1 //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file implements the continuation indenter.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "ContinuationIndenter.h"
15 #include "BreakableToken.h"
16 #include "FormatInternal.h"
17 #include "WhitespaceManager.h"
18 #include "clang/Basic/OperatorPrecedence.h"
19 #include "clang/Basic/SourceManager.h"
20 #include "clang/Format/Format.h"
21 #include "llvm/Support/Debug.h"
22 
23 #define DEBUG_TYPE "format-indenter"
24 
25 namespace clang {
26 namespace format {
27 
28 // Returns true if a TT_SelectorName should be indented when wrapped,
29 // false otherwise.
30 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
31                                             LineType LineType) {
32   return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl;
33 }
34 
35 // Returns the length of everything up to the first possible line break after
36 // the ), ], } or > matching \c Tok.
37 static unsigned getLengthToMatchingParen(const FormatToken &Tok,
38                                          const std::vector<ParenState> &Stack) {
39   // Normally whether or not a break before T is possible is calculated and
40   // stored in T.CanBreakBefore. Braces, array initializers and text proto
41   // messages like `key: < ... >` are an exception: a break is possible
42   // before a closing brace R if a break was inserted after the corresponding
43   // opening brace. The information about whether or not a break is needed
44   // before a closing brace R is stored in the ParenState field
45   // S.BreakBeforeClosingBrace where S is the state that R closes.
46   //
47   // In order to decide whether there can be a break before encountered right
48   // braces, this implementation iterates over the sequence of tokens and over
49   // the paren stack in lockstep, keeping track of the stack level which visited
50   // right braces correspond to in MatchingStackIndex.
51   //
52   // For example, consider:
53   // L. <- line number
54   // 1. {
55   // 2. {1},
56   // 3. {2},
57   // 4. {{3}}}
58   //     ^ where we call this method with this token.
59   // The paren stack at this point contains 3 brace levels:
60   //  0. { at line 1, BreakBeforeClosingBrace: true
61   //  1. first { at line 4, BreakBeforeClosingBrace: false
62   //  2. second { at line 4, BreakBeforeClosingBrace: false,
63   //  where there might be fake parens levels in-between these levels.
64   // The algorithm will start at the first } on line 4, which is the matching
65   // brace of the initial left brace and at level 2 of the stack. Then,
66   // examining BreakBeforeClosingBrace: false at level 2, it will continue to
67   // the second } on line 4, and will traverse the stack downwards until it
68   // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace:
69   // false at level 1, it will continue to the third } on line 4 and will
70   // traverse the stack downwards until it finds the matching { on level 0.
71   // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm
72   // will stop and will use the second } on line 4 to determine the length to
73   // return, as in this example the range will include the tokens: {3}}
74   //
75   // The algorithm will only traverse the stack if it encounters braces, array
76   // initializer squares or text proto angle brackets.
77   if (!Tok.MatchingParen)
78     return 0;
79   FormatToken *End = Tok.MatchingParen;
80   // Maintains a stack level corresponding to the current End token.
81   int MatchingStackIndex = Stack.size() - 1;
82   // Traverses the stack downwards, looking for the level to which LBrace
83   // corresponds. Returns either a pointer to the matching level or nullptr if
84   // LParen is not found in the initial portion of the stack up to
85   // MatchingStackIndex.
86   auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * {
87     while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace)
88       --MatchingStackIndex;
89     return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr;
90   };
91   for (; End->Next; End = End->Next) {
92     if (End->Next->CanBreakBefore)
93       break;
94     if (!End->Next->closesScope())
95       continue;
96     if (End->Next->MatchingParen &&
97         End->Next->MatchingParen->isOneOf(
98             tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) {
99       const ParenState *State = FindParenState(End->Next->MatchingParen);
100       if (State && State->BreakBeforeClosingBrace)
101         break;
102     }
103   }
104   return End->TotalLength - Tok.TotalLength + 1;
105 }
106 
107 static unsigned getLengthToNextOperator(const FormatToken &Tok) {
108   if (!Tok.NextOperator)
109     return 0;
110   return Tok.NextOperator->TotalLength - Tok.TotalLength;
111 }
112 
113 // Returns \c true if \c Tok is the "." or "->" of a call and starts the next
114 // segment of a builder type call.
115 static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) {
116   return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope();
117 }
118 
119 // Returns \c true if \c Current starts a new parameter.
120 static bool startsNextParameter(const FormatToken &Current,
121                                 const FormatStyle &Style) {
122   const FormatToken &Previous = *Current.Previous;
123   if (Current.is(TT_CtorInitializerComma) &&
124       Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma)
125     return true;
126   if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName))
127     return true;
128   return Previous.is(tok::comma) && !Current.isTrailingComment() &&
129          ((Previous.isNot(TT_CtorInitializerComma) ||
130            Style.BreakConstructorInitializers !=
131                FormatStyle::BCIS_BeforeComma) &&
132           (Previous.isNot(TT_InheritanceComma) ||
133            Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma));
134 }
135 
136 static bool opensProtoMessageField(const FormatToken &LessTok,
137                                    const FormatStyle &Style) {
138   if (LessTok.isNot(tok::less))
139     return false;
140   return Style.Language == FormatStyle::LK_TextProto ||
141          (Style.Language == FormatStyle::LK_Proto &&
142           (LessTok.NestingLevel > 0 ||
143            (LessTok.Previous && LessTok.Previous->is(tok::equal))));
144 }
145 
146 // Returns the delimiter of a raw string literal, or None if TokenText is not
147 // the text of a raw string literal. The delimiter could be the empty string.
148 // For example, the delimiter of R"deli(cont)deli" is deli.
149 static llvm::Optional<StringRef> getRawStringDelimiter(StringRef TokenText) {
150   if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'.
151       || !TokenText.startswith("R\"") || !TokenText.endswith("\""))
152     return None;
153 
154   // A raw string starts with 'R"<delimiter>(' and delimiter is ascii and has
155   // size at most 16 by the standard, so the first '(' must be among the first
156   // 19 bytes.
157   size_t LParenPos = TokenText.substr(0, 19).find_first_of('(');
158   if (LParenPos == StringRef::npos)
159     return None;
160   StringRef Delimiter = TokenText.substr(2, LParenPos - 2);
161 
162   // Check that the string ends in ')Delimiter"'.
163   size_t RParenPos = TokenText.size() - Delimiter.size() - 2;
164   if (TokenText[RParenPos] != ')')
165     return None;
166   if (!TokenText.substr(RParenPos + 1).startswith(Delimiter))
167     return None;
168   return Delimiter;
169 }
170 
171 // Returns the canonical delimiter for \p Language, or the empty string if no
172 // canonical delimiter is specified.
173 static StringRef
174 getCanonicalRawStringDelimiter(const FormatStyle &Style,
175                                FormatStyle::LanguageKind Language) {
176   for (const auto &Format : Style.RawStringFormats) {
177     if (Format.Language == Language)
178       return StringRef(Format.CanonicalDelimiter);
179   }
180   return "";
181 }
182 
183 RawStringFormatStyleManager::RawStringFormatStyleManager(
184     const FormatStyle &CodeStyle) {
185   for (const auto &RawStringFormat : CodeStyle.RawStringFormats) {
186     llvm::Optional<FormatStyle> LanguageStyle =
187         CodeStyle.GetLanguageStyle(RawStringFormat.Language);
188     if (!LanguageStyle) {
189       FormatStyle PredefinedStyle;
190       if (!getPredefinedStyle(RawStringFormat.BasedOnStyle,
191                               RawStringFormat.Language, &PredefinedStyle)) {
192         PredefinedStyle = getLLVMStyle();
193         PredefinedStyle.Language = RawStringFormat.Language;
194       }
195       LanguageStyle = PredefinedStyle;
196     }
197     LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit;
198     for (StringRef Delimiter : RawStringFormat.Delimiters) {
199       DelimiterStyle.insert({Delimiter, *LanguageStyle});
200     }
201     for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions) {
202       EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle});
203     }
204   }
205 }
206 
207 llvm::Optional<FormatStyle>
208 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
209   auto It = DelimiterStyle.find(Delimiter);
210   if (It == DelimiterStyle.end())
211     return None;
212   return It->second;
213 }
214 
215 llvm::Optional<FormatStyle>
216 RawStringFormatStyleManager::getEnclosingFunctionStyle(
217     StringRef EnclosingFunction) const {
218   auto It = EnclosingFunctionStyle.find(EnclosingFunction);
219   if (It == EnclosingFunctionStyle.end())
220     return None;
221   return It->second;
222 }
223 
224 ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style,
225                                            const AdditionalKeywords &Keywords,
226                                            const SourceManager &SourceMgr,
227                                            WhitespaceManager &Whitespaces,
228                                            encoding::Encoding Encoding,
229                                            bool BinPackInconclusiveFunctions)
230     : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr),
231       Whitespaces(Whitespaces), Encoding(Encoding),
232       BinPackInconclusiveFunctions(BinPackInconclusiveFunctions),
233       CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {}
234 
235 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent,
236                                                 unsigned FirstStartColumn,
237                                                 const AnnotatedLine *Line,
238                                                 bool DryRun) {
239   LineState State;
240   State.FirstIndent = FirstIndent;
241   if (FirstStartColumn && Line->First->NewlinesBefore == 0)
242     State.Column = FirstStartColumn;
243   else
244     State.Column = FirstIndent;
245   // With preprocessor directive indentation, the line starts on column 0
246   // since it's indented after the hash, but FirstIndent is set to the
247   // preprocessor indent.
248   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
249       (Line->Type == LT_PreprocessorDirective ||
250        Line->Type == LT_ImportStatement))
251     State.Column = 0;
252   State.Line = Line;
253   State.NextToken = Line->First;
254   State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent,
255                                    /*AvoidBinPacking=*/false,
256                                    /*NoLineBreak=*/false));
257   State.LineContainsContinuedForLoopSection = false;
258   State.NoContinuation = false;
259   State.StartOfStringLiteral = 0;
260   State.StartOfLineLevel = 0;
261   State.LowestLevelOnLine = 0;
262   State.IgnoreStackForComparison = false;
263 
264   if (Style.Language == FormatStyle::LK_TextProto) {
265     // We need this in order to deal with the bin packing of text fields at
266     // global scope.
267     State.Stack.back().AvoidBinPacking = true;
268     State.Stack.back().BreakBeforeParameter = true;
269     State.Stack.back().AlignColons = false;
270   }
271 
272   // The first token has already been indented and thus consumed.
273   moveStateToNextToken(State, DryRun, /*Newline=*/false);
274   return State;
275 }
276 
277 bool ContinuationIndenter::canBreak(const LineState &State) {
278   const FormatToken &Current = *State.NextToken;
279   const FormatToken &Previous = *Current.Previous;
280   assert(&Previous == Current.Previous);
281   if (!Current.CanBreakBefore && !(State.Stack.back().BreakBeforeClosingBrace &&
282                                    Current.closesBlockOrBlockTypeList(Style)))
283     return false;
284   // The opening "{" of a braced list has to be on the same line as the first
285   // element if it is nested in another braced init list or function call.
