| //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// \brief This file implements the continuation indenter. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "format-formatter" |
| |
| #include "BreakableToken.h" |
| #include "ContinuationIndenter.h" |
| #include "WhitespaceManager.h" |
| #include "clang/Basic/OperatorPrecedence.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Format/Format.h" |
| #include "llvm/Support/Debug.h" |
| #include <string> |
| |
| namespace clang { |
| namespace format { |
| |
| // Returns the length of everything up to the first possible line break after |
| // the ), ], } or > matching \c Tok. |
| static unsigned getLengthToMatchingParen(const FormatToken &Tok) { |
| if (Tok.MatchingParen == NULL) |
| return 0; |
| FormatToken *End = Tok.MatchingParen; |
| while (End->Next && !End->Next->CanBreakBefore) { |
| End = End->Next; |
| } |
| return End->TotalLength - Tok.TotalLength + 1; |
| } |
| |
| // 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.Type == TT_CtorInitializerComma && |
| Style.BreakConstructorInitializersBeforeComma) |
| return true; |
| return Previous.is(tok::comma) && !Current.isTrailingComment() && |
| (Previous.Type != TT_CtorInitializerComma || |
| !Style.BreakConstructorInitializersBeforeComma); |
| } |
| |
| ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style, |
| SourceManager &SourceMgr, |
| WhitespaceManager &Whitespaces, |
| encoding::Encoding Encoding, |
| bool BinPackInconclusiveFunctions) |
| : Style(Style), SourceMgr(SourceMgr), Whitespaces(Whitespaces), |
| Encoding(Encoding), |
| BinPackInconclusiveFunctions(BinPackInconclusiveFunctions) {} |
| |
| LineState ContinuationIndenter::getInitialState(unsigned FirstIndent, |
| const AnnotatedLine *Line, |
| bool DryRun) { |
| LineState State; |
| State.FirstIndent = FirstIndent; |
| State.Column = FirstIndent; |
| State.Line = Line; |
| State.NextToken = Line->First; |
| State.Stack.push_back(ParenState(FirstIndent, Line->Level, FirstIndent, |
| /*AvoidBinPacking=*/false, |
| /*NoLineBreak=*/false)); |
| State.LineContainsContinuedForLoopSection = false; |
| State.ParenLevel = 0; |
| State.StartOfStringLiteral = 0; |
| State.StartOfLineLevel = State.ParenLevel; |
| State.LowestLevelOnLine = State.ParenLevel; |
| State.IgnoreStackForComparison = 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 && |
| !(Current.is(tok::r_brace) && State.Stack.back().BreakBeforeClosingBrace)) |
| 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.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() && State.LowestLevelOnLine < State.StartOfLineLevel) |
| return false; |
| if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder) |
| 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.Type == TT_InlineASMColon) |
| return true; |
| if ((!Style.Cpp11BracedListStyle || |
| (Current.MatchingParen && |
| Current.MatchingParen->BlockKind == BK_Block)) && |
| Current.is(tok::r_brace) && State.Stack.back().BreakBeforeClosingBrace) |
| return true; |
| if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection) |
| return true; |
| if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) || |
| Current.is(tok::question) || |
| (Current.Type == TT_ConditionalExpr && Previous.isNot(tok::question))) && |
| State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() && |
| !Current.isOneOf(tok::r_paren, tok::r_brace)) |
| return true; |
| if (Style.AlwaysBreakBeforeMultilineStrings && |
| State.Column > State.Stack.back().Indent && // Breaking saves columns. |
| !Previous.isOneOf(tok::kw_return, tok::lessless) && |
| Previous.Type != TT_InlineASMColon && NextIsMultilineString(State)) |
| return true; |
| if (Previous.Type == TT_ObjCDictLiteral && Previous.is(tok::l_brace) && |
| getLengthToMatchingParen(Previous) + State.Column > getColumnLimit(State)) |
| return true; |
| |
| if (!Style.BreakBeforeBinaryOperators) { |
