1 //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// This file implements the continuation indenter.
12 ///
13 //===----------------------------------------------------------------------===//
14 
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"
23 
24 #define DEBUG_TYPE "format-indenter"
25 
26 namespace clang {
27 namespace format {
28 
29 // Returns true if a TT_SelectorName should be indented when wrapped,
30 // false otherwise.
31 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
32                                             LineType LineType) {
33   return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl;
34 }
35 
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.
47   //
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.
52   //
53   // For example, consider:
54   // L. <- line number
55   // 1. {
56   // 2. {1},
57   // 3. {2},
58   // 4. {{3}}}
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}}
75   //
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)
79     return 0;
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)
89       --MatchingStackIndex;
90     return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr;
91   };
92   for (; End->Next; End = End->Next) {
93     if (End->Next->CanBreakBefore)
94       break;
95     if (!End->Next->closesScope())
96       continue;
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)
102         break;
103     }
104   }
105   return End->TotalLength - Tok.TotalLength + 1;
106 }
107 
108 static unsigned getLengthToNextOperator(const FormatToken &Tok) {
109   if (!Tok.NextOperator)
110     return 0;
111   return Tok.NextOperator->TotalLength - Tok.TotalLength;
112 }
113 
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();
118 }
119 
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)
126     return true;
127   if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName))
128     return true;
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));
135 }
136 
137 static bool opensProtoMessageField(const FormatToken &LessTok,
138                                    const FormatStyle &Style) {
139   if (LessTok.isNot(tok::less))
140     return false;
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))));
145 }
146 
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("\""))
153     return None;
154 
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
157   // 19 bytes.
158   size_t LParenPos = TokenText.substr(0, 19).find_first_of('(');
159   if (LParenPos == StringRef::npos)
160     return None;
161   StringRef Delimiter = TokenText.substr(2, LParenPos - 2);
162 
163   // Check that the string ends in ')Delimiter"'.
164   size_t RParenPos = TokenText.size() - Delimiter.size() - 2;
165   if (TokenText[RParenPos] != ')')
166     return None;
167   if (!TokenText.substr(RParenPos + 1).startswith(Delimiter))
168     return None;
169   return Delimiter;
170 }
171 
172 // Returns the canonical delimiter for \p Language, or the empty string if no
173 // canonical delimiter is specified.
174 static StringRef
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);
180   }
181   return "";
182 }
183 
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;
195       }
196       LanguageStyle = PredefinedStyle;
197     }
198     LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit;
199     for (StringRef Delimiter : RawStringFormat.Delimiters) {
200       DelimiterStyle.insert({Delimiter, *LanguageStyle});
201     }
202     for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions) {
203       EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle});
204     }
205   }
206 }
207 
208 llvm::Optional<FormatStyle>
209 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
210   auto It = DelimiterStyle.find(Delimiter);
211   if (It == DelimiterStyle.end())
212     return None;
213   return It->second;
214 }
215 
216 llvm::Optional<FormatStyle>
217 RawStringFormatStyleManager::getEnclosingFunctionStyle(
218     StringRef EnclosingFunction) const {
219   auto It = EnclosingFunctionStyle.find(EnclosingFunction);
220   if (It == EnclosingFunctionStyle.end())
221     return None;
222   return It->second;
223 }
224 
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) {}
235 
236 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent,
237                                                 unsigned FirstStartColumn,
238                                                 const AnnotatedLine *Line,
239                                                 bool DryRun) {
240   LineState State;
241   State.FirstIndent = FirstIndent;
242   if (FirstStartColumn && Line->First->NewlinesBefore == 0)
243     State.Column = FirstStartColumn;
244   else
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))
252     State.Column = 0;
253   State.Line = Line;
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;
264 
265   if (Style.Language == FormatStyle::LK_TextProto) {
266     // We need this in order to deal with the bin packing of text fields at
267     // global scope.
268     State.Stack.back().AvoidBinPacking = true;
269     State.Stack.back().BreakBeforeParameter = true;
270     State.Stack.back().AlignColons = false;
271   }
272 
273   // The first token has already been indented and thus consumed.
274   moveStateToNextToken(State, DryRun, /*Newline=*/false);
275   return State;
276 }
277 
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)))
284     return false;
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 &&
289       Previous.Previous &&
290       Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma))
291     return false;
292   // This prevents breaks like:
293   //   ...
294   //   SomeParameter, OtherParameter).DoSomething(
295   //   ...
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)
300     return false;
301   if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder)
302     return false;
303 
304   // Don't create a 'hanging' indent if there are multiple blocks in a single
305   // statement.
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)
309     return false;
310 
311   // Don't break after very short return types (e.g. "void") as that is often
312   // unexpected.
313   if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) {
314     if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None)
315       return false;
316   }
317 
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)
322     return false;
323 
324   if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr))
325     return false;
326 
327   return !State.Stack.back().NoLineBreak;
328 }
329 
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))
334     return true;
335   if (State.Stack.back().BreakBeforeClosingBrace &&
336       Current.closesBlockOrBlockTypeList(Style))
337     return true;
338   if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection)
339     return true;
340   if (Style.Language == FormatStyle::LK_ObjC &&
341       Current.ObjCSelectorNameParts > 1 &&
342       Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) {
343     return true;
344   }
345   if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
346        (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
347         Style.isCpp() &&
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
351         // line-wrapped.
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))
359     return true;
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))
367     return true;
368 
369   const FormatToken &BreakConstructorInitializersToken =
370       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon
371           ? Previous
372           : Current;
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))
380     return true;
381 
382   if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) &&
383       State.Line->startsWith(TT_ObjCMethodSpecifier))
384     return true;
385   if (Current.is(TT_SelectorName) && !Previous.is(tok::at) &&
386       State.Stack.back().ObjCSelectorNameFound &&
387       State.Stack.back().BreakBeforeParameter)
388     return true;
389 
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))
395     return true;
396 
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() {
402       //     ...
403       //   }.bind(...));
404       // FIXME: We should find a more generic solution to this problem.
405       !(State.Column <= NewLineColumn &&
406         Style.Language == FormatStyle::LK_JavaScript) &&
407       !(Previous.closesScopeAfterBlock() &&
408         State.Column <= NewLineColumn))
409     return true;
410 
411   // If the template declaration spans multiple lines, force wrap before the
412   // function/class declaration
413   if (Previous.ClosesTemplateDeclaration &&
414       State.Stack.back().BreakBeforeParameter && Current.CanBreakBefore)
415     return true;
416 
417   if (State.Column <= NewLineColumn)
418     return false;
419 
420   if (Style.AlwaysBreakBeforeMultilineStrings &&
421       (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth ||
422        Previous.is(tok::comma) || Current.NestingLevel < 2) &&
423       !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at) &&
424       !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
425       nextIsMultilineString(State))
426     return true;
427 
428   // Using CanBreakBefore here and below takes care of the decision whether the
429   // current style uses wrapping before or after operators for the given
430   // operator.
431   if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
432     // If we need to break somewhere inside the LHS of a binary expression, we
433     // should also break after the operator. Otherwise, the formatting would
434     // hide the operator precedence, e.g. in:
435     //   if (aaaaaaaaaaaaaa ==
436     //           bbbbbbbbbbbbbb && c) {..
437     // For comparisons, we only apply this rule, if the LHS is a binary
438     // expression itself as otherwise, the line breaks seem superfluous.
439     // We need special cases for ">>" which we have split into two ">" while
440     // lexing in order to make template parsing easier.
441     bool IsComparison = (Previous.getPrecedence() == prec::Relational ||
442                          Previous.getPrecedence() == prec::Equality ||
443                          Previous.getPrecedence() == prec::Spaceship) &&
444                         Previous.Previous &&
445                         Previous.Previous->isNot(TT_BinaryOperator); // For >>.
446     bool LHSIsBinaryExpr =
447         Previous.Previous && Previous.Previous->EndsBinaryExpression;
448     if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() &&
449         Previous.getPrecedence() != prec::Assignment &&
450         State.Stack.back().BreakBeforeParameter)
451       return true;
452   } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
453              State.Stack.back().BreakBeforeParameter) {
454     return true;
455   }
456 
457   // Same as above, but for the first "<<" operator.
458   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
459       State.Stack.back().BreakBeforeParameter &&
460       State.Stack.back().FirstLessLess == 0)
461     return true;
462 
463   if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
464     // Always break after "template <...>" and leading annotations. This is only
465     // for cases where the entire line does not fit on a single line as a
466     // different LineFormatter would be used otherwise.
467     if (Previous.ClosesTemplateDeclaration)
468       return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No;
469     if (Previous.is(TT_FunctionAnnotationRParen))
470       return true;
471     if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
472         Current.isNot(TT_LeadingJavaAnnotation))
473       return true;
474   }
475 
476   // If the return type spans multiple lines, wrap before the function name.
477   if ((Current.is(TT_FunctionDeclarationName) ||
478        (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) &&
479       !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter)
480     return true;
481 
482   // The following could be precomputed as they do not depend on the state.
483   // However, as they should take effect only if the UnwrappedLine does not fit
484   // into the ColumnLimit, they are checked here in the ContinuationIndenter.