286   if (!Current.MustBreakBefore && Previous.is(tok::l_brace) &&
287       Previous.isNot(TT_DictLiteral) && Previous.BlockKind == BK_BracedInit &&
288       Previous.Previous &&
289       Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma))
290     return false;
291   // This prevents breaks like:
292   //   ...
293   //   SomeParameter, OtherParameter).DoSomething(
294   //   ...
295   // As they hide "DoSomething" and are generally bad for readability.
296   if (Previous.opensScope() && Previous.isNot(tok::l_brace) &&
297       State.LowestLevelOnLine < State.StartOfLineLevel &&
298       State.LowestLevelOnLine < Current.NestingLevel)
299     return false;
300   if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder)
301     return false;
302 
303   // Don't create a 'hanging' indent if there are multiple blocks in a single
304   // statement.
305   if (Previous.is(tok::l_brace) && State.Stack.size() > 1 &&
306       State.Stack[State.Stack.size() - 2].NestedBlockInlined &&
307       State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks)
308     return false;
309 
310   // Don't break after very short return types (e.g. "void") as that is often
311   // unexpected.
312   if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) {
313     if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None)
314       return false;
315   }
316 
317   // If binary operators are moved to the next line (including commas for some
318   // styles of constructor initializers), that's always ok.
319   if (!Current.isOneOf(TT_BinaryOperator, tok::comma) &&
320       State.Stack.back().NoLineBreakInOperand)
321     return false;
322 
323   if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr))
324     return false;
325 
326   return !State.Stack.back().NoLineBreak;
327 }
328 
329 bool ContinuationIndenter::mustBreak(const LineState &State) {
330   const FormatToken &Current = *State.NextToken;
331   const FormatToken &Previous = *Current.Previous;
332   if (Current.MustBreakBefore || Current.is(TT_InlineASMColon))
333     return true;
334   if (State.Stack.back().BreakBeforeClosingBrace &&
335       Current.closesBlockOrBlockTypeList(Style))
336     return true;
337   if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection)
338     return true;
339   if (Style.Language == FormatStyle::LK_ObjC &&
340       Current.ObjCSelectorNameParts > 1 &&
341       Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) {
342     return true;
343   }
344   if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
345        (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
346         Style.isCpp() &&
347         // FIXME: This is a temporary workaround for the case where clang-format
348         // sets BreakBeforeParameter to avoid bin packing and this creates a
349         // completely unnecessary line break after a template type that isn't
350         // line-wrapped.
351         (Previous.NestingLevel == 1 || Style.BinPackParameters)) ||
352        (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
353         Previous.isNot(tok::question)) ||
354        (!Style.BreakBeforeTernaryOperators &&
355         Previous.is(TT_ConditionalExpr))) &&
356       State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() &&
357       !Current.isOneOf(tok::r_paren, tok::r_brace))
358     return true;
359   if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) ||
360        (Previous.is(TT_ArrayInitializerLSquare) &&
361         Previous.ParameterCount > 1) ||
362        opensProtoMessageField(Previous, Style)) &&
363       Style.ColumnLimit > 0 &&
364       getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 >
365           getColumnLimit(State))
366     return true;
367 
368   const FormatToken &BreakConstructorInitializersToken =
369       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon
370           ? Previous
371           : Current;
372   if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) &&
373       (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
374            getColumnLimit(State) ||
375        State.Stack.back().BreakBeforeParameter) &&
376       (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All ||
377        Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
378        Style.ColumnLimit != 0))
379     return true;
380 
381   if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) &&
382       State.Line->startsWith(TT_ObjCMethodSpecifier))
383     return true;
384   if (Current.is(TT_SelectorName) && !Previous.is(tok::at) &&
385       State.Stack.back().ObjCSelectorNameFound &&
386       State.Stack.back().BreakBeforeParameter)
387     return true;
388 
389   unsigned NewLineColumn = getNewLineColumn(State);
390   if (Current.isMemberAccess() && Style.ColumnLimit != 0 &&
391       State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit &&
392       (State.Column > NewLineColumn ||
393        Current.NestingLevel < State.StartOfLineLevel))
394     return true;
395 
396   if (startsSegmentOfBuilderTypeCall(Current) &&
397       (State.Stack.back().CallContinuation != 0 ||
398        State.Stack.back().BreakBeforeParameter) &&
399       // JavaScript is treated different here as there is a frequent pattern:
400       //   SomeFunction(function() {
401       //     ...
402       //   }.bind(...));
403       // FIXME: We should find a more generic solution to this problem.
404       !(State.Column <= NewLineColumn &&
405         Style.Language == FormatStyle::LK_JavaScript) &&
406       !(Previous.closesScopeAfterBlock() && State.Column <= NewLineColumn))
407     return true;
408 
409   // If the template declaration spans multiple lines, force wrap before the
410   // function/class declaration
411   if (Previous.ClosesTemplateDeclaration &&
412       State.Stack.back().BreakBeforeParameter && Current.CanBreakBefore)
413     return true;
414 
415   if (State.Column <= NewLineColumn)
416     return false;
417 
418   if (Style.AlwaysBreakBeforeMultilineStrings &&
419       (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth ||
420        Previous.is(tok::comma) || Current.NestingLevel < 2) &&
421       !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at) &&
422       !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
423       nextIsMultilineString(State))
424     return true;
425 
426   // Using CanBreakBefore here and below takes care of the decision whether the
427   // current style uses wrapping before or after operators for the given
428   // operator.
429   if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
430     // If we need to break somewhere inside the LHS of a binary expression, we
431     // should also break after the operator. Otherwise, the formatting would
432     // hide the operator precedence, e.g. in:
433     //   if (aaaaaaaaaaaaaa ==
434     //           bbbbbbbbbbbbbb && c) {..
435     // For comparisons, we only apply this rule, if the LHS is a binary
436     // expression itself as otherwise, the line breaks seem superfluous.
437     // We need special cases for ">>" which we have split into two ">" while
438     // lexing in order to make template parsing easier.
439     bool IsComparison = (Previous.getPrecedence() == prec::Relational ||
440                          Previous.getPrecedence() == prec::Equality ||
441                          Previous.getPrecedence() == prec::Spaceship) &&
442                         Previous.Previous &&
443                         Previous.Previous->isNot(TT_BinaryOperator); // For >>.
444     bool LHSIsBinaryExpr =
445         Previous.Previous && Previous.Previous->EndsBinaryExpression;
446     if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() &&
447         Previous.getPrecedence() != prec::Assignment &&
448         State.Stack.back().BreakBeforeParameter)
449       return true;
450   } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
451              State.Stack.back().BreakBeforeParameter) {
452     return true;
453   }
454 
455   // Same as above, but for the first "<<" operator.
456   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
457       State.Stack.back().BreakBeforeParameter &&
458       State.Stack.back().FirstLessLess == 0)
459     return true;
460 
461   if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
462     // Always break after "template <...>" and leading annotations. This is only
463     // for cases where the entire line does not fit on a single line as a
464     // different LineFormatter would be used otherwise.
465     if (Previous.ClosesTemplateDeclaration)
466       return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No;
467     if (Previous.is(TT_FunctionAnnotationRParen))
468       return true;
469     if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
470         Current.isNot(TT_LeadingJavaAnnotation))
471       return true;
472   }
473 
474   // If the return type spans multiple lines, wrap before the function name.
475   if ((Current.is(TT_FunctionDeclarationName) ||
476        (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) &&
477       !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter)
478     return true;
479 
480   // The following could be precomputed as they do not depend on the state.
481   // However, as they should take effect only if the UnwrappedLine does not fit
482   // into the ColumnLimit, they are checked here in the ContinuationIndenter.
483   if (Style.ColumnLimit != 0 && Previous.BlockKind == BK_Block &&
484       Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment))
485     return true;
486 
487   if (Current.is(tok::lessless) &&
488       ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
489        (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") ||
490                                      Previous.TokenText == "\'\\n\'"))))
491     return true;
492 
493   if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
494     return true;
495 
496   if (State.NoContinuation)
497     return true;
498 
499   return false;
500 }
501 
502 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
503                                                bool DryRun,
504                                                unsigned ExtraSpaces) {
505   const FormatToken &Current = *State.NextToken;
506 
507   assert(!State.Stack.empty());
508   State.NoContinuation = false;
509 
510   if ((Current.is(TT_ImplicitStringLiteral) &&
511        (Current.Previous->Tok.getIdentifierInfo() == nullptr ||
512         Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() ==
513             tok::pp_not_keyword))) {
514     unsigned EndColumn =
515         SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
516     if (Current.LastNewlineOffset != 0) {
517       // If there is a newline within this token, the final column will solely
518       // determined by the current end column.
519       State.Column = EndColumn;
520     } else {
521       unsigned StartColumn =
522           SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
523       assert(EndColumn >= StartColumn);
524       State.Column += EndColumn - StartColumn;
525     }
526     moveStateToNextToken(State, DryRun, /*Newline=*/false);
527     return 0;
528   }
529 
530   unsigned Penalty = 0;
531   if (Newline)
532     Penalty = addTokenOnNewLine(State, DryRun);
533   else
534     addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
535 
536   return moveStateToNextToken(State, DryRun, Newline) + Penalty;
537 }
538 
539 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
540                                                  unsigned ExtraSpaces) {
541   FormatToken &Current = *State.NextToken;
542   const FormatToken &Previous = *State.NextToken->Previous;
543   if (Current.is(tok::equal) &&
544       (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
545       State.Stack.back().VariablePos == 0) {
546     State.Stack.back().VariablePos = State.Column;
547     // Move over * and & if they are bound to the variable name.
548     const FormatToken *Tok = &Previous;
549     while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) {
550       State.Stack.back().VariablePos -= Tok->ColumnWidth;
551       if (Tok->SpacesRequiredBefore != 0)
552         break;
553       Tok = Tok->Previous;
554     }
555     if (Previous.PartOfMultiVariableDeclStmt)
556       State.Stack.back().LastSpace = State.Stack.back().VariablePos;
557   }
558 
559   unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
560 
561   // Indent preprocessor directives after the hash if required.
562   int PPColumnCorrection = 0;
563   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
564       Previous.is(tok::hash) && State.FirstIndent > 0 &&
565       (State.Line->Type == LT_PreprocessorDirective ||
566        State.Line->Type == LT_ImportStatement)) {
567     Spaces += State.FirstIndent;
568 
569     // For preprocessor indent with tabs, State.Column will be 1 because of the
570     // hash. This causes second-level indents onward to have an extra space
571     // after the tabs. We avoid this misalignment by subtracting 1 from the
572     // column value passed to replaceWhitespace().