| // 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. |
| // |
| // FIXME: We'll need something similar for styles that break before binary |
| // operators. |
| bool IsComparison = (Previous.getPrecedence() == prec::Relational || |
| Previous.getPrecedence() == prec::Equality) && |
| Previous.Previous && |
| Previous.Previous->Type != TT_BinaryOperator; // For >>. |
| bool LHSIsBinaryExpr = |
| Previous.Previous && Previous.Previous->EndsBinaryExpression; |
| if (Previous.Type == TT_BinaryOperator && |
| (!IsComparison || LHSIsBinaryExpr) && |
| Current.Type != TT_BinaryOperator && // For >>. |
| !Current.isTrailingComment() && |
| !Previous.isOneOf(tok::lessless, tok::question) && |
| Previous.getPrecedence() != prec::Assignment && |
| State.Stack.back().BreakBeforeParameter) |
| return true; |
| } |
| |
| // Same as above, but for the first "<<" operator. |
| if (Current.is(tok::lessless) && State.Stack.back().BreakBeforeParameter && |
| State.Stack.back().FirstLessLess == 0) |
| return true; |
| |
| // FIXME: Comparing LongestObjCSelectorName to 0 is a hacky way of finding |
| // out whether it is the first parameter. Clean this up. |
| if (Current.Type == TT_ObjCSelectorName && |
| Current.LongestObjCSelectorName == 0 && |
| State.Stack.back().BreakBeforeParameter) |
| return true; |
| if ((Current.Type == TT_CtorInitializerColon || |
| (Previous.ClosesTemplateDeclaration && State.ParenLevel == 0 && |
| !Current.isTrailingComment()))) |
| return true; |
| |
| if ((Current.Type == TT_StartOfName || Current.is(tok::kw_operator)) && |
| State.Line->MightBeFunctionDecl && |
| State.Stack.back().BreakBeforeParameter && State.ParenLevel == 0) |
| return true; |
| if (startsSegmentOfBuilderTypeCall(Current) && |
| (State.Stack.back().CallContinuation != 0 || |
| (State.Stack.back().BreakBeforeParameter && |
| State.Stack.back().ContainsUnwrappedBuilder))) |
| return true; |
| return false; |
| } |
| |
| unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline, |
| bool DryRun, |
| unsigned ExtraSpaces) { |
| const FormatToken &Current = *State.NextToken; |
| |
| if (State.Stack.size() == 0 || Current.Type == TT_ImplicitStringLiteral) { |
| // FIXME: Is this correct? |
| int WhitespaceLength = SourceMgr.getSpellingColumnNumber( |
| State.NextToken->WhitespaceRange.getEnd()) - |
| SourceMgr.getSpellingColumnNumber( |
| State.NextToken->WhitespaceRange.getBegin()); |
| State.Column += WhitespaceLength + State.NextToken->ColumnWidth; |
| State.NextToken = State.NextToken->Next; |
| 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) || State.ParenLevel == 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; |
| |
| if (!DryRun) |
| Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, /*IndentLevel=*/0, |
| Spaces, State.Column + Spaces); |
| |
| if (Current.Type == TT_ObjCSelectorName && State.Stack.back().ColonPos == 0) { |
| if (State.Stack.back().Indent + Current.LongestObjCSelectorName > |
| State.Column + Spaces + Current.ColumnWidth) |
| State.Stack.back().ColonPos = |
| State.Stack.back().Indent + Current.LongestObjCSelectorName; |
| else |
| State.Stack.back().ColonPos = State.Column + Spaces + Current.ColumnWidth; |
| } |
| |
| if (Previous.opensScope() && Previous.Type != TT_ObjCMethodExpr && |
| Current.Type != TT_LineComment) |
| State.Stack.back().Indent = State.Column + Spaces; |
| if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style)) |
| State.Stack.back().NoLineBreak = true; |
| if (startsSegmentOfBuilderTypeCall(Current)) |
| State.Stack.back().ContainsUnwrappedBuilder = true; |
| |
| State.Column += Spaces; |
| if (Current.is(tok::l_paren) && Previous.isOneOf(tok::kw_if, tok::kw_for)) |
| // 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 + 1; // 1 is length of "(". |
| else if (Previous.is(tok::comma)) |
| State.Stack.back().LastSpace = State.Column; |
