previous.Previous->isNot(TT_BinaryOperator); // For >>. bool LHSIsBinaryExpr = Previous.Previous && Previous.Previous->EndsBinaryExpression; if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() && Previous.getPrecedence() != prec::Assignment && State.Stack.back().BreakBeforeParameter) return true; } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore && State.Stack.back().BreakBeforeParameter) { return true; } // Same as above, but for the first "<<" operator. if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) && State.Stack.back().BreakBeforeParameter && State.Stack.back().FirstLessLess == 0) return true; if (Current.NestingLevel == 0 && !Current.isTrailingComment()) { // Always break after "template <...>" and leading annotations. This is only // 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 Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No; if (Previous.is(TT_FunctionAnnotationRParen)) return true; if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) && Current.isNot(TT_LeadingJavaAnnotation)) return true; } // If the return type spans multiple lines, wrap before the function name. if ((Current.is(TT_FunctionDeclarationName) || (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) && !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter) return true; // The following could be precomputed as they do not depend on the state. // However, as they should take effect only if the UnwrappedLine does not fit // into the ColumnLimit, they are checked here in the ContinuationIndenter. if (Style.ColumnLimit != 0 && Previous.BlockKind == BK_Block && Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment)) return true; if (Current.is(tok::lessless) && ((Previous.is(tok::identifier) && Previous.TokenText == "endl") || (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") || Previous.TokenText == "\'\\n\'")))) return true; if (Previous.is(TT_BlockComment) && Previous.IsMultiline) return true; if (State.NoContinuation) return true; return false; } unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline, bool DryRun, unsigned ExtraSpaces) { const FormatToken &Current = *State.NextToken; assert(!State.Stack.empty()); State.NoContinuation = false; if ((Current.is(TT_ImplicitStringLiteral) && (Current.Previous->Tok.getIdentifierInfo() == nullptr || Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() == tok::pp_not_keyword))) { unsigned EndColumn = SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd()); if (Current.LastNewlineOffset != 0) { // If there is a newline within this token, the final column will solely // determined by the current end column. State.Column = EndColumn; } else { unsigned StartColumn = SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin()); assert(EndColumn >= StartColumn); State.Column += EndColumn - StartColumn; } moveStateToNextToken(State, DryRun, /*Newline=*/false); return 0; } unsigned Penalty = 0; if (Newline) Penalty = addTokenOnNewLine(State, DryRun); else addTokenOnCurrentLine(State, DryRun, ExtraSpaces); return moveStateToNextToken(State, DryRun, Newline) + Penalty; } void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun, unsigned ExtraSpaces) { FormatToken &Current = *State.NextToken; const FormatToken &Previous = *State.NextToken->Previous; if (Current.is(tok::equal) && (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) && State.Stack.back().VariablePos == 0) { State.Stack.back().VariablePos = State.Column; // Move over * and & if they are bound to the variable name. const FormatToken *Tok = &Previous; while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) { State.Stack.back().VariablePos -= Tok->ColumnWidth; if (Tok->SpacesRequiredBefore != 0) break; Tok = Tok->Previous; } if (Previous.PartOfMultiVariableDeclStmt) State.Stack.back().LastSpace = State.Stack.back().VariablePos; } unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces; // Indent preprocessor directives after the hash if required. int PPColumnCorrection = 0; if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash && Previous.is(tok::hash) && State.FirstIndent > 0 && (State.Line->Type == LT_PreprocessorDirective || State.Line->Type == LT_ImportStatement)) { Spaces += State.FirstIndent; // For preprocessor indent with tabs, State.Column will be 1 because of the // hash. This causes second-level indents onward to have an extra space // after the tabs. We avoid this misalignment by subtracting 1 from the // column value passed to replaceWhitespace(). if (Style.UseTab != FormatStyle::UT_Never) PPColumnCorrection = -1; } if (!DryRun) Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces, State.Column + Spaces + PPColumnCorrection); // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance // declaration unless there is multiple inheritance. if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma && Current.is(TT_InheritanceColon)) State.Stack.back().NoLineBreak = true; if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon && Previous.is(TT_InheritanceColon)) State.Stack.back().NoLineBreak = true; if (Current.is(TT_SelectorName) && !State.Stack.back().ObjCSelectorNameFound) { unsigned MinIndent = std::max(State.FirstIndent + Style.ContinuationIndentWidth, State.Stack.back().Indent); unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth; if (Current.LongestObjCSelectorName == 0) State.Stack.back().AlignColons = false; else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos) State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName; else State.Stack.back().ColonPos = FirstColonPos; } // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by // disallowing any further line breaks if there is no line break after the // opening parenthesis. Don't break if it doesn't conserve columns. if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak && Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) && State.Column > getNewLineColumn(State) && (!Previous.Previous || !Previous.Previous->isOneOf( tok::kw_for, tok::kw_while, tok::kw_switch)) && // Don't do this for simple (no expressions) one-argument function calls // as that feels like needlessly wasting whitespace, e.g.: // // caaaaaaaaaaaall( // caaaaaaaaaaaall( // caaaaaaaaaaaall( // caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa)))); Current.FakeLParens.size() > 0 && Current.FakeLParens.back() > prec::Unknown) State.Stack.back().NoLineBreak = true; if (Previous.is(TT_TemplateString) && Previous.opensScope()) State.Stack.back().NoLineBreak = true; if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign && Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) && (Current.isNot(TT_LineComment) || Previous.BlockKind == BK_BracedInit)) State.Stack.back().Indent = State.Column + Spaces; if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style)) State.Stack.back().NoLineBreak = true; if (startsSegmentOfBuilderTypeCall(Current) && State.Column > getNewLineColumn(State)) State.Stack.back().ContainsUnwrappedBuilder = true; if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java) State.Stack.back().NoLineBreak = true; if (Current.isMemberAccess() && Previous.is(tok::r_paren) && (Previous.MatchingParen && (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10))) // If there is a function call with long parameters, break before trailing // calls. This prevents things like: // EXPECT_CALL(SomeLongParameter).Times( // 2); // We don't want to do this for short parameters as they can just be // indexes. State.Stack.back().NoLineBreak = true; // Don't allow the RHS of an operator to be split over multiple lines unless // there is a line-break right after the operator. // Exclude relational operators, as there, it is always more desirable to // have the LHS 'left' of the RHS. const FormatToken *P = Current.getPreviousNonComment(); if (!Current.is(tok::comment) && P && (P->isOneOf(TT_BinaryOperator, tok::comma) || (P->is(TT_ConditionalExpr) && P->is(tok::colon))) && !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) && P->getPrecedence() != prec::Assignment && P->getPrecedence() != prec::Relational && P->getPrecedence() != prec::Spaceship) { bool BreakBeforeOperator = P->MustBreakBefore || P->is(tok::lessless) || (P->is(TT_BinaryOperator) && Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) || (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators); // Don't do this if there are only two operands. In these cases, there is // always a nice vertical separation between them and the extra line break // does not help. bool HasTwoOperands = P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr); if ((!BreakBeforeOperator && !