573     if (Style.UseTab != FormatStyle::UT_Never)
574       PPColumnCorrection = -1;
575   }
576 
577   if (!DryRun)
578     Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
579                                   State.Column + Spaces + PPColumnCorrection);
580 
581   // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
582   // declaration unless there is multiple inheritance.
583   if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
584       Current.is(TT_InheritanceColon))
585     State.Stack.back().NoLineBreak = true;
586   if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
587       Previous.is(TT_InheritanceColon))
588     State.Stack.back().NoLineBreak = true;
589 
590   if (Current.is(TT_SelectorName) &&
591       !State.Stack.back().ObjCSelectorNameFound) {
592     unsigned MinIndent =
593         std::max(State.FirstIndent + Style.ContinuationIndentWidth,
594                  State.Stack.back().Indent);
595     unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
596     if (Current.LongestObjCSelectorName == 0)
597       State.Stack.back().AlignColons = false;
598     else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
599       State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName;
600     else
601       State.Stack.back().ColonPos = FirstColonPos;
602   }
603 
604   // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by
605   // disallowing any further line breaks if there is no line break after the
606   // opening parenthesis. Don't break if it doesn't conserve columns.
607   if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak &&
608       Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
609       State.Column > getNewLineColumn(State) &&
610       (!Previous.Previous || !Previous.Previous->isOneOf(
611                                  tok::kw_for, tok::kw_while, tok::kw_switch)) &&
612       // Don't do this for simple (no expressions) one-argument function calls
613       // as that feels like needlessly wasting whitespace, e.g.:
614       //
615       //   caaaaaaaaaaaall(
616       //       caaaaaaaaaaaall(
617       //           caaaaaaaaaaaall(
618       //               caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
619       Current.FakeLParens.size() > 0 &&
620       Current.FakeLParens.back() > prec::Unknown)
621     State.Stack.back().NoLineBreak = true;
622   if (Previous.is(TT_TemplateString) && Previous.opensScope())
623     State.Stack.back().NoLineBreak = true;
624 
625   if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
626       Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) &&
627       (Current.isNot(TT_LineComment) || Previous.BlockKind == BK_BracedInit))
628     State.Stack.back().Indent = State.Column + Spaces;
629   if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style))
630     State.Stack.back().NoLineBreak = true;
631   if (startsSegmentOfBuilderTypeCall(Current) &&
632       State.Column > getNewLineColumn(State))
633     State.Stack.back().ContainsUnwrappedBuilder = true;
634 
635   if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java)
636     State.Stack.back().NoLineBreak = true;
637   if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
638       (Previous.MatchingParen &&
639        (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10)))
640     // If there is a function call with long parameters, break before trailing
641     // calls. This prevents things like:
642     //   EXPECT_CALL(SomeLongParameter).Times(
643     //       2);
644     // We don't want to do this for short parameters as they can just be
645     // indexes.
646     State.Stack.back().NoLineBreak = true;
647 
648   // Don't allow the RHS of an operator to be split over multiple lines unless
649   // there is a line-break right after the operator.
650   // Exclude relational operators, as there, it is always more desirable to
651   // have the LHS 'left' of the RHS.
652   const FormatToken *P = Current.getPreviousNonComment();
653   if (!Current.is(tok::comment) && P &&
654       (P->isOneOf(TT_BinaryOperator, tok::comma) ||
655        (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
656       !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
657       P->getPrecedence() != prec::Assignment &&
658       P->getPrecedence() != prec::Relational &&
659       P->getPrecedence() != prec::Spaceship) {
660     bool BreakBeforeOperator =
661         P->MustBreakBefore || P->is(tok::lessless) ||
662         (P->is(TT_BinaryOperator) &&
663          Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
664         (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
665     // Don't do this if there are only two operands. In these cases, there is
666     // always a nice vertical separation between them and the extra line break
667     // does not help.
668     bool HasTwoOperands =
669         P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr);
670     if ((!BreakBeforeOperator && !(HasTwoOperands && Style.AlignOperands)) ||
671         (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator))
672       State.Stack.back().NoLineBreakInOperand = true;
673   }
674 
675   State.Column += Spaces;
676   if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
677       Previous.Previous &&
678       (Previous.Previous->isOneOf(tok::kw_if, tok::kw_for) ||
679        Previous.Previous->endsSequence(tok::kw_constexpr, tok::kw_if))) {
680     // Treat the condition inside an if as if it was a second function
681     // parameter, i.e. let nested calls have a continuation indent.
682     State.Stack.back().LastSpace = State.Column;
683     State.Stack.back().NestedBlockIndent = State.Column;
684   } else if (!Current.isOneOf(tok::comment, tok::caret) &&
685              ((Previous.is(tok::comma) &&
686                !Previous.is(TT_OverloadedOperator)) ||
687               (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
688     State.Stack.back().LastSpace = State.Column;
689   } else if (Previous.is(TT_CtorInitializerColon) &&
690              Style.BreakConstructorInitializers ==
691                  FormatStyle::BCIS_AfterColon) {
692     State.Stack.back().Indent = State.Column;
693     State.Stack.back().LastSpace = State.Column;
694   } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr,
695                                TT_CtorInitializerColon)) &&
696              ((Previous.getPrecedence() != prec::Assignment &&
697                (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
698                 Previous.NextOperator)) ||
699               Current.StartsBinaryExpression)) {
700     // Indent relative to the RHS of the expression unless this is a simple
701     // assignment without binary expression on the RHS. Also indent relative to
702     // unary operators and the colons of constructor initializers.
703     if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
704       State.Stack.back().LastSpace = State.Column;
705   } else if (Previous.is(TT_InheritanceColon)) {
706     State.Stack.back().Indent = State.Column;
707     State.Stack.back().LastSpace = State.Column;
708   } else if (Previous.opensScope()) {
709     // If a function has a trailing call, indent all parameters from the
710     // opening parenthesis. This avoids confusing indents like:
711     //   OuterFunction(InnerFunctionCall( // break
712     //       ParameterToInnerFunction))   // break
713     //       .SecondInnerFunctionCall();
714     bool HasTrailingCall = false;
715     if (Previous.MatchingParen) {
716       const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
717       HasTrailingCall = Next && Next->isMemberAccess();
718     }
719     if (HasTrailingCall && State.Stack.size() > 1 &&
720         State.Stack[State.Stack.size() - 2].CallContinuation == 0)
721       State.Stack.back().LastSpace = State.Column;
722   }
723 }
724 
725 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
726                                                  bool DryRun) {
727   FormatToken &Current = *State.NextToken;
728   const FormatToken &Previous = *State.NextToken->Previous;
729 
730   // Extra penalty that needs to be added because of the way certain line
731   // breaks are chosen.
732   unsigned Penalty = 0;
733 
734   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
735   const FormatToken *NextNonComment = Previous.getNextNonComment();
736   if (!NextNonComment)
737     NextNonComment = &Current;
738   // The first line break on any NestingLevel causes an extra penalty in order
739   // prefer similar line breaks.
740   if (!State.Stack.back().ContainsLineBreak)
741     Penalty += 15;
742   State.Stack.back().ContainsLineBreak = true;
743 
744   Penalty += State.NextToken->SplitPenalty;
745 
746   // Breaking before the first "<<" is generally not desirable if the LHS is
747   // short. Also always add the penalty if the LHS is split over multiple lines
748   // to avoid unnecessary line breaks that just work around this penalty.
749   if (NextNonComment->is(tok::lessless) &&
750       State.Stack.back().FirstLessLess == 0 &&
751       (State.Column <= Style.ColumnLimit / 3 ||
752        State.Stack.back().BreakBeforeParameter))
753     Penalty += Style.PenaltyBreakFirstLessLess;
754 
755   State.Column = getNewLineColumn(State);
756 
757   // Indent nested blocks relative to this column, unless in a very specific
758   // JavaScript special case where:
759   //
760   //   var loooooong_name =
761   //       function() {
762   //     // code
763   //   }
764   //
765   // is common and should be formatted like a free-standing function. The same
766   // goes for wrapping before the lambda return type arrow.
767   if (!Current.is(TT_LambdaArrow) &&
768       (Style.Language != FormatStyle::LK_JavaScript ||
769        Current.NestingLevel != 0 || !PreviousNonComment ||
770        !PreviousNonComment->is(tok::equal) ||
771        !Current.isOneOf(Keywords.kw_async, Keywords.kw_function)))
772     State.Stack.back().NestedBlockIndent = State.Column;
773 
774   if (NextNonComment->isMemberAccess()) {
775     if (State.Stack.back().CallContinuation == 0)
776       State.Stack.back().CallContinuation = State.Column;
777   } else if (NextNonComment->is(TT_SelectorName)) {
778     if (!State.Stack.back().ObjCSelectorNameFound) {
779       if (NextNonComment->LongestObjCSelectorName == 0) {
780         State.Stack.back().AlignColons = false;
781       } else {
782         State.Stack.back().ColonPos =
783             (shouldIndentWrappedSelectorName(Style, State.Line->Type)
784                  ? std::max(State.Stack.back().Indent,
785                             State.FirstIndent + Style.ContinuationIndentWidth)
786                  : State.Stack.back().Indent) +
787             std::max(NextNonComment->LongestObjCSelectorName,
788                      NextNonComment->ColumnWidth);
789       }
790     } else if (State.Stack.back().AlignColons &&
791                State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) {
792       State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth;
793     }
794   } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
795              PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
796     // FIXME: This is hacky, find a better way. The problem is that in an ObjC
797     // method expression, the block should be aligned to the line starting it,
798     // e.g.:
799     //   [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
800     //                        ^(int *i) {
801     //                            // ...
802     //                        }];
803     // Thus, we set LastSpace of the next higher NestingLevel, to which we move
804     // when we consume all of the "}"'s FakeRParens at the "{".
805     if (State.Stack.size() > 1)
806       State.Stack[State.Stack.size() - 2].LastSpace =
807           std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
808           Style.ContinuationIndentWidth;
809   }
810 
811   if ((PreviousNonComment &&
812        PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
813        !State.Stack.back().AvoidBinPacking) ||
814       Previous.is(TT_BinaryOperator))
815     State.Stack.back().BreakBeforeParameter = false;
816   if (PreviousNonComment &&
817       PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) &&
818       Current.NestingLevel == 0)
819     State.Stack.back().BreakBeforeParameter = false;
820   if (NextNonComment->is(tok::question) ||
821       (PreviousNonComment && PreviousNonComment->is(tok::question)))
822     State.Stack.back().BreakBeforeParameter = true;
823   if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
824     State.Stack.back().BreakBeforeParameter = false;
825 
826   if (!DryRun) {
827     unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
828     if (Current.is(tok::r_brace) && Current.MatchingParen &&
829         // Only strip trailing empty lines for l_braces that have children, i.e.
830         // for function expressions (lambdas, arrows, etc).
831         !Current.MatchingParen->Children.empty()) {
832       // lambdas and arrow functions are expressions, thus their r_brace is not
833       // on its own line, and thus not covered by UnwrappedLineFormatter's logic
834       // about removing empty lines on closing blocks. Special case them here.