| else if ((Previous.Type == TT_BinaryOperator || |
| Previous.Type == TT_ConditionalExpr || |
| Previous.Type == TT_UnaryOperator || |
| Previous.Type == TT_CtorInitializerColon) && |
| (Previous.getPrecedence() != prec::Assignment || |
| Current.StartsBinaryExpression)) |
| // Always 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. |
| State.Stack.back().LastSpace = State.Column; |
| else if (Previous.Type == 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[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; |
| // 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; |
| // Extra penalty that needs to be added because of the way certain line |
| // breaks are chosen. |
| unsigned Penalty = 0; |
| |
| const FormatToken *PreviousNonComment = |
| State.NextToken->getPreviousNonComment(); |
| // The first line break on any ParenLevel 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. |
| if (Current.is(tok::lessless) && State.Stack.back().FirstLessLess == 0 && |
| State.Column <= Style.ColumnLimit / 2) |
| Penalty += Style.PenaltyBreakFirstLessLess; |
| |
| if (Current.is(tok::l_brace) && Current.BlockKind == BK_Block) { |
| State.Column = State.FirstIndent; |
| } else if (Current.is(tok::r_brace)) { |
| if (Current.MatchingParen && |
| (Current.MatchingParen->BlockKind == BK_BracedInit || |
| !Current.MatchingParen->Children.empty())) |
| State.Column = State.Stack[State.Stack.size() - 2].LastSpace; |
| else |
| State.Column = State.FirstIndent; |
| } else if (Current.is(tok::string_literal) && |
| State.StartOfStringLiteral != 0) { |
| State.Column = State.StartOfStringLiteral; |
| State.Stack.back().BreakBeforeParameter = true; |
| } else if (Current.is(tok::lessless) && |
| State.Stack.back().FirstLessLess != 0) { |
| State.Column = State.Stack.back().FirstLessLess; |
| } else if (Current.isMemberAccess()) { |
| if (State.Stack.back().CallContinuation == 0) { |
| State.Column = ContinuationIndent; |
| State.Stack.back().CallContinuation = State.Column; |
| } else { |
| State.Column = State.Stack.back().CallContinuation; |
| } |
| } else if (Current.Type == TT_ConditionalExpr) { |
| State.Column = State.Stack.back().QuestionColumn; |
| } else if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0) { |
| State.Column = State.Stack.back().VariablePos; |
| } else if ((PreviousNonComment && |
| PreviousNonComment->ClosesTemplateDeclaration) || |
| ((Current.Type == TT_StartOfName || |
| Current.is(tok::kw_operator)) && |
| State.ParenLevel == 0 && |
| (!Style.IndentFunctionDeclarationAfterType || |
| State.Line->StartsDefinition))) { |
| State.Column = State.Stack.back().Indent; |
| } else if (Current.Type == TT_ObjCSelectorName) { |
| if (State.Stack.back().ColonPos > Current.ColumnWidth) { |
| State.Column = State.Stack.back().ColonPos - Current.ColumnWidth; |
| } else { |
| State.Column = State.Stack.back().Indent; |
| State.Stack.back().ColonPos = State.Column + Current.ColumnWidth; |
| } |
| } else if (Current.is(tok::l_square) && Current.Type != TT_ObjCMethodExpr && |
| Current.Type != TT_LambdaLSquare) { |
| if (State.Stack.back().StartOfArraySubscripts != 0) |
| State.Column = State.Stack.back().StartOfArraySubscripts; |
| else |
| State.Column = ContinuationIndent; |
| } else if (Current.Type == TT_StartOfName || |
| Previous.isOneOf(tok::coloncolon, tok::equal) || |
| Previous.Type == TT_ObjCMethodExpr) { |
| State.Column = ContinuationIndent; |
| } else if (Current.Type == TT_CtorInitializerColon) { |
| State.Column = State.FirstIndent + Style.ConstructorInitializerIndentWidth; |
| } else if (Current.Type == TT_CtorInitializerComma) { |
| State.Column = State.Stack.back().Indent; |
| } else { |
| State.Column = State.Stack.back().Indent; |
| // Ensure that we fall back to the continuation indent width instead of just |
| // flushing continuations left. |
| if (State.Column == State.FirstIndent) |