(HasTwoOperands && Style.AlignOperands)) || (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator)) State.Stack.back().NoLineBreakInOperand = true; } State.Column += Spaces; if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) && Previous.Previous && (Previous.Previous->isOneOf(tok::kw_if, tok::kw_for) || Previous.Previous->endsSequence(tok::kw_constexpr, tok::kw_if))) { // Treat the condition inside an if as if it was a second function // parameter, i.e. let nested calls have a continuation indent. State.Stack.back().LastSpace = State.Column; State.Stack.back().NestedBlockIndent = State.Column; } else if (!Current.isOneOf(tok::comment, tok::caret) && ((Previous.is(tok::comma) && !Previous.is(TT_OverloadedOperator)) || (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) { State.Stack.back().LastSpace = State.Column; } else if (Previous.is(TT_CtorInitializerColon) && Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) { State.Stack.back().Indent = State.Column; State.Stack.back().LastSpace = State.Column; } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr, TT_CtorInitializerColon)) && ((Previous.getPrecedence() != prec::Assignment && (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 || Previous.NextOperator)) || Current.StartsBinaryExpression)) { // Indent relative to the RHS of the expression unless this is a simple // assignment without binary expression on the RHS. Also indent relative to // unary operators and the colons of constructor initializers. if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None) State.Stack.back().LastSpace = State.Column; } else if (Previous.is(TT_InheritanceColon)) { State.Stack.back().Indent = State.Column; State.Stack.back().LastSpace = State.Column; } else if (Previous.opensScope()) { // If a function has a trailing call, indent all parameters from the // opening parenthesis. This avoids confusing indents like: // OuterFunction(InnerFunctionCall( // break // ParameterToInnerFunction)) // break // .SecondInnerFunctionCall(); bool HasTrailingCall = false; if (Previous.MatchingParen) { const FormatToken *Next = Previous.MatchingParen->getNextNonComment(); HasTrailingCall = Next && Next->isMemberAccess(); } if (HasTrailingCall && State.Stack.size() > 1 && State.Stack[State.Stack.size() - 2].CallContinuation == 0) State.Stack.back().LastSpace = State.Column; } } unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State, bool DryRun) { FormatToken &Current = *State.NextToken; const FormatToken &Previous = *State.NextToken->Previous; // Extra penalty that needs to be added because of the way certain line // breaks are chosen. unsigned Penalty = 0; const FormatToken *PreviousNonComment = Current.getPreviousNonComment(); const FormatToken *NextNonComment = Previous.getNextNonComment(); if (!NextNonComment) NextNonComment = &Current; // The first line break on any NestingLevel causes an extra penalty in order // prefer similar line breaks. if (!State.Stack.back().ContainsLineBreak) Penalty += 15; State.Stack.back().ContainsLineBreak = true; Penalty += State.NextToken->SplitPenalty; // Breaking before the first "<<" is generally not desirable if the LHS is // short. Also always add the penalty if the LHS is split over multiple lines // to avoid unnecessary line breaks that just work around this penalty. if (NextNonComment->is(tok::lessless) && State.Stack.back().FirstLessLess == 0 && (State.Column <= Style.ColumnLimit / 3 || State.Stack.back().BreakBeforeParameter)) Penalty += Style.PenaltyBreakFirstLessLess; State.Column = getNewLineColumn(State); // Indent nested blocks relative to this column, unless in a very specific // JavaScript special case where: // // var loooooong_name = // function() { // // code // } // // is common and should be formatted like a free-standing function. The same // goes for wrapping before the lambda return type arrow. if (!Current.is(TT_LambdaArrow) && (Style.Language != FormatStyle::LK_JavaScript || Current.NestingLevel != 0 || !PreviousNonComment || !PreviousNonComment->is(tok::equal) || !Current.isOneOf(Keywords.kw_async, Keywords.kw_function))) State.Stack.back().NestedBlockIndent = State.Column; if (NextNonComment->isMemberAccess()) { if (State.Stack.back().CallContinuation == 0) State.Stack.back().CallContinuation = State.Column; } else if (NextNonComment->is(TT_SelectorName)) { if (!State.Stack.back().ObjCSelectorNameFound) { if (NextNonComment->LongestObjCSelectorName == 0) { State.Stack.back().AlignColons = false; } else { State.Stack.back().ColonPos = (shouldIndentWrappedSelectorName(Style, State.Line->Type) ? std::max(State.Stack.back().Indent, State.FirstIndent + Style.ContinuationIndentWidth) : State.Stack.back().Indent) + std::max(NextNonComment->LongestObjCSelectorName, NextNonComment->ColumnWidth); } } else if (State.Stack.back().AlignColons && State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) { State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth; } } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) && PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) { // FIXME: This is hacky, find a better way. The problem is that in an ObjC // method expression, the block should be aligned to the line starting it, // e.g.: // [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason // ^(int *i) { // // ... // }]; // Thus, we set LastSpace of the next higher NestingLevel, to which we move // when we consume all of the "}"'s FakeRParens at the "{". if (State.Stack.size() > 1) State.Stack[State.Stack.size() - 2].LastSpace = std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) + Style.ContinuationIndentWidth; } if ((PreviousNonComment && PreviousNonComment->isOneOf(tok::comma, tok::semi) && !State.Stack.back().AvoidBinPacking) || Previous.is(TT_BinaryOperator)) State.Stack.back().BreakBeforeParameter = false; if (PreviousNonComment && PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) && Current.NestingLevel == 0) State.Stack.back().BreakBeforeParameter = false; if (NextNonComment->is(tok::question) || (PreviousNonComment && PreviousNonComment->is(tok::question))) State.Stack.back().BreakBeforeParameter = true; if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore) State.Stack.back().BreakBeforeParameter = false; if (!DryRun) { unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1; if (Current.is(tok::r_brace) && Current.MatchingParen && // Only strip trailing empty lines for l_braces that have children, i.e. // for function expressions (lambdas, arrows, etc). !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; } unsigned Newlines = std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep)); bool ContinuePPDirective = State.Line->InPPDirective && State.Line->Type != LT_ImportStatement; Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column, ContinuePPDirective); } if (!Current.isTrailingComment()) State.Stack.back().LastSpace = State.Column; if (Current.is(tok::lessless)) // If we are breaking before a "<<", we always want to indent relative to // RHS. This is necessary only for "<<", as we special-case it and don't // always indent relative to the RHS. State.Stack.back().LastSpace += 3; // 3 -> width of "<< ". State.StartOfLineLevel = Current.NestingLevel; State.LowestLevelOnLine = Current.NestingLevel; // Any break on this level means that the parent level has been broken // and we need to avoid bin packing there. bool NestedBlockSpecialCase = !Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 && State.Stack[State.Stack.size() - 2].NestedBlockInlined; if (!NestedBlockSpecialCase) for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i) State.Stack[i].BreakBeforeParameter = true; if (PreviousNonComment && !