835       MaxEmptyLinesToKeep = 1;
836     }
837     unsigned Newlines =
838         std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
839     bool ContinuePPDirective =
840         State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
841     Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
842                                   ContinuePPDirective);
843   }
844 
845   if (!Current.isTrailingComment())
846     State.Stack.back().LastSpace = State.Column;
847   if (Current.is(tok::lessless))
848     // If we are breaking before a "<<", we always want to indent relative to
849     // RHS. This is necessary only for "<<", as we special-case it and don't
850     // always indent relative to the RHS.
851     State.Stack.back().LastSpace += 3; // 3 -> width of "<< ".
852 
853   State.StartOfLineLevel = Current.NestingLevel;
854   State.LowestLevelOnLine = Current.NestingLevel;
855 
856   // Any break on this level means that the parent level has been broken
857   // and we need to avoid bin packing there.
858   bool NestedBlockSpecialCase =
859       !Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
860       State.Stack[State.Stack.size() - 2].NestedBlockInlined;
861   if (!NestedBlockSpecialCase)
862     for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
863       State.Stack[i].BreakBeforeParameter = true;
864 
865   if (PreviousNonComment &&
866       !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
867       (PreviousNonComment->isNot(TT_TemplateCloser) ||
868        Current.NestingLevel != 0) &&
869       !PreviousNonComment->isOneOf(
870           TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
871           TT_LeadingJavaAnnotation) &&
872       Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope())
873     State.Stack.back().BreakBeforeParameter = true;
874 
875   // If we break after { or the [ of an array initializer, we should also break
876   // before the corresponding } or ].
877   if (PreviousNonComment &&
878       (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
879        opensProtoMessageField(*PreviousNonComment, Style)))
880     State.Stack.back().BreakBeforeClosingBrace = true;
881 
882   if (State.Stack.back().AvoidBinPacking) {
883     // If we are breaking after '(', '{', '<', this is not bin packing
884     // unless AllowAllParametersOfDeclarationOnNextLine is false or this is a
885     // dict/object literal.
886     if (!Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
887         (!Style.AllowAllParametersOfDeclarationOnNextLine &&
888          State.Line->MustBeDeclaration) ||
889         Previous.is(TT_DictLiteral))
890       State.Stack.back().BreakBeforeParameter = true;
891   }
892 
893   return Penalty;
894 }
895 
896 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
897   if (!State.NextToken || !State.NextToken->Previous)
898     return 0;
899   FormatToken &Current = *State.NextToken;
900   const FormatToken &Previous = *Current.Previous;
901   // If we are continuing an expression, we want to use the continuation indent.
902   unsigned ContinuationIndent =
903       std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
904       Style.ContinuationIndentWidth;
905   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
906   const FormatToken *NextNonComment = Previous.getNextNonComment();
907   if (!NextNonComment)
908     NextNonComment = &Current;
909 
910   // Java specific bits.
911   if (Style.Language == FormatStyle::LK_Java &&
912       Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends))
913     return std::max(State.Stack.back().LastSpace,
914                     State.Stack.back().Indent + Style.ContinuationIndentWidth);
915 
916   if (NextNonComment->is(tok::l_brace) && NextNonComment->BlockKind == BK_Block)
917     return Current.NestingLevel == 0 ? State.FirstIndent
918                                      : State.Stack.back().Indent;
919   if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
920        (Current.is(tok::greater) &&
921         (Style.Language == FormatStyle::LK_Proto ||
922          Style.Language == FormatStyle::LK_TextProto))) &&
923       State.Stack.size() > 1) {
924     if (Current.closesBlockOrBlockTypeList(Style))
925       return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
926     if (Current.MatchingParen &&
927         Current.MatchingParen->BlockKind == BK_BracedInit)
928       return State.Stack[State.Stack.size() - 2].LastSpace;
929     return State.FirstIndent;
930   }
931   // Indent a closing parenthesis at the previous level if followed by a semi or
932   // opening brace. This allows indentations such as:
933   //     foo(
934   //       a,
935   //     );
936   //     function foo(
937   //       a,
938   //     ) {
939   //       code(); //
940   //     }
941   if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
942       (!Current.Next || Current.Next->isOneOf(tok::semi, tok::l_brace)))
943     return State.Stack[State.Stack.size() - 2].LastSpace;
944   if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
945     return State.Stack[State.Stack.size() - 2].LastSpace;
946   if (Current.is(tok::identifier) && Current.Next &&
947       (Current.Next->is(TT_DictLiteral) ||
948        ((Style.Language == FormatStyle::LK_Proto ||
949          Style.Language == FormatStyle::LK_TextProto) &&
950         Current.Next->isOneOf(tok::less, tok::l_brace))))
951     return State.Stack.back().Indent;
952   if (NextNonComment->is(TT_ObjCStringLiteral) &&
953       State.StartOfStringLiteral != 0)
954     return State.StartOfStringLiteral - 1;
955   if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
956     return State.StartOfStringLiteral;
957   if (NextNonComment->is(tok::lessless) &&
958       State.Stack.back().FirstLessLess != 0)
959     return State.Stack.back().FirstLessLess;
960   if (NextNonComment->isMemberAccess()) {
961     if (State.Stack.back().CallContinuation == 0)
962       return ContinuationIndent;
963     return State.Stack.back().CallContinuation;
964   }
965   if (State.Stack.back().QuestionColumn != 0 &&
966       ((NextNonComment->is(tok::colon) &&
967         NextNonComment->is(TT_ConditionalExpr)) ||
968        Previous.is(TT_ConditionalExpr)))
969     return State.Stack.back().QuestionColumn;
970   if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0)
971     return State.Stack.back().VariablePos;
972   if ((PreviousNonComment &&
973        (PreviousNonComment->ClosesTemplateDeclaration ||
974         PreviousNonComment->isOneOf(
975             TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
976             TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
977       (!Style.IndentWrappedFunctionNames &&
978        NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName)))
979     return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent);
980   if (NextNonComment->is(TT_SelectorName)) {
981     if (!State.Stack.back().ObjCSelectorNameFound) {
982       unsigned MinIndent = State.Stack.back().Indent;
983       if (shouldIndentWrappedSelectorName(Style, State.Line->Type))
984         MinIndent = std::max(MinIndent,
985                              State.FirstIndent + Style.ContinuationIndentWidth);
986       // If LongestObjCSelectorName is 0, we are indenting the first
987       // part of an ObjC selector (or a selector component which is
988       // not colon-aligned due to block formatting).
989       //
990       // Otherwise, we are indenting a subsequent part of an ObjC
991       // selector which should be colon-aligned to the longest
992       // component of the ObjC selector.
993       //
994       // In either case, we want to respect Style.IndentWrappedFunctionNames.
995       return MinIndent +
996              std::max(NextNonComment->LongestObjCSelectorName,
997                       NextNonComment->ColumnWidth) -
998              NextNonComment->ColumnWidth;
999     }
1000     if (!State.Stack.back().AlignColons)
1001       return State.Stack.back().Indent;
1002     if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth)
1003       return State.Stack.back().ColonPos - NextNonComment->ColumnWidth;
1004     return State.Stack.back().Indent;
1005   }
1006   if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1007     return State.Stack.back().ColonPos;
1008   if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1009     if (State.Stack.back().StartOfArraySubscripts != 0)
1010       return State.Stack.back().StartOfArraySubscripts;
1011     return ContinuationIndent;
1012   }
1013 
1014   // This ensure that we correctly format ObjC methods calls without inputs,
1015   // i.e. where the last element isn't selector like: [callee method];
1016   if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1017       NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr))
1018     return State.Stack.back().Indent;
1019 
1020   if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1021       Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon))
1022     return ContinuationIndent;
1023   if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1024       PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral))
1025     return ContinuationIndent;
1026   if (NextNonComment->is(TT_CtorInitializerComma))
1027     return State.Stack.back().Indent;
1028   if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1029       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon)
1030     return State.Stack.back().Indent;
1031   if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1032       Style.BreakInheritanceList == FormatStyle::BILS_AfterColon)
1033     return State.Stack.back().Indent;
1034   if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1035                               TT_InheritanceComma))
1036     return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1037   if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1038       !Current.isOneOf(tok::colon, tok::comment))
1039     return ContinuationIndent;
1040   if (Current.is(TT_ProtoExtensionLSquare))
1041     return State.Stack.back().Indent;
1042   if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment &&
1043       PreviousNonComment->isNot(tok::r_brace))
1044     // Ensure that we fall back to the continuation indent width instead of
1045     // just flushing continuations left.
1046     return State.Stack.back().Indent + Style.ContinuationIndentWidth;
1047   return State.Stack.back().Indent;
1048 }
1049 
1050 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1051                                                     bool DryRun, bool Newline) {
1052   assert(State.Stack.size());
1053   const FormatToken &Current = *State.NextToken;
1054 
1055   if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1056     State.Stack.back().NoLineBreakInOperand = false;
1057   if (Current.is(TT_InheritanceColon))
1058     State.Stack.back().AvoidBinPacking = true;
1059   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1060     if (State.Stack.back().FirstLessLess == 0)
1061       State.Stack.back().FirstLessLess = State.Column;
1062     else
1063       State.Stack.back().LastOperatorWrapped = Newline;
1064   }
1065   if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1066     State.Stack.back().LastOperatorWrapped = Newline;
1067   if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1068       !Current.Previous->is(TT_ConditionalExpr))
1069     State.Stack.back().LastOperatorWrapped = Newline;
1070   if (Current.is(TT_ArraySubscriptLSquare) &&
1071       State.Stack.back().StartOfArraySubscripts == 0)
1072     State.Stack.back().StartOfArraySubscripts = State.Column;
1073   if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1074     State.Stack.back().QuestionColumn = State.Column;
1075   if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1076     const FormatToken *Previous = Current.Previous;
1077     while (Previous && Previous->isTrailingComment())
1078       Previous = Previous->Previous;
1079     if (Previous && Previous->is(tok::question))
1080       State.Stack.back().QuestionColumn = State.Column;
1081   }
1082   if (!Current.opensScope() && !Current.closesScope() &&
1083       !Current.is(TT_PointerOrReference))
1084     State.LowestLevelOnLine =
1085         std::min(State.LowestLevelOnLine, Current.NestingLevel);
1086   if (Current.isMemberAccess())
1087     State.Stack.back().StartOfFunctionCall =
1088         !Current.NextOperator ? 0 : State.Column;
1089   if (Current.is(TT_SelectorName))
1090     State.Stack.back().ObjCSelectorNameFound = true;
1091   if (Current.is(TT_CtorInitializerColon) &&
1092       Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1093     // Indent 2 from the column, so:
1094     // SomeClass::SomeClass()
1095     //     : First(...), ...
1096     //       Next(...)
1097     //       ^ line up here.