485   if (Style.ColumnLimit != 0 && Previous.BlockKind == BK_Block &&
486       Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment))
487     return true;
488 
489   if (Current.is(tok::lessless) &&
490       ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
491        (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") ||
492                                      Previous.TokenText == "\'\\n\'"))))
493     return true;
494 
495   if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
496     return true;
497 
498   if (State.NoContinuation)
499     return true;
500 
501   return false;
502 }
503 
504 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
505                                                bool DryRun,
506                                                unsigned ExtraSpaces) {
507   const FormatToken &Current = *State.NextToken;
508 
509   assert(!State.Stack.empty());
510   State.NoContinuation = false;
511 
512   if ((Current.is(TT_ImplicitStringLiteral) &&
513        (Current.Previous->Tok.getIdentifierInfo() == nullptr ||
514         Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() ==
515             tok::pp_not_keyword))) {
516     unsigned EndColumn =
517         SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
518     if (Current.LastNewlineOffset != 0) {
519       // If there is a newline within this token, the final column will solely
520       // determined by the current end column.
521       State.Column = EndColumn;
522     } else {
523       unsigned StartColumn =
524           SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
525       assert(EndColumn >= StartColumn);
526       State.Column += EndColumn - StartColumn;
527     }
528     moveStateToNextToken(State, DryRun, /*Newline=*/false);
529     return 0;
530   }
531 
532   unsigned Penalty = 0;
533   if (Newline)
534     Penalty = addTokenOnNewLine(State, DryRun);
535   else
536     addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
537 
538   return moveStateToNextToken(State, DryRun, Newline) + Penalty;
539 }
540 
541 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
542                                                  unsigned ExtraSpaces) {
543   FormatToken &Current = *State.NextToken;
544   const FormatToken &Previous = *State.NextToken->Previous;
545   if (Current.is(tok::equal) &&
546       (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
547       State.Stack.back().VariablePos == 0) {
548     State.Stack.back().VariablePos = State.Column;
549     // Move over * and & if they are bound to the variable name.
550     const FormatToken *Tok = &Previous;
551     while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) {
552       State.Stack.back().VariablePos -= Tok->ColumnWidth;
553       if (Tok->SpacesRequiredBefore != 0)
554         break;
555       Tok = Tok->Previous;
556     }
557     if (Previous.PartOfMultiVariableDeclStmt)
558       State.Stack.back().LastSpace = State.Stack.back().VariablePos;
559   }
560 
561   unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
562 
563   // Indent preprocessor directives after the hash if required.
564   int PPColumnCorrection = 0;
565   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
566       Previous.is(tok::hash) && State.FirstIndent > 0 &&
567       (State.Line->Type == LT_PreprocessorDirective ||
568        State.Line->Type == LT_ImportStatement)) {
569     Spaces += State.FirstIndent;
570 
571     // For preprocessor indent with tabs, State.Column will be 1 because of the
572     // hash. This causes second-level indents onward to have an extra space
573     // after the tabs. We avoid this misalignment by subtracting 1 from the
574     // column value passed to replaceWhitespace().
575     if (Style.UseTab != FormatStyle::UT_Never)
576       PPColumnCorrection = -1;
577   }
578 
579   if (!DryRun)
580     Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
581                                   State.Column + Spaces + PPColumnCorrection);
582 
583   // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
584   // declaration unless there is multiple inheritance.
585   if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
586       Current.is(TT_InheritanceColon))
587     State.Stack.back().NoLineBreak = true;
588   if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
589       Previous.is(TT_InheritanceColon))
590     State.Stack.back().NoLineBreak = true;
591 
592   if (Current.is(TT_SelectorName) &&
593       !State.Stack.back().ObjCSelectorNameFound) {
594     unsigned MinIndent =
595         std::max(State.FirstIndent + Style.ContinuationIndentWidth,
596                  State.Stack.back().Indent);
597     unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
598     if (Current.LongestObjCSelectorName == 0)
599       State.Stack.back().AlignColons = false;
600     else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
601       State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName;
602     else
603       State.Stack.back().ColonPos = FirstColonPos;
604   }
605 
606   // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by
607   // disallowing any further line breaks if there is no line break after the
608   // opening parenthesis. Don't break if it doesn't conserve columns.
609   if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak &&
610       Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
611       State.Column > getNewLineColumn(State) &&
612       (!Previous.Previous || !Previous.Previous->isOneOf(
613                                  tok::kw_for, tok::kw_while, tok::kw_switch)) &&
614       // Don't do this for simple (no expressions) one-argument function calls
615       // as that feels like needlessly wasting whitespace, e.g.:
616       //
617       //   caaaaaaaaaaaall(
618       //       caaaaaaaaaaaall(
619       //           caaaaaaaaaaaall(
620       //               caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
621       Current.FakeLParens.size() > 0 &&
622       Current.FakeLParens.back() > prec::Unknown)
623     State.Stack.back().NoLineBreak = true;
624   if (Previous.is(TT_TemplateString) && Previous.opensScope())
625     State.Stack.back().NoLineBreak = true;
626 
627   if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
628       Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) &&
629       (Current.isNot(TT_LineComment) || Previous.BlockKind == BK_BracedInit))
630     State.Stack.back().Indent = State.Column + Spaces;
631   if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style))
632     State.Stack.back().NoLineBreak = true;
633   if (startsSegmentOfBuilderTypeCall(Current) &&
634       State.Column > getNewLineColumn(State))
635     State.Stack.back().ContainsUnwrappedBuilder = true;
636 
637   if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java)
638     State.Stack.back().NoLineBreak = true;
639   if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
640       (Previous.MatchingParen &&
641        (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10)))
642     // If there is a function call with long parameters, break before trailing
643     // calls. This prevents things like:
644     //   EXPECT_CALL(SomeLongParameter).Times(
645     //       2);
646     // We don't want to do this for short parameters as they can just be
647     // indexes.
648     State.Stack.back().NoLineBreak = true;
649 
650   // Don't allow the RHS of an operator to be split over multiple lines unless
651   // there is a line-break right after the operator.
652   // Exclude relational operators, as there, it is always more desirable to
653   // have the LHS 'left' of the RHS.
654   const FormatToken *P = Current.getPreviousNonComment();
655   if (!Current.is(tok::comment) && P &&
656       (P->isOneOf(TT_BinaryOperator, tok::comma) ||
657        (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
658       !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
659       P->getPrecedence() != prec::Assignment &&
660       P->getPrecedence() != prec::Relational &&
661       P->getPrecedence() != prec::Spaceship) {
662     bool BreakBeforeOperator =
663         P->MustBreakBefore || P->is(tok::lessless) ||
664         (P->is(TT_BinaryOperator) &&
665          Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
666         (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
667     // Don't do this if there are only two operands. In these cases, there is
668     // always a nice vertical separation between them and the extra line break
669     // does not help.
670     bool HasTwoOperands =
671         P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr);
672     if ((!BreakBeforeOperator && !(HasTwoOperands && Style.AlignOperands)) ||
673         (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator))
674       State.Stack.back().NoLineBreakInOperand = true;
675   }
676 
677   State.Column += Spaces;
678   if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
679       Previous.Previous &&
680       (Previous.Previous->isOneOf(tok::kw_if, tok::kw_for) ||
681        Previous.Previous->endsSequence(tok::kw_constexpr, tok::kw_if))) {
682     // Treat the condition inside an if as if it was a second function
683     // parameter, i.e. let nested calls have a continuation indent.
684     State.Stack.back().LastSpace = State.Column;
685     State.Stack.back().NestedBlockIndent = State.Column;
686   } else if (!Current.isOneOf(tok::comment, tok::caret) &&
687              ((Previous.is(tok::comma) &&
688                !Previous.is(TT_OverloadedOperator)) ||
689               (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
690     State.Stack.back().LastSpace = State.Column;
691   } else if (Previous.is(TT_CtorInitializerColon) &&
692              Style.BreakConstructorInitializers ==
693                  FormatStyle::BCIS_AfterColon) {
694     State.Stack.back().Indent = State.Column;
695     State.Stack.back().LastSpace = State.Column;
696   } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr,
697                                TT_CtorInitializerColon)) &&
698              ((Previous.getPrecedence() != prec::Assignment &&
699                (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
700                 Previous.NextOperator)) ||
701               Current.StartsBinaryExpression)) {
702     // Indent relative to the RHS of the expression unless this is a simple
703     // assignment without binary expression on the RHS. Also indent relative to
704     // unary operators and the colons of constructor initializers.
705     if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
706       State.Stack.back().LastSpace = State.Column;
707   } else if (Previous.is(TT_InheritanceColon)) {
708     State.Stack.back().Indent = State.Column;
709     State.Stack.back().LastSpace = State.Column;
710   } else if (Previous.opensScope()) {
711     // If a function has a trailing call, indent all parameters from the
712     // opening parenthesis. This avoids confusing indents like:
713     //   OuterFunction(InnerFunctionCall( // break
714     //       ParameterToInnerFunction))   // break
715     //       .SecondInnerFunctionCall();
716     bool HasTrailingCall = false;
717     if (Previous.MatchingParen) {
718       const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
719       HasTrailingCall = Next && Next->isMemberAccess();
720     }
721     if (HasTrailingCall && State.Stack.size() > 1 &&
722         State.Stack[State.Stack.size() - 2].CallContinuation == 0)
723       State.Stack.back().LastSpace = State.Column;
724   }
725 }
726 
727 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
728                                                  bool DryRun) {
729   FormatToken &Current = *State.NextToken;
730   const FormatToken &Previous = *State.NextToken->Previous;
731 
732   // Extra penalty that needs to be added because of the way certain line
733   // breaks are chosen.
734   unsigned Penalty = 0;
735 
736   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
737   const FormatToken *NextNonComment = Previous.getNextNonComment();
738   if (!NextNonComment)
739     NextNonComment = &Current;
740   // The first line break on any NestingLevel causes an extra penalty in order
741   // prefer similar line breaks.
