1 //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This file implements the continuation indenter.
13 //===----------------------------------------------------------------------===//
15 #include "ContinuationIndenter.h"
16 #include "BreakableToken.h"
17 #include "FormatInternal.h"
18 #include "WhitespaceManager.h"
19 #include "clang/Basic/OperatorPrecedence.h"
20 #include "clang/Basic/SourceManager.h"
21 #include "clang/Format/Format.h"
22 #include "llvm/Support/Debug.h"
24 #define DEBUG_TYPE "format-indenter"
29 // Returns true if a TT_SelectorName should be indented when wrapped,
31 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
33 return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl;
36 // Returns the length of everything up to the first possible line break after
37 // the ), ], } or > matching \c Tok.
38 static unsigned getLengthToMatchingParen(const FormatToken &Tok,
39 const std::vector<ParenState> &Stack) {
40 // Normally whether or not a break before T is possible is calculated and
41 // stored in T.CanBreakBefore. Braces, array initializers and text proto
42 // messages like `key: < ... >` are an exception: a break is possible
43 // before a closing brace R if a break was inserted after the corresponding
44 // opening brace. The information about whether or not a break is needed
45 // before a closing brace R is stored in the ParenState field
46 // S.BreakBeforeClosingBrace where S is the state that R closes.
48 // In order to decide whether there can be a break before encountered right
49 // braces, this implementation iterates over the sequence of tokens and over
50 // the paren stack in lockstep, keeping track of the stack level which visited
51 // right braces correspond to in MatchingStackIndex.
53 // For example, consider:
59 // ^ where we call this method with this token.
60 // The paren stack at this point contains 3 brace levels:
61 // 0. { at line 1, BreakBeforeClosingBrace: true
62 // 1. first { at line 4, BreakBeforeClosingBrace: false
63 // 2. second { at line 4, BreakBeforeClosingBrace: false,
64 // where there might be fake parens levels in-between these levels.
65 // The algorithm will start at the first } on line 4, which is the matching
66 // brace of the initial left brace and at level 2 of the stack. Then,
67 // examining BreakBeforeClosingBrace: false at level 2, it will continue to
68 // the second } on line 4, and will traverse the stack downwards until it
69 // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace:
70 // false at level 1, it will continue to the third } on line 4 and will
71 // traverse the stack downwards until it finds the matching { on level 0.
72 // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm
73 // will stop and will use the second } on line 4 to determine the length to
74 // return, as in this example the range will include the tokens: {3}}
76 // The algorithm will only traverse the stack if it encounters braces, array
77 // initializer squares or text proto angle brackets.
78 if (!Tok.MatchingParen)
80 FormatToken *End = Tok.MatchingParen;
81 // Maintains a stack level corresponding to the current End token.
82 int MatchingStackIndex = Stack.size() - 1;
83 // Traverses the stack downwards, looking for the level to which LBrace
84 // corresponds. Returns either a pointer to the matching level or nullptr if
85 // LParen is not found in the initial portion of the stack up to
86 // MatchingStackIndex.
87 auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * {
88 while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace)
90 return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr;
92 for (; End->Next; End = End->Next) {
93 if (End->Next->CanBreakBefore)
95 if (!End->Next->closesScope())
97 if (End->Next->MatchingParen &&
98 End->Next->MatchingParen->isOneOf(
99 tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) {
100 const ParenState *State = FindParenState(End->Next->MatchingParen);
101 if (State && State->BreakBeforeClosingBrace)
105 return End->TotalLength - Tok.TotalLength + 1;
108 static unsigned getLengthToNextOperator(const FormatToken &Tok) {
109 if (!Tok.NextOperator)
111 return Tok.NextOperator->TotalLength - Tok.TotalLength;
114 // Returns \c true if \c Tok is the "." or "->" of a call and starts the next
115 // segment of a builder type call.
116 static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) {
117 return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope();
120 // Returns \c true if \c Current starts a new parameter.
121 static bool startsNextParameter(const FormatToken &Current,
122 const FormatStyle &Style) {
123 const FormatToken &Previous = *Current.Previous;
124 if (Current.is(TT_CtorInitializerComma) &&
125 Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma)
127 if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName))
129 return Previous.is(tok::comma) && !Current.isTrailingComment() &&
130 ((Previous.isNot(TT_CtorInitializerComma) ||
131 Style.BreakConstructorInitializers !=
132 FormatStyle::BCIS_BeforeComma) &&
133 (Previous.isNot(TT_InheritanceComma) ||
134 Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma));
137 static bool opensProtoMessageField(const FormatToken &LessTok,
138 const FormatStyle &Style) {
139 if (LessTok.isNot(tok::less))
141 return Style.Language == FormatStyle::LK_TextProto ||
142 (Style.Language == FormatStyle::LK_Proto &&
143 (LessTok.NestingLevel > 0 ||
144 (LessTok.Previous && LessTok.Previous->is(tok::equal))));
147 // Returns the delimiter of a raw string literal, or None if TokenText is not
148 // the text of a raw string literal. The delimiter could be the empty string.
149 // For example, the delimiter of R"deli(cont)deli" is deli.
150 static llvm::Optional<StringRef> getRawStringDelimiter(StringRef TokenText) {
151 if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'.
152 || !TokenText.startswith("R\"") || !TokenText.endswith("\""))
155 // A raw string starts with 'R"<delimiter>(' and delimiter is ascii and has
156 // size at most 16 by the standard, so the first '(' must be among the first
158 size_t LParenPos = TokenText.substr(0, 19).find_first_of('(');
159 if (LParenPos == StringRef::npos)
161 StringRef Delimiter = TokenText.substr(2, LParenPos - 2);
163 // Check that the string ends in ')Delimiter"'.
164 size_t RParenPos = TokenText.size() - Delimiter.size() - 2;
165 if (TokenText[RParenPos] != ')')
167 if (!TokenText.substr(RParenPos + 1).startswith(Delimiter))
172 // Returns the canonical delimiter for \p Language, or the empty string if no
173 // canonical delimiter is specified.
175 getCanonicalRawStringDelimiter(const FormatStyle &Style,
176 FormatStyle::LanguageKind Language) {
177 for (const auto &Format : Style.RawStringFormats) {
178 if (Format.Language == Language)
179 return StringRef(Format.CanonicalDelimiter);
184 RawStringFormatStyleManager::RawStringFormatStyleManager(
185 const FormatStyle &CodeStyle) {
186 for (const auto &RawStringFormat : CodeStyle.RawStringFormats) {
187 llvm::Optional<FormatStyle> LanguageStyle =
188 CodeStyle.GetLanguageStyle(RawStringFormat.Language);
189 if (!LanguageStyle) {
190 FormatStyle PredefinedStyle;
191 if (!getPredefinedStyle(RawStringFormat.BasedOnStyle,
192 RawStringFormat.Language, &PredefinedStyle)) {
193 PredefinedStyle = getLLVMStyle();
194 PredefinedStyle.Language = RawStringFormat.Language;
196 LanguageStyle = PredefinedStyle;
198 LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit;
199 for (StringRef Delimiter : RawStringFormat.Delimiters) {
200 DelimiterStyle.insert({Delimiter, *LanguageStyle});
202 for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions) {
203 EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle});
208 llvm::Optional<FormatStyle>
209 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
210 auto It = DelimiterStyle.find(Delimiter);
211 if (It == DelimiterStyle.end())
216 llvm::Optional<FormatStyle>
217 RawStringFormatStyleManager::getEnclosingFunctionStyle(
218 StringRef EnclosingFunction) const {
219 auto It = EnclosingFunctionStyle.find(EnclosingFunction);
220 if (It == EnclosingFunctionStyle.end())
225 ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style,
226 const AdditionalKeywords &Keywords,
227 const SourceManager &SourceMgr,
228 WhitespaceManager &Whitespaces,
229 encoding::Encoding Encoding,
230 bool BinPackInconclusiveFunctions)
231 : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr),
232 Whitespaces(Whitespaces), Encoding(Encoding),
233 BinPackInconclusiveFunctions(BinPackInconclusiveFunctions),
234 CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {}
236 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent,
237 unsigned FirstStartColumn,
238 const AnnotatedLine *Line,
241 State.FirstIndent = FirstIndent;
242 if (FirstStartColumn && Line->First->NewlinesBefore == 0)
243 State.Column = FirstStartColumn;
245 State.Column = FirstIndent;
246 // With preprocessor directive indentation, the line starts on column 0
247 // since it's indented after the hash, but FirstIndent is set to the
248 // preprocessor indent.
249 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
250 (Line->Type == LT_PreprocessorDirective ||
251 Line->Type == LT_ImportStatement))
254 State.NextToken = Line->First;
255 State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent,
256 /*AvoidBinPacking=*/false,
257 /*NoLineBreak=*/false));
258 State.LineContainsContinuedForLoopSection = false;
259 State.NoContinuation = false;
260 State.StartOfStringLiteral = 0;
261 State.StartOfLineLevel = 0;
262 State.LowestLevelOnLine = 0;
263 State.IgnoreStackForComparison = false;
265 if (Style.Language == FormatStyle::LK_TextProto) {
266 // We need this in order to deal with the bin packing of text fields at
268 State.Stack.back().AvoidBinPacking = true;
269 State.Stack.back().BreakBeforeParameter = true;
270 State.Stack.back().AlignColons = false;
273 // The first token has already been indented and thus consumed.
