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//===--- 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
/// 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<ParenState> &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<StringRef> 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"<delimiter>(' 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<FormatStyle> 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<FormatStyle>
RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
auto It = DelimiterStyle.find(Delimiter);
if (It == DelimiterStyle.end())
return None;
return It->second;
}
llvm::Optional<FormatStyle>
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))
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) &&
!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.
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 '(', '{', '<', this is not bin packing
// unless AllowAllParametersOfDeclarationOnNextLine is false or this is a
// dict/object literal.
if (!Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
(!Style.AllowAllParametersOfDeclarationOnNextLine &&
State.Line->MustBeDeclaration) ||
Previous.is(TT_DictLiteral))
State.Stack.back().BreakBeforeParameter = true;
}
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 or
// opening brace. This allows indentations such as:
// foo(
// a,
// );
// function foo(
// a,
// ) {
// code(); //
// }
if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
(!Current.Next || Current.Next->isOneOf(tok::semi, 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->isNot(tok::r_brace))
// 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 = 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) {
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;
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);
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<prec::Level>::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) {
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';
unsigned NextStartColumn =
ContentStartsOnNewline
? State.Stack.back().NestedBlockIndent + 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
: State.Stack.back().NestedBlockIndent;
std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
/*Status=*/nullptr);
auto NewCode = applyAllReplacements(RawText, Fixes.first);
tooling::Replacements NoFixes;
if (!NewCode) {
State.Column += Current.ColumnWidth;
return 0;
}
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;
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) {
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);
} 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<templates>(' 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<FormatStyle>
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<BreakableToken> 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 Java and JS, 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.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<BreakableStringLiteral>(
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<BreakableBlockComment>(
Current, StartColumn, Current.OriginalColumn, !Current.Previous,
State.Line->InPPDirective, Encoding, Style);
} 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<BreakableLineCommentSection>(
Current, StartColumn, Current.OriginalColumn, !Current.Previous,
/*InPPDirective=*/false, Encoding, Style);
}
return nullptr;
}
std::pair<unsigned, bool>
ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
LineState &State, bool AllowBreak,
bool DryRun, bool Strict) {
std::unique_ptr<const BreakableToken> 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().
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");
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