742   if (!State.Stack.back().ContainsLineBreak)
743     Penalty += 15;
744   State.Stack.back().ContainsLineBreak = true;
745 
746   Penalty += State.NextToken->SplitPenalty;
747 
748   // Breaking before the first "<<" is generally not desirable if the LHS is
749   // short. Also always add the penalty if the LHS is split over multiple lines
750   // to avoid unnecessary line breaks that just work around this penalty.
751   if (NextNonComment->is(tok::lessless) &&
752       State.Stack.back().FirstLessLess == 0 &&
753       (State.Column <= Style.ColumnLimit / 3 ||
754        State.Stack.back().BreakBeforeParameter))
755     Penalty += Style.PenaltyBreakFirstLessLess;
756 
757   State.Column = getNewLineColumn(State);
758 
759   // Indent nested blocks relative to this column, unless in a very specific
760   // JavaScript special case where:
761   //
762   //   var loooooong_name =
763   //       function() {
764   //     // code
765   //   }
766   //
767   // is common and should be formatted like a free-standing function. The same
768   // goes for wrapping before the lambda return type arrow.
769   if (!Current.is(TT_LambdaArrow) &&
770       (Style.Language != FormatStyle::LK_JavaScript ||
771        Current.NestingLevel != 0 || !PreviousNonComment ||
772        !PreviousNonComment->is(tok::equal) ||
773        !Current.isOneOf(Keywords.kw_async, Keywords.kw_function)))
774     State.Stack.back().NestedBlockIndent = State.Column;
775 
776   if (NextNonComment->isMemberAccess()) {
777     if (State.Stack.back().CallContinuation == 0)
778       State.Stack.back().CallContinuation = State.Column;
779   } else if (NextNonComment->is(TT_SelectorName)) {
780     if (!State.Stack.back().ObjCSelectorNameFound) {
781       if (NextNonComment->LongestObjCSelectorName == 0) {
782         State.Stack.back().AlignColons = false;
783       } else {
784         State.Stack.back().ColonPos =
785             (shouldIndentWrappedSelectorName(Style, State.Line->Type)
786                  ? std::max(State.Stack.back().Indent,
787                             State.FirstIndent + Style.ContinuationIndentWidth)
788                  : State.Stack.back().Indent) +
789             std::max(NextNonComment->LongestObjCSelectorName,
790                      NextNonComment->ColumnWidth);
791       }
792     } else if (State.Stack.back().AlignColons &&
793                State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) {
794       State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth;
795     }
796   } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
797              PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
798     // FIXME: This is hacky, find a better way. The problem is that in an ObjC
799     // method expression, the block should be aligned to the line starting it,
800     // e.g.:
801     //   [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
802     //                        ^(int *i) {
803     //                            // ...
804     //                        }];
805     // Thus, we set LastSpace of the next higher NestingLevel, to which we move
806     // when we consume all of the "}"'s FakeRParens at the "{".
807     if (State.Stack.size() > 1)
808       State.Stack[State.Stack.size() - 2].LastSpace =
809           std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
810           Style.ContinuationIndentWidth;
811   }
812 
813   if ((PreviousNonComment &&
814        PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
815        !State.Stack.back().AvoidBinPacking) ||
816       Previous.is(TT_BinaryOperator))
817     State.Stack.back().BreakBeforeParameter = false;
818   if (PreviousNonComment &&
819       PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) &&
820       Current.NestingLevel == 0)
821     State.Stack.back().BreakBeforeParameter = false;
822   if (NextNonComment->is(tok::question) ||
823       (PreviousNonComment && PreviousNonComment->is(tok::question)))
824     State.Stack.back().BreakBeforeParameter = true;
825   if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
826     State.Stack.back().BreakBeforeParameter = false;
827 
828   if (!DryRun) {
829     unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
830     if (Current.is(tok::r_brace) && Current.MatchingParen &&
831         // Only strip trailing empty lines for l_braces that have children, i.e.
832         // for function expressions (lambdas, arrows, etc).
833         !Current.MatchingParen->Children.empty()) {
834       // lambdas and arrow functions are expressions, thus their r_brace is not
835       // on its own line, and thus not covered by UnwrappedLineFormatter's logic
836       // about removing empty lines on closing blocks. Special case them here.
837       MaxEmptyLinesToKeep = 1;
838     }
839     unsigned Newlines = std::max(
840         1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
841     bool ContinuePPDirective =
842         State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
843     Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
844                                   ContinuePPDirective);
845   }
846 
847   if (!Current.isTrailingComment())
848     State.Stack.back().LastSpace = State.Column;
849   if (Current.is(tok::lessless))
850     // If we are breaking before a "<<", we always want to indent relative to
851     // RHS. This is necessary only for "<<", as we special-case it and don't
852     // always indent relative to the RHS.
853     State.Stack.back().LastSpace += 3; // 3 -> width of "<< ".
854 
855   State.StartOfLineLevel = Current.NestingLevel;
856   State.LowestLevelOnLine = Current.NestingLevel;
857 
858   // Any break on this level means that the parent level has been broken
859   // and we need to avoid bin packing there.
860   bool NestedBlockSpecialCase =
861       !Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
862       State.Stack[State.Stack.size() - 2].NestedBlockInlined;
863   if (!NestedBlockSpecialCase)
864     for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
865       State.Stack[i].BreakBeforeParameter = true;
866 
867   if (PreviousNonComment &&
868       !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
869       (PreviousNonComment->isNot(TT_TemplateCloser) ||
870        Current.NestingLevel != 0) &&
871       !PreviousNonComment->isOneOf(
872           TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
873           TT_LeadingJavaAnnotation) &&
874       Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope())
875     State.Stack.back().BreakBeforeParameter = true;
876 
877   // If we break after { or the [ of an array initializer, we should also break
878   // before the corresponding } or ].
879   if (PreviousNonComment &&
880       (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
881        opensProtoMessageField(*PreviousNonComment, Style)))
882     State.Stack.back().BreakBeforeClosingBrace = true;
883 
884   if (State.Stack.back().AvoidBinPacking) {
885     // If we are breaking after '(', '{', '<', this is not bin packing
886     // unless AllowAllParametersOfDeclarationOnNextLine is false or this is a
887     // dict/object literal.
888     if (!Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
889         (!Style.AllowAllParametersOfDeclarationOnNextLine &&
890          State.Line->MustBeDeclaration) ||
891         Previous.is(TT_DictLiteral))
892       State.Stack.back().BreakBeforeParameter = true;
893   }
894 
895   return Penalty;
896 }
897 
898 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
899   if (!State.NextToken || !State.NextToken->Previous)
900     return 0;
901   FormatToken &Current = *State.NextToken;
902   const FormatToken &Previous = *Current.Previous;
903   // If we are continuing an expression, we want to use the continuation indent.
904   unsigned ContinuationIndent =
905       std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
906       Style.ContinuationIndentWidth;
907   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
908   const FormatToken *NextNonComment = Previous.getNextNonComment();
909   if (!NextNonComment)
910     NextNonComment = &Current;
911 
912   // Java specific bits.
913   if (Style.Language == FormatStyle::LK_Java &&
914       Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends))
915     return std::max(State.Stack.back().LastSpace,
916                     State.Stack.back().Indent + Style.ContinuationIndentWidth);
917 
918   if (NextNonComment->is(tok::l_brace) && NextNonComment->BlockKind == BK_Block)
919     return Current.NestingLevel == 0 ? State.FirstIndent
920                                      : State.Stack.back().Indent;
921   if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
922        (Current.is(tok::greater) &&
923         (Style.Language == FormatStyle::LK_Proto ||
924          Style.Language == FormatStyle::LK_TextProto))) &&
925       State.Stack.size() > 1) {
926     if (Current.closesBlockOrBlockTypeList(Style))
927       return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
928     if (Current.MatchingParen &&
929         Current.MatchingParen->BlockKind == BK_BracedInit)
930       return State.Stack[State.Stack.size() - 2].LastSpace;
931     return State.FirstIndent;
932   }
933   // Indent a closing parenthesis at the previous level if followed by a semi or
934   // opening brace. This allows indentations such as:
935   //     foo(
936   //       a,
937   //     );
938   //     function foo(
939   //       a,
940   //     ) {
941   //       code(); //
942   //     }
943   if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
944       (!Current.Next || Current.Next->isOneOf(tok::semi, tok::l_brace)))
945     return State.Stack[State.Stack.size() - 2].LastSpace;
946   if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
947     return State.Stack[State.Stack.size() - 2].LastSpace;
948   if (Current.is(tok::identifier) && Current.Next &&
949       (Current.Next->is(TT_DictLiteral) ||
950        ((Style.Language == FormatStyle::LK_Proto ||
951          Style.Language == FormatStyle::LK_TextProto) &&
952         Current.Next->isOneOf(tok::less, tok::l_brace))))
953     return State.Stack.back().Indent;
954   if (NextNonComment->is(TT_ObjCStringLiteral) &&
955       State.StartOfStringLiteral != 0)
956     return State.StartOfStringLiteral - 1;
957   if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
958     return State.StartOfStringLiteral;
959   if (NextNonComment->is(tok::lessless) &&
960       State.Stack.back().FirstLessLess != 0)
961     return State.Stack.back().FirstLessLess;
962   if (NextNonComment->isMemberAccess()) {
963     if (State.Stack.back().CallContinuation == 0)
964       return ContinuationIndent;
965     return State.Stack.back().CallContinuation;
966   }
967   if (State.Stack.back().QuestionColumn != 0 &&
968       ((NextNonComment->is(tok::colon) &&
969         NextNonComment->is(TT_ConditionalExpr)) ||
970        Previous.is(TT_ConditionalExpr)))
971     return State.Stack.back().QuestionColumn;
972   if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0)
973     return State.Stack.back().VariablePos;
974   if ((PreviousNonComment &&
975        (PreviousNonComment->ClosesTemplateDeclaration ||
976         PreviousNonComment->isOneOf(
977             TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
978             TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
979       (!Style.IndentWrappedFunctionNames &&
980        NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName)))
981     return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent);
982   if (NextNonComment->is(TT_SelectorName)) {
983     if (!State.Stack.back().ObjCSelectorNameFound) {
984       unsigned MinIndent = State.Stack.back().Indent;
985       if (shouldIndentWrappedSelectorName(Style, State.Line->Type))
986         MinIndent = std::max(MinIndent,
987                              State.FirstIndent + Style.ContinuationIndentWidth);
988       // If LongestObjCSelectorName is 0, we are indenting the first
989       // part of an ObjC selector (or a selector component which is
990       // not colon-aligned due to block formatting).