274 moveStateToNextToken(State, DryRun, /*Newline=*/false);
278 bool ContinuationIndenter::canBreak(const LineState &State) {
279 const FormatToken &Current = *State.NextToken;
280 const FormatToken &Previous = *Current.Previous;
281 assert(&Previous == Current.Previous);
282 if (!Current.CanBreakBefore && !(State.Stack.back().BreakBeforeClosingBrace &&
283 Current.closesBlockOrBlockTypeList(Style)))
285 // The opening "{" of a braced list has to be on the same line as the first
286 // element if it is nested in another braced init list or function call.
287 if (!Current.MustBreakBefore && Previous.is(tok::l_brace) &&
288 Previous.isNot(TT_DictLiteral) && Previous.BlockKind == BK_BracedInit &&
290 Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma))
292 // This prevents breaks like:
294 // SomeParameter, OtherParameter).DoSomething(
296 // As they hide "DoSomething" and are generally bad for readability.
297 if (Previous.opensScope() && Previous.isNot(tok::l_brace) &&
298 State.LowestLevelOnLine < State.StartOfLineLevel &&
299 State.LowestLevelOnLine < Current.NestingLevel)
301 if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder)
304 // Don't create a 'hanging' indent if there are multiple blocks in a single
306 if (Previous.is(tok::l_brace) && State.Stack.size() > 1 &&
307 State.Stack[State.Stack.size() - 2].NestedBlockInlined &&
308 State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks)
311 // Don't break after very short return types (e.g. "void") as that is often
313 if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) {
314 if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None)
318 // If binary operators are moved to the next line (including commas for some
319 // styles of constructor initializers), that's always ok.
320 if (!Current.isOneOf(TT_BinaryOperator, tok::comma) &&
321 State.Stack.back().NoLineBreakInOperand)
324 if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr))
327 return !State.Stack.back().NoLineBreak;
330 bool ContinuationIndenter::mustBreak(const LineState &State) {
331 const FormatToken &Current = *State.NextToken;
332 const FormatToken &Previous = *Current.Previous;
333 if (Current.MustBreakBefore || Current.is(TT_InlineASMColon))
335 if (State.Stack.back().BreakBeforeClosingBrace &&
336 Current.closesBlockOrBlockTypeList(Style))
338 if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection)
340 if (Style.Language == FormatStyle::LK_ObjC &&
341 Current.ObjCSelectorNameParts > 1 &&
342 Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) {
345 if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
346 (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
348 // FIXME: This is a temporary workaround for the case where clang-format
349 // sets BreakBeforeParameter to avoid bin packing and this creates a
350 // completely unnecessary line break after a template type that isn't
352 (Previous.NestingLevel == 1 || Style.BinPackParameters)) ||
353 (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
354 Previous.isNot(tok::question)) ||
355 (!Style.BreakBeforeTernaryOperators &&
356 Previous.is(TT_ConditionalExpr))) &&
357 State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() &&
358 !Current.isOneOf(tok::r_paren, tok::r_brace))
360 if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) ||
361 (Previous.is(TT_ArrayInitializerLSquare) &&
362 Previous.ParameterCount > 1) ||
363 opensProtoMessageField(Previous, Style)) &&
364 Style.ColumnLimit > 0 &&
365 getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 >
366 getColumnLimit(State))
369 const FormatToken &BreakConstructorInitializersToken =
370 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon
373 if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) &&
374 (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
375 getColumnLimit(State) ||
376 State.Stack.back().BreakBeforeParameter) &&
377 (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All ||
378 Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
379 Style.ColumnLimit != 0))
382 if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) &&
383 State.Line->startsWith(TT_ObjCMethodSpecifier))
385 if (Current.is(TT_SelectorName) && !Previous.is(tok::at) &&
386 State.Stack.back().ObjCSelectorNameFound &&
387 State.Stack.back().BreakBeforeParameter)
390 unsigned NewLineColumn = getNewLineColumn(State);
391 if (Current.isMemberAccess() && Style.ColumnLimit != 0 &&
392 State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit &&
393 (State.Column > NewLineColumn ||
394 Current.NestingLevel < State.StartOfLineLevel))
397 if (startsSegmentOfBuilderTypeCall(Current) &&
398 (State.Stack.back().CallContinuation != 0 ||
399 State.Stack.back().BreakBeforeParameter) &&
400 // JavaScript is treated different here as there is a frequent pattern:
401 // SomeFunction(function() {
404 // FIXME: We should find a more generic solution to this problem.
405 !(State.Column <= NewLineColumn &&
406 Style.Language == FormatStyle::LK_JavaScript))
409 // If the template declaration spans multiple lines, force wrap before the
410 // function/class declaration
411 if (Previous.ClosesTemplateDeclaration &&
412 State.Stack.back().BreakBeforeParameter && Current.CanBreakBefore)
415 if (State.Column <= NewLineColumn)
418 if (Style.AlwaysBreakBeforeMultilineStrings &&
419 (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth ||
420 Previous.is(tok::comma) || Current.NestingLevel < 2) &&
421 !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at) &&
422 !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
423 nextIsMultilineString(State))
426 // Using CanBreakBefore here and below takes care of the decision whether the
427 // current style uses wrapping before or after operators for the given
429 if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
430 // If we need to break somewhere inside the LHS of a binary expression, we
431 // should also break after the operator. Otherwise, the formatting would
432 // hide the operator precedence, e.g. in:
433 // if (aaaaaaaaaaaaaa ==
434 // bbbbbbbbbbbbbb && c) {..
435 // For comparisons, we only apply this rule, if the LHS is a binary
436 // expression itself as otherwise, the line breaks seem superfluous.
437 // We need special cases for ">>" which we have split into two ">" while
438 // lexing in order to make template parsing easier.
439 bool IsComparison = (Previous.getPrecedence() == prec::Relational ||
440 Previous.getPrecedence() == prec::Equality ||
441 Previous.getPrecedence() == prec::Spaceship) &&
443 Previous.Previous->isNot(TT_BinaryOperator); // For >>.
444 bool LHSIsBinaryExpr =
445 Previous.Previous && Previous.Previous->EndsBinaryExpression;
446 if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() &&
447 Previous.getPrecedence() != prec::Assignment &&
448 State.Stack.back().BreakBeforeParameter)
450 } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
451 State.Stack.back().BreakBeforeParameter) {
455 // Same as above, but for the first "<<" operator.
456 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
457 State.Stack.back().BreakBeforeParameter &&
458 State.Stack.back().FirstLessLess == 0)
461 if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
462 // Always break after "template <...>" and leading annotations. This is only
463 // for cases where the entire line does not fit on a single line as a
464 // different LineFormatter would be used otherwise.
465 if (Previous.ClosesTemplateDeclaration)
466 return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No;
467 if (Previous.is(TT_FunctionAnnotationRParen))
469 if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
470 Current.isNot(TT_LeadingJavaAnnotation))
474 // If the return type spans multiple lines, wrap before the function name.
475 if ((Current.is(TT_FunctionDeclarationName) ||
476 (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) &&
477 !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter)
480 // The following could be precomputed as they do not depend on the state.
481 // However, as they should take effect only if the UnwrappedLine does not fit
482 // into the ColumnLimit, they are checked here in the ContinuationIndenter.
483 if (Style.ColumnLimit != 0 && Previous.BlockKind == BK_Block &&
484 Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment))
487 if (Current.is(tok::lessless) &&
488 ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
489 (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") ||
490 Previous.TokenText == "\'\\n\'"))))
493 if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
496 if (State.NoContinuation)
502 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
504 unsigned ExtraSpaces) {
505 const FormatToken &Current = *State.NextToken;
507 assert(!State.Stack.empty());
508 State.NoContinuation = false;
510 if ((Current.is(TT_ImplicitStringLiteral) &&
511 (Current.Previous->Tok.getIdentifierInfo() == nullptr ||
512 Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() ==
513 tok::pp_not_keyword))) {
515 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
516 if (Current.LastNewlineOffset != 0) {
517 // If there is a newline within this token, the final column will solely
518 // determined by the current end column.
519 State.Column = EndColumn;
521 unsigned StartColumn =
522 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
523 assert(EndColumn >= StartColumn);
524 State.Column += EndColumn - StartColumn;
526 moveStateToNextToken(State, DryRun, /*Newline=*/false);
530 unsigned Penalty = 0;
532 Penalty = addTokenOnNewLine(State, DryRun);
534 addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
536 return moveStateToNextToken(State, DryRun, Newline) + Penalty;
539 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
540 unsigned ExtraSpaces) {
541 FormatToken &Current = *State.NextToken;
542 const FormatToken &Previous = *State.NextToken->Previous;
543 if (Current.is(tok::equal) &&
544 (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
545 State.Stack.back().VariablePos == 0) {
546 State.Stack.back().VariablePos = State.Column;
547 // Move over * and & if they are bound to the variable name.
548 const FormatToken *Tok = &Previous;
549 while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) {
550 State.Stack.back().VariablePos -= Tok->ColumnWidth;
551 if (Tok->SpacesRequiredBefore != 0)
555 if (Previous.PartOfMultiVariableDeclStmt)
556 State.Stack.back().LastSpace = State.Stack.back().VariablePos;
559 unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
561 // Indent preprocessor directives after the hash if required.
562 int PPColumnCorrection = 0;
563 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
564 Previous.is(tok::hash) && State.FirstIndent > 0 &&
565 (State.Line->Type == LT_PreprocessorDirective ||
566 State.Line->Type == LT_ImportStatement)) {
567 Spaces += State.FirstIndent;
569 // For preprocessor indent with tabs, State.Column will be 1 because of the
570 // hash. This causes second-level indents onward to have an extra space
571 // after the tabs. We avoid this misalignment by subtracting 1 from the
572 // column value passed to replaceWhitespace().
