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                         Keywords.kw_dollar) &&
423       !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
424       nextIsMultilineString(State))
425     return true;
426 
427   // Using CanBreakBefore here and below takes care of the decision whether the
428   // current style uses wrapping before or after operators for the given
429   // operator.
430   if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
431     // If we need to break somewhere inside the LHS of a binary expression, we
432     // should also break after the operator. Otherwise, the formatting would
433     // hide the operator precedence, e.g. in:
434     //   if (aaaaaaaaaaaaaa ==
435     //           bbbbbbbbbbbbbb && c) {..
436     // For comparisons, we only apply this rule, if the LHS is a binary
437     // expression itself as otherwise, the line breaks seem superfluous.
438     // We need special cases for ">>" which we have split into two ">" while
439     // lexing in order to make template parsing easier.
440     bool IsComparison = (Previous.getPrecedence() == prec::Relational ||
441                          Previous.getPrecedence() == prec::Equality ||
442                          Previous.getPrecedence() == prec::Spaceship) &&
443                         Previous.Previous &&
444                         Previous.Previous->isNot(TT_BinaryOperator); // For >>.
445     bool LHSIsBinaryExpr =
446         Previous.Previous && Previous.Previous->EndsBinaryExpression;
447     if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() &&
448         Previous.getPrecedence() != prec::Assignment &&
449         State.Stack.back().BreakBeforeParameter)
450       return true;
451   } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
452              State.Stack.back().BreakBeforeParameter) {
453     return true;
454   }
455 
456   // Same as above, but for the first "<<" operator.
457   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
458       State.Stack.back().BreakBeforeParameter &&
459       State.Stack.back().FirstLessLess == 0)
460     return true;
461 
462   if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
463     // Always break after "template <...>" and leading annotations. This is only
464     // for cases where the entire line does not fit on a single line as a
465     // different LineFormatter would be used otherwise.
466     if (Previous.ClosesTemplateDeclaration)
467       return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No;
468     if (Previous.is(TT_FunctionAnnotationRParen))
469       return true;
470     if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
471         Current.isNot(TT_LeadingJavaAnnotation))
472       return true;
473   }
474 
475   // If the return type spans multiple lines, wrap before the function name.
476   if ((Current.is(TT_FunctionDeclarationName) ||
477        (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) &&
478       !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter)
479     return true;
480 
481   // The following could be precomputed as they do not depend on the state.
482   // However, as they should take effect only if the UnwrappedLine does not fit
483   // into the ColumnLimit, they are checked here in the ContinuationIndenter.
484   if (Style.ColumnLimit != 0 && Previous.BlockKind == BK_Block &&
485       Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment))
486     return true;
487 
488   if (Current.is(tok::lessless) &&
489       ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
490        (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") ||
491                                      Previous.TokenText == "\'\\n\'"))))
492     return true;
493 
494   if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
495     return true;
496 
497   if (State.NoContinuation)
498     return true;
499 
500   return false;
501 }
502 
503 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
504                                                bool DryRun,
505                                                unsigned ExtraSpaces) {
506   const FormatToken &Current = *State.NextToken;
507 
508   assert(!State.Stack.empty());
509   State.NoContinuation = false;
510 
511   if ((Current.is(TT_ImplicitStringLiteral) &&
512        (Current.Previous->Tok.getIdentifierInfo() == nullptr ||
513         Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() ==
514             tok::pp_not_keyword))) {
515     unsigned EndColumn =
516         SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
517     if (Current.LastNewlineOffset != 0) {
518       // If there is a newline within this token, the final column will solely
519       // determined by the current end column.
520       State.Column = EndColumn;
521     } else {
522       unsigned StartColumn =
523           SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
524       assert(EndColumn >= StartColumn);
525       State.Column += EndColumn - StartColumn;
526     }
527     moveStateToNextToken(State, DryRun, /*Newline=*/false);
528     return 0;
529   }
530 
531   unsigned Penalty = 0;
532   if (Newline)
533     Penalty = addTokenOnNewLine(State, DryRun);
534   else
535     addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
536 
537   return moveStateToNextToken(State, DryRun, Newline) + Penalty;
538 }
539 
540 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
541                                                  unsigned ExtraSpaces) {
542   FormatToken &Current = *State.NextToken;
543   const FormatToken &Previous = *State.NextToken->Previous;
544   if (Current.is(tok::equal) &&
545       (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
546       State.Stack.back().VariablePos == 0) {
547     State.Stack.back().VariablePos = State.Column;
548     // Move over * and & if they are bound to the variable name.
549     const FormatToken *Tok = &Previous;
550     while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) {
551       State.Stack.back().VariablePos -= Tok->ColumnWidth;
552       if (Tok->SpacesRequiredBefore != 0)
553         break;
554       Tok = Tok->Previous;
555     }
556     if (Previous.PartOfMultiVariableDeclStmt)
557       State.Stack.back().LastSpace = State.Stack.back().VariablePos;
558   }
559 
560   unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
561 
562   // Indent preprocessor directives after the hash if required.
563   int PPColumnCorrection = 0;
564   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
565       Previous.is(tok::hash) && State.FirstIndent > 0 &&
566       (State.Line->Type == LT_PreprocessorDirective ||
567        State.Line->Type == LT_ImportStatement)) {
568     Spaces += State.FirstIndent;
569 
570     // For preprocessor indent with tabs, State.Column will be 1 because of the
571     // hash. This causes second-level indents onward to have an extra space
572     // after the tabs. We avoid this misalignment by subtracting 1 from the
573     // column value passed to replaceWhitespace().
574     if (Style.UseTab != FormatStyle::UT_Never)
575       PPColumnCorrection = -1;
576   }
577 
578   if (!DryRun)
579     Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
580                                   State.Column + Spaces + PPColumnCorrection);
581 
582   // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
583   // declaration unless there is multiple inheritance.
584   if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
585       Current.is(TT_InheritanceColon))
586     State.Stack.back().NoLineBreak = true;
587   if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
588       Previous.is(TT_InheritanceColon))
589     State.Stack.back().NoLineBreak = true;
590 
591   if (Current.is(TT_SelectorName) &&
592       !State.Stack.back().ObjCSelectorNameFound) {
593     unsigned MinIndent =
594         std::max(State.FirstIndent + Style.ContinuationIndentWidth,
595                  State.Stack.back().Indent);
596     unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
597     if (Current.LongestObjCSelectorName == 0)
598       State.Stack.back().AlignColons = false;
599     else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
600       State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName;
601     else
602       State.Stack.back().ColonPos = FirstColonPos;
603   }
604 
605   // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by
606   // disallowing any further line breaks if there is no line break after the
607   // opening parenthesis. Don't break if it doesn't conserve columns.