991       //
992       // Otherwise, we are indenting a subsequent part of an ObjC
993       // selector which should be colon-aligned to the longest
994       // component of the ObjC selector.
995       //
996       // In either case, we want to respect Style.IndentWrappedFunctionNames.
997       return MinIndent +
998              std::max(NextNonComment->LongestObjCSelectorName,
999                       NextNonComment->ColumnWidth) -
1000              NextNonComment->ColumnWidth;
1001     }
1002     if (!State.Stack.back().AlignColons)
1003       return State.Stack.back().Indent;
1004     if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth)
1005       return State.Stack.back().ColonPos - NextNonComment->ColumnWidth;
1006     return State.Stack.back().Indent;
1007   }
1008   if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1009     return State.Stack.back().ColonPos;
1010   if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1011     if (State.Stack.back().StartOfArraySubscripts != 0)
1012       return State.Stack.back().StartOfArraySubscripts;
1013     return ContinuationIndent;
1014   }
1015 
1016   // This ensure that we correctly format ObjC methods calls without inputs,
1017   // i.e. where the last element isn't selector like: [callee method];
1018   if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1019       NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr))
1020     return State.Stack.back().Indent;
1021 
1022   if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1023       Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon))
1024     return ContinuationIndent;
1025   if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1026       PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral))
1027     return ContinuationIndent;
1028   if (NextNonComment->is(TT_CtorInitializerComma))
1029     return State.Stack.back().Indent;
1030   if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1031       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon)
1032     return State.Stack.back().Indent;
1033   if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1034       Style.BreakInheritanceList == FormatStyle::BILS_AfterColon)
1035     return State.Stack.back().Indent;
1036   if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1037                               TT_InheritanceComma))
1038     return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1039   if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1040       !Current.isOneOf(tok::colon, tok::comment))
1041     return ContinuationIndent;
1042   if (Current.is(TT_ProtoExtensionLSquare))
1043     return State.Stack.back().Indent;
1044   if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment &&
1045       PreviousNonComment->isNot(tok::r_brace))
1046     // Ensure that we fall back to the continuation indent width instead of
1047     // just flushing continuations left.
1048     return State.Stack.back().Indent + Style.ContinuationIndentWidth;
1049   return State.Stack.back().Indent;
1050 }
1051 
1052 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1053                                                     bool DryRun, bool Newline) {
1054   assert(State.Stack.size());
1055   const FormatToken &Current = *State.NextToken;
1056 
1057   if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1058     State.Stack.back().NoLineBreakInOperand = false;
1059   if (Current.is(TT_InheritanceColon))
1060     State.Stack.back().AvoidBinPacking = true;
1061   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1062     if (State.Stack.back().FirstLessLess == 0)
1063       State.Stack.back().FirstLessLess = State.Column;
1064     else
1065       State.Stack.back().LastOperatorWrapped = Newline;
1066   }
1067   if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1068     State.Stack.back().LastOperatorWrapped = Newline;
1069   if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1070       !Current.Previous->is(TT_ConditionalExpr))
1071     State.Stack.back().LastOperatorWrapped = Newline;
1072   if (Current.is(TT_ArraySubscriptLSquare) &&
1073       State.Stack.back().StartOfArraySubscripts == 0)
1074     State.Stack.back().StartOfArraySubscripts = State.Column;
1075   if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1076     State.Stack.back().QuestionColumn = State.Column;
1077   if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1078     const FormatToken *Previous = Current.Previous;
1079     while (Previous && Previous->isTrailingComment())
1080       Previous = Previous->Previous;
1081     if (Previous && Previous->is(tok::question))
1082       State.Stack.back().QuestionColumn = State.Column;
1083   }
1084   if (!Current.opensScope() && !Current.closesScope() &&
1085       !Current.is(TT_PointerOrReference))
1086     State.LowestLevelOnLine =
1087         std::min(State.LowestLevelOnLine, Current.NestingLevel);
1088   if (Current.isMemberAccess())
1089     State.Stack.back().StartOfFunctionCall =
1090         !Current.NextOperator ? 0 : State.Column;
1091   if (Current.is(TT_SelectorName))
1092     State.Stack.back().ObjCSelectorNameFound = true;
1093   if (Current.is(TT_CtorInitializerColon) &&
1094       Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1095     // Indent 2 from the column, so:
1096     // SomeClass::SomeClass()
1097     //     : First(...), ...
1098     //       Next(...)
1099     //       ^ line up here.
1100     State.Stack.back().Indent =
1101         State.Column +
1102         (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma
1103              ? 0
1104              : 2);
1105     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1106     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1107       State.Stack.back().AvoidBinPacking = true;
1108     State.Stack.back().BreakBeforeParameter = false;
1109   }
1110   if (Current.is(TT_CtorInitializerColon) &&
1111       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1112     State.Stack.back().Indent =
1113         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1114     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1115     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1116       State.Stack.back().AvoidBinPacking = true;
1117   }
1118   if (Current.is(TT_InheritanceColon))
1119     State.Stack.back().Indent =
1120         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1121   if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1122     State.Stack.back().NestedBlockIndent =
1123         State.Column + Current.ColumnWidth + 1;
1124   if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
1125     State.Stack.back().LastSpace = State.Column;
1126 
1127   // Insert scopes created by fake parenthesis.
1128   const FormatToken *Previous = Current.getPreviousNonComment();
1129 
1130   // Add special behavior to support a format commonly used for JavaScript
1131   // closures:
1132   //   SomeFunction(function() {
1133   //     foo();
1134   //     bar();
1135   //   }, a, b, c);
1136   if (Current.isNot(tok::comment) && Previous &&
1137       Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1138       !Previous->is(TT_DictLiteral) && State.Stack.size() > 1) {
1139     if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1140       for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
1141         State.Stack[i].NoLineBreak = true;
1142     State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1143   }
1144   if (Previous &&
1145       (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) ||
1146        Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) &&
1147       !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) {
1148     State.Stack.back().NestedBlockInlined =
1149         !Newline &&
1150         (Previous->isNot(tok::l_paren) || Previous->ParameterCount > 1);
1151   }
1152 
1153   moveStatePastFakeLParens(State, Newline);
1154   moveStatePastScopeCloser(State);
1155   bool AllowBreak = !State.Stack.back().NoLineBreak &&
1156                     !State.Stack.back().NoLineBreakInOperand;
1157   moveStatePastScopeOpener(State, Newline);
1158   moveStatePastFakeRParens(State);
1159 
1160   if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1161     State.StartOfStringLiteral = State.Column + 1;
1162   else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0)
1163     State.StartOfStringLiteral = State.Column;
1164   else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1165            !Current.isStringLiteral())
1166     State.StartOfStringLiteral = 0;
1167 
1168   State.Column += Current.ColumnWidth;
1169   State.NextToken = State.NextToken->Next;
1170 
1171   unsigned Penalty =
1172       handleEndOfLine(Current, State, DryRun, AllowBreak);
1173 
1174   if (Current.Role)
1175     Current.Role->formatFromToken(State, this, DryRun);
1176   // If the previous has a special role, let it consume tokens as appropriate.
1177   // It is necessary to start at the previous token for the only implemented
1178   // role (comma separated list). That way, the decision whether or not to break
1179   // after the "{" is already done and both options are tried and evaluated.
1180   // FIXME: This is ugly, find a better way.
1181   if (Previous && Previous->Role)
1182     Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1183 
1184   return Penalty;
1185 }
1186 
1187 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1188                                                     bool Newline) {
1189   const FormatToken &Current = *State.NextToken;
1190   const FormatToken *Previous = Current.getPreviousNonComment();
1191 
1192   // Don't add extra indentation for the first fake parenthesis after
1193   // 'return', assignments or opening <({[. The indentation for these cases
1194   // is special cased.
1195   bool SkipFirstExtraIndent =
1196       (Previous && (Previous->opensScope() ||
1197                     Previous->isOneOf(tok::semi, tok::kw_return) ||
1198                     (Previous->getPrecedence() == prec::Assignment &&
1199                      Style.AlignOperands) ||
1200                     Previous->is(TT_ObjCMethodExpr)));
1201   for (SmallVectorImpl<prec::Level>::const_reverse_iterator
1202            I = Current.FakeLParens.rbegin(),
1203            E = Current.FakeLParens.rend();
1204        I != E; ++I) {
1205     ParenState NewParenState = State.Stack.back();
1206     NewParenState.Tok = nullptr;
1207     NewParenState.ContainsLineBreak = false;
1208     NewParenState.LastOperatorWrapped = true;
1209     NewParenState.NoLineBreak =
1210         NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand;
1211 
1212     // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1213     if (*I > prec::Comma)
1214       NewParenState.AvoidBinPacking = false;
1215 
1216     // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1217     // a builder type call after 'return' or, if the alignment after opening
1218     // brackets is disabled.