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) && (PreviousNonComment->isNot(TT_TemplateCloser) || Current.NestingLevel != 0) && !PreviousNonComment->isOneOf( TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation, TT_LeadingJavaAnnotation) && Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope()) State.Stack.back().BreakBeforeParameter = true; // If we break after { or the [ of an array initializer, we should also break // before the corresponding } or ]. if (PreviousNonComment && (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) || opensProtoMessageField(*PreviousNonComment, Style))) State.Stack.back().BreakBeforeClosingBrace = true; if (State.Stack.back().AvoidBinPacking) { // If we are breaking after '(', '{', '<', or this is the break after a ':' // to start a member initializater list in a constructor, this should not // be considered bin packing unless the relevant AllowAll option is false or // this is a dict/object literal. bool PreviousIsBreakingCtorInitializerColon = Previous.is(TT_CtorInitializerColon) && Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon; if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) || PreviousIsBreakingCtorInitializerColon) || (!Style.AllowAllParametersOfDeclarationOnNextLine && State.Line->MustBeDeclaration) || (!Style.AllowAllArgumentsOnNextLine && !State.Line->MustBeDeclaration) || (!Style.AllowAllConstructorInitializersOnNextLine && PreviousIsBreakingCtorInitializerColon) || Previous.is(TT_DictLiteral)) State.Stack.back().BreakBeforeParameter = true; // If we are breaking after a ':' to start a member initializer list, // and we allow all arguments on the next line, we should not break // before the next parameter. if (PreviousIsBreakingCtorInitializerColon && Style.AllowAllConstructorInitializersOnNextLine) State.Stack.back().BreakBeforeParameter = false; } return Penalty; } unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) { if (!State.NextToken || !State.NextToken->Previous) return 0; FormatToken &Current = *State.NextToken; const FormatToken &Previous = *Current.Previous; // If we are continuing an expression, we want to use the continuation indent. unsigned ContinuationIndent = std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) + Style.ContinuationIndentWidth; const FormatToken *PreviousNonComment = Current.getPreviousNonComment(); const FormatToken *NextNonComment = Previous.getNextNonComment(); if (!NextNonComment) NextNonComment = &Current; // Java specific bits. if (Style.Language == FormatStyle::LK_Java && Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends)) return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent + Style.ContinuationIndentWidth); if (NextNonComment->is(tok::l_brace) && NextNonComment->BlockKind == BK_Block) return Current.NestingLevel == 0 ? State.FirstIndent : State.Stack.back().Indent; if ((Current.isOneOf(tok::r_brace, tok::r_square) || (Current.is(tok::greater) && (Style.Language == FormatStyle::LK_Proto || Style.Language == FormatStyle::LK_TextProto))) && State.Stack.size() > 1) { if (Current.closesBlockOrBlockTypeList(Style)) return State.Stack[State.Stack.size() - 2].NestedBlockIndent; if (Current.MatchingParen && Current.MatchingParen->BlockKind == BK_BracedInit) return State.Stack[State.Stack.size() - 2].LastSpace; return State.FirstIndent; } // Indent a closing parenthesis at the previous level if followed by a semi, // const, or opening brace. This allows indentations such as: // foo( // a, // ); // int Foo::getter( // // // ) const { // return foo; // } // function foo( // a, // ) { // code(); // // } if (Current.is(tok::r_paren) && State.Stack.size() > 1 && (!Current.Next || Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace))) return State.Stack[State.Stack.size() - 2].LastSpace; if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope()) return State.Stack[State.Stack.size() - 2].LastSpace; if (Current.is(tok::identifier) && Current.Next && (Current.Next->is(TT_DictLiteral) || ((Style.Language == FormatStyle::LK_Proto || Style.Language == FormatStyle::LK_TextProto) && Current.Next->isOneOf(tok::less, tok::l_brace)))) return State.Stack.back().Indent; if (NextNonComment->is(TT_ObjCStringLiteral) && State.StartOfStringLiteral != 0) return State.StartOfStringLiteral - 1; if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0) return State.StartOfStringLiteral; if (NextNonComment->is(tok::lessless) && State.Stack.back().FirstLessLess != 0) return State.Stack.back().FirstLessLess; if (NextNonComment->isMemberAccess()) { if (State.Stack.back().CallContinuation == 0) return ContinuationIndent; return State.Stack.back().CallContinuation; } if (State.Stack.back().QuestionColumn != 0 && ((NextNonComment->is(tok::colon) && NextNonComment->is(TT_ConditionalExpr)) || Previous.is(TT_ConditionalExpr))) return State.Stack.back().QuestionColumn; if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0) return State.Stack.back().VariablePos; if ((PreviousNonComment && (PreviousNonComment->ClosesTemplateDeclaration || PreviousNonComment->isOneOf( TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen, TT_JavaAnnotation, TT_LeadingJavaAnnotation))) || (!Style.IndentWrappedFunctionNames && NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName))) return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent); if (NextNonComment->is(TT_SelectorName)) { if (!State.Stack.back().ObjCSelectorNameFound) { unsigned MinIndent = State.Stack.back().Indent; if (shouldIndentWrappedSelectorName(Style, State.Line->Type)) MinIndent = std::max(MinIndent, State.FirstIndent + Style.ContinuationIndentWidth); // If LongestObjCSelectorName is 0, we are indenting the first // part of an ObjC selector (or a selector component which is // not colon-aligned due to block formatting). // // Otherwise, we are indenting a subsequent part of an ObjC // selector which should be colon-aligned to the longest // component of the ObjC selector. // // In either case, we want to respect Style.IndentWrappedFunctionNames. return MinIndent + std::max(NextNonComment->LongestObjCSelectorName, NextNonComment->ColumnWidth) - NextNonComment->ColumnWidth; } if (!State.Stack.back().AlignColons) return State.Stack.back().Indent; if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth) return State.Stack.back().ColonPos - NextNonComment->ColumnWidth; return State.Stack.back().Indent; } if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr)) return State.Stack.back().ColonPos; if (NextNonComment->is(TT_ArraySubscriptLSquare)) { if (State.Stack.back().StartOfArraySubscripts != 0) return State.Stack.back().StartOfArraySubscripts; return ContinuationIndent; } // This ensure that we correctly format ObjC methods calls without inputs, // i.e. where the last element isn't selector like: [callee method]; if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 && NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr)) return State.Stack.back().Indent; if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) || Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon)) return ContinuationIndent; if (PreviousNonComment && PreviousNonComment->is(tok::colon) && PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) return ContinuationIndent; if (NextNonComment->is(TT_CtorInitializerComma)) return State.Stack.back().Indent; if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) && Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) return State.Stack.back().Indent; if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) && Style.BreakInheritanceList == FormatStyle::BILS_AfterColon) return State.Stack.back().Indent; if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon, TT_InheritanceComma)) return State.FirstIndent + Style.ConstructorInitializerIndentWidth; if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() && !Current.isOneOf(tok::colon, tok::comment)) return ContinuationIndent; if (Current.is(TT_ProtoExtensionLSquare)) return State.Stack.back().Indent; if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment && !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma)) // Ensure that we fall back to the continuation indent width instead of // just flushing continuations left. return State.Stack.back().Indent + Style.ContinuationIndentWidth; return State.Stack.back().Indent; } unsigned ContinuationIndenter::moveStateToNextToken(LineState &State, bool DryRun, bool Newline) { assert(State.Stack.size()); const FormatToken &Current = *State.NextToken; if (Current.isOneOf(tok::comma, TT_BinaryOperator)) State.Stack.back().NoLineBreakInOperand = false; if (Current.is(TT_InheritanceColon)) State.Stack.back().AvoidBinPacking = true; if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) { if (State.Stack.back().FirstLessLess == 0) State.Stack.back().FirstLessLess = State.Column; else State.Stack.back().LastOperatorWrapped = Newline; } if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless)) State.Stack.back().LastOperatorWrapped = Newline; if (Current.is(TT_ConditionalExpr) && Current.Previous && !Current.Previous->is(TT_ConditionalExpr)) State.Stack.back().LastOperatorWrapped = Newline; if (Current.is(TT_ArraySubscriptLSquare) && State.Stack.back().StartOfArraySubscripts == 0) State.Stack.back().StartOfArraySubscripts = State.Column; if (Style.BreakBeforeTernaryOperators && Current.is(tok::question)) State.Stack.back().QuestionColumn = State.Column; if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) { const FormatToken *Previous = Current.Previous; while (Previous && Previous->isTrailingComment()) Previous = Previous->Previous; if (Previous && Previous->is(tok::question)) State.Stack.back().QuestionColumn = State.Column; } if (!Current.opensScope() && !Current.closesScope() && !Current.is(TT_PointerOrReference)) State.LowestLevelOnLine = std::min(State.LowestLevelOnLine, Current.NestingLevel); if (Current.isMemberAccess()) State.Stack.back().StartOfFunctionCall = !Current.NextOperator ? 