1098     State.Stack.back().Indent =
1099         State.Column +
1100         (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma
1101              ? 0
1102              : 2);
1103     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1104     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1105       State.Stack.back().AvoidBinPacking = true;
1106     State.Stack.back().BreakBeforeParameter = false;
1107   }
1108   if (Current.is(TT_CtorInitializerColon) &&
1109       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1110     State.Stack.back().Indent =
1111         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1112     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1113     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1114       State.Stack.back().AvoidBinPacking = true;
1115   }
1116   if (Current.is(TT_InheritanceColon))
1117     State.Stack.back().Indent =
1118         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1119   if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1120     State.Stack.back().NestedBlockIndent =
1121         State.Column + Current.ColumnWidth + 1;
1122   if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
1123     State.Stack.back().LastSpace = State.Column;
1124 
1125   // Insert scopes created by fake parenthesis.
1126   const FormatToken *Previous = Current.getPreviousNonComment();
1127 
1128   // Add special behavior to support a format commonly used for JavaScript
1129   // closures:
1130   //   SomeFunction(function() {
1131   //     foo();
1132   //     bar();
1133   //   }, a, b, c);
1134   if (Current.isNot(tok::comment) && Previous &&
1135       Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1136       !Previous->is(TT_DictLiteral) && State.Stack.size() > 1 &&
1137       !State.Stack.back().HasMultipleNestedBlocks) {
1138     if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1139       for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
1140         State.Stack[i].NoLineBreak = true;
1141     State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1142   }
1143   if (Previous &&
1144       (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) ||
1145        Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) &&
1146       !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) {
1147     State.Stack.back().NestedBlockInlined =
1148         !Newline &&
1149         (Previous->isNot(tok::l_paren) || Previous->ParameterCount > 1);
1150   }
1151 
1152   moveStatePastFakeLParens(State, Newline);
1153   moveStatePastScopeCloser(State);
1154   bool AllowBreak = !State.Stack.back().NoLineBreak &&
1155                     !State.Stack.back().NoLineBreakInOperand;
1156   moveStatePastScopeOpener(State, Newline);
1157   moveStatePastFakeRParens(State);
1158 
1159   if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1160     State.StartOfStringLiteral = State.Column + 1;
1161   else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0)
1162     State.StartOfStringLiteral = State.Column;
1163   else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1164            !Current.isStringLiteral())
1165     State.StartOfStringLiteral = 0;
1166 
1167   State.Column += Current.ColumnWidth;
1168   State.NextToken = State.NextToken->Next;
1169 
1170   unsigned Penalty = handleEndOfLine(Current, State, DryRun, AllowBreak);
1171 
1172   if (Current.Role)
1173     Current.Role->formatFromToken(State, this, DryRun);
1174   // If the previous has a special role, let it consume tokens as appropriate.
1175   // It is necessary to start at the previous token for the only implemented
1176   // role (comma separated list). That way, the decision whether or not to break
1177   // after the "{" is already done and both options are tried and evaluated.
1178   // FIXME: This is ugly, find a better way.
1179   if (Previous && Previous->Role)
1180     Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1181 
1182   return Penalty;
1183 }
1184 
1185 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1186                                                     bool Newline) {
1187   const FormatToken &Current = *State.NextToken;
1188   const FormatToken *Previous = Current.getPreviousNonComment();
1189 
1190   // Don't add extra indentation for the first fake parenthesis after
1191   // 'return', assignments or opening <({[. The indentation for these cases
1192   // is special cased.
1193   bool SkipFirstExtraIndent =
1194       (Previous && (Previous->opensScope() ||
1195                     Previous->isOneOf(tok::semi, tok::kw_return) ||
1196                     (Previous->getPrecedence() == prec::Assignment &&
1197                      Style.AlignOperands) ||
1198                     Previous->is(TT_ObjCMethodExpr)));
1199   for (SmallVectorImpl<prec::Level>::const_reverse_iterator
1200            I = Current.FakeLParens.rbegin(),
1201            E = Current.FakeLParens.rend();
1202        I != E; ++I) {
1203     ParenState NewParenState = State.Stack.back();
1204     NewParenState.Tok = nullptr;
1205     NewParenState.ContainsLineBreak = false;
1206     NewParenState.LastOperatorWrapped = true;
1207     NewParenState.NoLineBreak =
1208         NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand;
1209 
1210     // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1211     if (*I > prec::Comma)
1212       NewParenState.AvoidBinPacking = false;
1213 
1214     // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1215     // a builder type call after 'return' or, if the alignment after opening
1216     // brackets is disabled.
1217     if (!Current.isTrailingComment() &&
1218         (Style.AlignOperands || *I < prec::Assignment) &&
1219         (!Previous || Previous->isNot(tok::kw_return) ||
1220          (Style.Language != FormatStyle::LK_Java && *I > 0)) &&
1221         (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1222          *I != prec::Comma || Current.NestingLevel == 0))
1223       NewParenState.Indent =
1224           std::max(std::max(State.Column, NewParenState.Indent),
1225                    State.Stack.back().LastSpace);
1226 
1227     // Do not indent relative to the fake parentheses inserted for "." or "->".
1228     // This is a special case to make the following to statements consistent:
1229     //   OuterFunction(InnerFunctionCall( // break
1230     //       ParameterToInnerFunction));
1231     //   OuterFunction(SomeObject.InnerFunctionCall( // break
1232     //       ParameterToInnerFunction));
1233     if (*I > prec::Unknown)
1234       NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1235     if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) &&
1236         Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign)
1237       NewParenState.StartOfFunctionCall = State.Column;
1238 
1239     // Always indent conditional expressions. Never indent expression where
1240     // the 'operator' is ',', ';' or an assignment (i.e. *I <=
1241     // prec::Assignment) as those have different indentation rules. Indent
1242     // other expression, unless the indentation needs to be skipped.
1243     if (*I == prec::Conditional ||
1244         (!SkipFirstExtraIndent && *I > prec::Assignment &&
1245          !Current.isTrailingComment()))
1246       NewParenState.Indent += Style.ContinuationIndentWidth;
1247     if ((Previous && !Previous->opensScope()) || *I != prec::Comma)
1248       NewParenState.BreakBeforeParameter = false;
1249     State.Stack.push_back(NewParenState);
1250     SkipFirstExtraIndent = false;
1251   }
1252 }
1253 
1254 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1255   for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1256     unsigned VariablePos = State.Stack.back().VariablePos;
1257     if (State.Stack.size() == 1) {
1258       // Do not pop the last element.
1259       break;
1260     }
1261     State.Stack.pop_back();
1262     State.Stack.back().VariablePos = VariablePos;
1263   }
1264 }
1265 
1266 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1267                                                     bool Newline) {
1268   const FormatToken &Current = *State.NextToken;
1269   if (!Current.opensScope())
1270     return;
1271 
1272   if (Current.MatchingParen && Current.BlockKind == BK_Block) {
1273     moveStateToNewBlock(State);
1274     return;
1275   }
1276 
1277   unsigned NewIndent;
1278   unsigned LastSpace = State.Stack.back().LastSpace;
1279   bool AvoidBinPacking;
1280   bool BreakBeforeParameter = false;
1281   unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall,
1282                                         State.Stack.back().NestedBlockIndent);
1283   if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1284       opensProtoMessageField(Current, Style)) {
1285     if (Current.opensBlockOrBlockTypeList(Style)) {
1286       NewIndent = Style.IndentWidth +
1287                   std::min(State.Column, State.Stack.back().NestedBlockIndent);
1288     } else {
1289       NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth;
1290     }
1291     const FormatToken *NextNoComment = Current.getNextNonComment();
1292     bool EndsInComma = Current.MatchingParen &&
1293                        Current.MatchingParen->Previous &&
1294                        Current.MatchingParen->Previous->is(tok::comma);
1295     AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1296                       Style.Language == FormatStyle::LK_Proto ||
1297                       Style.Language == FormatStyle::LK_TextProto ||
1298                       !Style.BinPackArguments ||
1299                       (NextNoComment &&
1300                        NextNoComment->isOneOf(TT_DesignatedInitializerPeriod,
1301                                               TT_DesignatedInitializerLSquare));
1302     BreakBeforeParameter = EndsInComma;
1303     if (Current.ParameterCount > 1)
1304       NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1305   } else {
1306     NewIndent = Style.ContinuationIndentWidth +
1307                 std::max(State.Stack.back().LastSpace,
1308                          State.Stack.back().StartOfFunctionCall);
1309 
1310     // Ensure that different different brackets force relative alignment, e.g.:
1311     // void SomeFunction(vector<  // break
1312     //                       int> v);
1313     // FIXME: We likely want to do this for more combinations of brackets.
1314     if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1315       NewIndent = std::max(NewIndent, State.Stack.back().Indent);
1316       LastSpace = std::max(LastSpace, State.Stack.back().Indent);
1317     }
1318 
1319     bool EndsInComma =
1320         Current.MatchingParen &&
1321         Current.MatchingParen->getPreviousNonComment() &&
1322         Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1323 
1324     // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1325     // for backwards compatibility.
1326     bool ObjCBinPackProtocolList =
1327         (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1328          Style.BinPackParameters) ||
1329         Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1330 
1331     bool BinPackDeclaration =
1332         (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1333         (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1334 
1335     AvoidBinPacking =
1336         (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) ||
1337         (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1338         (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1339         (Style.ExperimentalAutoDetectBinPacking &&
1340          (Current.PackingKind == PPK_OnePerLine ||
1341           (!BinPackInconclusiveFunctions &&
1342            Current.PackingKind == PPK_Inconclusive)));
1343 
1344     if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen) {
1345       if (Style.ColumnLimit) {
1346         // If this '[' opens an ObjC call, determine whether all parameters fit
1347         // into one line and put one per line if they don't.
1348         if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1349             getColumnLimit(State))
1350           BreakBeforeParameter = true;
1351       } else {
1352         // For ColumnLimit = 0, we have to figure out whether there is or has to
1353         // be a line break within this call.
1354         for (const FormatToken *Tok = &Current;
1355              Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1356           if (Tok->MustBreakBefore ||
1357               (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1358             BreakBeforeParameter = true;
1359             break;
1360           }
1361         }
1362       }
1363     }
1364 
1365     if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma)
1366       BreakBeforeParameter = true;
1367   }
1368   // Generally inherit NoLineBreak from the current scope to nested scope.
1369   // However, don't do this for non-empty nested blocks, dict literals and
1370   // array literals as these follow different indentation rules.
1371   bool NoLineBreak =
1372       Current.Children.empty() &&
1373       !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1374       (State.Stack.back().NoLineBreak ||
1375        State.Stack.back().NoLineBreakInOperand ||
1376        (Current.is(TT_TemplateOpener) &&
1377         State.Stack.back().ContainsUnwrappedBuilder));
1378   State.Stack.push_back(
1379       ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1380   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1381   State.Stack.back().BreakBeforeParameter = BreakBeforeParameter;
1382   State.Stack.back().HasMultipleNestedBlocks = Current.BlockParameterCount > 1;
1383   State.Stack.back().IsInsideObjCArrayLiteral =
1384       Current.is(TT_ArrayInitializerLSquare) && Current.Previous &&
1385       Current.Previous->is(tok::at);
1386 }
1387 
1388 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1389   const FormatToken &Current = *State.NextToken;
1390   if (!Current.closesScope())
1391     return;
1392 
1393   // If we encounter a closing ), ], } or >, we can remove a level from our
1394   // stacks.