1219     if (!Current.isTrailingComment() &&
1220         (Style.AlignOperands || *I < prec::Assignment) &&
1221         (!Previous || Previous->isNot(tok::kw_return) ||
1222          (Style.Language != FormatStyle::LK_Java && *I > 0)) &&
1223         (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1224          *I != prec::Comma || Current.NestingLevel == 0))
1225       NewParenState.Indent =
1226           std::max(std::max(State.Column, NewParenState.Indent),
1227                    State.Stack.back().LastSpace);
1228 
1229     // Do not indent relative to the fake parentheses inserted for "." or "->".
1230     // This is a special case to make the following to statements consistent:
1231     //   OuterFunction(InnerFunctionCall( // break
1232     //       ParameterToInnerFunction));
1233     //   OuterFunction(SomeObject.InnerFunctionCall( // break
1234     //       ParameterToInnerFunction));
1235     if (*I > prec::Unknown)
1236       NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1237     if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) &&
1238         Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign)
1239       NewParenState.StartOfFunctionCall = State.Column;
1240 
1241     // Always indent conditional expressions. Never indent expression where
1242     // the 'operator' is ',', ';' or an assignment (i.e. *I <=
1243     // prec::Assignment) as those have different indentation rules. Indent
1244     // other expression, unless the indentation needs to be skipped.
1245     if (*I == prec::Conditional ||
1246         (!SkipFirstExtraIndent && *I > prec::Assignment &&
1247          !Current.isTrailingComment()))
1248       NewParenState.Indent += Style.ContinuationIndentWidth;
1249     if ((Previous && !Previous->opensScope()) || *I != prec::Comma)
1250       NewParenState.BreakBeforeParameter = false;
1251     State.Stack.push_back(NewParenState);
1252     SkipFirstExtraIndent = false;
1253   }
1254 }
1255 
1256 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1257   for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1258     unsigned VariablePos = State.Stack.back().VariablePos;
1259     if (State.Stack.size() == 1) {
1260       // Do not pop the last element.
1261       break;
1262     }
1263     State.Stack.pop_back();
1264     State.Stack.back().VariablePos = VariablePos;
1265   }
1266 }
1267 
1268 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1269                                                     bool Newline) {
1270   const FormatToken &Current = *State.NextToken;
1271   if (!Current.opensScope())
1272     return;
1273 
1274   if (Current.MatchingParen && Current.BlockKind == BK_Block) {
1275     moveStateToNewBlock(State);
1276     return;
1277   }
1278 
1279   unsigned NewIndent;
1280   unsigned LastSpace = State.Stack.back().LastSpace;
1281   bool AvoidBinPacking;
1282   bool BreakBeforeParameter = false;
1283   unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall,
1284                                         State.Stack.back().NestedBlockIndent);
1285   if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1286       opensProtoMessageField(Current, Style)) {
1287     if (Current.opensBlockOrBlockTypeList(Style)) {
1288       NewIndent = Style.IndentWidth +
1289                   std::min(State.Column, State.Stack.back().NestedBlockIndent);
1290     } else {
1291       NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth;
1292     }
1293     const FormatToken *NextNoComment = Current.getNextNonComment();
1294     bool EndsInComma = Current.MatchingParen &&
1295                        Current.MatchingParen->Previous &&
1296                        Current.MatchingParen->Previous->is(tok::comma);
1297     AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1298                       Style.Language == FormatStyle::LK_Proto ||
1299                       Style.Language == FormatStyle::LK_TextProto ||
1300                       !Style.BinPackArguments ||
1301                       (NextNoComment &&
1302                        NextNoComment->isOneOf(TT_DesignatedInitializerPeriod,
1303                                               TT_DesignatedInitializerLSquare));
1304     BreakBeforeParameter = EndsInComma;
1305     if (Current.ParameterCount > 1)
1306       NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1307   } else {
1308     NewIndent = Style.ContinuationIndentWidth +
1309                 std::max(State.Stack.back().LastSpace,
1310                          State.Stack.back().StartOfFunctionCall);
1311 
1312     // Ensure that different different brackets force relative alignment, e.g.:
1313     // void SomeFunction(vector<  // break
1314     //                       int> v);
1315     // FIXME: We likely want to do this for more combinations of brackets.
1316     if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1317       NewIndent = std::max(NewIndent, State.Stack.back().Indent);
1318       LastSpace = std::max(LastSpace, State.Stack.back().Indent);
1319     }
1320 
1321     bool EndsInComma =
1322         Current.MatchingParen &&
1323         Current.MatchingParen->getPreviousNonComment() &&
1324         Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1325 
1326     // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1327     // for backwards compatibility.
1328     bool ObjCBinPackProtocolList =
1329         (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1330          Style.BinPackParameters) ||
1331         Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1332 
1333     bool BinPackDeclaration =
1334         (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1335         (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1336 
1337     AvoidBinPacking =
1338         (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) ||
1339         (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1340         (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1341         (Style.ExperimentalAutoDetectBinPacking &&
1342          (Current.PackingKind == PPK_OnePerLine ||
1343           (!BinPackInconclusiveFunctions &&
1344            Current.PackingKind == PPK_Inconclusive)));
1345 
1346     if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen) {
1347       if (Style.ColumnLimit) {
1348         // If this '[' opens an ObjC call, determine whether all parameters fit
1349         // into one line and put one per line if they don't.
1350         if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1351             getColumnLimit(State))
1352           BreakBeforeParameter = true;
1353       } else {
1354         // For ColumnLimit = 0, we have to figure out whether there is or has to
1355         // be a line break within this call.
1356         for (const FormatToken *Tok = &Current;
1357              Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1358           if (Tok->MustBreakBefore ||
1359               (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1360             BreakBeforeParameter = true;
1361             break;
1362           }
1363         }
1364       }
1365     }
1366 
1367     if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma)
1368       BreakBeforeParameter = true;
1369   }
1370   // Generally inherit NoLineBreak from the current scope to nested scope.
1371   // However, don't do this for non-empty nested blocks, dict literals and
1372   // array literals as these follow different indentation rules.
1373   bool NoLineBreak =
1374       Current.Children.empty() &&
1375       !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1376       (State.Stack.back().NoLineBreak ||
1377        State.Stack.back().NoLineBreakInOperand ||
1378        (Current.is(TT_TemplateOpener) &&
1379         State.Stack.back().ContainsUnwrappedBuilder));
1380   State.Stack.push_back(
1381       ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1382   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1383   State.Stack.back().BreakBeforeParameter = BreakBeforeParameter;
1384   State.Stack.back().HasMultipleNestedBlocks = Current.BlockParameterCount > 1;
1385   State.Stack.back().IsInsideObjCArrayLiteral =
1386       Current.is(TT_ArrayInitializerLSquare) && Current.Previous &&
1387       Current.Previous->is(tok::at);
1388 }
1389 
1390 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1391   const FormatToken &Current = *State.NextToken;
1392   if (!Current.closesScope())
1393     return;
1394 
1395   // If we encounter a closing ), ], } or >, we can remove a level from our
1396   // stacks.
1397   if (State.Stack.size() > 1 &&
1398       (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1399        (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1400        State.NextToken->is(TT_TemplateCloser) ||
1401        (Current.is(tok::greater) && Current.is(TT_DictLiteral))))
1402     State.Stack.pop_back();
1403 
1404   // Reevaluate whether ObjC message arguments fit into one line.
1405   // If a receiver spans multiple lines, e.g.:
1406   //   [[object block:^{
1407   //     return 42;
1408   //   }] a:42 b:42];
1409   // BreakBeforeParameter is calculated based on an incorrect assumption
1410   // (it is checked whether the whole expression fits into one line without
1411   // considering a line break inside a message receiver).
1412   // We check whether arguements fit after receiver scope closer (into the same
1413   // line).
1414   if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen &&
1415       Current.MatchingParen->Previous) {
1416     const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1417     if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1418         CurrentScopeOpener.MatchingParen) {
1419       int NecessarySpaceInLine =
1420           getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1421           CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1422       if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1423           Style.ColumnLimit)
1424         State.Stack.back().BreakBeforeParameter = false;
1425     }
1426   }
1427 
1428   if (Current.is(tok::r_square)) {
1429     // If this ends the array subscript expr, reset the corresponding value.
1430     const FormatToken *NextNonComment = Current.getNextNonComment();
1431     if (NextNonComment && NextNonComment->isNot(tok::l_square))
1432       State.Stack.back().StartOfArraySubscripts = 0;
1433   }
1434 }
1435 
1436 void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1437   unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1438   // ObjC block sometimes follow special indentation rules.
1439   unsigned NewIndent =
1440       NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1441                                ? Style.ObjCBlockIndentWidth
1442                                : Style.IndentWidth);
1443   State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1444                                    State.Stack.back().LastSpace,
1445                                    /*AvoidBinPacking=*/true,
1446                                    /*NoLineBreak=*/false));
1447   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1448   State.Stack.back().BreakBeforeParameter = true;
1449 }
1450 
1451 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1452                                      unsigned TabWidth,
1453                                      encoding::Encoding Encoding) {
1454   size_t LastNewlinePos = Text.find_last_of("\n");
1455   if (LastNewlinePos == StringRef::npos) {
1456     return StartColumn +
1457            encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
1458   } else {
1459     return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
1460                                          /*StartColumn=*/0, TabWidth, Encoding);
1461   }
1462 }
1463 
1464 unsigned ContinuationIndenter::reformatRawStringLiteral(
1465     const FormatToken &Current, LineState &State,
1466     const FormatStyle &RawStringStyle, bool DryRun) {
1467   unsigned StartColumn = State.Column - Current.ColumnWidth;
1468   StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
1469   StringRef NewDelimiter =
1470       getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
1471   if (NewDelimiter.empty() || OldDelimiter.empty())
1472     NewDelimiter = OldDelimiter;
1473   // The text of a raw string is between the leading 'R"delimiter(' and the
1474   // trailing 'delimiter)"'.