| State.Column += Style.ContinuationIndentWidth; |
| } |
| |
| if (Current.is(tok::question)) |
| State.Stack.back().BreakBeforeParameter = true; |
| if ((Previous.isOneOf(tok::comma, tok::semi) && |
| !State.Stack.back().AvoidBinPacking) || |
| Previous.Type == TT_BinaryOperator) |
| State.Stack.back().BreakBeforeParameter = false; |
| if (Previous.Type == TT_TemplateCloser && State.ParenLevel == 0) |
| State.Stack.back().BreakBeforeParameter = false; |
| |
| if (!DryRun) { |
| unsigned Newlines = 1; |
| if (Current.is(tok::comment)) |
| Newlines = std::max(Newlines, std::min(Current.NewlinesBefore, |
| Style.MaxEmptyLinesToKeep + 1)); |
| Whitespaces.replaceWhitespace(Current, Newlines, |
| State.Stack.back().IndentLevel, State.Column, |
| State.Column, State.Line->InPPDirective); |
| } |
| |
| if (!Current.isTrailingComment()) |
| State.Stack.back().LastSpace = State.Column; |
| if (Current.isMemberAccess()) |
| State.Stack.back().LastSpace += Current.ColumnWidth; |
| State.StartOfLineLevel = State.ParenLevel; |
| State.LowestLevelOnLine = State.ParenLevel; |
| |
| // Any break on this level means that the parent level has been broken |
| // and we need to avoid bin packing there. |
| for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i) { |
| State.Stack[i].BreakBeforeParameter = true; |
| } |
| const FormatToken *TokenBefore = Current.getPreviousNonComment(); |
| if (TokenBefore && !TokenBefore->isOneOf(tok::comma, tok::semi) && |
| TokenBefore->Type != TT_TemplateCloser && |
| TokenBefore->Type != TT_BinaryOperator && !TokenBefore->opensScope()) |
| State.Stack.back().BreakBeforeParameter = true; |
| |
| // If we break after {, we should also break before the corresponding }. |
| if (Previous.is(tok::l_brace)) |
| State.Stack.back().BreakBeforeClosingBrace = true; |
| |
| if (State.Stack.back().AvoidBinPacking) { |
| // If we are breaking after '(', '{', '<', this is not bin packing |
| // unless AllowAllParametersOfDeclarationOnNextLine is false. |
| if (!(Previous.isOneOf(tok::l_paren, tok::l_brace) || |
| Previous.Type == TT_BinaryOperator) || |
| (!Style.AllowAllParametersOfDeclarationOnNextLine && |
| State.Line->MustBeDeclaration)) |
| State.Stack.back().BreakBeforeParameter = true; |
| } |
| |
| return Penalty; |
| } |
| |
| unsigned ContinuationIndenter::moveStateToNextToken(LineState &State, |
| bool DryRun, bool Newline) { |
| const FormatToken &Current = *State.NextToken; |
| assert(State.Stack.size()); |
| |
| if (Current.Type == TT_InheritanceColon) |
| State.Stack.back().AvoidBinPacking = true; |
| if (Current.is(tok::lessless) && State.Stack.back().FirstLessLess == 0) |
| State.Stack.back().FirstLessLess = State.Column; |
| if (Current.is(tok::l_square) && Current.Type != TT_LambdaLSquare && |
| State.Stack.back().StartOfArraySubscripts == 0) |
| State.Stack.back().StartOfArraySubscripts = State.Column; |
| if (Current.is(tok::question)) |
| State.Stack.back().QuestionColumn = State.Column; |
| if (!Current.opensScope() && !Current.closesScope()) |
| State.LowestLevelOnLine = |
| std::min(State.LowestLevelOnLine, State.ParenLevel); |
| if (Current.isMemberAccess()) |
| State.Stack.back().StartOfFunctionCall = |
| Current.LastInChainOfCalls ? 0 : State.Column + Current.ColumnWidth; |
| if (Current.Type == TT_CtorInitializerColon) { |
| // Indent 2 from the column, so: |
| // SomeClass::SomeClass() |
| // : First(...), ... |
| // Next(...) |
| // ^ line up here. |
| State.Stack.back().Indent = |
| State.Column + (Style.BreakConstructorInitializersBeforeComma ? 0 : 2); |
| if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) |
| State.Stack.back().AvoidBinPacking = true; |
| State.Stack.back().BreakBeforeParameter = false; |
| } |
| |
| // In ObjC method declaration we align on the ":" of parameters, but we need |
| // to ensure that we indent parameters on subsequent lines by at least our |
| // continuation indent width. |