573 if (Style.UseTab != FormatStyle::UT_Never)
574 PPColumnCorrection = -1;
578 Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
579 State.Column + Spaces + PPColumnCorrection);
581 // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
582 // declaration unless there is multiple inheritance.
583 if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
584 Current.is(TT_InheritanceColon))
585 State.Stack.back().NoLineBreak = true;
586 if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
587 Previous.is(TT_InheritanceColon))
588 State.Stack.back().NoLineBreak = true;
590 if (Current.is(TT_SelectorName) &&
591 !State.Stack.back().ObjCSelectorNameFound) {
593 std::max(State.FirstIndent + Style.ContinuationIndentWidth,
594 State.Stack.back().Indent);
595 unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
596 if (Current.LongestObjCSelectorName == 0)
597 State.Stack.back().AlignColons = false;
598 else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
599 State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName;
601 State.Stack.back().ColonPos = FirstColonPos;
604 // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by
605 // disallowing any further line breaks if there is no line break after the
606 // opening parenthesis. Don't break if it doesn't conserve columns.
607 if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak &&
608 Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
609 State.Column > getNewLineColumn(State) &&
610 (!Previous.Previous || !Previous.Previous->isOneOf(
611 tok::kw_for, tok::kw_while, tok::kw_switch)) &&
612 // Don't do this for simple (no expressions) one-argument function calls
613 // as that feels like needlessly wasting whitespace, e.g.:
618 // caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
619 Current.FakeLParens.size() > 0 &&
620 Current.FakeLParens.back() > prec::Unknown)
621 State.Stack.back().NoLineBreak = true;
622 if (Previous.is(TT_TemplateString) && Previous.opensScope())
623 State.Stack.back().NoLineBreak = true;
625 if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
626 Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) &&
627 (Current.isNot(TT_LineComment) || Previous.BlockKind == BK_BracedInit))
628 State.Stack.back().Indent = State.Column + Spaces;
629 if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style))
630 State.Stack.back().NoLineBreak = true;
631 if (startsSegmentOfBuilderTypeCall(Current) &&
632 State.Column > getNewLineColumn(State))
633 State.Stack.back().ContainsUnwrappedBuilder = true;
635 if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java)
636 State.Stack.back().NoLineBreak = true;
637 if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
638 (Previous.MatchingParen &&
639 (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10)))
640 // If there is a function call with long parameters, break before trailing
641 // calls. This prevents things like:
642 // EXPECT_CALL(SomeLongParameter).Times(
644 // We don't want to do this for short parameters as they can just be
646 State.Stack.back().NoLineBreak = true;
648 // Don't allow the RHS of an operator to be split over multiple lines unless
649 // there is a line-break right after the operator.
650 // Exclude relational operators, as there, it is always more desirable to
651 // have the LHS 'left' of the RHS.
652 const FormatToken *P = Current.getPreviousNonComment();
653 if (!Current.is(tok::comment) && P &&
654 (P->isOneOf(TT_BinaryOperator, tok::comma) ||
655 (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
656 !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
657 P->getPrecedence() != prec::Assignment &&
658 P->getPrecedence() != prec::Relational &&
659 P->getPrecedence() != prec::Spaceship) {
660 bool BreakBeforeOperator =
661 P->MustBreakBefore || P->is(tok::lessless) ||
662 (P->is(TT_BinaryOperator) &&
663 Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
664 (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
665 // Don't do this if there are only two operands. In these cases, there is
666 // always a nice vertical separation between them and the extra line break
668 bool HasTwoOperands =
669 P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr);
670 if ((!BreakBeforeOperator && !(HasTwoOperands && Style.AlignOperands)) ||
671 (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator))
672 State.Stack.back().NoLineBreakInOperand = true;
675 State.Column += Spaces;
676 if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
678 (Previous.Previous->isOneOf(tok::kw_if, tok::kw_for) ||
679 Previous.Previous->endsSequence(tok::kw_constexpr, tok::kw_if))) {
680 // Treat the condition inside an if as if it was a second function
681 // parameter, i.e. let nested calls have a continuation indent.
682 State.Stack.back().LastSpace = State.Column;
683 State.Stack.back().NestedBlockIndent = State.Column;
684 } else if (!Current.isOneOf(tok::comment, tok::caret) &&
685 ((Previous.is(tok::comma) &&
686 !Previous.is(TT_OverloadedOperator)) ||
687 (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
688 State.Stack.back().LastSpace = State.Column;
689 } else if (Previous.is(TT_CtorInitializerColon) &&
690 Style.BreakConstructorInitializers ==
691 FormatStyle::BCIS_AfterColon) {
692 State.Stack.back().Indent = State.Column;
693 State.Stack.back().LastSpace = State.Column;
694 } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr,
695 TT_CtorInitializerColon)) &&
696 ((Previous.getPrecedence() != prec::Assignment &&
697 (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
698 Previous.NextOperator)) ||
699 Current.StartsBinaryExpression)) {
700 // Indent relative to the RHS of the expression unless this is a simple
701 // assignment without binary expression on the RHS. Also indent relative to
702 // unary operators and the colons of constructor initializers.
703 State.Stack.back().LastSpace = State.Column;
704 } else if (Previous.is(TT_InheritanceColon)) {
705 State.Stack.back().Indent = State.Column;
706 State.Stack.back().LastSpace = State.Column;
707 } else if (Previous.opensScope()) {
708 // If a function has a trailing call, indent all parameters from the
709 // opening parenthesis. This avoids confusing indents like:
710 // OuterFunction(InnerFunctionCall( // break
711 // ParameterToInnerFunction)) // break
712 // .SecondInnerFunctionCall();
713 bool HasTrailingCall = false;
714 if (Previous.MatchingParen) {
715 const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
716 HasTrailingCall = Next && Next->isMemberAccess();
718 if (HasTrailingCall && State.Stack.size() > 1 &&
719 State.Stack[State.Stack.size() - 2].CallContinuation == 0)
720 State.Stack.back().LastSpace = State.Column;
724 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
726 FormatToken &Current = *State.NextToken;
727 const FormatToken &Previous = *State.NextToken->Previous;
729 // Extra penalty that needs to be added because of the way certain line
730 // breaks are chosen.
731 unsigned Penalty = 0;
733 const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
734 const FormatToken *NextNonComment = Previous.getNextNonComment();
736 NextNonComment = &Current;
737 // The first line break on any NestingLevel causes an extra penalty in order
738 // prefer similar line breaks.
739 if (!State.Stack.back().ContainsLineBreak)
741 State.Stack.back().ContainsLineBreak = true;
743 Penalty += State.NextToken->SplitPenalty;
745 // Breaking before the first "<<" is generally not desirable if the LHS is
746 // short. Also always add the penalty if the LHS is split over multiple lines
747 // to avoid unnecessary line breaks that just work around this penalty.
748 if (NextNonComment->is(tok::lessless) &&
749 State.Stack.back().FirstLessLess == 0 &&
750 (State.Column <= Style.ColumnLimit / 3 ||
751 State.Stack.back().BreakBeforeParameter))
752 Penalty += Style.PenaltyBreakFirstLessLess;
754 State.Column = getNewLineColumn(State);
756 // Indent nested blocks relative to this column, unless in a very specific
757 // JavaScript special case where:
759 // var loooooong_name =
764 // is common and should be formatted like a free-standing function. The same
765 // goes for wrapping before the lambda return type arrow.
766 if (!Current.is(TT_LambdaArrow) &&
767 (Style.Language != FormatStyle::LK_JavaScript ||
768 Current.NestingLevel != 0 || !PreviousNonComment ||
769 !PreviousNonComment->is(tok::equal) ||
770 !Current.isOneOf(Keywords.kw_async, Keywords.kw_function)))
771 State.Stack.back().NestedBlockIndent = State.Column;
773 if (NextNonComment->isMemberAccess()) {
774 if (State.Stack.back().CallContinuation == 0)
775 State.Stack.back().CallContinuation = State.Column;
776 } else if (NextNonComment->is(TT_SelectorName)) {
777 if (!State.Stack.back().ObjCSelectorNameFound) {
778 if (NextNonComment->LongestObjCSelectorName == 0) {
779 State.Stack.back().AlignColons = false;
781 State.Stack.back().ColonPos =
782 (shouldIndentWrappedSelectorName(Style, State.Line->Type)
783 ? std::max(State.Stack.back().Indent,
784 State.FirstIndent + Style.ContinuationIndentWidth)
785 : State.Stack.back().Indent) +
786 std::max(NextNonComment->LongestObjCSelectorName,
787 NextNonComment->ColumnWidth);
789 } else if (State.Stack.back().AlignColons &&
790 State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) {
791 State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth;
793 } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
794 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
795 // FIXME: This is hacky, find a better way. The problem is that in an ObjC
796 // method expression, the block should be aligned to the line starting it,
798 // [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
802 // Thus, we set LastSpace of the next higher NestingLevel, to which we move
803 // when we consume all of the "}"'s FakeRParens at the "{".
804 if (State.Stack.size() > 1)
805 State.Stack[State.Stack.size() - 2].LastSpace =
806 std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
807 Style.ContinuationIndentWidth;
810 if ((PreviousNonComment &&
811 PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
812 !State.Stack.back().AvoidBinPacking) ||
813 Previous.is(TT_BinaryOperator))
814 State.Stack.back().BreakBeforeParameter = false;
815 if (PreviousNonComment &&
816 PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) &&
817 Current.NestingLevel == 0)
818 State.Stack.back().BreakBeforeParameter = false;
819 if (NextNonComment->is(tok::question) ||
820 (PreviousNonComment && PreviousNonComment->is(tok::question)))
821 State.Stack.back().BreakBeforeParameter = true;
822 if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
823 State.Stack.back().BreakBeforeParameter = false;
826 unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
827 if (Current.is(tok::r_brace) && Current.MatchingParen &&
828 // Only strip trailing empty lines for l_braces that have children, i.e.