1475   unsigned OldPrefixSize = 3 + OldDelimiter.size();
1476   unsigned OldSuffixSize = 2 + OldDelimiter.size();
1477   // We create a virtual text environment which expects a null-terminated
1478   // string, so we cannot use StringRef.
1479   std::string RawText =
1480       Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize);
1481   if (NewDelimiter != OldDelimiter) {
1482     // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
1483     // raw string.
1484     std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
1485     if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
1486       NewDelimiter = OldDelimiter;
1487   }
1488 
1489   unsigned NewPrefixSize = 3 + NewDelimiter.size();
1490   unsigned NewSuffixSize = 2 + NewDelimiter.size();
1491 
1492   // The first start column is the column the raw text starts after formatting.
1493   unsigned FirstStartColumn = StartColumn + NewPrefixSize;
1494 
1495   // The next start column is the intended indentation a line break inside
1496   // the raw string at level 0. It is determined by the following rules:
1497   //   - if the content starts on newline, it is one level more than the current
1498   //     indent, and
1499   //   - if the content does not start on a newline, it is the first start
1500   //     column.
1501   // These rules have the advantage that the formatted content both does not
1502   // violate the rectangle rule and visually flows within the surrounding
1503   // source.
1504   bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
1505   unsigned NextStartColumn =
1506       ContentStartsOnNewline
1507           ? State.Stack.back().NestedBlockIndent + Style.IndentWidth
1508           : FirstStartColumn;
1509 
1510   // The last start column is the column the raw string suffix starts if it is
1511   // put on a newline.
1512   // The last start column is the intended indentation of the raw string postfix
1513   // if it is put on a newline. It is determined by the following rules:
1514   //   - if the raw string prefix starts on a newline, it is the column where
1515   //     that raw string prefix starts, and
1516   //   - if the raw string prefix does not start on a newline, it is the current
1517   //     indent.
1518   unsigned LastStartColumn = Current.NewlinesBefore
1519                                  ? FirstStartColumn - NewPrefixSize
1520                                  : State.Stack.back().NestedBlockIndent;
1521 
1522   std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
1523       RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
1524       FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
1525       /*Status=*/nullptr);
1526 
1527   auto NewCode = applyAllReplacements(RawText, Fixes.first);
1528   tooling::Replacements NoFixes;
1529   if (!NewCode) {
1530     State.Column += Current.ColumnWidth;
1531     return 0;
1532   }
1533   if (!DryRun) {
1534     if (NewDelimiter != OldDelimiter) {
1535       // In 'R"delimiter(...', the delimiter starts 2 characters after the start
1536       // of the token.
1537       SourceLocation PrefixDelimiterStart =
1538           Current.Tok.getLocation().getLocWithOffset(2);
1539       auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
1540           SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1541       if (PrefixErr) {
1542         llvm::errs()
1543             << "Failed to update the prefix delimiter of a raw string: "
1544             << llvm::toString(std::move(PrefixErr)) << "\n";
1545       }
1546       // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
1547       // position length - 1 - |delimiter|.
1548       SourceLocation SuffixDelimiterStart =
1549           Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
1550                                                      1 - OldDelimiter.size());
1551       auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
1552           SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1553       if (SuffixErr) {
1554         llvm::errs()
1555             << "Failed to update the suffix delimiter of a raw string: "
1556             << llvm::toString(std::move(SuffixErr)) << "\n";
1557       }
1558     }
1559     SourceLocation OriginLoc =
1560         Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
1561     for (const tooling::Replacement &Fix : Fixes.first) {
1562       auto Err = Whitespaces.addReplacement(tooling::Replacement(
1563           SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
1564           Fix.getLength(), Fix.getReplacementText()));
1565       if (Err) {
1566         llvm::errs() << "Failed to reformat raw string: "
1567                      << llvm::toString(std::move(Err)) << "\n";
1568       }
1569     }
1570   }
1571   unsigned RawLastLineEndColumn = getLastLineEndColumn(
1572       *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
1573   State.Column = RawLastLineEndColumn + NewSuffixSize;
1574   // Since we're updating the column to after the raw string literal here, we
1575   // have to manually add the penalty for the prefix R"delim( over the column
1576   // limit.
1577   unsigned PrefixExcessCharacters =
1578       StartColumn + NewPrefixSize > Style.ColumnLimit ?
1579       StartColumn + NewPrefixSize - Style.ColumnLimit : 0;
1580   return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
1581 }
1582 
1583 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
1584                                                  LineState &State) {
1585   // Break before further function parameters on all levels.
1586   for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1587     State.Stack[i].BreakBeforeParameter = true;
1588 
1589   unsigned ColumnsUsed = State.Column;
1590   // We can only affect layout of the first and the last line, so the penalty
1591   // for all other lines is constant, and we ignore it.
1592   State.Column = Current.LastLineColumnWidth;
1593 
1594   if (ColumnsUsed > getColumnLimit(State))
1595     return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
1596   return 0;
1597 }
1598 
1599 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
1600                                                LineState &State, bool DryRun,
1601                                                bool AllowBreak) {
1602   unsigned Penalty = 0;
1603   // Compute the raw string style to use in case this is a raw string literal
1604   // that can be reformatted.
1605   auto RawStringStyle = getRawStringStyle(Current, State);
1606   if (RawStringStyle && !Current.Finalized) {
1607     Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun);
1608   } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
1609     // Don't break multi-line tokens other than block comments and raw string
1610     // literals. Instead, just update the state.
1611     Penalty = addMultilineToken(Current, State);
1612   } else if (State.Line->Type != LT_ImportStatement) {
1613     // We generally don't break import statements.
1614     LineState OriginalState = State;
1615 
1616     // Whether we force the reflowing algorithm to stay strictly within the
1617     // column limit.
1618     bool Strict = false;
1619     // Whether the first non-strict attempt at reflowing did intentionally
1620     // exceed the column limit.
1621     bool Exceeded = false;
1622     std::tie(Penalty, Exceeded) = breakProtrudingToken(
1623         Current, State, AllowBreak, /*DryRun=*/true, Strict);
1624     if (Exceeded) {
1625       // If non-strict reflowing exceeds the column limit, try whether strict
1626       // reflowing leads to an overall lower penalty.
1627       LineState StrictState = OriginalState;
1628       unsigned StrictPenalty =
1629           breakProtrudingToken(Current, StrictState, AllowBreak,
1630                                /*DryRun=*/true, /*Strict=*/true)
1631               .first;
1632       Strict = StrictPenalty <= Penalty;
1633       if (Strict) {
1634         Penalty = StrictPenalty;
1635         State = StrictState;
1636       }
1637     }
1638     if (!DryRun) {
1639       // If we're not in dry-run mode, apply the changes with the decision on
1640       // strictness made above.
1641       breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
1642                            Strict);
1643     }
1644   }
1645   if (State.Column > getColumnLimit(State)) {
1646     unsigned ExcessCharacters = State.Column - getColumnLimit(State);
1647     Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
1648   }
1649   return Penalty;
1650 }
1651 
1652 // Returns the enclosing function name of a token, or the empty string if not
1653 // found.
1654 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
1655   // Look for: 'function(' or 'function<templates>(' before Current.
1656   auto Tok = Current.getPreviousNonComment();
1657   if (!Tok || !Tok->is(tok::l_paren))
1658     return "";
1659   Tok = Tok->getPreviousNonComment();
1660   if (!Tok)
1661     return "";
1662   if (Tok->is(TT_TemplateCloser)) {
1663     Tok = Tok->MatchingParen;
1664     if (Tok)
1665       Tok = Tok->getPreviousNonComment();
1666   }
1667   if (!Tok || !Tok->is(tok::identifier))
1668     return "";
1669   return Tok->TokenText;
1670 }
1671 
1672 llvm::Optional<FormatStyle>
1673 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
1674                                         const LineState &State) {
1675   if (!Current.isStringLiteral())
1676     return None;
1677   auto Delimiter = getRawStringDelimiter(Current.TokenText);
1678   if (!Delimiter)
1679     return None;
1680   auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
1681   if (!RawStringStyle && Delimiter->empty())
1682     RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
1683         getEnclosingFunctionName(Current));
1684   if (!RawStringStyle)
1685     return None;
1686   RawStringStyle->ColumnLimit = getColumnLimit(State);
1687   return RawStringStyle;
1688 }
1689 
1690 std::unique_ptr<BreakableToken> ContinuationIndenter::createBreakableToken(
1691     const FormatToken &Current, LineState &State, bool AllowBreak) {
1692   unsigned StartColumn = State.Column - Current.ColumnWidth;
1693   if (Current.isStringLiteral()) {
1694     // FIXME: String literal breaking is currently disabled for Java and JS, as
1695     // it requires strings to be merged using "+" which we don't support.
1696     if (Style.Language == FormatStyle::LK_Java ||
1697         Style.Language == FormatStyle::LK_JavaScript ||
1698         !Style.BreakStringLiterals ||
1699         !AllowBreak)
1700       return nullptr;
1701 
1702     // Don't break string literals inside preprocessor directives (except for
1703     // #define directives, as their contents are stored in separate lines and
1704     // are not affected by this check).
1705     // This way we avoid breaking code with line directives and unknown
1706     // preprocessor directives that contain long string literals.
1707     if (State.Line->Type == LT_PreprocessorDirective)
1708       return nullptr;
1709     // Exempts unterminated string literals from line breaking. The user will
1710     // likely want to terminate the string before any line breaking is done.