608   if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak &&
609       (Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) ||
610        (Previous.is(tok::l_brace) && Previous.BlockKind != BK_Block &&
611         Style.Cpp11BracedListStyle)) &&
612       State.Column > getNewLineColumn(State) &&
613       (!Previous.Previous || !Previous.Previous->isOneOf(
614                                  tok::kw_for, tok::kw_while, tok::kw_switch)) &&
615       // Don't do this for simple (no expressions) one-argument function calls
616       // as that feels like needlessly wasting whitespace, e.g.:
617       //
618       //   caaaaaaaaaaaall(
619       //       caaaaaaaaaaaall(
620       //           caaaaaaaaaaaall(
621       //               caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
622       Current.FakeLParens.size() > 0 &&
623       Current.FakeLParens.back() > prec::Unknown)
624     State.Stack.back().NoLineBreak = true;
625   if (Previous.is(TT_TemplateString) && Previous.opensScope())
626     State.Stack.back().NoLineBreak = true;
627 
628   if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
629       Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) &&
630       (Current.isNot(TT_LineComment) || Previous.BlockKind == BK_BracedInit))
631     State.Stack.back().Indent = State.Column + Spaces;
632   if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style))
633     State.Stack.back().NoLineBreak = true;
634   if (startsSegmentOfBuilderTypeCall(Current) &&
635       State.Column > getNewLineColumn(State))
636     State.Stack.back().ContainsUnwrappedBuilder = true;
637 
638   if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java)
639     State.Stack.back().NoLineBreak = true;
640   if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
641       (Previous.MatchingParen &&
642        (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10)))
643     // If there is a function call with long parameters, break before trailing
644     // calls. This prevents things like:
645     //   EXPECT_CALL(SomeLongParameter).Times(
646     //       2);
647     // We don't want to do this for short parameters as they can just be
648     // indexes.
649     State.Stack.back().NoLineBreak = true;
650 
651   // Don't allow the RHS of an operator to be split over multiple lines unless
652   // there is a line-break right after the operator.
653   // Exclude relational operators, as there, it is always more desirable to
654   // have the LHS 'left' of the RHS.
655   const FormatToken *P = Current.getPreviousNonComment();
656   if (!Current.is(tok::comment) && P &&
657       (P->isOneOf(TT_BinaryOperator, tok::comma) ||
658        (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
659       !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
660       P->getPrecedence() != prec::Assignment &&
661       P->getPrecedence() != prec::Relational &&
662       P->getPrecedence() != prec::Spaceship) {
663     bool BreakBeforeOperator =
664         P->MustBreakBefore || P->is(tok::lessless) ||
665         (P->is(TT_BinaryOperator) &&
666          Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
667         (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
668     // Don't do this if there are only two operands. In these cases, there is
669     // always a nice vertical separation between them and the extra line break
670     // does not help.
671     bool HasTwoOperands =
672         P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr);
673     if ((!BreakBeforeOperator && !(HasTwoOperands && Style.AlignOperands)) ||
674         (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator))
675       State.Stack.back().NoLineBreakInOperand = true;
676   }
677 
678   State.Column += Spaces;
679   if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
680       Previous.Previous &&
681       (Previous.Previous->is(tok::kw_for) || Previous.Previous->isIf())) {
682     // Treat the condition inside an if as if it was a second function
683     // parameter, i.e. let nested calls have a continuation indent.
684     State.Stack.back().LastSpace = State.Column;
685     State.Stack.back().NestedBlockIndent = State.Column;
686   } else if (!Current.isOneOf(tok::comment, tok::caret) &&
687              ((Previous.is(tok::comma) &&
688                !Previous.is(TT_OverloadedOperator)) ||
689               (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
690     State.Stack.back().LastSpace = State.Column;
691   } else if (Previous.is(TT_CtorInitializerColon) &&
692              Style.BreakConstructorInitializers ==
693                  FormatStyle::BCIS_AfterColon) {
694     State.Stack.back().Indent = State.Column;
695     State.Stack.back().LastSpace = State.Column;
696   } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr,
697                                TT_CtorInitializerColon)) &&
698              ((Previous.getPrecedence() != prec::Assignment &&
699                (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
700                 Previous.NextOperator)) ||
701               Current.StartsBinaryExpression)) {
702     // Indent relative to the RHS of the expression unless this is a simple
703     // assignment without binary expression on the RHS. Also indent relative to
704     // unary operators and the colons of constructor initializers.
705     if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
706       State.Stack.back().LastSpace = State.Column;
707   } else if (Previous.is(TT_InheritanceColon)) {
708     State.Stack.back().Indent = State.Column;
709     State.Stack.back().LastSpace = State.Column;
710   } else if (Previous.opensScope()) {
711     // If a function has a trailing call, indent all parameters from the
712     // opening parenthesis. This avoids confusing indents like:
713     //   OuterFunction(InnerFunctionCall( // break
714     //       ParameterToInnerFunction))   // break
715     //       .SecondInnerFunctionCall();
716     bool HasTrailingCall = false;
717     if (Previous.MatchingParen) {
718       const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
719       HasTrailingCall = Next && Next->isMemberAccess();
720     }
721     if (HasTrailingCall && State.Stack.size() > 1 &&
722         State.Stack[State.Stack.size() - 2].CallContinuation == 0)
723       State.Stack.back().LastSpace = State.Column;
724   }
725 }
726 
727 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
728                                                  bool DryRun) {
729   FormatToken &Current = *State.NextToken;
730   const FormatToken &Previous = *State.NextToken->Previous;
731 
732   // Extra penalty that needs to be added because of the way certain line
733   // breaks are chosen.
734   unsigned Penalty = 0;
735 
736   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
737   const FormatToken *NextNonComment = Previous.getNextNonComment();
738   if (!NextNonComment)
739     NextNonComment = &Current;
740   // The first line break on any NestingLevel causes an extra penalty in order
741   // prefer similar line breaks.
742   if (!State.Stack.back().ContainsLineBreak)
743     Penalty += 15;
744   State.Stack.back().ContainsLineBreak = true;
745 
746   Penalty += State.NextToken->SplitPenalty;
747 
748   // Breaking before the first "<<" is generally not desirable if the LHS is
749   // short. Also always add the penalty if the LHS is split over multiple lines
750   // to avoid unnecessary line breaks that just work around this penalty.
751   if (NextNonComment->is(tok::lessless) &&
752       State.Stack.back().FirstLessLess == 0 &&
753       (State.Column <= Style.ColumnLimit / 3 ||
754        State.Stack.back().BreakBeforeParameter))
755     Penalty += Style.PenaltyBreakFirstLessLess;
756 
757   State.Column = getNewLineColumn(State);
758 
759   // Indent nested blocks relative to this column, unless in a very specific
760   // JavaScript special case where:
761   //
762   //   var loooooong_name =
763   //       function() {
764   //     // code
765   //   }
766   //
767   // is common and should be formatted like a free-standing function. The same
768   // goes for wrapping before the lambda return type arrow.