| if (Current.Type == TT_ObjCMethodSpecifier) |
| State.Stack.back().Indent += Style.ContinuationIndentWidth; |
| |
| // Insert scopes created by fake parenthesis. |
| const FormatToken *Previous = Current.getPreviousNonComment(); |
| // Don't add extra indentation for the first fake parenthesis after |
| // 'return', assignements or opening <({[. The indentation for these cases |
| // is special cased. |
| bool SkipFirstExtraIndent = |
| (Previous && (Previous->opensScope() || Previous->is(tok::kw_return) || |
| Previous->getPrecedence() == prec::Assignment)); |
| for (SmallVectorImpl<prec::Level>::const_reverse_iterator |
| I = Current.FakeLParens.rbegin(), |
| E = Current.FakeLParens.rend(); |
| I != E; ++I) { |
| ParenState NewParenState = State.Stack.back(); |
| NewParenState.ContainsLineBreak = false; |
| |
| // Indent from 'LastSpace' unless this the fake parentheses encapsulating a |
| // builder type call after 'return'. If such a call is line-wrapped, we |
| // commonly just want to indent from the start of the line. |
| if (!Previous || Previous->isNot(tok::kw_return) || *I > 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); |
| |
| // 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 && |
| !Style.BreakBeforeBinaryOperators)) |
| NewParenState.Indent += Style.ContinuationIndentWidth; |
| if (Previous && !Previous->opensScope()) |
| NewParenState.BreakBeforeParameter = false; |
| State.Stack.push_back(NewParenState); |
| SkipFirstExtraIndent = false; |
| } |
| |
| // If we encounter an opening (, [, { or <, we add a level to our stacks to |
| // prepare for the following tokens. |
| if (Current.opensScope()) { |
| unsigned NewIndent; |
| unsigned NewIndentLevel = State.Stack.back().IndentLevel; |
| bool AvoidBinPacking; |
| if (Current.is(tok::l_brace)) { |
| if (Current.MatchingParen && Current.BlockKind == BK_Block) { |
| // If this is an l_brace starting a nested block, we pretend (wrt. to |
| // indentation) that we already consumed the corresponding r_brace. |
| // Thus, we remove all ParenStates caused bake fake parentheses that end |
| // at the r_brace. The net effect of this is that we don't indent |
| // relative to the l_brace, if the nested block is the last parameter of |
| // a function. For example, this formats: |
| // |
| // SomeFunction(a, [] { |
| // f(); // break |
| // }); |
| // |
| // instead of: |
| // SomeFunction(a, [] { |
| // f(); // break |
| // }); |
| for (unsigned i = 0; i != Current.MatchingParen->FakeRParens; ++i) |
| State.Stack.pop_back(); |
| NewIndent = State.Stack.back().LastSpace + Style.IndentWidth; |
| ++NewIndentLevel; |
| } else { |
| NewIndent = State.Stack.back().LastSpace; |
| if (Style.Cpp11BracedListStyle) |
| NewIndent += Style.ContinuationIndentWidth; |
| else { |
| NewIndent += Style.IndentWidth; |
| ++NewIndentLevel; |
| } |
| } |
| const FormatToken *NextNoComment = Current.getNextNonComment(); |
| AvoidBinPacking = Current.BlockKind == BK_Block || |
| (NextNoComment && |
| NextNoComment->Type == TT_DesignatedInitializerPeriod); |
| } else { |
| NewIndent = Style.ContinuationIndentWidth + |
| std::max(State.Stack.back().LastSpace, |
| State.Stack.back().StartOfFunctionCall); |
| AvoidBinPacking = !Style.BinPackParameters || |
| (Style.ExperimentalAutoDetectBinPacking && |
| (Current.PackingKind == PPK_OnePerLine || |
| (!BinPackInconclusiveFunctions && |
| Current.PackingKind == PPK_Inconclusive))); |
| } |
| |
| bool NoLineBreak = State.Stack.back().NoLineBreak || |
| (Current.Type == TT_TemplateOpener && |
| State.Stack.back().ContainsUnwrappedBuilder); |
| State.Stack.push_back(ParenState(NewIndent, NewIndentLevel, |
| State.Stack.back().LastSpace, |
| AvoidBinPacking, NoLineBreak)); |
| State.Stack.back().BreakBeforeParameter = Current.BlockKind == BK_Block; |
| ++State.ParenLevel; |
| } |
| |
| // If this '[' opens an ObjC call, determine whether all parameters fit into |