1395   if (State.Stack.size() > 1 &&
1396       (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1397        (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1398        State.NextToken->is(TT_TemplateCloser) ||
1399        (Current.is(tok::greater) && Current.is(TT_DictLiteral))))
1400     State.Stack.pop_back();
1401 
1402   // Reevaluate whether ObjC message arguments fit into one line.
1403   // If a receiver spans multiple lines, e.g.:
1404   //   [[object block:^{
1405   //     return 42;
1406   //   }] a:42 b:42];
1407   // BreakBeforeParameter is calculated based on an incorrect assumption
1408   // (it is checked whether the whole expression fits into one line without
1409   // considering a line break inside a message receiver).
1410   // We check whether arguements fit after receiver scope closer (into the same
1411   // line).
1412   if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen &&
1413       Current.MatchingParen->Previous) {
1414     const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1415     if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1416         CurrentScopeOpener.MatchingParen) {
1417       int NecessarySpaceInLine =
1418           getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1419           CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1420       if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1421           Style.ColumnLimit)
1422         State.Stack.back().BreakBeforeParameter = false;
1423     }
1424   }
1425 
1426   if (Current.is(tok::r_square)) {
1427     // If this ends the array subscript expr, reset the corresponding value.
1428     const FormatToken *NextNonComment = Current.getNextNonComment();
1429     if (NextNonComment && NextNonComment->isNot(tok::l_square))
1430       State.Stack.back().StartOfArraySubscripts = 0;
1431   }
1432 }
1433 
1434 void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1435   unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1436   // ObjC block sometimes follow special indentation rules.
1437   unsigned NewIndent =
1438       NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1439                                ? Style.ObjCBlockIndentWidth
1440                                : Style.IndentWidth);
1441   State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1442                                    State.Stack.back().LastSpace,
1443                                    /*AvoidBinPacking=*/true,
1444                                    /*NoLineBreak=*/false));
1445   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1446   State.Stack.back().BreakBeforeParameter = true;
1447 }
1448 
1449 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1450                                      unsigned TabWidth,
1451                                      encoding::Encoding Encoding) {
1452   size_t LastNewlinePos = Text.find_last_of("\n");
1453   if (LastNewlinePos == StringRef::npos) {
1454     return StartColumn +
1455            encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
1456   } else {
1457     return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
1458                                          /*StartColumn=*/0, TabWidth, Encoding);
1459   }
1460 }
1461 
1462 unsigned ContinuationIndenter::reformatRawStringLiteral(
1463     const FormatToken &Current, LineState &State,
1464     const FormatStyle &RawStringStyle, bool DryRun) {
1465   unsigned StartColumn = State.Column - Current.ColumnWidth;
1466   StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
1467   StringRef NewDelimiter =
1468       getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
1469   if (NewDelimiter.empty() || OldDelimiter.empty())
1470     NewDelimiter = OldDelimiter;
1471   // The text of a raw string is between the leading 'R"delimiter(' and the
1472   // trailing 'delimiter)"'.
1473   unsigned OldPrefixSize = 3 + OldDelimiter.size();
1474   unsigned OldSuffixSize = 2 + OldDelimiter.size();
1475   // We create a virtual text environment which expects a null-terminated
1476   // string, so we cannot use StringRef.
1477   std::string RawText =
1478       Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize);
1479   if (NewDelimiter != OldDelimiter) {
1480     // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
1481     // raw string.
1482     std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
1483     if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
1484       NewDelimiter = OldDelimiter;
1485   }
1486 
1487   unsigned NewPrefixSize = 3 + NewDelimiter.size();
1488   unsigned NewSuffixSize = 2 + NewDelimiter.size();
1489 
1490   // The first start column is the column the raw text starts after formatting.
1491   unsigned FirstStartColumn = StartColumn + NewPrefixSize;
1492 
1493   // The next start column is the intended indentation a line break inside
1494   // the raw string at level 0. It is determined by the following rules:
1495   //   - if the content starts on newline, it is one level more than the current
1496   //     indent, and
1497   //   - if the content does not start on a newline, it is the first start
1498   //     column.
1499   // These rules have the advantage that the formatted content both does not
1500   // violate the rectangle rule and visually flows within the surrounding
1501   // source.
1502   bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
1503   // If this token is the last parameter (checked by looking if it's followed by
1504   // `)`, the base the indent off the line's nested block indent. Otherwise,
1505   // base the indent off the arguments indent, so we can achieve:
1506   // fffffffffff(1, 2, 3, R"pb(
1507   //     key1: 1  #
1508   //     key2: 2)pb");
1509   //
1510   // fffffffffff(1, 2, 3,
1511   //             R"pb(
1512   //               key1: 1  #
1513   //               key2: 2
1514   //             )pb",
1515   //             5);
1516   unsigned CurrentIndent = (Current.Next && Current.Next->is(tok::r_paren))
1517                                ? State.Stack.back().NestedBlockIndent
1518                                : State.Stack.back().Indent;
1519   unsigned NextStartColumn = ContentStartsOnNewline
1520                                  ? CurrentIndent + Style.IndentWidth
1521                                  : FirstStartColumn;
1522 
1523   // The last start column is the column the raw string suffix starts if it is
1524   // put on a newline.
1525   // The last start column is the intended indentation of the raw string postfix
1526   // if it is put on a newline. It is determined by the following rules:
1527   //   - if the raw string prefix starts on a newline, it is the column where
1528   //     that raw string prefix starts, and
1529   //   - if the raw string prefix does not start on a newline, it is the current
1530   //     indent.
1531   unsigned LastStartColumn =
1532       Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent;
1533 
1534   std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
1535       RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
1536       FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
1537       /*Status=*/nullptr);
1538 
1539   auto NewCode = applyAllReplacements(RawText, Fixes.first);
1540   tooling::Replacements NoFixes;
1541   if (!NewCode) {
1542     return addMultilineToken(Current, State);
1543   }
1544   if (!DryRun) {
1545     if (NewDelimiter != OldDelimiter) {
1546       // In 'R"delimiter(...', the delimiter starts 2 characters after the start
1547       // of the token.
1548       SourceLocation PrefixDelimiterStart =
1549           Current.Tok.getLocation().getLocWithOffset(2);
1550       auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
1551           SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1552       if (PrefixErr) {
1553         llvm::errs()
1554             << "Failed to update the prefix delimiter of a raw string: "
1555             << llvm::toString(std::move(PrefixErr)) << "\n";
1556       }
1557       // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
1558       // position length - 1 - |delimiter|.
1559       SourceLocation SuffixDelimiterStart =
1560           Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
1561                                                      1 - OldDelimiter.size());
1562       auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
1563           SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1564       if (SuffixErr) {
1565         llvm::errs()
1566             << "Failed to update the suffix delimiter of a raw string: "
1567             << llvm::toString(std::move(SuffixErr)) << "\n";
1568       }
1569     }
1570     SourceLocation OriginLoc =
1571         Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
1572     for (const tooling::Replacement &Fix : Fixes.first) {
1573       auto Err = Whitespaces.addReplacement(tooling::Replacement(
1574           SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
1575           Fix.getLength(), Fix.getReplacementText()));
1576       if (Err) {
1577         llvm::errs() << "Failed to reformat raw string: "
1578                      << llvm::toString(std::move(Err)) << "\n";
1579       }
1580     }
1581   }
1582   unsigned RawLastLineEndColumn = getLastLineEndColumn(
1583       *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
1584   State.Column = RawLastLineEndColumn + NewSuffixSize;
1585   // Since we're updating the column to after the raw string literal here, we
1586   // have to manually add the penalty for the prefix R"delim( over the column
1587   // limit.
1588   unsigned PrefixExcessCharacters =
1589       StartColumn + NewPrefixSize > Style.ColumnLimit
1590           ? StartColumn + NewPrefixSize - Style.ColumnLimit
1591           : 0;
1592   bool IsMultiline =
1593       ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos);
1594   if (IsMultiline) {
1595     // Break before further function parameters on all levels.
1596     for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1597       State.Stack[i].BreakBeforeParameter = true;
1598   }
1599   return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
1600 }
1601 
1602 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
1603                                                  LineState &State) {
1604   // Break before further function parameters on all levels.
1605   for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1606     State.Stack[i].BreakBeforeParameter = true;
1607 
1608   unsigned ColumnsUsed = State.Column;
1609   // We can only affect layout of the first and the last line, so the penalty
1610   // for all other lines is constant, and we ignore it.
1611   State.Column = Current.LastLineColumnWidth;
1612 
1613   if (ColumnsUsed > getColumnLimit(State))
1614     return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
1615   return 0;
1616 }
1617 
1618 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
1619                                                LineState &State, bool DryRun,
1620                                                bool AllowBreak) {
1621   unsigned Penalty = 0;
1622   // Compute the raw string style to use in case this is a raw string literal
1623   // that can be reformatted.
1624   auto RawStringStyle = getRawStringStyle(Current, State);
1625   if (RawStringStyle && !Current.Finalized) {
1626     Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun);
1627   } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
1628     // Don't break multi-line tokens other than block comments and raw string
1629     // literals. Instead, just update the state.
1630     Penalty = addMultilineToken(Current, State);
1631   } else if (State.Line->Type != LT_ImportStatement) {
1632     // We generally don't break import statements.
1633     LineState OriginalState = State;
1634 
1635     // Whether we force the reflowing algorithm to stay strictly within the
1636     // column limit.
1637     bool Strict = false;
1638     // Whether the first non-strict attempt at reflowing did intentionally
1639     // exceed the column limit.
1640     bool Exceeded = false;
1641     std::tie(Penalty, Exceeded) = breakProtrudingToken(
1642         Current, State, AllowBreak, /*DryRun=*/true, Strict);
1643     if (Exceeded) {
1644       // If non-strict reflowing exceeds the column limit, try whether strict
1645       // reflowing leads to an overall lower penalty.
1646       LineState StrictState = OriginalState;
1647       unsigned StrictPenalty =
1648           breakProtrudingToken(Current, StrictState, AllowBreak,
1649                                /*DryRun=*/true, /*Strict=*/true)
1650               .first;
1651       Strict = StrictPenalty <= Penalty;
1652       if (Strict) {
1653         Penalty = StrictPenalty;
1654         State = StrictState;
1655       }
1656     }
1657     if (!DryRun) {
1658       // If we're not in dry-run mode, apply the changes with the decision on
1659       // strictness made above.