769   if (!Current.is(TT_LambdaArrow) &&
770       (Style.Language != FormatStyle::LK_JavaScript ||
771        Current.NestingLevel != 0 || !PreviousNonComment ||
772        !PreviousNonComment->is(tok::equal) ||
773        !Current.isOneOf(Keywords.kw_async, Keywords.kw_function)))
774     State.Stack.back().NestedBlockIndent = State.Column;
775 
776   if (NextNonComment->isMemberAccess()) {
777     if (State.Stack.back().CallContinuation == 0)
778       State.Stack.back().CallContinuation = State.Column;
779   } else if (NextNonComment->is(TT_SelectorName)) {
780     if (!State.Stack.back().ObjCSelectorNameFound) {
781       if (NextNonComment->LongestObjCSelectorName == 0) {
782         State.Stack.back().AlignColons = false;
783       } else {
784         State.Stack.back().ColonPos =
785             (shouldIndentWrappedSelectorName(Style, State.Line->Type)
786                  ? std::max(State.Stack.back().Indent,
787                             State.FirstIndent + Style.ContinuationIndentWidth)
788                  : State.Stack.back().Indent) +
789             std::max(NextNonComment->LongestObjCSelectorName,
790                      NextNonComment->ColumnWidth);
791       }
792     } else if (State.Stack.back().AlignColons &&
793                State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) {
794       State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth;
795     }
796   } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
797              PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
798     // FIXME: This is hacky, find a better way. The problem is that in an ObjC
799     // method expression, the block should be aligned to the line starting it,
800     // e.g.:
801     //   [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
802     //                        ^(int *i) {
803     //                            // ...
804     //                        }];
805     // Thus, we set LastSpace of the next higher NestingLevel, to which we move
806     // when we consume all of the "}"'s FakeRParens at the "{".
807     if (State.Stack.size() > 1)
808       State.Stack[State.Stack.size() - 2].LastSpace =
809           std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
810           Style.ContinuationIndentWidth;
811   }
812 
813   if ((PreviousNonComment &&
814        PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
815        !State.Stack.back().AvoidBinPacking) ||
816       Previous.is(TT_BinaryOperator))
817     State.Stack.back().BreakBeforeParameter = false;
818   if (PreviousNonComment &&
819       PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) &&
820       Current.NestingLevel == 0)
821     State.Stack.back().BreakBeforeParameter = false;
822   if (NextNonComment->is(tok::question) ||
823       (PreviousNonComment && PreviousNonComment->is(tok::question)))
824     State.Stack.back().BreakBeforeParameter = true;
825   if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
826     State.Stack.back().BreakBeforeParameter = false;
827 
828   if (!DryRun) {
829     unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
830     if (Current.is(tok::r_brace) && Current.MatchingParen &&
831         // Only strip trailing empty lines for l_braces that have children, i.e.
832         // for function expressions (lambdas, arrows, etc).
833         !Current.MatchingParen->Children.empty()) {
834       // lambdas and arrow functions are expressions, thus their r_brace is not
835       // on its own line, and thus not covered by UnwrappedLineFormatter's logic
836       // about removing empty lines on closing blocks. Special case them here.
837       MaxEmptyLinesToKeep = 1;
838     }
839     unsigned Newlines =
840         std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
841     bool ContinuePPDirective =
842         State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
843     Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
844                                   ContinuePPDirective);
845   }
846 
847   if (!Current.isTrailingComment())
848     State.Stack.back().LastSpace = State.Column;
849   if (Current.is(tok::lessless))
850     // If we are breaking before a "<<", we always want to indent relative to
851     // RHS. This is necessary only for "<<", as we special-case it and don't
852     // always indent relative to the RHS.
853     State.Stack.back().LastSpace += 3; // 3 -> width of "<< ".
854 
855   State.StartOfLineLevel = Current.NestingLevel;
856   State.LowestLevelOnLine = Current.NestingLevel;
857 
858   // Any break on this level means that the parent level has been broken
859   // and we need to avoid bin packing there.
860   bool NestedBlockSpecialCase =
861       !Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
862       State.Stack[State.Stack.size() - 2].NestedBlockInlined;
863   if (!NestedBlockSpecialCase)
864     for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
865       State.Stack[i].BreakBeforeParameter = true;
866 
867   if (PreviousNonComment &&
868       !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
869       (PreviousNonComment->isNot(TT_TemplateCloser) ||
870        Current.NestingLevel != 0) &&
871       !PreviousNonComment->isOneOf(
872           TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
873           TT_LeadingJavaAnnotation) &&
874       Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope())
875     State.Stack.back().BreakBeforeParameter = true;
876 
877   // If we break after { or the [ of an array initializer, we should also break
878   // before the corresponding } or ].
879   if (PreviousNonComment &&
880       (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
881        opensProtoMessageField(*PreviousNonComment, Style)))
882     State.Stack.back().BreakBeforeClosingBrace = true;
883 
884   if (State.Stack.back().AvoidBinPacking) {
885     // If we are breaking after '(', '{', '<', or this is the break after a ':'
886     // to start a member initializater list in a constructor, this should not
887     // be considered bin packing unless the relevant AllowAll option is false or
888     // this is a dict/object literal.
889     bool PreviousIsBreakingCtorInitializerColon =
890         Previous.is(TT_CtorInitializerColon) &&
891         Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
892     if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
893           PreviousIsBreakingCtorInitializerColon) ||
894         (!Style.AllowAllParametersOfDeclarationOnNextLine &&
895          State.Line->MustBeDeclaration) ||
896         (!Style.AllowAllArgumentsOnNextLine &&
897          !State.Line->MustBeDeclaration) ||
898         (!Style.AllowAllConstructorInitializersOnNextLine &&
899          PreviousIsBreakingCtorInitializerColon) ||
900         Previous.is(TT_DictLiteral))
901       State.Stack.back().BreakBeforeParameter = true;
902 
903     // If we are breaking after a ':' to start a member initializer list,
904     // and we allow all arguments on the next line, we should not break
905     // before the next parameter.
906     if (PreviousIsBreakingCtorInitializerColon &&
907         Style.AllowAllConstructorInitializersOnNextLine)
908       State.Stack.back().BreakBeforeParameter = false;
909   }
910 
911   return Penalty;
912 }
913 
914 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
915   if (!State.NextToken || !State.NextToken->Previous)
916     return 0;
917   FormatToken &Current = *State.NextToken;
918   const FormatToken &Previous = *Current.Previous;
919   // If we are continuing an expression, we want to use the continuation indent.
920   unsigned ContinuationIndent =
921       std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) +
922       Style.ContinuationIndentWidth;
923   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
924   const FormatToken *NextNonComment = Previous.getNextNonComment();
925   if (!NextNonComment)
926     NextNonComment = &Current;
927 
928   // Java specific bits.