829 // for function expressions (lambdas, arrows, etc).
830 !Current.MatchingParen->Children.empty()) {
831 // lambdas and arrow functions are expressions, thus their r_brace is not
832 // on its own line, and thus not covered by UnwrappedLineFormatter's logic
833 // about removing empty lines on closing blocks. Special case them here.
834 MaxEmptyLinesToKeep = 1;
836 unsigned Newlines = std::max(
837 1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
838 bool ContinuePPDirective =
839 State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
840 Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
841 ContinuePPDirective);
844 if (!Current.isTrailingComment())
845 State.Stack.back().LastSpace = State.Column;
846 if (Current.is(tok::lessless))
847 // If we are breaking before a "<<", we always want to indent relative to
848 // RHS. This is necessary only for "<<", as we special-case it and don't
849 // always indent relative to the RHS.
850 State.Stack.back().LastSpace += 3; // 3 -> width of "<< ".
852 State.StartOfLineLevel = Current.NestingLevel;
853 State.LowestLevelOnLine = Current.NestingLevel;
855 // Any break on this level means that the parent level has been broken
856 // and we need to avoid bin packing there.
857 bool NestedBlockSpecialCase =
858 !Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
859 State.Stack[State.Stack.size() - 2].NestedBlockInlined;
860 if (!NestedBlockSpecialCase)
861 for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
862 State.Stack[i].BreakBeforeParameter = true;
864 if (PreviousNonComment &&
865 !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
866 (PreviousNonComment->isNot(TT_TemplateCloser) ||
867 Current.NestingLevel != 0) &&
868 !PreviousNonComment->isOneOf(
869 TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
870 TT_LeadingJavaAnnotation) &&
871 Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope())
872 State.Stack.back().BreakBeforeParameter = true;
874 // If we break after { or the [ of an array initializer, we should also break
875 // before the corresponding } or ].
876 if (PreviousNonComment &&
877 (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
878 opensProtoMessageField(*PreviousNonComment, Style)))
879 State.Stack.back().BreakBeforeClosingBrace = true;
881 if (State.Stack.back().AvoidBinPacking) {
882 // If we are breaking after '(', '{', '<', this is not bin packing
883 // unless AllowAllParametersOfDeclarationOnNextLine is false or this is a
884 // dict/object literal.
885 if (!Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
886 (!Style.AllowAllParametersOfDeclarationOnNextLine &&
887 State.Line->MustBeDeclaration) ||
888 Previous.is(TT_DictLiteral))
889 State.Stack.back().BreakBeforeParameter = true;
895 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
896 if (!State.NextToken || !State.NextToken->Previous)
898 FormatToken &Current = *State.NextToken;
899 const FormatToken &Previous = *Current.Previous;
900 // If we are continuing an expression, we want to use the continuation indent.
901 unsigned ContinuationIndent =
902 std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
903 Style.ContinuationIndentWidth;
904 const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
905 const FormatToken *NextNonComment = Previous.getNextNonComment();
907 NextNonComment = &Current;
909 // Java specific bits.
910 if (Style.Language == FormatStyle::LK_Java &&
911 Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends))
912 return std::max(State.Stack.back().LastSpace,
913 State.Stack.back().Indent + Style.ContinuationIndentWidth);
915 if (NextNonComment->is(tok::l_brace) && NextNonComment->BlockKind == BK_Block)
916 return Current.NestingLevel == 0 ? State.FirstIndent
917 : State.Stack.back().Indent;
918 if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
919 (Current.is(tok::greater) &&
920 (Style.Language == FormatStyle::LK_Proto ||
921 Style.Language == FormatStyle::LK_TextProto))) &&
922 State.Stack.size() > 1) {
923 if (Current.closesBlockOrBlockTypeList(Style))
924 return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
925 if (Current.MatchingParen &&
926 Current.MatchingParen->BlockKind == BK_BracedInit)
927 return State.Stack[State.Stack.size() - 2].LastSpace;
928 return State.FirstIndent;
930 // Indent a closing parenthesis at the previous level if followed by a semi or
931 // opening brace. This allows indentations such as:
940 if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
941 (!Current.Next || Current.Next->isOneOf(tok::semi, tok::l_brace)))
942 return State.Stack[State.Stack.size() - 2].LastSpace;
943 if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
944 return State.Stack[State.Stack.size() - 2].LastSpace;
945 if (Current.is(tok::identifier) && Current.Next &&
946 (Current.Next->is(TT_DictLiteral) ||
947 ((Style.Language == FormatStyle::LK_Proto ||
948 Style.Language == FormatStyle::LK_TextProto) &&
949 Current.Next->isOneOf(tok::less, tok::l_brace))))
950 return State.Stack.back().Indent;
951 if (NextNonComment->is(TT_ObjCStringLiteral) &&
952 State.StartOfStringLiteral != 0)
953 return State.StartOfStringLiteral - 1;
954 if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
955 return State.StartOfStringLiteral;
956 if (NextNonComment->is(tok::lessless) &&
957 State.Stack.back().FirstLessLess != 0)
958 return State.Stack.back().FirstLessLess;
959 if (NextNonComment->isMemberAccess()) {
960 if (State.Stack.back().CallContinuation == 0)
961 return ContinuationIndent;
962 return State.Stack.back().CallContinuation;
964 if (State.Stack.back().QuestionColumn != 0 &&
965 ((NextNonComment->is(tok::colon) &&
966 NextNonComment->is(TT_ConditionalExpr)) ||
967 Previous.is(TT_ConditionalExpr)))
968 return State.Stack.back().QuestionColumn;
969 if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0)
970 return State.Stack.back().VariablePos;
971 if ((PreviousNonComment &&
972 (PreviousNonComment->ClosesTemplateDeclaration ||
973 PreviousNonComment->isOneOf(
974 TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
975 TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
976 (!Style.IndentWrappedFunctionNames &&
977 NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName)))
978 return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent);
979 if (NextNonComment->is(TT_SelectorName)) {
980 if (!State.Stack.back().ObjCSelectorNameFound) {
981 unsigned MinIndent = State.Stack.back().Indent;
982 if (shouldIndentWrappedSelectorName(Style, State.Line->Type))
983 MinIndent = std::max(MinIndent,
984 State.FirstIndent + Style.ContinuationIndentWidth);
985 // If LongestObjCSelectorName is 0, we are indenting the first
986 // part of an ObjC selector (or a selector component which is
987 // not colon-aligned due to block formatting).
989 // Otherwise, we are indenting a subsequent part of an ObjC
990 // selector which should be colon-aligned to the longest
991 // component of the ObjC selector.
993 // In either case, we want to respect Style.IndentWrappedFunctionNames.
995 std::max(NextNonComment->LongestObjCSelectorName,
996 NextNonComment->ColumnWidth) -
997 NextNonComment->ColumnWidth;
999 if (!State.Stack.back().AlignColons)
1000 return State.Stack.back().Indent;
1001 if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth)
1002 return State.Stack.back().ColonPos - NextNonComment->ColumnWidth;
1003 return State.Stack.back().Indent;
1005 if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1006 return State.Stack.back().ColonPos;
1007 if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1008 if (State.Stack.back().StartOfArraySubscripts != 0)
1009 return State.Stack.back().StartOfArraySubscripts;
1010 return ContinuationIndent;
1013 // This ensure that we correctly format ObjC methods calls without inputs,
1014 // i.e. where the last element isn't selector like: [callee method];
1015 if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1016 NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr))
1017 return State.Stack.back().Indent;
1019 if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1020 Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon))
1021 return ContinuationIndent;
1022 if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1023 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral))
1024 return ContinuationIndent;
1025 if (NextNonComment->is(TT_CtorInitializerComma))
1026 return State.Stack.back().Indent;
1027 if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1028 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon)
1029 return State.Stack.back().Indent;
1030 if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1031 Style.BreakInheritanceList == FormatStyle::BILS_AfterColon)
1032 return State.Stack.back().Indent;
1033 if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1034 TT_InheritanceComma))
1035 return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1036 if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1037 !Current.isOneOf(tok::colon, tok::comment))
1038 return ContinuationIndent;
1039 if (Current.is(TT_ProtoExtensionLSquare))
1040 return State.Stack.back().Indent;
1041 if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment &&
1042 PreviousNonComment->isNot(tok::r_brace))
1043 // Ensure that we fall back to the continuation indent width instead of
1044 // just flushing continuations left.