1660       breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
1661                            Strict);
1662     }
1663   }
1664   if (State.Column > getColumnLimit(State)) {
1665     unsigned ExcessCharacters = State.Column - getColumnLimit(State);
1666     Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
1667   }
1668   return Penalty;
1669 }
1670 
1671 // Returns the enclosing function name of a token, or the empty string if not
1672 // found.
1673 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
1674   // Look for: 'function(' or 'function<templates>(' before Current.
1675   auto Tok = Current.getPreviousNonComment();
1676   if (!Tok || !Tok->is(tok::l_paren))
1677     return "";
1678   Tok = Tok->getPreviousNonComment();
1679   if (!Tok)
1680     return "";
1681   if (Tok->is(TT_TemplateCloser)) {
1682     Tok = Tok->MatchingParen;
1683     if (Tok)
1684       Tok = Tok->getPreviousNonComment();
1685   }
1686   if (!Tok || !Tok->is(tok::identifier))
1687     return "";
1688   return Tok->TokenText;
1689 }
1690 
1691 llvm::Optional<FormatStyle>
1692 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
1693                                         const LineState &State) {
1694   if (!Current.isStringLiteral())
1695     return None;
1696   auto Delimiter = getRawStringDelimiter(Current.TokenText);
1697   if (!Delimiter)
1698     return None;
1699   auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
1700   if (!RawStringStyle && Delimiter->empty())
1701     RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
1702         getEnclosingFunctionName(Current));
1703   if (!RawStringStyle)
1704     return None;
1705   RawStringStyle->ColumnLimit = getColumnLimit(State);
1706   return RawStringStyle;
1707 }
1708 
1709 std::unique_ptr<BreakableToken>
1710 ContinuationIndenter::createBreakableToken(const FormatToken &Current,
1711                                            LineState &State, bool AllowBreak) {
1712   unsigned StartColumn = State.Column - Current.ColumnWidth;
1713   if (Current.isStringLiteral()) {
1714     // FIXME: String literal breaking is currently disabled for Java and JS, as
1715     // it requires strings to be merged using "+" which we don't support.
1716     if (Style.Language == FormatStyle::LK_Java ||
1717         Style.Language == FormatStyle::LK_JavaScript ||
1718         !Style.BreakStringLiterals || !AllowBreak)
1719       return nullptr;
1720 
1721     // Don't break string literals inside preprocessor directives (except for
1722     // #define directives, as their contents are stored in separate lines and
1723     // are not affected by this check).
1724     // This way we avoid breaking code with line directives and unknown
1725     // preprocessor directives that contain long string literals.
1726     if (State.Line->Type == LT_PreprocessorDirective)
1727       return nullptr;
1728     // Exempts unterminated string literals from line breaking. The user will
1729     // likely want to terminate the string before any line breaking is done.
1730     if (Current.IsUnterminatedLiteral)
1731       return nullptr;
1732     // Don't break string literals inside Objective-C array literals (doing so
1733     // raises the warning -Wobjc-string-concatenation).
1734     if (State.Stack.back().IsInsideObjCArrayLiteral) {
1735       return nullptr;
1736     }
1737 
1738     StringRef Text = Current.TokenText;
1739     StringRef Prefix;
1740     StringRef Postfix;
1741     // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
1742     // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
1743     // reduce the overhead) for each FormatToken, which is a string, so that we
1744     // don't run multiple checks here on the hot path.
1745     if ((Text.endswith(Postfix = "\"") &&
1746          (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") ||
1747           Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") ||
1748           Text.startswith(Prefix = "u8\"") ||
1749           Text.startswith(Prefix = "L\""))) ||
1750         (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) {
1751       // We need this to address the case where there is an unbreakable tail
1752       // only if certain other formatting decisions have been taken. The
1753       // UnbreakableTailLength of Current is an overapproximation is that case
1754       // and we need to be correct here.
1755       unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
1756                                            ? 0
1757                                            : Current.UnbreakableTailLength;
1758       return llvm::make_unique<BreakableStringLiteral>(
1759           Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
1760           State.Line->InPPDirective, Encoding, Style);
1761     }
1762   } else if (Current.is(TT_BlockComment)) {
1763     if (!Style.ReflowComments ||
1764         // If a comment token switches formatting, like
1765         // /* clang-format on */, we don't want to break it further,
1766         // but we may still want to adjust its indentation.
1767         switchesFormatting(Current)) {
1768       return nullptr;
1769     }
1770     return llvm::make_unique<BreakableBlockComment>(
1771         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1772         State.Line->InPPDirective, Encoding, Style);
1773   } else if (Current.is(TT_LineComment) &&
1774              (Current.Previous == nullptr ||
1775               Current.Previous->isNot(TT_ImplicitStringLiteral))) {
1776     if (!Style.ReflowComments ||
1777         CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
1778         switchesFormatting(Current))
1779       return nullptr;
1780     return llvm::make_unique<BreakableLineCommentSection>(
1781         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1782         /*InPPDirective=*/false, Encoding, Style);
1783   }
1784   return nullptr;
1785 }
1786 
1787 std::pair<unsigned, bool>
1788 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
1789                                            LineState &State, bool AllowBreak,
1790                                            bool DryRun, bool Strict) {
1791   std::unique_ptr<const BreakableToken> Token =
1792       createBreakableToken(Current, State, AllowBreak);
1793   if (!Token)
1794     return {0, false};
1795   assert(Token->getLineCount() > 0);
1796   unsigned ColumnLimit = getColumnLimit(State);
1797   if (Current.is(TT_LineComment)) {
1798     // We don't insert backslashes when breaking line comments.
1799     ColumnLimit = Style.ColumnLimit;
1800   }
1801   if (Current.UnbreakableTailLength >= ColumnLimit)
1802     return {0, false};
1803   // ColumnWidth was already accounted into State.Column before calling
1804   // breakProtrudingToken.
1805   unsigned StartColumn = State.Column - Current.ColumnWidth;
1806   unsigned NewBreakPenalty = Current.isStringLiteral()
1807                                  ? Style.PenaltyBreakString
1808                                  : Style.PenaltyBreakComment;
1809   // Stores whether we intentionally decide to let a line exceed the column
1810   // limit.
1811   bool Exceeded = false;
1812   // Stores whether we introduce a break anywhere in the token.
1813   bool BreakInserted = Token->introducesBreakBeforeToken();
1814   // Store whether we inserted a new line break at the end of the previous
1815   // logical line.
1816   bool NewBreakBefore = false;
1817   // We use a conservative reflowing strategy. Reflow starts after a line is
1818   // broken or the corresponding whitespace compressed. Reflow ends as soon as a
1819   // line that doesn't get reflown with the previous line is reached.
1820   bool Reflow = false;
1821   // Keep track of where we are in the token:
1822   // Where we are in the content of the current logical line.
1823   unsigned TailOffset = 0;
1824   // The column number we're currently at.
1825   unsigned ContentStartColumn =
1826       Token->getContentStartColumn(0, /*Break=*/false);
1827   // The number of columns left in the current logical line after TailOffset.
1828   unsigned RemainingTokenColumns =
1829       Token->getRemainingLength(0, TailOffset, ContentStartColumn);
1830   // Adapt the start of the token, for example indent.
1831   if (!DryRun)
1832     Token->adaptStartOfLine(0, Whitespaces);
1833 
1834   unsigned ContentIndent = 0;
1835   unsigned Penalty = 0;
1836   LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
1837                           << StartColumn << ".\n");
1838   for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
1839        LineIndex != EndIndex; ++LineIndex) {
1840     LLVM_DEBUG(llvm::dbgs()
1841                << "  Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
1842     NewBreakBefore = false;
1843     // If we did reflow the previous line, we'll try reflowing again. Otherwise
1844     // we'll start reflowing if the current line is broken or whitespace is
1845     // compressed.
1846     bool TryReflow = Reflow;
1847     // Break the current token until we can fit the rest of the line.
1848     while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
1849       LLVM_DEBUG(llvm::dbgs() << "    Over limit, need: "
1850                               << (ContentStartColumn + RemainingTokenColumns)
1851                               << ", space: " << ColumnLimit
1852                               << ", reflown prefix: " << ContentStartColumn
1853                               << ", offset in line: " << TailOffset << "\n");
1854       // If the current token doesn't fit, find the latest possible split in the
1855       // current line so that breaking at it will be under the column limit.
1856       // FIXME: Use the earliest possible split while reflowing to correctly
1857       // compress whitespace within a line.
1858       BreakableToken::Split Split =
1859           Token->getSplit(LineIndex, TailOffset, ColumnLimit,
1860                           ContentStartColumn, CommentPragmasRegex);
1861       if (Split.first == StringRef::npos) {
1862         // No break opportunity - update the penalty and continue with the next
1863         // logical line.
1864         if (LineIndex < EndIndex - 1)
1865           // The last line's penalty is handled in addNextStateToQueue() or when
1866           // calling replaceWhitespaceAfterLastLine below.
1867           Penalty += Style.PenaltyExcessCharacter *
1868                      (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
1869         LLVM_DEBUG(llvm::dbgs() << "    No break opportunity.\n");
1870         break;
1871       }
1872       assert(Split.first != 0);
1873 
1874       if (Token->supportsReflow()) {
1875         // Check whether the next natural split point after the current one can
1876         // still fit the line, either because we can compress away whitespace,
1877         // or because the penalty the excess characters introduce is lower than
1878         // the break penalty.
1879         // We only do this for tokens that support reflowing, and thus allow us
1880         // to change the whitespace arbitrarily (e.g. comments).
1881         // Other tokens, like string literals, can be broken on arbitrary
1882         // positions.
1883 
1884         // First, compute the columns from TailOffset to the next possible split
1885         // position.
1886         // For example:
1887         // ColumnLimit:     |
1888         // // Some text   that    breaks
1889         //    ^ tail offset
1890         //             ^-- split
1891         //    ^-------- to split columns
1892         //                    ^--- next split
1893         //    ^--------------- to next split columns
1894         unsigned ToSplitColumns = Token->getRangeLength(
1895             LineIndex, TailOffset, Split.first, ContentStartColumn);
1896         LLVM_DEBUG(llvm::dbgs() << "    ToSplit: " << ToSplitColumns << "\n");
1897 
1898         BreakableToken::Split NextSplit = Token->getSplit(
1899             LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
1900             ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
1901         // Compute the columns necessary to fit the next non-breakable sequence
1902         // into the current line.
1903         unsigned ToNextSplitColumns = 0;
1904         if (NextSplit.first == StringRef::npos) {
1905           ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
1906                                                          ContentStartColumn);
1907         } else {
1908           ToNextSplitColumns = Token->getRangeLength(
1909               LineIndex, TailOffset,
1910               Split.first + Split.second + NextSplit.first, ContentStartColumn);
1911         }
1912         // Compress the whitespace between the break and the start of the next
1913         // unbreakable sequence.