1711     if (Current.IsUnterminatedLiteral)
1712       return nullptr;
1713     // Don't break string literals inside Objective-C array literals (doing so
1714     // raises the warning -Wobjc-string-concatenation).
1715     if (State.Stack.back().IsInsideObjCArrayLiteral) {
1716       return nullptr;
1717     }
1718 
1719     StringRef Text = Current.TokenText;
1720     StringRef Prefix;
1721     StringRef Postfix;
1722     // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
1723     // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
1724     // reduce the overhead) for each FormatToken, which is a string, so that we
1725     // don't run multiple checks here on the hot path.
1726     if ((Text.endswith(Postfix = "\"") &&
1727          (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") ||
1728           Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") ||
1729           Text.startswith(Prefix = "u8\"") ||
1730           Text.startswith(Prefix = "L\""))) ||
1731         (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) {
1732       // We need this to address the case where there is an unbreakable tail
1733       // only if certain other formatting decisions have been taken. The
1734       // UnbreakableTailLength of Current is an overapproximation is that case
1735       // and we need to be correct here.
1736       unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
1737                                            ? 0
1738                                            : Current.UnbreakableTailLength;
1739       return llvm::make_unique<BreakableStringLiteral>(
1740           Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
1741           State.Line->InPPDirective, Encoding, Style);
1742     }
1743   } else if (Current.is(TT_BlockComment)) {
1744     if (!Style.ReflowComments ||
1745         // If a comment token switches formatting, like
1746         // /* clang-format on */, we don't want to break it further,
1747         // but we may still want to adjust its indentation.
1748         switchesFormatting(Current)) {
1749       return nullptr;
1750     }
1751     return llvm::make_unique<BreakableBlockComment>(
1752         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1753         State.Line->InPPDirective, Encoding, Style);
1754   } else if (Current.is(TT_LineComment) &&
1755              (Current.Previous == nullptr ||
1756               Current.Previous->isNot(TT_ImplicitStringLiteral))) {
1757     if (!Style.ReflowComments ||
1758         CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
1759         switchesFormatting(Current))
1760       return nullptr;
1761     return llvm::make_unique<BreakableLineCommentSection>(
1762         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1763         /*InPPDirective=*/false, Encoding, Style);
1764   }
1765   return nullptr;
1766 }
1767 
1768 std::pair<unsigned, bool>
1769 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
1770                                            LineState &State, bool AllowBreak,
1771                                            bool DryRun, bool Strict) {
1772   std::unique_ptr<const BreakableToken> Token =
1773       createBreakableToken(Current, State, AllowBreak);
1774   if (!Token)
1775     return {0, false};
1776   assert(Token->getLineCount() > 0);
1777   unsigned ColumnLimit = getColumnLimit(State);
1778   if (Current.is(TT_LineComment)) {
1779     // We don't insert backslashes when breaking line comments.
1780     ColumnLimit = Style.ColumnLimit;
1781   }
1782   if (Current.UnbreakableTailLength >= ColumnLimit)
1783     return {0, false};
1784   // ColumnWidth was already accounted into State.Column before calling
1785   // breakProtrudingToken.
1786   unsigned StartColumn = State.Column - Current.ColumnWidth;
1787   unsigned NewBreakPenalty = Current.isStringLiteral()
1788                                  ? Style.PenaltyBreakString
1789                                  : Style.PenaltyBreakComment;
1790   // Stores whether we intentionally decide to let a line exceed the column
1791   // limit.
1792   bool Exceeded = false;
1793   // Stores whether we introduce a break anywhere in the token.
1794   bool BreakInserted = Token->introducesBreakBeforeToken();
1795   // Store whether we inserted a new line break at the end of the previous
1796   // logical line.
1797   bool NewBreakBefore = false;
1798   // We use a conservative reflowing strategy. Reflow starts after a line is
1799   // broken or the corresponding whitespace compressed. Reflow ends as soon as a
1800   // line that doesn't get reflown with the previous line is reached.
1801   bool Reflow = false;
1802   // Keep track of where we are in the token:
1803   // Where we are in the content of the current logical line.
1804   unsigned TailOffset = 0;
1805   // The column number we're currently at.
1806   unsigned ContentStartColumn =
1807       Token->getContentStartColumn(0, /*Break=*/false);
1808   // The number of columns left in the current logical line after TailOffset.
1809   unsigned RemainingTokenColumns =
1810       Token->getRemainingLength(0, TailOffset, ContentStartColumn);
1811   // Adapt the start of the token, for example indent.
1812   if (!DryRun)
1813     Token->adaptStartOfLine(0, Whitespaces);
1814 
1815   unsigned ContentIndent = 0;
1816   unsigned Penalty = 0;
1817   LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
1818                           << StartColumn << ".\n");
1819   for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
1820        LineIndex != EndIndex; ++LineIndex) {
1821     LLVM_DEBUG(llvm::dbgs()
1822                << "  Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
1823     NewBreakBefore = false;
1824     // If we did reflow the previous line, we'll try reflowing again. Otherwise
1825     // we'll start reflowing if the current line is broken or whitespace is
1826     // compressed.
1827     bool TryReflow = Reflow;
1828     // Break the current token until we can fit the rest of the line.
1829     while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
1830       LLVM_DEBUG(llvm::dbgs() << "    Over limit, need: "
1831                               << (ContentStartColumn + RemainingTokenColumns)
1832                               << ", space: " << ColumnLimit
1833                               << ", reflown prefix: " << ContentStartColumn
1834                               << ", offset in line: " << TailOffset << "\n");
1835       // If the current token doesn't fit, find the latest possible split in the
1836       // current line so that breaking at it will be under the column limit.
1837       // FIXME: Use the earliest possible split while reflowing to correctly
1838       // compress whitespace within a line.
1839       BreakableToken::Split Split =
1840           Token->getSplit(LineIndex, TailOffset, ColumnLimit,
1841                           ContentStartColumn, CommentPragmasRegex);
1842       if (Split.first == StringRef::npos) {
1843         // No break opportunity - update the penalty and continue with the next
1844         // logical line.
1845         if (LineIndex < EndIndex - 1)
1846           // The last line's penalty is handled in addNextStateToQueue() or when
1847           // calling replaceWhitespaceAfterLastLine below.
1848           Penalty += Style.PenaltyExcessCharacter *
1849                      (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
1850         LLVM_DEBUG(llvm::dbgs() << "    No break opportunity.\n");
1851         break;
1852       }
1853       assert(Split.first != 0);
1854 
1855       if (Token->supportsReflow()) {
1856         // Check whether the next natural split point after the current one can
1857         // still fit the line, either because we can compress away whitespace,
1858         // or because the penalty the excess characters introduce is lower than
1859         // the break penalty.
1860         // We only do this for tokens that support reflowing, and thus allow us
1861         // to change the whitespace arbitrarily (e.g. comments).
1862         // Other tokens, like string literals, can be broken on arbitrary
1863         // positions.
1864 
1865         // First, compute the columns from TailOffset to the next possible split
1866         // position.
1867         // For example:
1868         // ColumnLimit:     |
1869         // // Some text   that    breaks
1870         //    ^ tail offset
1871         //             ^-- split
1872         //    ^-------- to split columns
1873         //                    ^--- next split
1874         //    ^--------------- to next split columns
1875         unsigned ToSplitColumns = Token->getRangeLength(
1876             LineIndex, TailOffset, Split.first, ContentStartColumn);
1877         LLVM_DEBUG(llvm::dbgs() << "    ToSplit: " << ToSplitColumns << "\n");
1878 
1879         BreakableToken::Split NextSplit = Token->getSplit(
1880             LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
1881             ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
1882         // Compute the columns necessary to fit the next non-breakable sequence
1883         // into the current line.
1884         unsigned ToNextSplitColumns = 0;
1885         if (NextSplit.first == StringRef::npos) {
1886           ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
1887                                                          ContentStartColumn);
1888         } else {
1889           ToNextSplitColumns = Token->getRangeLength(
1890               LineIndex, TailOffset,
1891               Split.first + Split.second + NextSplit.first, ContentStartColumn);
1892         }
1893         // Compress the whitespace between the break and the start of the next
1894         // unbreakable sequence.
1895         ToNextSplitColumns =
1896             Token->getLengthAfterCompression(ToNextSplitColumns, Split);
1897         LLVM_DEBUG(llvm::dbgs()
1898                    << "    ContentStartColumn: " << ContentStartColumn << "\n");
1899         LLVM_DEBUG(llvm::dbgs()
1900                    << "    ToNextSplit: " << ToNextSplitColumns << "\n");
1901         // If the whitespace compression makes us fit, continue on the current
1902         // line.
1903         bool ContinueOnLine =
1904             ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
1905         unsigned ExcessCharactersPenalty = 0;
1906         if (!ContinueOnLine && !Strict) {
1907           // Similarly, if the excess characters' penalty is lower than the
1908           // penalty of introducing a new break, continue on the current line.
1909           ExcessCharactersPenalty =
1910               (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
1911               Style.PenaltyExcessCharacter;
1912           LLVM_DEBUG(llvm::dbgs()
1913                      << "    Penalty excess: " << ExcessCharactersPenalty
1914                      << "\n            break : " << NewBreakPenalty << "\n");
1915           if (ExcessCharactersPenalty < NewBreakPenalty) {
1916             Exceeded = true;
1917             ContinueOnLine = true;
1918           }
1919         }
1920         if (ContinueOnLine) {
1921           LLVM_DEBUG(llvm::dbgs() << "    Continuing on line...\n");
1922           // The current line fits after compressing the whitespace - reflow
1923           // the next line into it if possible.