0 : State.Column; if (Current.is(TT_SelectorName)) State.Stack.back().ObjCSelectorNameFound = true; if (Current.is(TT_CtorInitializerColon) && Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) { // Indent 2 from the column, so: // SomeClass::SomeClass() // : First(...), ... // Next(...) // ^ line up here. State.Stack.back().Indent = State.Column + (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma ? 0 : 2); State.Stack.back().NestedBlockIndent = State.Stack.back().Indent; if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) { State.Stack.back().AvoidBinPacking = true; State.Stack.back().BreakBeforeParameter = !Style.AllowAllConstructorInitializersOnNextLine; } else { State.Stack.back().BreakBeforeParameter = false; } } if (Current.is(TT_CtorInitializerColon) && Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) { State.Stack.back().Indent = State.FirstIndent + Style.ConstructorInitializerIndentWidth; State.Stack.back().NestedBlockIndent = State.Stack.back().Indent; if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) State.Stack.back().AvoidBinPacking = true; } if (Current.is(TT_InheritanceColon)) State.Stack.back().Indent = State.FirstIndent + Style.ConstructorInitializerIndentWidth; if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline) State.Stack.back().NestedBlockIndent = State.Column + Current.ColumnWidth + 1; if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow)) State.Stack.back().LastSpace = State.Column; // Insert scopes created by fake parenthesis. const FormatToken *Previous = Current.getPreviousNonComment(); // Add special behavior to support a format commonly used for JavaScript // closures: // SomeFunction(function() { // foo(); // bar(); // }, a, b, c); if (Current.isNot(tok::comment) && Previous && Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) && !Previous->is(TT_DictLiteral) && State.Stack.size() > 1 && !State.Stack.back().HasMultipleNestedBlocks) { if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline) for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i) State.Stack[i].NoLineBreak = true; State.Stack[State.Stack.size() - 2].NestedBlockInlined = false; } if (Previous && (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) || Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) && !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) { State.Stack.back().NestedBlockInlined = !Newline && (Previous->isNot(tok::l_paren) || Previous->ParameterCount > 1); } moveStatePastFakeLParens(State, Newline); moveStatePastScopeCloser(State); bool AllowBreak = !State.Stack.back().NoLineBreak && !State.Stack.back().NoLineBreakInOperand; moveStatePastScopeOpener(State, Newline); moveStatePastFakeRParens(State); if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0) State.StartOfStringLiteral = State.Column + 1; if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0) State.StartOfStringLiteral = State.Column + 1; else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0) State.StartOfStringLiteral = State.Column; else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) && !Current.isStringLiteral()) State.StartOfStringLiteral = 0; State.Column += Current.ColumnWidth; State.NextToken = State.NextToken->Next; unsigned Penalty = handleEndOfLine(Current, State, DryRun, AllowBreak, Newline); if (Current.Role) Current.Role->formatFromToken(State, this, DryRun); // If the previous has a special role, let it consume tokens as appropriate. // It is necessary to start at the previous token for the only implemented // role (comma separated list). That way, the decision whether or not to break // after the "{" is already done and both options are tried and evaluated. // FIXME: This is ugly, find a better way. if (Previous && Previous->Role) Penalty += Previous->Role->formatAfterToken(State, this, DryRun); return Penalty; } void ContinuationIndenter::moveStatePastFakeLParens(LineState &State, bool Newline) { const FormatToken &Current = *State.NextToken; const FormatToken *Previous = Current.getPreviousNonComment(); // Don't add extra indentation for the first fake parenthesis after // 'return', assignments or opening <({[. The indentation for these cases // is special cased. bool SkipFirstExtraIndent = (Previous && (Previous->opensScope() || Previous->isOneOf(tok::semi, tok::kw_return) || (Previous->getPrecedence() == prec::Assignment && Style.AlignOperands) || Previous->is(TT_ObjCMethodExpr))); for (SmallVectorImpl::const_reverse_iterator I = Current.FakeLParens.rbegin(), E = Current.FakeLParens.rend(); I != E; ++I) { ParenState NewParenState = State.Stack.back(); NewParenState.Tok = nullptr; NewParenState.ContainsLineBreak = false; NewParenState.LastOperatorWrapped = true; NewParenState.NoLineBreak = NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand; // Don't propagate AvoidBinPacking into subexpressions of arg/param lists. if (*I > prec::Comma) NewParenState.AvoidBinPacking = false; // Indent from 'LastSpace' unless these are fake parentheses encapsulating // a builder type call after 'return' or, if the alignment after opening // brackets is disabled. if (!Current.isTrailingComment() && (Style.AlignOperands || *I < prec::Assignment) && (!Previous || Previous->isNot(tok::kw_return) || (Style.Language != FormatStyle::LK_Java && *I > 0)) && (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign || *I != prec::Comma || Current.NestingLevel == 0)) NewParenState.Indent = std::max(std::max(State.Column, NewParenState.Indent), State.Stack.back().LastSpace); // Do not indent relative to the fake parentheses inserted for "." or "->". // This is a special case to make the following to statements consistent: // OuterFunction(InnerFunctionCall( // break // ParameterToInnerFunction)); // OuterFunction(SomeObject.InnerFunctionCall( // break // ParameterToInnerFunction)); if (*I > prec::Unknown) NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column); if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) && Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign) NewParenState.StartOfFunctionCall = State.Column; // Always indent conditional expressions. Never indent expression where // the 'operator' is ',', ';' or an assignment (i.e. *I <= // prec::Assignment) as those have different indentation rules. Indent // other expression, unless the indentation needs to be skipped. if (*I == prec::Conditional || (!SkipFirstExtraIndent && *I > prec::Assignment && !Current.isTrailingComment())) NewParenState.Indent += Style.ContinuationIndentWidth; if ((Previous && !Previous->opensScope()) || *I != prec::Comma) NewParenState.BreakBeforeParameter = false; State.Stack.push_back(NewParenState); SkipFirstExtraIndent = false; } } void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) { for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) { unsigned VariablePos = State.Stack.back().VariablePos; if (State.Stack.size() == 1) { // Do not pop the last element. break; } State.Stack.pop_back(); State.Stack.back().VariablePos = VariablePos; } } void ContinuationIndenter::moveStatePastScopeOpener(LineState &State, bool Newline) { const FormatToken &Current = *State.NextToken; if (!Current.opensScope()) return; if (Current.MatchingParen && Current.BlockKind == BK_Block) { moveStateToNewBlock(State); return; } unsigned NewIndent; unsigned LastSpace = State.Stack.back().LastSpace; bool AvoidBinPacking; bool BreakBeforeParameter = false; unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall, State.Stack.back().NestedBlockIndent); if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) || opensProtoMessageField(Current, Style)) { if (Current.opensBlockOrBlockTypeList(Style)) { NewIndent = Style.IndentWidth + std::min(State.Column, State.Stack.back().NestedBlockIndent); } else { NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth; } const