1045 return State.Stack.back().Indent + Style.ContinuationIndentWidth;
1046 return State.Stack.back().Indent;
1049 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1050 bool DryRun, bool Newline) {
1051 assert(State.Stack.size());
1052 const FormatToken &Current = *State.NextToken;
1054 if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1055 State.Stack.back().NoLineBreakInOperand = false;
1056 if (Current.is(TT_InheritanceColon))
1057 State.Stack.back().AvoidBinPacking = true;
1058 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1059 if (State.Stack.back().FirstLessLess == 0)
1060 State.Stack.back().FirstLessLess = State.Column;
1062 State.Stack.back().LastOperatorWrapped = Newline;
1064 if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1065 State.Stack.back().LastOperatorWrapped = Newline;
1066 if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1067 !Current.Previous->is(TT_ConditionalExpr))
1068 State.Stack.back().LastOperatorWrapped = Newline;
1069 if (Current.is(TT_ArraySubscriptLSquare) &&
1070 State.Stack.back().StartOfArraySubscripts == 0)
1071 State.Stack.back().StartOfArraySubscripts = State.Column;
1072 if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1073 State.Stack.back().QuestionColumn = State.Column;
1074 if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1075 const FormatToken *Previous = Current.Previous;
1076 while (Previous && Previous->isTrailingComment())
1077 Previous = Previous->Previous;
1078 if (Previous && Previous->is(tok::question))
1079 State.Stack.back().QuestionColumn = State.Column;
1081 if (!Current.opensScope() && !Current.closesScope() &&
1082 !Current.is(TT_PointerOrReference))
1083 State.LowestLevelOnLine =
1084 std::min(State.LowestLevelOnLine, Current.NestingLevel);
1085 if (Current.isMemberAccess())
1086 State.Stack.back().StartOfFunctionCall =
1087 !Current.NextOperator ? 0 : State.Column;
1088 if (Current.is(TT_SelectorName))
1089 State.Stack.back().ObjCSelectorNameFound = true;
1090 if (Current.is(TT_CtorInitializerColon) &&
1091 Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1092 // Indent 2 from the column, so:
1093 // SomeClass::SomeClass()
1094 // : First(...), ...
1097 State.Stack.back().Indent =
1099 (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma
1102 State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1103 if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1104 State.Stack.back().AvoidBinPacking = true;
1105 State.Stack.back().BreakBeforeParameter = false;
1107 if (Current.is(TT_CtorInitializerColon) &&
1108 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1109 State.Stack.back().Indent =
1110 State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1111 State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1112 if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1113 State.Stack.back().AvoidBinPacking = true;
1115 if (Current.is(TT_InheritanceColon))
1116 State.Stack.back().Indent =
1117 State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1118 if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1119 State.Stack.back().NestedBlockIndent =
1120 State.Column + Current.ColumnWidth + 1;
1121 if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
1122 State.Stack.back().LastSpace = State.Column;
1124 // Insert scopes created by fake parenthesis.
1125 const FormatToken *Previous = Current.getPreviousNonComment();
1127 // Add special behavior to support a format commonly used for JavaScript
1129 // SomeFunction(function() {
1133 if (Current.isNot(tok::comment) && Previous &&
1134 Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1135 !Previous->is(TT_DictLiteral) && State.Stack.size() > 1) {
1136 if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1137 for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
1138 State.Stack[i].NoLineBreak = true;
1139 State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1142 (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) ||
1143 Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) &&
1144 !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) {
1145 State.Stack.back().NestedBlockInlined =
1147 (Previous->isNot(tok::l_paren) || Previous->ParameterCount > 1);
1150 moveStatePastFakeLParens(State, Newline);
1151 moveStatePastScopeCloser(State);
1152 bool AllowBreak = !State.Stack.back().NoLineBreak &&
1153 !State.Stack.back().NoLineBreakInOperand;
1154 moveStatePastScopeOpener(State, Newline);
1155 moveStatePastFakeRParens(State);
1157 if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1158 State.StartOfStringLiteral = State.Column + 1;
1159 else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0)
1160 State.StartOfStringLiteral = State.Column;
1161 else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1162 !Current.isStringLiteral())
1163 State.StartOfStringLiteral = 0;
1165 State.Column += Current.ColumnWidth;
1166 State.NextToken = State.NextToken->Next;
1169 handleEndOfLine(Current, State, DryRun, AllowBreak);
1172 Current.Role->formatFromToken(State, this, DryRun);
1173 // If the previous has a special role, let it consume tokens as appropriate.
1174 // It is necessary to start at the previous token for the only implemented
1175 // role (comma separated list). That way, the decision whether or not to break
1176 // after the "{" is already done and both options are tried and evaluated.
1177 // FIXME: This is ugly, find a better way.
1178 if (Previous && Previous->Role)
1179 Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1184 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1186 const FormatToken &Current = *State.NextToken;
1187 const FormatToken *Previous = Current.getPreviousNonComment();
1189 // Don't add extra indentation for the first fake parenthesis after
1190 // 'return', assignments or opening <({[. The indentation for these cases
1191 // is special cased.
1192 bool SkipFirstExtraIndent =
1193 (Previous && (Previous->opensScope() ||
1194 Previous->isOneOf(tok::semi, tok::kw_return) ||
1195 (Previous->getPrecedence() == prec::Assignment &&
1196 Style.AlignOperands) ||
1197 Previous->is(TT_ObjCMethodExpr)));
1198 for (SmallVectorImpl<prec::Level>::const_reverse_iterator
1199 I = Current.FakeLParens.rbegin(),
1200 E = Current.FakeLParens.rend();
1202 ParenState NewParenState = State.Stack.back();
1203 NewParenState.Tok = nullptr;
1204 NewParenState.ContainsLineBreak = false;
1205 NewParenState.LastOperatorWrapped = true;
1206 NewParenState.NoLineBreak =
1207 NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand;
1209 // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1210 if (*I > prec::Comma)
1211 NewParenState.AvoidBinPacking = false;
1213 // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1214 // a builder type call after 'return' or, if the alignment after opening
1215 // brackets is disabled.
1216 if (!Current.isTrailingComment() &&
1217 (Style.AlignOperands || *I < prec::Assignment) &&
1218 (!Previous || Previous->isNot(tok::kw_return) ||
1219 (Style.Language != FormatStyle::LK_Java && *I > 0)) &&
1220 (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1221 *I != prec::Comma || Current.NestingLevel == 0))
1222 NewParenState.Indent =
1223 std::max(std::max(State.Column, NewParenState.Indent),
1224 State.Stack.back().LastSpace);
1226 // Do not indent relative to the fake parentheses inserted for "." or "->".
1227 // This is a special case to make the following to statements consistent:
1228 // OuterFunction(InnerFunctionCall( // break
1229 // ParameterToInnerFunction));
1230 // OuterFunction(SomeObject.InnerFunctionCall( // break
1231 // ParameterToInnerFunction));
1232 if (*I > prec::Unknown)
1233 NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1234 if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) &&
1235 Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign)
1236 NewParenState.StartOfFunctionCall = State.Column;
1238 // Always indent conditional expressions. Never indent expression where
1239 // the 'operator' is ',', ';' or an assignment (i.e. *I <=
1240 // prec::Assignment) as those have different indentation rules. Indent
1241 // other expression, unless the indentation needs to be skipped.
1242 if (*I == prec::Conditional ||
1243 (!SkipFirstExtraIndent && *I > prec::Assignment &&
1244 !Current.isTrailingComment()))
1245 NewParenState.Indent += Style.ContinuationIndentWidth;
1246 if ((Previous && !Previous->opensScope()) || *I != prec::Comma)
1247 NewParenState.BreakBeforeParameter = false;
1248 State.Stack.push_back(NewParenState);
1249 SkipFirstExtraIndent = false;
1253 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1254 for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1255 unsigned VariablePos = State.Stack.back().VariablePos;
1256 if (State.Stack.size() == 1) {
1257 // Do not pop the last element.
1260 State.Stack.pop_back();
1261 State.Stack.back().VariablePos = VariablePos;
1265 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1267 const FormatToken &Current = *State.NextToken;
1268 if (!Current.opensScope())
1271 if (Current.MatchingParen && Current.BlockKind == BK_Block) {
1272 moveStateToNewBlock(State);
1277 unsigned LastSpace = State.Stack.back().LastSpace;
1278 bool AvoidBinPacking;
1279 bool BreakBeforeParameter = false;
1280 unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall,
1281 State.Stack.back().NestedBlockIndent);
1282 if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1283 opensProtoMessageField(Current, Style)) {
1284 if (Current.opensBlockOrBlockTypeList(Style)) {
1285 NewIndent = Style.IndentWidth +
1286 std::min(State.Column, State.Stack.back().NestedBlockIndent);
1288 NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth;
1290 const FormatToken *NextNoComment = Current.getNextNonComment();
1291 bool EndsInComma = Current.MatchingParen &&
1292 Current.MatchingParen->Previous &&
1293 Current.MatchingParen->Previous->is(tok::comma);
1294 AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1295 Style.Language == FormatStyle::LK_Proto ||
1296 Style.Language == FormatStyle::LK_TextProto ||
1297 !Style.BinPackArguments ||
1299 NextNoComment->isOneOf(TT_DesignatedInitializerPeriod,
1300 TT_DesignatedInitializerLSquare));
1301 BreakBeforeParameter = EndsInComma;
1302 if (Current.ParameterCount > 1)
1303 NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1305 NewIndent = Style.ContinuationIndentWidth +
1306 std::max(State.Stack.back().LastSpace,
1307 State.Stack.back().StartOfFunctionCall);
1309 // Ensure that different different brackets force relative alignment, e.g.:
1310 // void SomeFunction(vector< // break
1312 // FIXME: We likely want to do this for more combinations of brackets.
1313 if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1314 NewIndent = std::max(NewIndent, State.Stack.back().Indent);
1315 LastSpace = std::max(LastSpace, State.Stack.back().Indent);
1319 Current.MatchingParen &&
1320 Current.MatchingParen->getPreviousNonComment() &&
1321 Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1323 // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1324 // for backwards compatibility.
1325 bool ObjCBinPackProtocolList =
1326 (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1327 Style.BinPackParameters) ||
1328 Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1330 bool BinPackDeclaration =
1331 (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1332 (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1335 (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) ||
1336 (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1337 (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1338 (Style.ExperimentalAutoDetectBinPacking &&
1339 (Current.PackingKind == PPK_OnePerLine ||
1340 (!BinPackInconclusiveFunctions &&
1341 Current.PackingKind == PPK_Inconclusive)));
1343 if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen) {
1344 if (Style.ColumnLimit) {
1345 // If this '[' opens an ObjC call, determine whether all parameters fit
1346 // into one line and put one per line if they don't.