| // one line and put one per line if they don't. |
| if (Current.isOneOf(tok::l_brace, tok::l_square) && |
| (Current.Type == TT_ObjCDictLiteral || |
| Current.Type == TT_ObjCMethodExpr) && |
| Current.MatchingParen != NULL) { |
| if (getLengthToMatchingParen(Current) + State.Column > |
| getColumnLimit(State)) { |
| State.Stack.back().BreakBeforeParameter = true; |
| State.Stack.back().AvoidBinPacking = true; |
| } |
| } |
| |
| // 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) || |
| (Current.is(tok::r_brace) && State.NextToken != State.Line->First) || |
| State.NextToken->Type == TT_TemplateCloser)) { |
| State.Stack.pop_back(); |
| --State.ParenLevel; |
| } |
| 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; |
| } |
| |
| // Remove scopes created by fake parenthesis. |
| if (Current.isNot(tok::r_brace) || |
| (Current.MatchingParen && Current.MatchingParen->BlockKind != BK_Block)) { |
| // Don't remove FakeRParens attached to r_braces that surround nested blocks |
| // as they will have been removed early (see above). |
| for (unsigned i = 0, e = Current.FakeRParens; i != e; ++i) { |
| unsigned VariablePos = State.Stack.back().VariablePos; |
| State.Stack.pop_back(); |
| State.Stack.back().VariablePos = VariablePos; |
| } |
| } |
| |
| if (Current.is(tok::string_literal) && State.StartOfStringLiteral == 0) { |
| State.StartOfStringLiteral = State.Column; |
| } else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash, |
| tok::string_literal)) { |
| State.StartOfStringLiteral = 0; |
| } |
| |
| State.Column += Current.ColumnWidth; |
| State.NextToken = State.NextToken->Next; |
| unsigned Penalty = breakProtrudingToken(Current, State, DryRun); |
| if (State.Column > getColumnLimit(State)) { |
| unsigned ExcessCharacters = State.Column - getColumnLimit(State); |
| Penalty += Style.PenaltyExcessCharacter * ExcessCharacters; |
| } |
| |
| // 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->format(State, this, DryRun); |
| |
| return Penalty; |
| } |
| |
| 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; |
| } |
| |
| static bool getRawStringLiteralPrefixPostfix(StringRef Text, |
| StringRef &Prefix, |
| StringRef &Postfix) { |
| if (Text.startswith(Prefix = "R\"") || Text.startswith(Prefix = "uR\"") || |
| Text.startswith(Prefix = "UR\"") || Text.startswith(Prefix = "u8R\"") || |
| Text.startswith(Prefix = "LR\"")) { |
| size_t ParenPos = Text.find('('); |
| if (ParenPos != StringRef::npos) { |
| StringRef Delimiter = |
| Text.substr(Prefix.size(), ParenPos - Prefix.size()); |
| Prefix = Text.substr(0, ParenPos + 1); |
| Postfix = Text.substr(Text.size() - 2 - Delimiter.size()); |
| return Postfix.front() == ')' && Postfix.back() == '"' && |
| Postfix.substr(1).startswith(Delimiter); |
| } |
| } |
| return false; |
| } |
| |
| unsigned ContinuationIndenter::breakProtrudingToken(const FormatToken &Current, |
| LineState &State, |
| bool DryRun) { |
| // Don't break multi-line tokens other than block comments. Instead, just |
| // update the state. |
| if (Current.Type != TT_BlockComment && Current.IsMultiline) |
| return addMultilineToken(Current, State); |
| |
| if (!Current.isOneOf(tok::string_literal, tok::wide_string_literal, |
| tok::utf8_string_literal, tok::utf16_string_literal, |
| tok::utf32_string_literal, tok::comment)) |
| return 0; |
| |
| llvm::OwningPtr<BreakableToken> Token; |
| unsigned StartColumn = State.Column - Current.ColumnWidth; |
| |
| if (Current.isOneOf(tok::string_literal, tok::wide_string_literal, |
| tok::utf8_string_literal, tok::utf16_string_literal, |
| tok::utf32_string_literal) && |
| Current.Type != TT_ImplicitStringLiteral) { |
| // 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 0; |
| // 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 0; |
| |
| 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 = "u\"") || |