929   if (Style.Language == FormatStyle::LK_Java &&
930       Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends))
931     return std::max(State.Stack.back().LastSpace,
932                     State.Stack.back().Indent + Style.ContinuationIndentWidth);
933 
934   if (NextNonComment->is(tok::l_brace) && NextNonComment->BlockKind == BK_Block)
935     return Current.NestingLevel == 0 ? State.FirstIndent
936                                      : State.Stack.back().Indent;
937   if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
938        (Current.is(tok::greater) &&
939         (Style.Language == FormatStyle::LK_Proto ||
940          Style.Language == FormatStyle::LK_TextProto))) &&
941       State.Stack.size() > 1) {
942     if (Current.closesBlockOrBlockTypeList(Style))
943       return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
944     if (Current.MatchingParen &&
945         Current.MatchingParen->BlockKind == BK_BracedInit)
946       return State.Stack[State.Stack.size() - 2].LastSpace;
947     return State.FirstIndent;
948   }
949   // Indent a closing parenthesis at the previous level if followed by a semi,
950   // const, or opening brace. This allows indentations such as:
951   //     foo(
952   //       a,
953   //     );
954   //     int Foo::getter(
955   //         //
956   //     ) const {
957   //       return foo;
958   //     }
959   //     function foo(
960   //       a,
961   //     ) {
962   //       code(); //
963   //     }
964   if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
965       (!Current.Next ||
966        Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace)))
967     return State.Stack[State.Stack.size() - 2].LastSpace;
968   if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
969     return State.Stack[State.Stack.size() - 2].LastSpace;
970   if (Current.is(tok::identifier) && Current.Next &&
971       (Current.Next->is(TT_DictLiteral) ||
972        ((Style.Language == FormatStyle::LK_Proto ||
973          Style.Language == FormatStyle::LK_TextProto) &&
974         Current.Next->isOneOf(tok::less, tok::l_brace))))
975     return State.Stack.back().Indent;
976   if (NextNonComment->is(TT_ObjCStringLiteral) &&
977       State.StartOfStringLiteral != 0)
978     return State.StartOfStringLiteral - 1;
979   if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
980     return State.StartOfStringLiteral;
981   if (NextNonComment->is(tok::lessless) &&
982       State.Stack.back().FirstLessLess != 0)
983     return State.Stack.back().FirstLessLess;
984   if (NextNonComment->isMemberAccess()) {
985     if (State.Stack.back().CallContinuation == 0)
986       return ContinuationIndent;
987     return State.Stack.back().CallContinuation;
988   }
989   if (State.Stack.back().QuestionColumn != 0 &&
990       ((NextNonComment->is(tok::colon) &&
991         NextNonComment->is(TT_ConditionalExpr)) ||
992        Previous.is(TT_ConditionalExpr)))
993     return State.Stack.back().QuestionColumn;
994   if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0)
995     return State.Stack.back().VariablePos;
996   if ((PreviousNonComment &&
997        (PreviousNonComment->ClosesTemplateDeclaration ||
998         PreviousNonComment->isOneOf(
999             TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
1000             TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
1001       (!Style.IndentWrappedFunctionNames &&
1002        NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName)))
1003     return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent);
1004   if (NextNonComment->is(TT_SelectorName)) {
1005     if (!State.Stack.back().ObjCSelectorNameFound) {
1006       unsigned MinIndent = State.Stack.back().Indent;
1007       if (shouldIndentWrappedSelectorName(Style, State.Line->Type))
1008         MinIndent = std::max(MinIndent,
1009                              State.FirstIndent + Style.ContinuationIndentWidth);
1010       // If LongestObjCSelectorName is 0, we are indenting the first
1011       // part of an ObjC selector (or a selector component which is
1012       // not colon-aligned due to block formatting).
1013       //
1014       // Otherwise, we are indenting a subsequent part of an ObjC
1015       // selector which should be colon-aligned to the longest
1016       // component of the ObjC selector.
1017       //
1018       // In either case, we want to respect Style.IndentWrappedFunctionNames.
1019       return MinIndent +
1020              std::max(NextNonComment->LongestObjCSelectorName,
1021                       NextNonComment->ColumnWidth) -
1022              NextNonComment->ColumnWidth;
1023     }
1024     if (!State.Stack.back().AlignColons)
1025       return State.Stack.back().Indent;
1026     if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth)
1027       return State.Stack.back().ColonPos - NextNonComment->ColumnWidth;
1028     return State.Stack.back().Indent;
1029   }
1030   if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1031     return State.Stack.back().ColonPos;
1032   if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1033     if (State.Stack.back().StartOfArraySubscripts != 0)
1034       return State.Stack.back().StartOfArraySubscripts;
1035     return ContinuationIndent;
1036   }
1037 
1038   // This ensure that we correctly format ObjC methods calls without inputs,
1039   // i.e. where the last element isn't selector like: [callee method];
1040   if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1041       NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr))
1042     return State.Stack.back().Indent;
1043 
1044   if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1045       Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon))
1046     return ContinuationIndent;
1047   if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1048       PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral))
1049     return ContinuationIndent;
1050   if (NextNonComment->is(TT_CtorInitializerComma))
1051     return State.Stack.back().Indent;
1052   if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1053       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon)
1054     return State.Stack.back().Indent;
1055   if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1056       Style.BreakInheritanceList == FormatStyle::BILS_AfterColon)
1057     return State.Stack.back().Indent;
1058   if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1059                               TT_InheritanceComma))
1060     return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1061   if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1062       !Current.isOneOf(tok::colon, tok::comment))
1063     return ContinuationIndent;
1064   if (Current.is(TT_ProtoExtensionLSquare))
1065     return State.Stack.back().Indent;
1066   if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment &&
1067       !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma))
1068     // Ensure that we fall back to the continuation indent width instead of
1069     // just flushing continuations left.
1070     return State.Stack.back().Indent + Style.ContinuationIndentWidth;
1071   return State.Stack.back().Indent;
1072 }
1073 
1074 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1075                                                     bool DryRun, bool Newline) {
1076   assert(State.Stack.size());
1077   const FormatToken &Current = *State.NextToken;
1078 
1079   if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1080     State.Stack.back().NoLineBreakInOperand = false;
1081   if (Current.is(TT_InheritanceColon))
1082     State.Stack.back().AvoidBinPacking = true;
1083   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1084     if (State.Stack.back().FirstLessLess == 0)
1085       State.Stack.back().FirstLessLess = State.Column;
1086     else
1087       State.Stack.back().LastOperatorWrapped = Newline;
1088   }
1089   if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1090     State.Stack.back().LastOperatorWrapped = Newline;
1091   if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1092       !Current.Previous->is(TT_ConditionalExpr))
1093     State.Stack.back().LastOperatorWrapped = Newline;
1094   if (Current.is(TT_ArraySubscriptLSquare) &&
1095       State.Stack.back().StartOfArraySubscripts == 0)
1096     State.Stack.back().StartOfArraySubscripts = State.Column;
1097   if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1098     State.Stack.back().QuestionColumn = State.Column;
1099   if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1100     const FormatToken *Previous = Current.Previous;
1101     while (Previous && Previous->isTrailingComment())
1102       Previous = Previous->Previous;
1103     if (Previous && Previous->is(tok::question))
1104       State.Stack.back().QuestionColumn = State.Column;
1105   }
1106   if (!Current.opensScope() && !Current.closesScope() &&
1107       !Current.is(TT_PointerOrReference))
1108     State.LowestLevelOnLine =
1109         std::min(State.LowestLevelOnLine, Current.NestingLevel);
1110   if (Current.isMemberAccess())
1111     State.Stack.back().StartOfFunctionCall =
1112         !Current.NextOperator ? 0 : State.Column;
1113   if (Current.is(TT_SelectorName))
1114     State.Stack.back().ObjCSelectorNameFound = true;
1115   if (Current.is(TT_CtorInitializerColon) &&
1116       Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1117     // Indent 2 from the column, so:
1118     // SomeClass::SomeClass()
1119     //     : First(...), ...