1347 if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1348 getColumnLimit(State))
1349 BreakBeforeParameter = true;
1351 // For ColumnLimit = 0, we have to figure out whether there is or has to
1352 // be a line break within this call.
1353 for (const FormatToken *Tok = &Current;
1354 Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1355 if (Tok->MustBreakBefore ||
1356 (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1357 BreakBeforeParameter = true;
1364 if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma)
1365 BreakBeforeParameter = true;
1367 // Generally inherit NoLineBreak from the current scope to nested scope.
1368 // However, don't do this for non-empty nested blocks, dict literals and
1369 // array literals as these follow different indentation rules.
1371 Current.Children.empty() &&
1372 !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1373 (State.Stack.back().NoLineBreak ||
1374 State.Stack.back().NoLineBreakInOperand ||
1375 (Current.is(TT_TemplateOpener) &&
1376 State.Stack.back().ContainsUnwrappedBuilder));
1377 State.Stack.push_back(
1378 ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1379 State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1380 State.Stack.back().BreakBeforeParameter = BreakBeforeParameter;
1381 State.Stack.back().HasMultipleNestedBlocks = Current.BlockParameterCount > 1;
1382 State.Stack.back().IsInsideObjCArrayLiteral =
1383 Current.is(TT_ArrayInitializerLSquare) && Current.Previous &&
1384 Current.Previous->is(tok::at);
1387 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1388 const FormatToken &Current = *State.NextToken;
1389 if (!Current.closesScope())
1392 // If we encounter a closing ), ], } or >, we can remove a level from our
1394 if (State.Stack.size() > 1 &&
1395 (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1396 (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1397 State.NextToken->is(TT_TemplateCloser) ||
1398 (Current.is(tok::greater) && Current.is(TT_DictLiteral))))
1399 State.Stack.pop_back();
1401 // Reevaluate whether ObjC message arguments fit into one line.
1402 // If a receiver spans multiple lines, e.g.:
1403 // [[object block:^{
1406 // BreakBeforeParameter is calculated based on an incorrect assumption
1407 // (it is checked whether the whole expression fits into one line without
1408 // considering a line break inside a message receiver).
1409 // We check whether arguements fit after receiver scope closer (into the same
1411 if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen &&
1412 Current.MatchingParen->Previous) {
1413 const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1414 if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1415 CurrentScopeOpener.MatchingParen) {
1416 int NecessarySpaceInLine =
1417 getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1418 CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1419 if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1421 State.Stack.back().BreakBeforeParameter = false;
1425 if (Current.is(tok::r_square)) {
1426 // If this ends the array subscript expr, reset the corresponding value.
1427 const FormatToken *NextNonComment = Current.getNextNonComment();
1428 if (NextNonComment && NextNonComment->isNot(tok::l_square))
1429 State.Stack.back().StartOfArraySubscripts = 0;
1433 void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1434 unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1435 // ObjC block sometimes follow special indentation rules.
1436 unsigned NewIndent =
1437 NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1438 ? Style.ObjCBlockIndentWidth
1439 : Style.IndentWidth);
1440 State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1441 State.Stack.back().LastSpace,
1442 /*AvoidBinPacking=*/true,
1443 /*NoLineBreak=*/false));
1444 State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1445 State.Stack.back().BreakBeforeParameter = true;
1448 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1450 encoding::Encoding Encoding) {
1451 size_t LastNewlinePos = Text.find_last_of("\n");
1452 if (LastNewlinePos == StringRef::npos) {
1453 return StartColumn +
1454 encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
1456 return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
1457 /*StartColumn=*/0, TabWidth, Encoding);
1461 unsigned ContinuationIndenter::reformatRawStringLiteral(
1462 const FormatToken &Current, LineState &State,
1463 const FormatStyle &RawStringStyle, bool DryRun) {
1464 unsigned StartColumn = State.Column - Current.ColumnWidth;
1465 StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
1466 StringRef NewDelimiter =
1467 getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
1468 if (NewDelimiter.empty() || OldDelimiter.empty())
1469 NewDelimiter = OldDelimiter;
1470 // The text of a raw string is between the leading 'R"delimiter(' and the
1471 // trailing 'delimiter)"'.
1472 unsigned OldPrefixSize = 3 + OldDelimiter.size();
1473 unsigned OldSuffixSize = 2 + OldDelimiter.size();
1474 // We create a virtual text environment which expects a null-terminated
1475 // string, so we cannot use StringRef.
1476 std::string RawText =
1477 Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize);
1478 if (NewDelimiter != OldDelimiter) {
1479 // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
1481 std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
1482 if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
1483 NewDelimiter = OldDelimiter;
1486 unsigned NewPrefixSize = 3 + NewDelimiter.size();
1487 unsigned NewSuffixSize = 2 + NewDelimiter.size();
1489 // The first start column is the column the raw text starts after formatting.
1490 unsigned FirstStartColumn = StartColumn + NewPrefixSize;
1492 // The next start column is the intended indentation a line break inside
1493 // the raw string at level 0. It is determined by the following rules:
1494 // - if the content starts on newline, it is one level more than the current
1496 // - if the content does not start on a newline, it is the first start
1498 // These rules have the advantage that the formatted content both does not
1499 // violate the rectangle rule and visually flows within the surrounding
1501 bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
1502 unsigned NextStartColumn =
1503 ContentStartsOnNewline
1504 ? State.Stack.back().NestedBlockIndent + Style.IndentWidth
1507 // The last start column is the column the raw string suffix starts if it is
1508 // put on a newline.
1509 // The last start column is the intended indentation of the raw string postfix
1510 // if it is put on a newline. It is determined by the following rules:
1511 // - if the raw string prefix starts on a newline, it is the column where
1512 // that raw string prefix starts, and
1513 // - if the raw string prefix does not start on a newline, it is the current
1515 unsigned LastStartColumn = Current.NewlinesBefore
1516 ? FirstStartColumn - NewPrefixSize
1517 : State.Stack.back().NestedBlockIndent;
1519 std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
1520 RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
1521 FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
1522 /*Status=*/nullptr);
1524 auto NewCode = applyAllReplacements(RawText, Fixes.first);
1525 tooling::Replacements NoFixes;
1527 State.Column += Current.ColumnWidth;
1531 if (NewDelimiter != OldDelimiter) {
1532 // In 'R"delimiter(...', the delimiter starts 2 characters after the start
1534 SourceLocation PrefixDelimiterStart =
1535 Current.Tok.getLocation().getLocWithOffset(2);
1536 auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
1537 SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1540 << "Failed to update the prefix delimiter of a raw string: "
1541 << llvm::toString(std::move(PrefixErr)) << "\n";
1543 // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
1544 // position length - 1 - |delimiter|.
1545 SourceLocation SuffixDelimiterStart =
1546 Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
1547 1 - OldDelimiter.size());
1548 auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
1549 SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1552 << "Failed to update the suffix delimiter of a raw string: "
1553 << llvm::toString(std::move(SuffixErr)) << "\n";
1556 SourceLocation OriginLoc =
1557 Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
1558 for (const tooling::Replacement &Fix : Fixes.first) {
1559 auto Err = Whitespaces.addReplacement(tooling::Replacement(
1560 SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
1561 Fix.getLength(), Fix.getReplacementText()));
1563 llvm::errs() << "Failed to reformat raw string: "
1564 << llvm::toString(std::move(Err)) << "\n";
1568 unsigned RawLastLineEndColumn = getLastLineEndColumn(
1569 *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
1570 State.Column = RawLastLineEndColumn + NewSuffixSize;
1571 // Since we're updating the column to after the raw string literal here, we
1572 // have to manually add the penalty for the prefix R"delim( over the column
1574 unsigned PrefixExcessCharacters =
1575 StartColumn + NewPrefixSize > Style.ColumnLimit ?
1576 StartColumn + NewPrefixSize - Style.ColumnLimit : 0;
1577 return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
1580 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
1582 // Break before further function parameters on all levels.
1583 for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1584 State.Stack[i].BreakBeforeParameter = true;
1586 unsigned ColumnsUsed = State.Column;
1587 // We can only affect layout of the first and the last line, so the penalty
1588 // for all other lines is constant, and we ignore it.
1589 State.Column = Current.LastLineColumnWidth;
1591 if (ColumnsUsed > getColumnLimit(State))
1592 return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
1596 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
1597 LineState &State, bool DryRun,
1599 unsigned Penalty = 0;
1600 // Compute the raw string style to use in case this is a raw string literal
1601 // that can be reformatted.
1602 auto RawStringStyle = getRawStringStyle(Current, State);
1603 if (RawStringStyle && !Current.Finalized) {
1604 Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun);
1605 } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
1606 // Don't break multi-line tokens other than block comments and raw string
1607 // literals. Instead, just update the state.
1608 Penalty = addMultilineToken(Current, State);
1609 } else if (State.Line->Type != LT_ImportStatement) {
1610 // We generally don't break import statements.
1611 LineState OriginalState = State;
1613 // Whether we force the reflowing algorithm to stay strictly within the
1615 bool Strict = false;
1616 // Whether the first non-strict attempt at reflowing did intentionally
1617 // exceed the column limit.
1618 bool Exceeded = false;
1619 std::tie(Penalty, Exceeded) = breakProtrudingToken(
1620 Current, State, AllowBreak, /*DryRun=*/true, Strict);
1622 // If non-strict reflowing exceeds the column limit, try whether strict
1623 // reflowing leads to an overall lower penalty.