FormatToken *NextNoComment = Current.getNextNonComment(); bool EndsInComma = Current.MatchingParen && Current.MatchingParen->Previous && Current.MatchingParen->Previous->is(tok::comma); AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) || Style.Language == FormatStyle::LK_Proto || Style.Language == FormatStyle::LK_TextProto || !Style.BinPackArguments || (NextNoComment && NextNoComment->isOneOf(TT_DesignatedInitializerPeriod, TT_DesignatedInitializerLSquare)); BreakBeforeParameter = EndsInComma; if (Current.ParameterCount > 1) NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1); } else { NewIndent = Style.ContinuationIndentWidth + std::max(State.Stack.back().LastSpace, State.Stack.back().StartOfFunctionCall); // Ensure that different different brackets force relative alignment, e.g.: // void SomeFunction(vector< // break // int> v); // FIXME: We likely want to do this for more combinations of brackets. if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) { NewIndent = std::max(NewIndent, State.Stack.back().Indent); LastSpace = std::max(LastSpace, State.Stack.back().Indent); } bool EndsInComma = Current.MatchingParen && Current.MatchingParen->getPreviousNonComment() && Current.MatchingParen->getPreviousNonComment()->is(tok::comma); // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters // for backwards compatibility. bool ObjCBinPackProtocolList = (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto && Style.BinPackParameters) || Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always; bool BinPackDeclaration = (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) || (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList); AvoidBinPacking = (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) || (State.Line->MustBeDeclaration && !BinPackDeclaration) || (!State.Line->MustBeDeclaration && !Style.BinPackArguments) || (Style.ExperimentalAutoDetectBinPacking && (Current.PackingKind == PPK_OnePerLine || (!BinPackInconclusiveFunctions && Current.PackingKind == PPK_Inconclusive))); if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen) { if (Style.ColumnLimit) { // If this '[' opens an ObjC call, determine whether all parameters fit // into one line and put one per line if they don't. if (getLengthToMatchingParen(Current, State.Stack) + State.Column > getColumnLimit(State)) BreakBeforeParameter = true; } else { // For ColumnLimit = 0, we have to figure out whether there is or has to // be a line break within this call. for (const FormatToken *Tok = &Current; Tok && Tok != Current.MatchingParen; Tok = Tok->Next) { if (Tok->MustBreakBefore || (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) { BreakBeforeParameter = true; break; } } } } if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) BreakBeforeParameter = true; } // Generally inherit NoLineBreak from the current scope to nested scope. // However, don't do this for non-empty nested blocks, dict literals and // array literals as these follow different indentation rules. bool NoLineBreak = Current.Children.empty() && !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) && (State.Stack.back().NoLineBreak || State.Stack.back().NoLineBreakInOperand || (Current.is(TT_TemplateOpener) && State.Stack.back().ContainsUnwrappedBuilder)); State.Stack.push_back( ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak)); State.Stack.back().NestedBlockIndent = NestedBlockIndent; State.Stack.back().BreakBeforeParameter = BreakBeforeParameter; State.Stack.back().HasMultipleNestedBlocks = Current.BlockParameterCount > 1; State.Stack.back().IsInsideObjCArrayLiteral = Current.is(TT_ArrayInitializerLSquare) && Current.Previous && Current.Previous->is(tok::at); } void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) { const FormatToken &Current = *State.NextToken; if (!Current.closesScope()) return; // If we encounter a closing ), ], } or >, we can remove a level from our // stacks. if (State.Stack.size() > 1 && (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) || (Current.is(tok::r_brace) && State.NextToken != State.Line->First) || State.NextToken->is(TT_TemplateCloser) || (Current.is(tok::greater) && Current.is(TT_DictLiteral)))) State.Stack.pop_back(); // Reevaluate whether ObjC message arguments fit into one line. // If a receiver spans multiple lines, e.g.: // [[object block:^{ // return 42; // }] a:42 b:42]; // BreakBeforeParameter is calculated based on an incorrect assumption // (it is checked whether the whole expression fits into one line without // considering a line break inside a message receiver). // We check whether arguements fit after receiver scope closer (into the same // line). if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen && Current.MatchingParen->Previous) { const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous; if (CurrentScopeOpener.is(TT_ObjCMethodExpr) && CurrentScopeOpener.MatchingParen) { int NecessarySpaceInLine = getLengthToMatchingParen(CurrentScopeOpener, State.Stack) + CurrentScopeOpener.TotalLength - Current.TotalLength - 1; if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <= Style.ColumnLimit) State.Stack.back().BreakBeforeParameter = false; } } if (Current.is(tok::r_square)) { // If this ends the array subscript expr, reset the corresponding value. const FormatToken *NextNonComment = Current.getNextNonComment(); if (NextNonComment && NextNonComment->isNot(tok::l_square)) State.Stack.back().StartOfArraySubscripts = 0; } } void ContinuationIndenter::moveStateToNewBlock(LineState &State) { unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent; // ObjC block sometimes follow special indentation rules. unsigned NewIndent = NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace) ? Style.ObjCBlockIndentWidth : Style.IndentWidth); State.Stack.push_back(ParenState(State.NextToken, NewIndent, State.Stack.back().LastSpace, /*AvoidBinPacking=*/true, /*NoLineBreak=*/false)); State.Stack.back().NestedBlockIndent = NestedBlockIndent; State.Stack.back().BreakBeforeParameter = true; } static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn, unsigned TabWidth, encoding::Encoding Encoding) { size_t LastNewlinePos = Text.find_last_of("\n"); if (LastNewlinePos == StringRef::npos) { return StartColumn + encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding); } else { return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos), /*StartColumn=*/0, TabWidth, Encoding); } } unsigned ContinuationIndenter::reformatRawStringLiteral( const FormatToken &Current, LineState &State, const FormatStyle &RawStringStyle, bool DryRun, bool Newline) { unsigned StartColumn = State.Column - Current.ColumnWidth; StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText); StringRef NewDelimiter = getCanonicalRawStringDelimiter(Style, RawStringStyle.Language); if (NewDelimiter.empty() || OldDelimiter.empty()) NewDelimiter = OldDelimiter; // The text of a raw string is between the leading 'R"delimiter(' and the // trailing 'delimiter)"'. unsigned OldPrefixSize = 3 + OldDelimiter.size(); unsigned OldSuffixSize = 2 + OldDelimiter.size(); // We create a virtual text environment which expects a null-terminated // string, so we cannot use StringRef. std::string RawText = Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize); if (NewDelimiter != OldDelimiter) { // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the // raw string. std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str(); if (StringRef(RawText).contains(CanonicalDelimiterSuffix)) NewDelimiter = OldDelimiter; } unsigned NewPrefixSize = 3 + NewDelimiter.size(); unsigned NewSuffixSize = 2 + NewDelimiter.size(); // The first start column is the column the raw text starts after formatting. unsigned FirstStartColumn = StartColumn + NewPrefixSize; // The next start column is the intended indentation a line break inside // the raw string at level 0. It is determined by the following rules: // - if the content starts on newline, it is one level more than the current // indent, and // - if the content does not start on a newline, it is the first start // column. // These rules have the advantage that the formatted content both does not // violate the rectangle rule and visually flows within the surrounding // source. bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n'; // If this token is the last parameter (checked by looking if it's followed by // `)` and is not on a newline, the base the indent off the line's nested // block indent. Otherwise, base the indent off the arguments