1120     //       Next(...)
1121     //       ^ line up here.
1122     State.Stack.back().Indent =
1123         State.Column +
1124         (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma
1125              ? 0
1126              : 2);
1127     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1128     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) {
1129       State.Stack.back().AvoidBinPacking = true;
1130       State.Stack.back().BreakBeforeParameter =
1131           !Style.AllowAllConstructorInitializersOnNextLine;
1132     } else {
1133       State.Stack.back().BreakBeforeParameter = false;
1134     }
1135   }
1136   if (Current.is(TT_CtorInitializerColon) &&
1137       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1138     State.Stack.back().Indent =
1139         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1140     State.Stack.back().NestedBlockIndent = State.Stack.back().Indent;
1141     if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
1142       State.Stack.back().AvoidBinPacking = true;
1143   }
1144   if (Current.is(TT_InheritanceColon))
1145     State.Stack.back().Indent =
1146         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1147   if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1148     State.Stack.back().NestedBlockIndent =
1149         State.Column + Current.ColumnWidth + 1;
1150   if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
1151     State.Stack.back().LastSpace = State.Column;
1152 
1153   // Insert scopes created by fake parenthesis.
1154   const FormatToken *Previous = Current.getPreviousNonComment();
1155 
1156   // Add special behavior to support a format commonly used for JavaScript
1157   // closures:
1158   //   SomeFunction(function() {
1159   //     foo();
1160   //     bar();
1161   //   }, a, b, c);
1162   if (Current.isNot(tok::comment) && Previous &&
1163       Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1164       !Previous->is(TT_DictLiteral) && State.Stack.size() > 1 &&
1165       !State.Stack.back().HasMultipleNestedBlocks) {
1166     if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1167       for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i)
1168         State.Stack[i].NoLineBreak = true;
1169     State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1170   }
1171   if (Previous &&
1172       (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) ||
1173        Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) &&
1174       !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) {
1175     State.Stack.back().NestedBlockInlined =
1176         !Newline &&
1177         (Previous->isNot(tok::l_paren) || Previous->ParameterCount > 1);
1178   }
1179 
1180   moveStatePastFakeLParens(State, Newline);
1181   moveStatePastScopeCloser(State);
1182   bool AllowBreak = !State.Stack.back().NoLineBreak &&
1183                     !State.Stack.back().NoLineBreakInOperand;
1184   moveStatePastScopeOpener(State, Newline);
1185   moveStatePastFakeRParens(State);
1186 
1187   if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1188     State.StartOfStringLiteral = State.Column + 1;
1189   if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0)
1190     State.StartOfStringLiteral = State.Column + 1;
1191   else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0)
1192     State.StartOfStringLiteral = State.Column;
1193   else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1194            !Current.isStringLiteral())
1195     State.StartOfStringLiteral = 0;
1196 
1197   State.Column += Current.ColumnWidth;
1198   State.NextToken = State.NextToken->Next;
1199 
1200   unsigned Penalty =
1201       handleEndOfLine(Current, State, DryRun, AllowBreak, Newline);
1202 
1203   if (Current.Role)
1204     Current.Role->formatFromToken(State, this, DryRun);
1205   // If the previous has a special role, let it consume tokens as appropriate.
1206   // It is necessary to start at the previous token for the only implemented
1207   // role (comma separated list). That way, the decision whether or not to break
1208   // after the "{" is already done and both options are tried and evaluated.
1209   // FIXME: This is ugly, find a better way.
1210   if (Previous && Previous->Role)
1211     Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1212 
1213   return Penalty;
1214 }
1215 
1216 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1217                                                     bool Newline) {
1218   const FormatToken &Current = *State.NextToken;
1219   const FormatToken *Previous = Current.getPreviousNonComment();
1220 
1221   // Don't add extra indentation for the first fake parenthesis after
1222   // 'return', assignments or opening <({[. The indentation for these cases
1223   // is special cased.
1224   bool SkipFirstExtraIndent =
1225       (Previous && (Previous->opensScope() ||
1226                     Previous->isOneOf(tok::semi, tok::kw_return) ||
1227                     (Previous->getPrecedence() == prec::Assignment &&
1228                      Style.AlignOperands) ||
1229                     Previous->is(TT_ObjCMethodExpr)));
1230   for (SmallVectorImpl<prec::Level>::const_reverse_iterator
1231            I = Current.FakeLParens.rbegin(),
1232            E = Current.FakeLParens.rend();
1233        I != E; ++I) {
1234     ParenState NewParenState = State.Stack.back();
1235     NewParenState.Tok = nullptr;
1236     NewParenState.ContainsLineBreak = false;
1237     NewParenState.LastOperatorWrapped = true;
1238     NewParenState.NoLineBreak =
1239         NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand;
1240 
1241     // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1242     if (*I > prec::Comma)
1243       NewParenState.AvoidBinPacking = false;
1244 
1245     // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1246     // a builder type call after 'return' or, if the alignment after opening
1247     // brackets is disabled.
1248     if (!Current.isTrailingComment() &&
1249         (Style.AlignOperands || *I < prec::Assignment) &&
1250         (!Previous || Previous->isNot(tok::kw_return) ||
1251          (Style.Language != FormatStyle::LK_Java && *I > 0)) &&
1252         (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1253          *I != prec::Comma || Current.NestingLevel == 0))
1254       NewParenState.Indent =
1255           std::max(std::max(State.Column, NewParenState.Indent),
1256                    State.Stack.back().LastSpace);
1257 
1258     // Do not indent relative to the fake parentheses inserted for "." or "->".
1259     // This is a special case to make the following to statements consistent:
1260     //   OuterFunction(InnerFunctionCall( // break
1261     //       ParameterToInnerFunction));
1262     //   OuterFunction(SomeObject.InnerFunctionCall( // break
1263     //       ParameterToInnerFunction));
1264     if (*I > prec::Unknown)
1265       NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1266     if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) &&
1267         Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign)
1268       NewParenState.StartOfFunctionCall = State.Column;
1269 
1270     // Always indent conditional expressions. Never indent expression where
1271     // the 'operator' is ',', ';' or an assignment (i.e. *I <=
1272     // prec::Assignment) as those have different indentation rules. Indent
1273     // other expression, unless the indentation needs to be skipped.
1274     if (*I == prec::Conditional ||
1275         (!SkipFirstExtraIndent && *I > prec::Assignment &&
1276          !Current.isTrailingComment()))
1277       NewParenState.Indent += Style.ContinuationIndentWidth;
1278     if ((Previous && !Previous->opensScope()) || *I != prec::Comma)
1279       NewParenState.BreakBeforeParameter = false;
1280     State.Stack.push_back(NewParenState);
1281     SkipFirstExtraIndent = false;
1282   }
1283 }
1284 
1285 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1286   for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1287     unsigned VariablePos = State.Stack.back().VariablePos;
1288     if (State.Stack.size() == 1) {
1289       // Do not pop the last element.