1624 LineState StrictState = OriginalState;
1625 unsigned StrictPenalty =
1626 breakProtrudingToken(Current, StrictState, AllowBreak,
1627 /*DryRun=*/true, /*Strict=*/true)
1629 Strict = StrictPenalty <= Penalty;
1631 Penalty = StrictPenalty;
1632 State = StrictState;
1636 // If we're not in dry-run mode, apply the changes with the decision on
1637 // strictness made above.
1638 breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
1642 if (State.Column > getColumnLimit(State)) {
1643 unsigned ExcessCharacters = State.Column - getColumnLimit(State);
1644 Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
1649 // Returns the enclosing function name of a token, or the empty string if not
1651 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
1652 // Look for: 'function(' or 'function<templates>(' before Current.
1653 auto Tok = Current.getPreviousNonComment();
1654 if (!Tok || !Tok->is(tok::l_paren))
1656 Tok = Tok->getPreviousNonComment();
1659 if (Tok->is(TT_TemplateCloser)) {
1660 Tok = Tok->MatchingParen;
1662 Tok = Tok->getPreviousNonComment();
1664 if (!Tok || !Tok->is(tok::identifier))
1666 return Tok->TokenText;
1669 llvm::Optional<FormatStyle>
1670 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
1671 const LineState &State) {
1672 if (!Current.isStringLiteral())
1674 auto Delimiter = getRawStringDelimiter(Current.TokenText);
1677 auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
1678 if (!RawStringStyle && Delimiter->empty())
1679 RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
1680 getEnclosingFunctionName(Current));
1681 if (!RawStringStyle)
1683 RawStringStyle->ColumnLimit = getColumnLimit(State);
1684 return RawStringStyle;
1687 std::unique_ptr<BreakableToken> ContinuationIndenter::createBreakableToken(
1688 const FormatToken &Current, LineState &State, bool AllowBreak) {
1689 unsigned StartColumn = State.Column - Current.ColumnWidth;
1690 if (Current.isStringLiteral()) {
1691 // FIXME: String literal breaking is currently disabled for Java and JS, as
1692 // it requires strings to be merged using "+" which we don't support.
1693 if (Style.Language == FormatStyle::LK_Java ||
1694 Style.Language == FormatStyle::LK_JavaScript ||
1695 !Style.BreakStringLiterals ||
1699 // Don't break string literals inside preprocessor directives (except for
1700 // #define directives, as their contents are stored in separate lines and
1701 // are not affected by this check).
1702 // This way we avoid breaking code with line directives and unknown
1703 // preprocessor directives that contain long string literals.
1704 if (State.Line->Type == LT_PreprocessorDirective)
1706 // Exempts unterminated string literals from line breaking. The user will
1707 // likely want to terminate the string before any line breaking is done.
1708 if (Current.IsUnterminatedLiteral)
1710 // Don't break string literals inside Objective-C array literals (doing so
1711 // raises the warning -Wobjc-string-concatenation).
1712 if (State.Stack.back().IsInsideObjCArrayLiteral) {
1716 StringRef Text = Current.TokenText;
1719 // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
1720 // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
1721 // reduce the overhead) for each FormatToken, which is a string, so that we
1722 // don't run multiple checks here on the hot path.
1723 if ((Text.endswith(Postfix = "\"") &&
1724 (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") ||
1725 Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") ||
1726 Text.startswith(Prefix = "u8\"") ||
1727 Text.startswith(Prefix = "L\""))) ||
1728 (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) {
1729 // We need this to address the case where there is an unbreakable tail
1730 // only if certain other formatting decisions have been taken. The
1731 // UnbreakableTailLength of Current is an overapproximation is that case
1732 // and we need to be correct here.
1733 unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
1735 : Current.UnbreakableTailLength;
1736 return llvm::make_unique<BreakableStringLiteral>(
1737 Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
1738 State.Line->InPPDirective, Encoding, Style);
1740 } else if (Current.is(TT_BlockComment)) {
1741 if (!Style.ReflowComments ||
1742 // If a comment token switches formatting, like
1743 // /* clang-format on */, we don't want to break it further,
1744 // but we may still want to adjust its indentation.
1745 switchesFormatting(Current)) {
1748 return llvm::make_unique<BreakableBlockComment>(
1749 Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1750 State.Line->InPPDirective, Encoding, Style);
1751 } else if (Current.is(TT_LineComment) &&
1752 (Current.Previous == nullptr ||
1753 Current.Previous->isNot(TT_ImplicitStringLiteral))) {
1754 if (!Style.ReflowComments ||
1755 CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
1756 switchesFormatting(Current))
1758 return llvm::make_unique<BreakableLineCommentSection>(
1759 Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1760 /*InPPDirective=*/false, Encoding, Style);
1765 std::pair<unsigned, bool>
1766 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
1767 LineState &State, bool AllowBreak,
1768 bool DryRun, bool Strict) {
1769 std::unique_ptr<const BreakableToken> Token =
1770 createBreakableToken(Current, State, AllowBreak);
1773 assert(Token->getLineCount() > 0);
1774 unsigned ColumnLimit = getColumnLimit(State);
1775 if (Current.is(TT_LineComment)) {
1776 // We don't insert backslashes when breaking line comments.
1777 ColumnLimit = Style.ColumnLimit;
1779 if (Current.UnbreakableTailLength >= ColumnLimit)
1781 // ColumnWidth was already accounted into State.Column before calling
1782 // breakProtrudingToken.
1783 unsigned StartColumn = State.Column - Current.ColumnWidth;
1784 unsigned NewBreakPenalty = Current.isStringLiteral()
1785 ? Style.PenaltyBreakString
1786 : Style.PenaltyBreakComment;
1787 // Stores whether we intentionally decide to let a line exceed the column
1789 bool Exceeded = false;
1790 // Stores whether we introduce a break anywhere in the token.
1791 bool BreakInserted = Token->introducesBreakBeforeToken();
1792 // Store whether we inserted a new line break at the end of the previous
1794 bool NewBreakBefore = false;
1795 // We use a conservative reflowing strategy. Reflow starts after a line is
1796 // broken or the corresponding whitespace compressed. Reflow ends as soon as a
1797 // line that doesn't get reflown with the previous line is reached.
1798 bool Reflow = false;
1799 // Keep track of where we are in the token:
1800 // Where we are in the content of the current logical line.
1801 unsigned TailOffset = 0;
1802 // The column number we're currently at.
1803 unsigned ContentStartColumn =
1804 Token->getContentStartColumn(0, /*Break=*/false);
1805 // The number of columns left in the current logical line after TailOffset.
1806 unsigned RemainingTokenColumns =
1807 Token->getRemainingLength(0, TailOffset, ContentStartColumn);
1808 // Adapt the start of the token, for example indent.
1810 Token->adaptStartOfLine(0, Whitespaces);
1812 unsigned ContentIndent = 0;
1813 unsigned Penalty = 0;
1814 LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
1815 << StartColumn << ".\n");
1816 for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
1817 LineIndex != EndIndex; ++LineIndex) {
1818 LLVM_DEBUG(llvm::dbgs()
1819 << " Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
1820 NewBreakBefore = false;
1821 // If we did reflow the previous line, we'll try reflowing again. Otherwise
1822 // we'll start reflowing if the current line is broken or whitespace is
1824 bool TryReflow = Reflow;
1825 // Break the current token until we can fit the rest of the line.
1826 while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
1827 LLVM_DEBUG(llvm::dbgs() << " Over limit, need: "
1828 << (ContentStartColumn + RemainingTokenColumns)
1829 << ", space: " << ColumnLimit
1830 << ", reflown prefix: " << ContentStartColumn
1831 << ", offset in line: " << TailOffset << "\n");
1832 // If the current token doesn't fit, find the latest possible split in the
1833 // current line so that breaking at it will be under the column limit.
1834 // FIXME: Use the earliest possible split while reflowing to correctly
1835 // compress whitespace within a line.
1836 BreakableToken::Split Split =
1837 Token->getSplit(LineIndex, TailOffset, ColumnLimit,
1838 ContentStartColumn, CommentPragmasRegex);
1839 if (Split.first == StringRef::npos) {
1840 // No break opportunity - update the penalty and continue with the next
1842 if (LineIndex < EndIndex - 1)
1843 // The last line's penalty is handled in addNextStateToQueue().
1844 Penalty += Style.PenaltyExcessCharacter *
1845 (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
1846 LLVM_DEBUG(llvm::dbgs() << " No break opportunity.\n");
1849 assert(Split.first != 0);
1851 if (Token->supportsReflow()) {
1852 // Check whether the next natural split point after the current one can
1853 // still fit the line, either because we can compress away whitespace,
1854 // or because the penalty the excess characters introduce is lower than
1855 // the break penalty.
1856 // We only do this for tokens that support reflowing, and thus allow us
1857 // to change the whitespace arbitrarily (e.g. comments).
1858 // Other tokens, like string literals, can be broken on arbitrary
1861 // First, compute the columns from TailOffset to the next possible split
1865 // // Some text that breaks
1868 // ^-------- to split columns
1870 // ^--------------- to next split columns
1871 unsigned ToSplitColumns = Token->getRangeLength(
1872 LineIndex, TailOffset, Split.first, ContentStartColumn);
1873 LLVM_DEBUG(llvm::dbgs() << " ToSplit: " << ToSplitColumns << "\n");
1875 BreakableToken::Split NextSplit = Token->getSplit(
1876 LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
1877 ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
1878 // Compute the columns necessary to fit the next non-breakable sequence
1879 // into the current line.