indent, so we // can achieve: // // fffffffffff(1, 2, 3, R"pb( // key1: 1 # // key2: 2)pb"); // // fffffffffff(1, 2, 3, // R"pb( // key1: 1 # // key2: 2 // )pb"); // // fffffffffff(1, 2, 3, // R"pb( // key1: 1 # // key2: 2 // )pb", // 5); unsigned CurrentIndent = (!Newline && Current.Next && Current.Next->is(tok::r_paren)) ? State.Stack.back().NestedBlockIndent : State.Stack.back().Indent; unsigned NextStartColumn = ContentStartsOnNewline ? CurrentIndent + Style.IndentWidth : FirstStartColumn; // The last start column is the column the raw string suffix starts if it is // put on a newline. // The last start column is the intended indentation of the raw string postfix // if it is put on a newline. It is determined by the following rules: // - if the raw string prefix starts on a newline, it is the column where // that raw string prefix starts, and // - if the raw string prefix does not start on a newline, it is the current // indent. unsigned LastStartColumn = Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent; std::pair Fixes = internal::reformat( RawStringStyle, RawText, {tooling::Range(0, RawText.size())}, FirstStartColumn, NextStartColumn, LastStartColumn, "", /*Status=*/nullptr); auto NewCode = applyAllReplacements(RawText, Fixes.first); tooling::Replacements NoFixes; if (!NewCode) { return addMultilineToken(Current, State); } if (!DryRun) { if (NewDelimiter != OldDelimiter) { // In 'R"delimiter(...', the delimiter starts 2 characters after the start // of the token. SourceLocation PrefixDelimiterStart = Current.Tok.getLocation().getLocWithOffset(2); auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement( SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter)); if (PrefixErr) { llvm::errs() << "Failed to update the prefix delimiter of a raw string: " << llvm::toString(std::move(PrefixErr)) << "\n"; } // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at // position length - 1 - |delimiter|. SourceLocation SuffixDelimiterStart = Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() - 1 - OldDelimiter.size()); auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement( SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter)); if (SuffixErr) { llvm::errs() << "Failed to update the suffix delimiter of a raw string: " << llvm::toString(std::move(SuffixErr)) << "\n"; } } SourceLocation OriginLoc = Current.Tok.getLocation().getLocWithOffset(OldPrefixSize); for (const tooling::Replacement &Fix : Fixes.first) { auto Err = Whitespaces.addReplacement(tooling::Replacement( SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()), Fix.getLength(), Fix.getReplacementText())); if (Err) { llvm::errs() << "Failed to reformat raw string: " << llvm::toString(std::move(Err)) << "\n"; } } } unsigned RawLastLineEndColumn = getLastLineEndColumn( *NewCode, FirstStartColumn, Style.TabWidth, Encoding); State.Column = RawLastLineEndColumn + NewSuffixSize; // Since we're updating the column to after the raw string literal here, we // have to manually add the penalty for the prefix R"delim( over the column // limit. unsigned PrefixExcessCharacters = StartColumn + NewPrefixSize > Style.ColumnLimit ? StartColumn + NewPrefixSize - Style.ColumnLimit : 0; bool IsMultiline = ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos); if (IsMultiline) { // Break before further function parameters on all levels. for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) State.Stack[i].BreakBeforeParameter = true; } return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter; } unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current, LineState &State) { // Break before further function parameters on all levels. for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) State.Stack[i].BreakBeforeParameter = true; unsigned ColumnsUsed = State.Column; // We can only affect layout of the first and the last line, so the penalty // for all other lines is constant, and we ignore it. State.Column = Current.LastLineColumnWidth; if (ColumnsUsed > getColumnLimit(State)) return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State)); return 0; } unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current, LineState &State, bool DryRun, bool AllowBreak, bool Newline) { unsigned Penalty = 0; // Compute the raw string style to use in case this is a raw string literal // that can be reformatted. auto RawStringStyle = getRawStringStyle(Current, State); if (RawStringStyle && !Current.Finalized) { Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun, Newline); } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) { // Don't break multi-line tokens other than block comments and raw string // literals. Instead, just update the state. Penalty = addMultilineToken(Current, State); } else if (State.Line->Type != LT_ImportStatement) { // We generally don't break import statements. LineState OriginalState = State; // Whether we force the reflowing algorithm to stay strictly within the // column limit. bool Strict = false; // Whether the first non-strict attempt at reflowing did intentionally // exceed the column limit. bool Exceeded = false; std::tie(Penalty, Exceeded) = breakProtrudingToken( Current, State, AllowBreak, /*DryRun=*/true, Strict); if (Exceeded) { // If non-strict reflowing exceeds the column limit, try whether strict // reflowing leads to an overall lower penalty. LineState StrictState = OriginalState; unsigned StrictPenalty = breakProtrudingToken(Current, StrictState, AllowBreak, /*DryRun=*/true, /*Strict=*/true) .first; Strict = StrictPenalty <= Penalty; if (Strict) { Penalty = StrictPenalty; State = StrictState; } } if (!DryRun) { // If we're not in dry-run mode, apply the changes with the decision on // strictness made above. breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false, Strict); } } if (State.Column > getColumnLimit(State)) { unsigned ExcessCharacters = State.Column - getColumnLimit(State); Penalty += Style.PenaltyExcessCharacter * ExcessCharacters; } return Penalty; } // Returns the enclosing function name of a token, or the empty string if not // found. static StringRef getEnclosingFunctionName(const FormatToken &Current) { // Look for: 'function(' or 'function(' before Current. auto Tok = Current.getPreviousNonComment(); if (!Tok || !Tok->is(tok::l_paren)) return ""; Tok = Tok->getPreviousNonComment(); if (!Tok) return ""; if (Tok->is(TT_TemplateCloser)) { Tok = Tok->MatchingParen; if (Tok) Tok = Tok->getPreviousNonComment(); } if (!Tok || !Tok->is(tok::identifier)) return ""; return Tok->TokenText; } llvm::Optional ContinuationIndenter::getRawStringStyle(const FormatToken &Current, const LineState &State) { if (!Current.isStringLiteral()) return None; auto Delimiter = getRawStringDelimiter(Current.TokenText); if (!Delimiter) return None; auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter); if (!RawStringStyle && Delimiter->empty()) RawStringStyle = RawStringFormats.getEnclosingFunctionStyle( getEnclosingFunctionName(Current)); if (!RawStringStyle) return None; RawStringStyle->ColumnLimit = getColumnLimit(State); return RawStringStyle; } std::unique_ptr ContinuationIndenter::createBreakableToken(const FormatToken &Current, LineState &State, bool AllowBreak) { unsigned StartColumn = State.Column - Current.ColumnWidth; if (Current.isStringLiteral()) { // FIXME: String literal breaking is currently disabled for C#,Java and // JavaScript, as it requires strings to be merged using "+" which we // don't support. if (Style.Language == FormatStyle::LK_Java || Style.Language == FormatStyle::LK_JavaScript || Style.isCSharp() || !Style.BreakStringLiterals || !AllowBreak) return nullptr; // Don't break string literals inside preprocessor directives (except for // #define directives, as their contents are stored in separate lines and // are not affected by this check). // This way we avoid breaking code with line directives and unknown // preprocessor directives that contain long string literals. if (State.Line->Type == LT_PreprocessorDirective) return nullptr; // Exempts unterminated string literals from line breaking. The user will // likely want to terminate the string before any line breaking is done. if (Current.IsUnterminatedLiteral) return nullptr; // Don't break string literals inside Objective-C array literals (doing so // raises the warning -Wobjc-string-concatenation). if (State.Stack.back().IsInsideObjCArrayLiteral) { return nullptr; } StringRef Text = Current.TokenText; StringRef Prefix; StringRef Postfix; // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'. // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to // reduce the overhead) for each FormatToken, which is a string, so that we // don't run multiple checks here on the hot path. if ((Text.endswith(Postfix = "\"") && (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") || Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") || Text.startswith(Prefix = "u8\"") || Text.startswith(Prefix = "L\""))) || (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) { // We need this to address the case where there is an unbreakable tail // only if certain other formatting decisions have been taken. The // UnbreakableTailLength of Current is an overapproximation is that case // and we need to be correct here. unsigned UnbreakableTailLength = (State.NextToken && canBreak(State)) ? 