1914         ToNextSplitColumns =
1915             Token->getLengthAfterCompression(ToNextSplitColumns, Split);
1916         LLVM_DEBUG(llvm::dbgs()
1917                    << "    ContentStartColumn: " << ContentStartColumn << "\n");
1918         LLVM_DEBUG(llvm::dbgs()
1919                    << "    ToNextSplit: " << ToNextSplitColumns << "\n");
1920         // If the whitespace compression makes us fit, continue on the current
1921         // line.
1922         bool ContinueOnLine =
1923             ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
1924         unsigned ExcessCharactersPenalty = 0;
1925         if (!ContinueOnLine && !Strict) {
1926           // Similarly, if the excess characters' penalty is lower than the
1927           // penalty of introducing a new break, continue on the current line.
1928           ExcessCharactersPenalty =
1929               (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
1930               Style.PenaltyExcessCharacter;
1931           LLVM_DEBUG(llvm::dbgs()
1932                      << "    Penalty excess: " << ExcessCharactersPenalty
1933                      << "\n            break : " << NewBreakPenalty << "\n");
1934           if (ExcessCharactersPenalty < NewBreakPenalty) {
1935             Exceeded = true;
1936             ContinueOnLine = true;
1937           }
1938         }
1939         if (ContinueOnLine) {
1940           LLVM_DEBUG(llvm::dbgs() << "    Continuing on line...\n");
1941           // The current line fits after compressing the whitespace - reflow
1942           // the next line into it if possible.
1943           TryReflow = true;
1944           if (!DryRun)
1945             Token->compressWhitespace(LineIndex, TailOffset, Split,
1946                                       Whitespaces);
1947           // When we continue on the same line, leave one space between content.
1948           ContentStartColumn += ToSplitColumns + 1;
1949           Penalty += ExcessCharactersPenalty;
1950           TailOffset += Split.first + Split.second;
1951           RemainingTokenColumns = Token->getRemainingLength(
1952               LineIndex, TailOffset, ContentStartColumn);
1953           continue;
1954         }
1955       }
1956       LLVM_DEBUG(llvm::dbgs() << "    Breaking...\n");
1957       // Update the ContentIndent only if the current line was not reflown with
1958       // the previous line, since in that case the previous line should still
1959       // determine the ContentIndent. Also never intent the last line.
1960       if (!Reflow)
1961         ContentIndent = Token->getContentIndent(LineIndex);
1962       LLVM_DEBUG(llvm::dbgs()
1963                  << "    ContentIndent: " << ContentIndent << "\n");
1964       ContentStartColumn = ContentIndent + Token->getContentStartColumn(
1965                                                LineIndex, /*Break=*/true);
1966 
1967       unsigned NewRemainingTokenColumns = Token->getRemainingLength(
1968           LineIndex, TailOffset + Split.first + Split.second,
1969           ContentStartColumn);
1970       if (NewRemainingTokenColumns == 0) {
1971         // No content to indent.
1972         ContentIndent = 0;
1973         ContentStartColumn =
1974             Token->getContentStartColumn(LineIndex, /*Break=*/true);
1975         NewRemainingTokenColumns = Token->getRemainingLength(
1976             LineIndex, TailOffset + Split.first + Split.second,
1977             ContentStartColumn);
1978       }
1979 
1980       // When breaking before a tab character, it may be moved by a few columns,
1981       // but will still be expanded to the next tab stop, so we don't save any
1982       // columns.
1983       if (NewRemainingTokenColumns == RemainingTokenColumns) {
1984         // FIXME: Do we need to adjust the penalty?
1985         break;
1986       }
1987       assert(NewRemainingTokenColumns < RemainingTokenColumns);
1988 
1989       LLVM_DEBUG(llvm::dbgs() << "    Breaking at: " << TailOffset + Split.first
1990                               << ", " << Split.second << "\n");
1991       if (!DryRun)
1992         Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
1993                            Whitespaces);
1994 
1995       Penalty += NewBreakPenalty;
1996       TailOffset += Split.first + Split.second;
1997       RemainingTokenColumns = NewRemainingTokenColumns;
1998       BreakInserted = true;
1999       NewBreakBefore = true;
2000     }
2001     // In case there's another line, prepare the state for the start of the next
2002     // line.
2003     if (LineIndex + 1 != EndIndex) {
2004       unsigned NextLineIndex = LineIndex + 1;
2005       if (NewBreakBefore)
2006         // After breaking a line, try to reflow the next line into the current
2007         // one once RemainingTokenColumns fits.
2008         TryReflow = true;
2009       if (TryReflow) {
2010         // We decided that we want to try reflowing the next line into the
2011         // current one.
2012         // We will now adjust the state as if the reflow is successful (in
2013         // preparation for the next line), and see whether that works. If we
2014         // decide that we cannot reflow, we will later reset the state to the
2015         // start of the next line.
2016         Reflow = false;
2017         // As we did not continue breaking the line, RemainingTokenColumns is
2018         // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2019         // the position at which we want to format the next line if we do
2020         // actually reflow.
2021         // When we reflow, we need to add a space between the end of the current
2022         // line and the next line's start column.
2023         ContentStartColumn += RemainingTokenColumns + 1;
2024         // Get the split that we need to reflow next logical line into the end
2025         // of the current one; the split will include any leading whitespace of
2026         // the next logical line.
2027         BreakableToken::Split SplitBeforeNext =
2028             Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2029         LLVM_DEBUG(llvm::dbgs()
2030                    << "    Size of reflown text: " << ContentStartColumn
2031                    << "\n    Potential reflow split: ");
2032         if (SplitBeforeNext.first != StringRef::npos) {
2033           LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2034                                   << SplitBeforeNext.second << "\n");
2035           TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2036           // If the rest of the next line fits into the current line below the
2037           // column limit, we can safely reflow.
2038           RemainingTokenColumns = Token->getRemainingLength(
2039               NextLineIndex, TailOffset, ContentStartColumn);
2040           Reflow = true;
2041           if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2042             LLVM_DEBUG(llvm::dbgs()
2043                        << "    Over limit after reflow, need: "
2044                        << (ContentStartColumn + RemainingTokenColumns)
2045                        << ", space: " << ColumnLimit
2046                        << ", reflown prefix: " << ContentStartColumn
2047                        << ", offset in line: " << TailOffset << "\n");
2048             // If the whole next line does not fit, try to find a point in
2049             // the next line at which we can break so that attaching the part
2050             // of the next line to that break point onto the current line is
2051             // below the column limit.
2052             BreakableToken::Split Split =
2053                 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2054                                 ContentStartColumn, CommentPragmasRegex);
2055             if (Split.first == StringRef::npos) {
2056               LLVM_DEBUG(llvm::dbgs() << "    Did not find later break\n");
2057               Reflow = false;
2058             } else {
2059               // Check whether the first split point gets us below the column
2060               // limit. Note that we will execute this split below as part of
2061               // the normal token breaking and reflow logic within the line.
2062               unsigned ToSplitColumns = Token->getRangeLength(
2063                   NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2064               if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2065                 LLVM_DEBUG(llvm::dbgs() << "    Next split protrudes, need: "
2066                                         << (ContentStartColumn + ToSplitColumns)
2067                                         << ", space: " << ColumnLimit);
2068                 unsigned ExcessCharactersPenalty =
2069                     (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2070                     Style.PenaltyExcessCharacter;
2071                 if (NewBreakPenalty < ExcessCharactersPenalty) {
2072                   Reflow = false;
2073                 }
2074               }
2075             }
2076           }
2077         } else {
2078           LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2079         }
2080       }
2081       if (!Reflow) {
2082         // If we didn't reflow into the next line, the only space to consider is
2083         // the next logical line. Reset our state to match the start of the next
2084         // line.
2085         TailOffset = 0;
2086         ContentStartColumn =
2087             Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2088         RemainingTokenColumns = Token->getRemainingLength(
2089             NextLineIndex, TailOffset, ContentStartColumn);
2090         // Adapt the start of the token, for example indent.
2091         if (!DryRun)
2092           Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2093       } else {
2094         // If we found a reflow split and have added a new break before the next
2095         // line, we are going to remove the line break at the start of the next
2096         // logical line. For example, here we'll add a new line break after
2097         // 'text', and subsequently delete the line break between 'that' and
2098         // 'reflows'.
2099         //   // some text that
2100         //   // reflows
2101         // ->
2102         //   // some text
2103         //   // that reflows
2104         // When adding the line break, we also added the penalty for it, so we
2105         // need to subtract that penalty again when we remove the line break due
2106         // to reflowing.
2107         if (NewBreakBefore) {
2108           assert(Penalty >= NewBreakPenalty);
2109           Penalty -= NewBreakPenalty;
2110         }
2111         if (!DryRun)
2112           Token->reflow(NextLineIndex, Whitespaces);
2113       }
2114     }
2115   }
2116 
2117   BreakableToken::Split SplitAfterLastLine =
2118       Token->getSplitAfterLastLine(TailOffset);
2119   if (SplitAfterLastLine.first != StringRef::npos) {
2120     LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2121 
2122     // We add the last line's penalty here, since that line is going to be split
2123     // now.
2124     Penalty += Style.PenaltyExcessCharacter *
2125                (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2126 
2127     if (!DryRun)
2128       Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2129                                             Whitespaces);
2130     ContentStartColumn =
2131         Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2132     RemainingTokenColumns = Token->getRemainingLength(
2133         Token->getLineCount() - 1,
2134         TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2135         ContentStartColumn);
2136   }
2137 
2138   State.Column = ContentStartColumn + RemainingTokenColumns -
2139                  Current.UnbreakableTailLength;
2140 
2141   if (BreakInserted) {
2142     // If we break the token inside a parameter list, we need to break before
2143     // the next parameter on all levels, so that the next parameter is clearly
2144     // visible. Line comments already introduce a break.
2145     if (Current.isNot(TT_LineComment)) {
2146       for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
2147         State.Stack[i].BreakBeforeParameter = true;
2148     }
2149 
2150     if (Current.is(TT_BlockComment))
2151       State.NoContinuation = true;
2152 
2153     State.Stack.back().LastSpace = StartColumn;
2154   }
2155 
2156   Token->updateNextToken(State);
2157 
2158   return {Penalty, Exceeded};
2159 }
2160 
2161 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2162   // In preprocessor directives reserve two chars for trailing " \"
2163   return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2164 }
2165 
2166 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2167   const FormatToken &Current = *State.NextToken;
2168   if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2169     return false;
2170   // We never consider raw string literals "multiline" for the purpose of
2171   // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2172   // (see TokenAnnotator::mustBreakBefore().
2173   if (Current.TokenText.startswith("R\""))
2174     return false;
2175   if (Current.IsMultiline)
2176     return true;
2177   if (Current.getNextNonComment() &&
2178       Current.getNextNonComment()->isStringLiteral())
2179     return true; // Implicit concatenation.
2180   if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2181       State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2182           Style.ColumnLimit)
2183     return true; // String will be split.
2184   return false;
2185 }
2186 
2187 } // namespace format
2188 } // namespace clang
2189