1924           TryReflow = true;
1925           if (!DryRun)
1926             Token->compressWhitespace(LineIndex, TailOffset, Split,
1927                                       Whitespaces);
1928           // When we continue on the same line, leave one space between content.
1929           ContentStartColumn += ToSplitColumns + 1;
1930           Penalty += ExcessCharactersPenalty;
1931           TailOffset += Split.first + Split.second;
1932           RemainingTokenColumns = Token->getRemainingLength(
1933               LineIndex, TailOffset, ContentStartColumn);
1934           continue;
1935         }
1936       }
1937       LLVM_DEBUG(llvm::dbgs() << "    Breaking...\n");
1938       // Update the ContentIndent only if the current line was not reflown with
1939       // the previous line, since in that case the previous line should still
1940       // determine the ContentIndent. Also never intent the last line.
1941       if (!Reflow)
1942         ContentIndent = Token->getContentIndent(LineIndex);
1943       LLVM_DEBUG(llvm::dbgs()
1944                  << "    ContentIndent: " << ContentIndent << "\n");
1945       ContentStartColumn = ContentIndent + Token->getContentStartColumn(
1946                                                LineIndex, /*Break=*/true);
1947 
1948       unsigned NewRemainingTokenColumns = Token->getRemainingLength(
1949           LineIndex, TailOffset + Split.first + Split.second,
1950           ContentStartColumn);
1951       if (NewRemainingTokenColumns == 0) {
1952         // No content to indent.
1953         ContentIndent = 0;
1954         ContentStartColumn =
1955             Token->getContentStartColumn(LineIndex, /*Break=*/true);
1956         NewRemainingTokenColumns = Token->getRemainingLength(
1957             LineIndex, TailOffset + Split.first + Split.second,
1958             ContentStartColumn);
1959       }
1960 
1961       // When breaking before a tab character, it may be moved by a few columns,
1962       // but will still be expanded to the next tab stop, so we don't save any
1963       // columns.
1964       if (NewRemainingTokenColumns == RemainingTokenColumns) {
1965         // FIXME: Do we need to adjust the penalty?
1966         break;
1967       }
1968       assert(NewRemainingTokenColumns < RemainingTokenColumns);
1969 
1970       LLVM_DEBUG(llvm::dbgs() << "    Breaking at: " << TailOffset + Split.first
1971                               << ", " << Split.second << "\n");
1972       if (!DryRun)
1973         Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
1974                            Whitespaces);
1975 
1976       Penalty += NewBreakPenalty;
1977       TailOffset += Split.first + Split.second;
1978       RemainingTokenColumns = NewRemainingTokenColumns;
1979       BreakInserted = true;
1980       NewBreakBefore = true;
1981     }
1982     // In case there's another line, prepare the state for the start of the next
1983     // line.
1984     if (LineIndex + 1 != EndIndex) {
1985       unsigned NextLineIndex = LineIndex + 1;
1986       if (NewBreakBefore)
1987         // After breaking a line, try to reflow the next line into the current
1988         // one once RemainingTokenColumns fits.
1989         TryReflow = true;
1990       if (TryReflow) {
1991         // We decided that we want to try reflowing the next line into the
1992         // current one.
1993         // We will now adjust the state as if the reflow is successful (in
1994         // preparation for the next line), and see whether that works. If we
1995         // decide that we cannot reflow, we will later reset the state to the
1996         // start of the next line.
1997         Reflow = false;
1998         // As we did not continue breaking the line, RemainingTokenColumns is
1999         // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2000         // the position at which we want to format the next line if we do
2001         // actually reflow.
2002         // When we reflow, we need to add a space between the end of the current
2003         // line and the next line's start column.
2004         ContentStartColumn += RemainingTokenColumns + 1;
2005         // Get the split that we need to reflow next logical line into the end
2006         // of the current one; the split will include any leading whitespace of
2007         // the next logical line.
2008         BreakableToken::Split SplitBeforeNext =
2009             Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2010         LLVM_DEBUG(llvm::dbgs()
2011                    << "    Size of reflown text: " << ContentStartColumn
2012                    << "\n    Potential reflow split: ");
2013         if (SplitBeforeNext.first != StringRef::npos) {
2014           LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2015                                   << SplitBeforeNext.second << "\n");
2016           TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2017           // If the rest of the next line fits into the current line below the
2018           // column limit, we can safely reflow.
2019           RemainingTokenColumns = Token->getRemainingLength(
2020               NextLineIndex, TailOffset, ContentStartColumn);
2021           Reflow = true;
2022           if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2023             LLVM_DEBUG(llvm::dbgs()
2024                        << "    Over limit after reflow, need: "
2025                        << (ContentStartColumn + RemainingTokenColumns)
2026                        << ", space: " << ColumnLimit
2027                        << ", reflown prefix: " << ContentStartColumn
2028                        << ", offset in line: " << TailOffset << "\n");
2029             // If the whole next line does not fit, try to find a point in
2030             // the next line at which we can break so that attaching the part
2031             // of the next line to that break point onto the current line is
2032             // below the column limit.
2033             BreakableToken::Split Split =
2034                 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2035                                 ContentStartColumn, CommentPragmasRegex);
2036             if (Split.first == StringRef::npos) {
2037               LLVM_DEBUG(llvm::dbgs() << "    Did not find later break\n");
2038               Reflow = false;
2039             } else {
2040               // Check whether the first split point gets us below the column
2041               // limit. Note that we will execute this split below as part of
2042               // the normal token breaking and reflow logic within the line.
2043               unsigned ToSplitColumns = Token->getRangeLength(
2044                   NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2045               if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2046                 LLVM_DEBUG(llvm::dbgs() << "    Next split protrudes, need: "
2047                                         << (ContentStartColumn + ToSplitColumns)
2048                                         << ", space: " << ColumnLimit);
2049                 unsigned ExcessCharactersPenalty =
2050                     (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2051                     Style.PenaltyExcessCharacter;
2052                 if (NewBreakPenalty < ExcessCharactersPenalty) {
2053                   Reflow = false;
2054                 }
2055               }
2056             }
2057           }
2058         } else {
2059           LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2060         }
2061       }
2062       if (!Reflow) {
2063         // If we didn't reflow into the next line, the only space to consider is
2064         // the next logical line. Reset our state to match the start of the next
2065         // line.
2066         TailOffset = 0;
2067         ContentStartColumn =
2068             Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2069         RemainingTokenColumns = Token->getRemainingLength(
2070             NextLineIndex, TailOffset, ContentStartColumn);
2071         // Adapt the start of the token, for example indent.
2072         if (!DryRun)
2073           Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2074       } else {
2075         // If we found a reflow split and have added a new break before the next
2076         // line, we are going to remove the line break at the start of the next
2077         // logical line. For example, here we'll add a new line break after
2078         // 'text', and subsequently delete the line break between 'that' and
2079         // 'reflows'.
2080         //   // some text that
2081         //   // reflows
2082         // ->
2083         //   // some text
2084         //   // that reflows
2085         // When adding the line break, we also added the penalty for it, so we
2086         // need to subtract that penalty again when we remove the line break due
2087         // to reflowing.
2088         if (NewBreakBefore) {
2089           assert(Penalty >= NewBreakPenalty);
2090           Penalty -= NewBreakPenalty;
2091         }
2092         if (!DryRun)
2093           Token->reflow(NextLineIndex, Whitespaces);
2094       }
2095     }
2096   }
2097 
2098   BreakableToken::Split SplitAfterLastLine =
2099       Token->getSplitAfterLastLine(TailOffset);
2100   if (SplitAfterLastLine.first != StringRef::npos) {
2101     LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2102 
2103     // We add the last line's penalty here, since that line is going to be split
2104     // now.
2105     Penalty += Style.PenaltyExcessCharacter *
2106                (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2107 
2108     if (!DryRun)
2109       Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2110                                             Whitespaces);
2111     ContentStartColumn =
2112         Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2113     RemainingTokenColumns = Token->getRemainingLength(
2114         Token->getLineCount() - 1,
2115         TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2116         ContentStartColumn);
2117   }
2118 
2119   State.Column = ContentStartColumn + RemainingTokenColumns -
2120                  Current.UnbreakableTailLength;
2121 
2122   if (BreakInserted) {
2123     // If we break the token inside a parameter list, we need to break before
2124     // the next parameter on all levels, so that the next parameter is clearly
2125     // visible. Line comments already introduce a break.
2126     if (Current.isNot(TT_LineComment)) {
2127       for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
2128         State.Stack[i].BreakBeforeParameter = true;
2129     }
2130 
2131     if (Current.is(TT_BlockComment))
2132       State.NoContinuation = true;
2133 
2134     State.Stack.back().LastSpace = StartColumn;
2135   }
2136 
2137   Token->updateNextToken(State);
2138 
2139   return {Penalty, Exceeded};
2140 }
2141 
2142 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2143   // In preprocessor directives reserve two chars for trailing " \"
2144   return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2145 }
2146 
2147 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2148   const FormatToken &Current = *State.NextToken;
2149   if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2150     return false;
2151   // We never consider raw string literals "multiline" for the purpose of
2152   // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2153   // (see TokenAnnotator::mustBreakBefore().
2154   if (Current.TokenText.startswith("R\""))
2155     return false;
2156   if (Current.IsMultiline)
2157     return true;
2158   if (Current.getNextNonComment() &&
2159       Current.getNextNonComment()->isStringLiteral())
2160     return true; // Implicit concatenation.
2161   if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2162       State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2163           Style.ColumnLimit)
2164     return true; // String will be split.
2165   return false;
2166 }
2167 
2168 } // namespace format
2169 } // namespace clang
2170