1290       break;
1291     }
1292     State.Stack.pop_back();
1293     State.Stack.back().VariablePos = VariablePos;
1294   }
1295 }
1296 
1297 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1298                                                     bool Newline) {
1299   const FormatToken &Current = *State.NextToken;
1300   if (!Current.opensScope())
1301     return;
1302 
1303   if (Current.MatchingParen && Current.BlockKind == BK_Block) {
1304     moveStateToNewBlock(State);
1305     return;
1306   }
1307 
1308   unsigned NewIndent;
1309   unsigned LastSpace = State.Stack.back().LastSpace;
1310   bool AvoidBinPacking;
1311   bool BreakBeforeParameter = false;
1312   unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall,
1313                                         State.Stack.back().NestedBlockIndent);
1314   if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1315       opensProtoMessageField(Current, Style)) {
1316     if (Current.opensBlockOrBlockTypeList(Style)) {
1317       NewIndent = Style.IndentWidth +
1318                   std::min(State.Column, State.Stack.back().NestedBlockIndent);
1319     } else {
1320       NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth;
1321     }
1322     const FormatToken *NextNoComment = Current.getNextNonComment();
1323     bool EndsInComma = Current.MatchingParen &&
1324                        Current.MatchingParen->Previous &&
1325                        Current.MatchingParen->Previous->is(tok::comma);
1326     AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1327                       Style.Language == FormatStyle::LK_Proto ||
1328                       Style.Language == FormatStyle::LK_TextProto ||
1329                       !Style.BinPackArguments ||
1330                       (NextNoComment &&
1331                        NextNoComment->isOneOf(TT_DesignatedInitializerPeriod,
1332                                               TT_DesignatedInitializerLSquare));
1333     BreakBeforeParameter = EndsInComma;
1334     if (Current.ParameterCount > 1)
1335       NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1336   } else {
1337     NewIndent = Style.ContinuationIndentWidth +
1338                 std::max(State.Stack.back().LastSpace,
1339                          State.Stack.back().StartOfFunctionCall);
1340 
1341     // Ensure that different different brackets force relative alignment, e.g.:
1342     // void SomeFunction(vector<  // break
1343     //                       int> v);
1344     // FIXME: We likely want to do this for more combinations of brackets.
1345     if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1346       NewIndent = std::max(NewIndent, State.Stack.back().Indent);
1347       LastSpace = std::max(LastSpace, State.Stack.back().Indent);
1348     }
1349 
1350     bool EndsInComma =
1351         Current.MatchingParen &&
1352         Current.MatchingParen->getPreviousNonComment() &&
1353         Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1354 
1355     // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1356     // for backwards compatibility.
1357     bool ObjCBinPackProtocolList =
1358         (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1359          Style.BinPackParameters) ||
1360         Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1361 
1362     bool BinPackDeclaration =
1363         (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1364         (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1365 
1366     AvoidBinPacking =
1367         (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) ||
1368         (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1369         (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1370         (Style.ExperimentalAutoDetectBinPacking &&
1371          (Current.PackingKind == PPK_OnePerLine ||
1372           (!BinPackInconclusiveFunctions &&
1373            Current.PackingKind == PPK_Inconclusive)));
1374 
1375     if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen) {
1376       if (Style.ColumnLimit) {
1377         // If this '[' opens an ObjC call, determine whether all parameters fit
1378         // into one line and put one per line if they don't.
1379         if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1380             getColumnLimit(State))
1381           BreakBeforeParameter = true;
1382       } else {
1383         // For ColumnLimit = 0, we have to figure out whether there is or has to
1384         // be a line break within this call.
1385         for (const FormatToken *Tok = &Current;
1386              Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1387           if (Tok->MustBreakBefore ||
1388               (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1389             BreakBeforeParameter = true;
1390             break;
1391           }
1392         }
1393       }
1394     }
1395 
1396     if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma)
1397       BreakBeforeParameter = true;
1398   }
1399   // Generally inherit NoLineBreak from the current scope to nested scope.
1400   // However, don't do this for non-empty nested blocks, dict literals and
1401   // array literals as these follow different indentation rules.
1402   bool NoLineBreak =
1403       Current.Children.empty() &&
1404       !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1405       (State.Stack.back().NoLineBreak ||
1406        State.Stack.back().NoLineBreakInOperand ||
1407        (Current.is(TT_TemplateOpener) &&
1408         State.Stack.back().ContainsUnwrappedBuilder));
1409   State.Stack.push_back(
1410       ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1411   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1412   State.Stack.back().BreakBeforeParameter = BreakBeforeParameter;
1413   State.Stack.back().HasMultipleNestedBlocks = Current.BlockParameterCount > 1;
1414   State.Stack.back().IsInsideObjCArrayLiteral =
1415       Current.is(TT_ArrayInitializerLSquare) && Current.Previous &&
1416       Current.Previous->is(tok::at);
1417 }
1418 
1419 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1420   const FormatToken &Current = *State.NextToken;
1421   if (!Current.closesScope())
1422     return;
1423 
1424   // If we encounter a closing ), ], } or >, we can remove a level from our
1425   // stacks.
1426   if (State.Stack.size() > 1 &&
1427       (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1428        (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1429        State.NextToken->is(TT_TemplateCloser) ||
1430        (Current.is(tok::greater) && Current.is(TT_DictLiteral))))
1431     State.Stack.pop_back();
1432 
1433   // Reevaluate whether ObjC message arguments fit into one line.
1434   // If a receiver spans multiple lines, e.g.:
1435   //   [[object block:^{
1436   //     return 42;
1437   //   }] a:42 b:42];
1438   // BreakBeforeParameter is calculated based on an incorrect assumption
1439   // (it is checked whether the whole expression fits into one line without
1440   // considering a line break inside a message receiver).
1441   // We check whether arguements fit after receiver scope closer (into the same
1442   // line).
1443   if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen &&
1444       Current.MatchingParen->Previous) {
1445     const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1446     if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1447         CurrentScopeOpener.MatchingParen) {
1448       int NecessarySpaceInLine =
1449           getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1450           CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1451       if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1452           Style.ColumnLimit)
1453         State.Stack.back().BreakBeforeParameter = false;
1454     }
1455   }
1456 
1457   if (Current.is(tok::r_square)) {
1458     // If this ends the array subscript expr, reset the corresponding value.
1459     const FormatToken *NextNonComment = Current.getNextNonComment();
1460     if (NextNonComment && NextNonComment->isNot(tok::l_square))
1461       State.Stack.back().StartOfArraySubscripts = 0;
1462   }
1463 }
1464 
1465 void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1466   unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1467   // ObjC block sometimes follow special indentation rules.