0 : Current.UnbreakableTailLength; return llvm::make_unique( Current, StartColumn, Prefix, Postfix, UnbreakableTailLength, State.Line->InPPDirective, Encoding, Style); } } else if (Current.is(TT_BlockComment)) { if (!Style.ReflowComments || // If a comment token switches formatting, like // /* clang-format on */, we don't want to break it further, // but we may still want to adjust its indentation. switchesFormatting(Current)) { return nullptr; } return llvm::make_unique( Current, StartColumn, Current.OriginalColumn, !Current.Previous, State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF()); } else if (Current.is(TT_LineComment) && (Current.Previous == nullptr || Current.Previous->isNot(TT_ImplicitStringLiteral))) { if (!Style.ReflowComments || CommentPragmasRegex.match(Current.TokenText.substr(2)) || switchesFormatting(Current)) return nullptr; return llvm::make_unique( Current, StartColumn, Current.OriginalColumn, !Current.Previous, /*InPPDirective=*/false, Encoding, Style); } return nullptr; } std::pair ContinuationIndenter::breakProtrudingToken(const FormatToken &Current, LineState &State, bool AllowBreak, bool DryRun, bool Strict) { std::unique_ptr Token = createBreakableToken(Current, State, AllowBreak); if (!Token) return {0, false}; assert(Token->getLineCount() > 0); unsigned ColumnLimit = getColumnLimit(State); if (Current.is(TT_LineComment)) { // We don't insert backslashes when breaking line comments. ColumnLimit = Style.ColumnLimit; } if (Current.UnbreakableTailLength >= ColumnLimit) return {0, false}; // ColumnWidth was already accounted into State.Column before calling // breakProtrudingToken. unsigned StartColumn = State.Column - Current.ColumnWidth; unsigned NewBreakPenalty = Current.isStringLiteral() ? Style.PenaltyBreakString : Style.PenaltyBreakComment; // Stores whether we intentionally decide to let a line exceed the column // limit. bool Exceeded = false; // Stores whether we introduce a break anywhere in the token. bool BreakInserted = Token->introducesBreakBeforeToken(); // Store whether we inserted a new line break at the end of the previous // logical line. bool NewBreakBefore = false; // We use a conservative reflowing strategy. Reflow starts after a line is // broken or the corresponding whitespace compressed. Reflow ends as soon as a // line that doesn't get reflown with the previous line is reached. bool Reflow = false; // Keep track of where we are in the token: // Where we are in the content of the current logical line. unsigned TailOffset = 0; // The column number we're currently at. unsigned ContentStartColumn = Token->getContentStartColumn(0, /*Break=*/false); // The number of columns left in the current logical line after TailOffset. unsigned RemainingTokenColumns = Token->getRemainingLength(0, TailOffset, ContentStartColumn); // Adapt the start of the token, for example indent. if (!DryRun) Token->adaptStartOfLine(0, Whitespaces); unsigned ContentIndent = 0; unsigned Penalty = 0; LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column " << StartColumn << ".\n"); for (unsigned LineIndex = 0, EndIndex = Token->getLineCount(); LineIndex != EndIndex; ++LineIndex) { LLVM_DEBUG(llvm::dbgs() << " Line: " << LineIndex << " (Reflow: " << Reflow << ")\n"); NewBreakBefore = false; // If we did reflow the previous line, we'll try reflowing again. Otherwise // we'll start reflowing if the current line is broken or whitespace is // compressed. bool TryReflow = Reflow; // Break the current token until we can fit the rest of the line. while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) { LLVM_DEBUG(llvm::dbgs() << " Over limit, need: " << (ContentStartColumn + RemainingTokenColumns) << ", space: " << ColumnLimit << ", reflown prefix: " << ContentStartColumn << ", offset in line: " << TailOffset << "\n"); // If the current token doesn't fit, find the latest possible split in the // current line so that breaking at it will be under the column limit. // FIXME: Use the earliest possible split while reflowing to correctly // compress whitespace within a line. BreakableToken::Split Split = Token->getSplit(LineIndex, TailOffset, ColumnLimit, ContentStartColumn, CommentPragmasRegex); if (Split.first == StringRef::npos) { // No break opportunity - update the penalty and continue with the next // logical line. if (LineIndex < EndIndex - 1) // The last line's penalty is handled in addNextStateToQueue() or when // calling replaceWhitespaceAfterLastLine below. Penalty += Style.PenaltyExcessCharacter * (ContentStartColumn + RemainingTokenColumns - ColumnLimit); LLVM_DEBUG(llvm::dbgs() << " No break opportunity.\n"); break; } assert(Split.first != 0); if (Token->supportsReflow()) { // Check whether the next natural split point after the current one can // still fit the line, either because we can compress away whitespace, // or because the penalty the excess characters introduce is lower than // the break penalty. // We only do this for tokens that support reflowing, and thus allow us // to change the whitespace arbitrarily (e.g. comments). // Other tokens, like string literals, can be broken on arbitrary // positions. // First, compute the columns from TailOffset to the next possible split // position. // For example: // ColumnLimit: | // // Some text that breaks // ^ tail offset // ^-- split // ^-------- to split columns // ^--- next split // ^--------------- to next split columns unsigned ToSplitColumns = Token->getRangeLength( LineIndex, TailOffset, Split.first, ContentStartColumn); LLVM_DEBUG(llvm::dbgs() << " ToSplit: " << ToSplitColumns << "\n"); BreakableToken::Split NextSplit = Token->getSplit( LineIndex, TailOffset + Split.first + Split.second, ColumnLimit, ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex); // Compute the columns necessary to fit the next non-breakable sequence // into the current line. unsigned ToNextSplitColumns = 0; if (NextSplit.first == StringRef::npos) { ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset, ContentStartColumn); } else { ToNextSplitColumns = Token->getRangeLength( LineIndex, TailOffset, Split.first + Split.second + NextSplit.first, ContentStartColumn); } // Compress the whitespace between the break and the start of the next // unbreakable sequence. ToNextSplitColumns = Token->getLengthAfterCompression(ToNextSplitColumns, Split); LLVM_DEBUG(llvm::dbgs() << " ContentStartColumn: " << ContentStartColumn << "\n"); LLVM_DEBUG(llvm::dbgs() << " ToNextSplit: " << ToNextSplitColumns << "\n"); // If the whitespace compression makes us fit, continue on the current // line. bool ContinueOnLine = ContentStartColumn + ToNextSplitColumns <= ColumnLimit; unsigned ExcessCharactersPenalty = 0; if (!ContinueOnLine && !Strict) { // Similarly, if the excess characters' penalty is lower than the // penalty of introducing a new break, continue on the current line. ExcessCharactersPenalty = (ContentStartColumn + ToNextSplitColumns - ColumnLimit) * Style.PenaltyExcessCharacter; LLVM_DEBUG(llvm::dbgs() << " Penalty excess: " << ExcessCharactersPenalty << "\n break : " << NewBreakPenalty << "\n"); if (ExcessCharactersPenalty < NewBreakPenalty) { Exceeded = true; ContinueOnLine = true; } } if (ContinueOnLine) { LLVM_DEBUG(llvm::dbgs() << " Continuing on line...\n"); // The current line fits after compressing the whitespace - reflow // the next line into it if possible. TryReflow = true; if (!DryRun) Token->compressWhitespace(LineIndex, TailOffset, Split, Whitespaces); // When we continue on the same line, leave one space between content. ContentStartColumn += ToSplitColumns + 1; Penalty += ExcessCharactersPenalty; TailOffset += Split.first + Split.second; RemainingTokenColumns = Token->getRemainingLength( LineIndex, TailOffset, ContentStartColumn); continue; } } LLVM_DEBUG(llvm::dbgs() << " Breaking...