1880 unsigned ToNextSplitColumns = 0;
1881 if (NextSplit.first == StringRef::npos) {
1882 ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
1883 ContentStartColumn);
1885 ToNextSplitColumns = Token->getRangeLength(
1886 LineIndex, TailOffset,
1887 Split.first + Split.second + NextSplit.first, ContentStartColumn);
1889 // Compress the whitespace between the break and the start of the next
1890 // unbreakable sequence.
1891 ToNextSplitColumns =
1892 Token->getLengthAfterCompression(ToNextSplitColumns, Split);
1893 LLVM_DEBUG(llvm::dbgs()
1894 << " ContentStartColumn: " << ContentStartColumn << "\n");
1895 LLVM_DEBUG(llvm::dbgs()
1896 << " ToNextSplit: " << ToNextSplitColumns << "\n");
1897 // If the whitespace compression makes us fit, continue on the current
1899 bool ContinueOnLine =
1900 ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
1901 unsigned ExcessCharactersPenalty = 0;
1902 if (!ContinueOnLine && !Strict) {
1903 // Similarly, if the excess characters' penalty is lower than the
1904 // penalty of introducing a new break, continue on the current line.
1905 ExcessCharactersPenalty =
1906 (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
1907 Style.PenaltyExcessCharacter;
1908 LLVM_DEBUG(llvm::dbgs()
1909 << " Penalty excess: " << ExcessCharactersPenalty
1910 << "\n break : " << NewBreakPenalty << "\n");
1911 if (ExcessCharactersPenalty < NewBreakPenalty) {
1913 ContinueOnLine = true;
1916 if (ContinueOnLine) {
1917 LLVM_DEBUG(llvm::dbgs() << " Continuing on line...\n");
1918 // The current line fits after compressing the whitespace - reflow
1919 // the next line into it if possible.
1922 Token->compressWhitespace(LineIndex, TailOffset, Split,
1924 // When we continue on the same line, leave one space between content.
1925 ContentStartColumn += ToSplitColumns + 1;
1926 Penalty += ExcessCharactersPenalty;
1927 TailOffset += Split.first + Split.second;
1928 RemainingTokenColumns = Token->getRemainingLength(
1929 LineIndex, TailOffset, ContentStartColumn);
1933 LLVM_DEBUG(llvm::dbgs() << " Breaking...\n");
1934 // Update the ContentIndent only if the current line was not reflown with
1935 // the previous line, since in that case the previous line should still
1936 // determine the ContentIndent. Also never intent the last line.
1938 ContentIndent = Token->getContentIndent(LineIndex);
1939 LLVM_DEBUG(llvm::dbgs()
1940 << " ContentIndent: " << ContentIndent << "\n");
1941 ContentStartColumn = ContentIndent + Token->getContentStartColumn(
1942 LineIndex, /*Break=*/true);
1944 unsigned NewRemainingTokenColumns = Token->getRemainingLength(
1945 LineIndex, TailOffset + Split.first + Split.second,
1946 ContentStartColumn);
1947 if (NewRemainingTokenColumns == 0) {
1948 // No content to indent.
1950 ContentStartColumn =
1951 Token->getContentStartColumn(LineIndex, /*Break=*/true);
1952 NewRemainingTokenColumns = Token->getRemainingLength(
1953 LineIndex, TailOffset + Split.first + Split.second,
1954 ContentStartColumn);
1957 // When breaking before a tab character, it may be moved by a few columns,
1958 // but will still be expanded to the next tab stop, so we don't save any
1960 if (NewRemainingTokenColumns == RemainingTokenColumns) {
1961 // FIXME: Do we need to adjust the penalty?
1964 assert(NewRemainingTokenColumns < RemainingTokenColumns);
1966 LLVM_DEBUG(llvm::dbgs() << " Breaking at: " << TailOffset + Split.first
1967 << ", " << Split.second << "\n");
1969 Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
1972 Penalty += NewBreakPenalty;
1973 TailOffset += Split.first + Split.second;
1974 RemainingTokenColumns = NewRemainingTokenColumns;
1975 BreakInserted = true;
1976 NewBreakBefore = true;
1978 // In case there's another line, prepare the state for the start of the next
1980 if (LineIndex + 1 != EndIndex) {
1981 unsigned NextLineIndex = LineIndex + 1;
1983 // After breaking a line, try to reflow the next line into the current
1984 // one once RemainingTokenColumns fits.
1987 // We decided that we want to try reflowing the next line into the
1989 // We will now adjust the state as if the reflow is successful (in
1990 // preparation for the next line), and see whether that works. If we
1991 // decide that we cannot reflow, we will later reset the state to the
1992 // start of the next line.
1994 // As we did not continue breaking the line, RemainingTokenColumns is
1995 // known to fit after ContentStartColumn. Adapt ContentStartColumn to
1996 // the position at which we want to format the next line if we do
1998 // When we reflow, we need to add a space between the end of the current
1999 // line and the next line's start column.
2000 ContentStartColumn += RemainingTokenColumns + 1;
2001 // Get the split that we need to reflow next logical line into the end
2002 // of the current one; the split will include any leading whitespace of
2003 // the next logical line.
2004 BreakableToken::Split SplitBeforeNext =
2005 Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2006 LLVM_DEBUG(llvm::dbgs()
2007 << " Size of reflown text: " << ContentStartColumn
2008 << "\n Potential reflow split: ");
2009 if (SplitBeforeNext.first != StringRef::npos) {
2010 LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2011 << SplitBeforeNext.second << "\n");
2012 TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2013 // If the rest of the next line fits into the current line below the
2014 // column limit, we can safely reflow.
2015 RemainingTokenColumns = Token->getRemainingLength(
2016 NextLineIndex, TailOffset, ContentStartColumn);
2018 if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2019 LLVM_DEBUG(llvm::dbgs()
2020 << " Over limit after reflow, need: "
2021 << (ContentStartColumn + RemainingTokenColumns)
2022 << ", space: " << ColumnLimit
2023 << ", reflown prefix: " << ContentStartColumn
2024 << ", offset in line: " << TailOffset << "\n");
2025 // If the whole next line does not fit, try to find a point in
2026 // the next line at which we can break so that attaching the part
2027 // of the next line to that break point onto the current line is
2028 // below the column limit.
2029 BreakableToken::Split Split =
2030 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2031 ContentStartColumn, CommentPragmasRegex);
2032 if (Split.first == StringRef::npos) {
2033 LLVM_DEBUG(llvm::dbgs() << " Did not find later break\n");
2036 // Check whether the first split point gets us below the column
2037 // limit. Note that we will execute this split below as part of
2038 // the normal token breaking and reflow logic within the line.
2039 unsigned ToSplitColumns = Token->getRangeLength(
2040 NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2041 if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2042 LLVM_DEBUG(llvm::dbgs() << " Next split protrudes, need: "
2043 << (ContentStartColumn + ToSplitColumns)
2044 << ", space: " << ColumnLimit);
2045 unsigned ExcessCharactersPenalty =
2046 (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2047 Style.PenaltyExcessCharacter;
2048 if (NewBreakPenalty < ExcessCharactersPenalty) {
2055 LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2059 // If we didn't reflow into the next line, the only space to consider is
2060 // the next logical line. Reset our state to match the start of the next
2063 ContentStartColumn =
2064 Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2065 RemainingTokenColumns = Token->getRemainingLength(
2066 NextLineIndex, TailOffset, ContentStartColumn);
2067 // Adapt the start of the token, for example indent.
2069 Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2071 // If we found a reflow split and have added a new break before the next
2072 // line, we are going to remove the line break at the start of the next
2073 // logical line. For example, here we'll add a new line break after
2074 // 'text', and subsequently delete the line break between 'that' and
2076 // // some text that
2081 // When adding the line break, we also added the penalty for it, so we
2082 // need to subtract that penalty again when we remove the line break due
2084 if (NewBreakBefore) {
2085 assert(Penalty >= NewBreakPenalty);
2086 Penalty -= NewBreakPenalty;
2089 Token->reflow(NextLineIndex, Whitespaces);
2094 BreakableToken::Split SplitAfterLastLine =
2095 Token->getSplitAfterLastLine(TailOffset);
2096 if (SplitAfterLastLine.first != StringRef::npos) {
2097 LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2099 Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2101 ContentStartColumn =
2102 Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2103 RemainingTokenColumns = Token->getRemainingLength(
2104 Token->getLineCount() - 1,
2105 TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2106 ContentStartColumn);
2109 State.Column = ContentStartColumn + RemainingTokenColumns -
2110 Current.UnbreakableTailLength;
2112 if (BreakInserted) {
2113 // If we break the token inside a parameter list, we need to break before
2114 // the next parameter on all levels, so that the next parameter is clearly
2115 // visible. Line comments already introduce a break.
2116 if (Current.isNot(TT_LineComment)) {
2117 for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
2118 State.Stack[i].BreakBeforeParameter = true;
2121 if (Current.is(TT_BlockComment))
2122 State.NoContinuation = true;
2124 State.Stack.back().LastSpace = StartColumn;
2127 Token->updateNextToken(State);
2129 return {Penalty, Exceeded};
2132 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2133 // In preprocessor directives reserve two chars for trailing " \"
2134 return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2137 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2138 const FormatToken &Current = *State.NextToken;
2139 if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2141 // We never consider raw string literals "multiline" for the purpose of
2142 // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2143 // (see TokenAnnotator::mustBreakBefore().
2144 if (Current.TokenText.startswith("R\""))
2146 if (Current.IsMultiline)
2148 if (Current.getNextNonComment() &&
2149 Current.getNextNonComment()->isStringLiteral())
2150 return true; // Implicit concatenation.
2151 if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2152 State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2154 return true; // String will be split.
2158 } // namespace format
2159 } // namespace clang