1468   unsigned NewIndent =
1469       NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1470                                ? Style.ObjCBlockIndentWidth
1471                                : Style.IndentWidth);
1472   State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1473                                    State.Stack.back().LastSpace,
1474                                    /*AvoidBinPacking=*/true,
1475                                    /*NoLineBreak=*/false));
1476   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1477   State.Stack.back().BreakBeforeParameter = true;
1478 }
1479 
1480 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1481                                      unsigned TabWidth,
1482                                      encoding::Encoding Encoding) {
1483   size_t LastNewlinePos = Text.find_last_of("\n");
1484   if (LastNewlinePos == StringRef::npos) {
1485     return StartColumn +
1486            encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
1487   } else {
1488     return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
1489                                          /*StartColumn=*/0, TabWidth, Encoding);
1490   }
1491 }
1492 
1493 unsigned ContinuationIndenter::reformatRawStringLiteral(
1494     const FormatToken &Current, LineState &State,
1495     const FormatStyle &RawStringStyle, bool DryRun, bool Newline) {
1496   unsigned StartColumn = State.Column - Current.ColumnWidth;
1497   StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
1498   StringRef NewDelimiter =
1499       getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
1500   if (NewDelimiter.empty() || OldDelimiter.empty())
1501     NewDelimiter = OldDelimiter;
1502   // The text of a raw string is between the leading 'R"delimiter(' and the
1503   // trailing 'delimiter)"'.
1504   unsigned OldPrefixSize = 3 + OldDelimiter.size();
1505   unsigned OldSuffixSize = 2 + OldDelimiter.size();
1506   // We create a virtual text environment which expects a null-terminated
1507   // string, so we cannot use StringRef.
1508   std::string RawText =
1509       Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize);
1510   if (NewDelimiter != OldDelimiter) {
1511     // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
1512     // raw string.
1513     std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
1514     if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
1515       NewDelimiter = OldDelimiter;
1516   }
1517 
1518   unsigned NewPrefixSize = 3 + NewDelimiter.size();
1519   unsigned NewSuffixSize = 2 + NewDelimiter.size();
1520 
1521   // The first start column is the column the raw text starts after formatting.
1522   unsigned FirstStartColumn = StartColumn + NewPrefixSize;
1523 
1524   // The next start column is the intended indentation a line break inside
1525   // the raw string at level 0. It is determined by the following rules:
1526   //   - if the content starts on newline, it is one level more than the current
1527   //     indent, and
1528   //   - if the content does not start on a newline, it is the first start
1529   //     column.
1530   // These rules have the advantage that the formatted content both does not
1531   // violate the rectangle rule and visually flows within the surrounding
1532   // source.
1533   bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
1534   // If this token is the last parameter (checked by looking if it's followed by
1535   // `)` and is not on a newline, the base the indent off the line's nested
1536   // block indent. Otherwise, base the indent off the arguments indent, so we
1537   // can achieve:
1538   //
1539   // fffffffffff(1, 2, 3, R"pb(
1540   //     key1: 1  #
1541   //     key2: 2)pb");
1542   //
1543   // fffffffffff(1, 2, 3,
1544   //             R"pb(
1545   //               key1: 1  #
1546   //               key2: 2
1547   //             )pb");
1548   //
1549   // fffffffffff(1, 2, 3,
1550   //             R"pb(
1551   //               key1: 1  #
1552   //               key2: 2
1553   //             )pb",
1554   //             5);
1555   unsigned CurrentIndent =
1556       (!Newline && Current.Next && Current.Next->is(tok::r_paren))
1557           ? State.Stack.back().NestedBlockIndent
1558           : State.Stack.back().Indent;
1559   unsigned NextStartColumn = ContentStartsOnNewline
1560                                  ? CurrentIndent + Style.IndentWidth
1561                                  : FirstStartColumn;
1562 
1563   // The last start column is the column the raw string suffix starts if it is
1564   // put on a newline.
1565   // The last start column is the intended indentation of the raw string postfix
1566   // if it is put on a newline. It is determined by the following rules:
1567   //   - if the raw string prefix starts on a newline, it is the column where
1568   //     that raw string prefix starts, and
1569   //   - if the raw string prefix does not start on a newline, it is the current
1570   //     indent.
1571   unsigned LastStartColumn =
1572       Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent;
1573 
1574   std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
1575       RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
1576       FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
1577       /*Status=*/nullptr);
1578 
1579   auto NewCode = applyAllReplacements(RawText, Fixes.first);
1580   tooling::Replacements NoFixes;
1581   if (!NewCode) {
1582     return addMultilineToken(Current, State);
1583   }
1584   if (!DryRun) {
1585     if (NewDelimiter != OldDelimiter) {
1586       // In 'R"delimiter(...', the delimiter starts 2 characters after the start
1587       // of the token.
1588       SourceLocation PrefixDelimiterStart =
1589           Current.Tok.getLocation().getLocWithOffset(2);
1590       auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
1591           SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1592       if (PrefixErr) {
1593         llvm::errs()
1594             << "Failed to update the prefix delimiter of a raw string: "
1595             << llvm::toString(std::move(PrefixErr)) << "\n";
1596       }
1597       // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
1598       // position length - 1 - |delimiter|.
1599       SourceLocation SuffixDelimiterStart =
1600           Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
1601                                                      1 - OldDelimiter.size());
1602       auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
1603           SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
1604       if (SuffixErr) {
1605         llvm::errs()
1606             << "Failed to update the suffix delimiter of a raw string: "
1607             << llvm::toString(std::move(SuffixErr)) << "\n";
1608       }
1609     }
1610     SourceLocation OriginLoc =
1611         Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
1612     for (const tooling::Replacement &Fix : Fixes.first) {
1613       auto Err = Whitespaces.addReplacement(tooling::Replacement(
1614           SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
1615           Fix.getLength(), Fix.getReplacementText()));
1616       if (Err) {
1617         llvm::errs() << "Failed to reformat raw string: "
1618                      << llvm::toString(std::move(Err)) << "\n";
1619       }
1620     }
1621   }
1622   unsigned RawLastLineEndColumn = getLastLineEndColumn(
1623       *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
1624   State.Column = RawLastLineEndColumn + NewSuffixSize;
1625   // Since we're updating the column to after the raw string literal here, we
1626   // have to manually add the penalty for the prefix R"delim( over the column
1627   // limit.
1628   unsigned PrefixExcessCharacters =
1629       StartColumn + NewPrefixSize > Style.ColumnLimit
1630           ? StartColumn + NewPrefixSize - Style.ColumnLimit
1631           : 0;
1632   bool IsMultiline =
1633       ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos);
1634   if (IsMultiline) {
1635     // Break before further function parameters on all levels.
1636     for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1637       State.Stack[i].BreakBeforeParameter = true;
1638   }
1639   return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
1640 }
1641 
1642 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
1643                                                  LineState &State) {
1644   // Break before further function parameters on all levels.
1645   for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
1646     State.Stack[i].BreakBeforeParameter = true;
1647 
1648   unsigned ColumnsUsed = State.Column;
1649   // We can only affect layout of the first and the last line, so the penalty
1650   // for all other lines is constant, and we ignore it.
1651   State.Column = Current.LastLineColumnWidth;
1652 
1653   if (ColumnsUsed > getColumnLimit(State))
1654     return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
1655   return 0;
1656 }
1657 
1658 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
1659                                                LineState &State, bool DryRun,
1660                                                bool AllowBreak, bool Newline) {
1661   unsigned Penalty = 0;
1662   // Compute the raw string style to use in case this is a raw string literal
1663   // that can be reformatted.