\n"); // Update the ContentIndent only if the current line was not reflown with // the previous line, since in that case the previous line should still // determine the ContentIndent. Also never intent the last line. if (!Reflow) ContentIndent = Token->getContentIndent(LineIndex); LLVM_DEBUG(llvm::dbgs() << " ContentIndent: " << ContentIndent << "\n"); ContentStartColumn = ContentIndent + Token->getContentStartColumn( LineIndex, /*Break=*/true); unsigned NewRemainingTokenColumns = Token->getRemainingLength( LineIndex, TailOffset + Split.first + Split.second, ContentStartColumn); if (NewRemainingTokenColumns == 0) { // No content to indent. ContentIndent = 0; ContentStartColumn = Token->getContentStartColumn(LineIndex, /*Break=*/true); NewRemainingTokenColumns = Token->getRemainingLength( LineIndex, TailOffset + Split.first + Split.second, ContentStartColumn); } // When breaking before a tab character, it may be moved by a few columns, // but will still be expanded to the next tab stop, so we don't save any // columns. if (NewRemainingTokenColumns == RemainingTokenColumns) { // FIXME: Do we need to adjust the penalty? break; } assert(NewRemainingTokenColumns < RemainingTokenColumns); LLVM_DEBUG(llvm::dbgs() << " Breaking at: " << TailOffset + Split.first << ", " << Split.second << "\n"); if (!DryRun) Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent, Whitespaces); Penalty += NewBreakPenalty; TailOffset += Split.first + Split.second; RemainingTokenColumns = NewRemainingTokenColumns; BreakInserted = true; NewBreakBefore = true; } // In case there's another line, prepare the state for the start of the next // line. if (LineIndex + 1 != EndIndex) { unsigned NextLineIndex = LineIndex + 1; if (NewBreakBefore) // After breaking a line, try to reflow the next line into the current // one once RemainingTokenColumns fits. TryReflow = true; if (TryReflow) { // We decided that we want to try reflowing the next line into the // current one. // We will now adjust the state as if the reflow is successful (in // preparation for the next line), and see whether that works. If we // decide that we cannot reflow, we will later reset the state to the // start of the next line. Reflow = false; // As we did not continue breaking the line, RemainingTokenColumns is // known to fit after ContentStartColumn. Adapt ContentStartColumn to // the position at which we want to format the next line if we do // actually reflow. // When we reflow, we need to add a space between the end of the current // line and the next line's start column. ContentStartColumn += RemainingTokenColumns + 1; // Get the split that we need to reflow next logical line into the end // of the current one; the split will include any leading whitespace of // the next logical line. BreakableToken::Split SplitBeforeNext = Token->getReflowSplit(NextLineIndex, CommentPragmasRegex); LLVM_DEBUG(llvm::dbgs() << " Size of reflown text: " << ContentStartColumn << "\n Potential reflow split: "); if (SplitBeforeNext.first != StringRef::npos) { LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", " << SplitBeforeNext.second << "\n"); TailOffset = SplitBeforeNext.first + SplitBeforeNext.second; // If the rest of the next line fits into the current line below the // column limit, we can safely reflow. RemainingTokenColumns = Token->getRemainingLength( NextLineIndex, TailOffset, ContentStartColumn); Reflow = true; if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) { LLVM_DEBUG(llvm::dbgs() << " Over limit after reflow, need: " << (ContentStartColumn + RemainingTokenColumns) << ", space: " << ColumnLimit << ", reflown prefix: " << ContentStartColumn << ", offset in line: " << TailOffset << "\n"); // If the whole next line does not fit, try to find a point in // the next line at which we can break so that attaching the part // of the next line to that break point onto the current line is // below the column limit. BreakableToken::Split Split = Token->getSplit(NextLineIndex, TailOffset, ColumnLimit, ContentStartColumn, CommentPragmasRegex); if (Split.first == StringRef::npos) { LLVM_DEBUG(llvm::dbgs() << " Did not find later break\n"); Reflow = false; } else { // Check whether the first split point gets us below the column // limit. Note that we will execute this split below as part of // the normal token breaking and reflow logic within the line. unsigned ToSplitColumns = Token->getRangeLength( NextLineIndex, TailOffset, Split.first, ContentStartColumn); if (ContentStartColumn + ToSplitColumns > ColumnLimit) { LLVM_DEBUG(llvm::dbgs() << " Next split protrudes, need: " << (ContentStartColumn + ToSplitColumns) << ", space: " << ColumnLimit); unsigned ExcessCharactersPenalty = (ContentStartColumn + ToSplitColumns - ColumnLimit) * Style.PenaltyExcessCharacter; if (NewBreakPenalty < ExcessCharactersPenalty) { Reflow = false; } } } } } else { LLVM_DEBUG(llvm::dbgs() << "not found.\n"); } } if (!Reflow) { // If we didn't reflow into the next line, the only space to consider is // the next logical line. Reset our state to match the start of the next // line. TailOffset = 0; ContentStartColumn = Token->getContentStartColumn(NextLineIndex, /*Break=*/false); RemainingTokenColumns = Token->getRemainingLength( NextLineIndex, TailOffset, ContentStartColumn); // Adapt the start of the token, for example indent. if (!DryRun) Token->adaptStartOfLine(NextLineIndex, Whitespaces); } else { // If we found a reflow split and have added a new break before the next // line, we are going to remove the line break at the start of the next // logical line. For example, here we'll add a new line break after // 'text', and subsequently delete the line break between 'that' and // 'reflows'. // // some text that // // reflows // -> // // some text // // that reflows // When adding the line break, we also added the penalty for it, so we // need to subtract that penalty again when we remove the line break due // to reflowing. if (NewBreakBefore) { assert(Penalty >= NewBreakPenalty); Penalty -= NewBreakPenalty; } if (!DryRun) Token->reflow(NextLineIndex, Whitespaces); } } } BreakableToken::Split SplitAfterLastLine = Token->getSplitAfterLastLine(TailOffset); if (SplitAfterLastLine.first != StringRef::npos) { LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n"); // We add the last line's penalty here, since that line is going to be split // now. Penalty += Style.PenaltyExcessCharacter * (ContentStartColumn + RemainingTokenColumns - ColumnLimit); if (!DryRun) Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine, Whitespaces); ContentStartColumn = Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true); RemainingTokenColumns = Token->getRemainingLength( Token->getLineCount() - 1, TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second, ContentStartColumn); } State.Column = ContentStartColumn + RemainingTokenColumns - Current.UnbreakableTailLength; if (BreakInserted) { // If we break the token inside a parameter list, we need to break before // the next parameter on all levels, so that the next parameter is clearly // visible. Line comments already introduce a break. if (Current.isNot(TT_LineComment)) { for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) State.Stack[i].BreakBeforeParameter = true; } if (Current.is(TT_BlockComment)) State.NoContinuation = true; State.Stack.back().LastSpace = StartColumn; } Token->updateNextToken(State); return {Penalty, Exceeded}; } unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const { // In preprocessor directives reserve two chars for trailing " \" return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0); } bool ContinuationIndenter::nextIsMultilineString(const LineState &State) { const FormatToken &Current = *State.NextToken; if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral)) return false; // We never consider raw string literals "multiline" for the purpose of // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased // (see TokenAnnotator::mustBreakBefore(). if (Current.TokenText.startswith("R\"")) return false; if (Current.IsMultiline) return true; if (Current.getNextNonComment() && Current.getNextNonComment()->isStringLiteral()) return true; // Implicit concatenation. if (Style.ColumnLimit != 0 && Style.BreakStringLiterals && State.Column + Current.ColumnWidth + Current.UnbreakableTailLength > Style.ColumnLimit) return true; // String will be split. return false; } } // namespace format } // namespace clang