| Text.startswith(Prefix = "U\"") || Text.startswith(Prefix = "u8\"") || |
| Text.startswith(Prefix = "L\""))) || |
| (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")")) || |
| getRawStringLiteralPrefixPostfix(Text, Prefix, Postfix)) { |
| Token.reset(new BreakableStringLiteral( |
| Current, State.Line->Level, StartColumn, Prefix, Postfix, |
| State.Line->InPPDirective, Encoding, Style)); |
| } else { |
| return 0; |
| } |
| } else if (Current.Type == TT_BlockComment && Current.isTrailingComment()) { |
| Token.reset(new BreakableBlockComment( |
| Current, State.Line->Level, StartColumn, Current.OriginalColumn, |
| !Current.Previous, State.Line->InPPDirective, Encoding, Style)); |
| } else if (Current.Type == TT_LineComment && |
| (Current.Previous == NULL || |
| Current.Previous->Type != TT_ImplicitStringLiteral)) { |
| Token.reset(new BreakableLineComment(Current, State.Line->Level, |
| StartColumn, State.Line->InPPDirective, |
| Encoding, Style)); |
| } else { |
| return 0; |
| } |
| if (Current.UnbreakableTailLength >= getColumnLimit(State)) |
| return 0; |
| |
| unsigned RemainingSpace = |
| getColumnLimit(State) - Current.UnbreakableTailLength; |
| bool BreakInserted = false; |
| unsigned Penalty = 0; |
| unsigned RemainingTokenColumns = 0; |
| for (unsigned LineIndex = 0, EndIndex = Token->getLineCount(); |
| LineIndex != EndIndex; ++LineIndex) { |
| if (!DryRun) |
| Token->replaceWhitespaceBefore(LineIndex, Whitespaces); |
| unsigned TailOffset = 0; |
| RemainingTokenColumns = |
| Token->getLineLengthAfterSplit(LineIndex, TailOffset, StringRef::npos); |
| while (RemainingTokenColumns > RemainingSpace) { |
| BreakableToken::Split Split = |
| Token->getSplit(LineIndex, TailOffset, getColumnLimit(State)); |
| if (Split.first == StringRef::npos) { |
| // The last line's penalty is handled in addNextStateToQueue(). |
| if (LineIndex < EndIndex - 1) |
| Penalty += Style.PenaltyExcessCharacter * |
| (RemainingTokenColumns - RemainingSpace); |
| break; |
| } |
| assert(Split.first != 0); |
| unsigned NewRemainingTokenColumns = Token->getLineLengthAfterSplit( |
| LineIndex, TailOffset + Split.first + Split.second, StringRef::npos); |
| assert(NewRemainingTokenColumns < RemainingTokenColumns); |
| if (!DryRun) |
| Token->insertBreak(LineIndex, TailOffset, Split, Whitespaces); |
| Penalty += Current.SplitPenalty; |
| unsigned ColumnsUsed = |
| Token->getLineLengthAfterSplit(LineIndex, TailOffset, Split.first); |
| if (ColumnsUsed > getColumnLimit(State)) { |
| Penalty += Style.PenaltyExcessCharacter * |
| (ColumnsUsed - getColumnLimit(State)); |
| } |
| TailOffset += Split.first + Split.second; |
| RemainingTokenColumns = NewRemainingTokenColumns; |
| BreakInserted = true; |
| } |
| } |
| |
| State.Column = RemainingTokenColumns; |
| |
| 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.Type != TT_LineComment) { |
| for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) |
| State.Stack[i].BreakBeforeParameter = true; |
| } |
| |
| Penalty += Current.is(tok::string_literal) ? Style.PenaltyBreakString |
| : Style.PenaltyBreakComment; |
| |
| State.Stack.back().LastSpace = StartColumn; |
| } |
| return Penalty; |
| } |
| |
| 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.is(tok::string_literal)) |
| return false; |
| // We never consider raw string literals "multiline" for the purpose of |
| // AlwaysBreakBeforeMultilineStrings implementation. |
| if (Current.TokenText.startswith("R\"")) |
| return false; |
| if (Current.IsMultiline) |
| return true; |
| if (Current.getNextNonComment() && |
| Current.getNextNonComment()->is(tok::string_literal)) |
| return true; // Implicit concatenation. |
| if (State.Column + Current.ColumnWidth + Current.UnbreakableTailLength > |
| Style.ColumnLimit) |
| return true; // String will be split. |
| return false; |
| } |
| |
| } // namespace format |
| } // namespace clang |