1664   auto RawStringStyle = getRawStringStyle(Current, State);
1665   if (RawStringStyle && !Current.Finalized) {
1666     Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun,
1667                                        Newline);
1668   } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
1669     // Don't break multi-line tokens other than block comments and raw string
1670     // literals. Instead, just update the state.
1671     Penalty = addMultilineToken(Current, State);
1672   } else if (State.Line->Type != LT_ImportStatement) {
1673     // We generally don't break import statements.
1674     LineState OriginalState = State;
1675 
1676     // Whether we force the reflowing algorithm to stay strictly within the
1677     // column limit.
1678     bool Strict = false;
1679     // Whether the first non-strict attempt at reflowing did intentionally
1680     // exceed the column limit.
1681     bool Exceeded = false;
1682     std::tie(Penalty, Exceeded) = breakProtrudingToken(
1683         Current, State, AllowBreak, /*DryRun=*/true, Strict);
1684     if (Exceeded) {
1685       // If non-strict reflowing exceeds the column limit, try whether strict
1686       // reflowing leads to an overall lower penalty.
1687       LineState StrictState = OriginalState;
1688       unsigned StrictPenalty =
1689           breakProtrudingToken(Current, StrictState, AllowBreak,
1690                                /*DryRun=*/true, /*Strict=*/true)
1691               .first;
1692       Strict = StrictPenalty <= Penalty;
1693       if (Strict) {
1694         Penalty = StrictPenalty;
1695         State = StrictState;
1696       }
1697     }
1698     if (!DryRun) {
1699       // If we're not in dry-run mode, apply the changes with the decision on
1700       // strictness made above.
1701       breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
1702                            Strict);
1703     }
1704   }
1705   if (State.Column > getColumnLimit(State)) {
1706     unsigned ExcessCharacters = State.Column - getColumnLimit(State);
1707     Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
1708   }
1709   return Penalty;
1710 }
1711 
1712 // Returns the enclosing function name of a token, or the empty string if not
1713 // found.
1714 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
1715   // Look for: 'function(' or 'function<templates>(' before Current.
1716   auto Tok = Current.getPreviousNonComment();
1717   if (!Tok || !Tok->is(tok::l_paren))
1718     return "";
1719   Tok = Tok->getPreviousNonComment();
1720   if (!Tok)
1721     return "";
1722   if (Tok->is(TT_TemplateCloser)) {
1723     Tok = Tok->MatchingParen;
1724     if (Tok)
1725       Tok = Tok->getPreviousNonComment();
1726   }
1727   if (!Tok || !Tok->is(tok::identifier))
1728     return "";
1729   return Tok->TokenText;
1730 }
1731 
1732 llvm::Optional<FormatStyle>
1733 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
1734                                         const LineState &State) {
1735   if (!Current.isStringLiteral())
1736     return None;
1737   auto Delimiter = getRawStringDelimiter(Current.TokenText);
1738   if (!Delimiter)
1739     return None;
1740   auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
1741   if (!RawStringStyle && Delimiter->empty())
1742     RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
1743         getEnclosingFunctionName(Current));
1744   if (!RawStringStyle)
1745     return None;
1746   RawStringStyle->ColumnLimit = getColumnLimit(State);
1747   return RawStringStyle;
1748 }
1749 
1750 std::unique_ptr<BreakableToken>
1751 ContinuationIndenter::createBreakableToken(const FormatToken &Current,
1752                                            LineState &State, bool AllowBreak) {
1753   unsigned StartColumn = State.Column - Current.ColumnWidth;
1754   if (Current.isStringLiteral()) {
1755     // FIXME: String literal breaking is currently disabled for C#,Java and
1756     // JavaScript, as it requires strings to be merged using "+" which we
1757     // don't support.
1758     if (Style.Language == FormatStyle::LK_Java ||
1759         Style.Language == FormatStyle::LK_JavaScript || Style.isCSharp() ||
1760         !Style.BreakStringLiterals || !AllowBreak)
1761       return nullptr;
1762 
1763     // Don't break string literals inside preprocessor directives (except for
1764     // #define directives, as their contents are stored in separate lines and
1765     // are not affected by this check).
1766     // This way we avoid breaking code with line directives and unknown
1767     // preprocessor directives that contain long string literals.
1768     if (State.Line->Type == LT_PreprocessorDirective)
1769       return nullptr;
1770     // Exempts unterminated string literals from line breaking. The user will
1771     // likely want to terminate the string before any line breaking is done.
1772     if (Current.IsUnterminatedLiteral)
1773       return nullptr;
1774     // Don't break string literals inside Objective-C array literals (doing so
1775     // raises the warning -Wobjc-string-concatenation).
1776     if (State.Stack.back().IsInsideObjCArrayLiteral) {
1777       return nullptr;
1778     }
1779 
1780     StringRef Text = Current.TokenText;
1781     StringRef Prefix;
1782     StringRef Postfix;
1783     // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
1784     // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
1785     // reduce the overhead) for each FormatToken, which is a string, so that we
1786     // don't run multiple checks here on the hot path.
1787     if ((Text.endswith(Postfix = "\"") &&
1788          (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") ||
1789           Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") ||
1790           Text.startswith(Prefix = "u8\"") ||
1791           Text.startswith(Prefix = "L\""))) ||
1792         (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) {
1793       // We need this to address the case where there is an unbreakable tail
1794       // only if certain other formatting decisions have been taken. The
1795       // UnbreakableTailLength of Current is an overapproximation is that case
1796       // and we need to be correct here.
1797       unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
1798                                            ? 0
1799                                            : Current.UnbreakableTailLength;
1800       return std::make_unique<BreakableStringLiteral>(
1801           Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
1802           State.Line->InPPDirective, Encoding, Style);
1803     }
1804   } else if (Current.is(TT_BlockComment)) {
1805     if (!Style.ReflowComments ||
1806         // If a comment token switches formatting, like
1807         // /* clang-format on */, we don't want to break it further,
1808         // but we may still want to adjust its indentation.
1809         switchesFormatting(Current)) {
1810       return nullptr;
1811     }
1812     return std::make_unique<BreakableBlockComment>(
1813         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1814         State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF());
1815   } else if (Current.is(TT_LineComment) &&
1816              (Current.Previous == nullptr ||
1817               Current.Previous->isNot(TT_ImplicitStringLiteral))) {
1818     if (!Style.ReflowComments ||
1819         CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
1820         switchesFormatting(Current))
1821       return nullptr;
1822     return std::make_unique<BreakableLineCommentSection>(
1823         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
1824         /*InPPDirective=*/false, Encoding, Style);
1825   }
1826   return nullptr;
1827 }
1828 
1829 std::pair<unsigned, bool>
1830 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
1831                                            LineState &State, bool AllowBreak,
1832                                            bool DryRun, bool Strict) {
1833   std::unique_ptr<const BreakableToken> Token =
1834       createBreakableToken(Current, State, AllowBreak);
1835   if (!Token)
1836     return {0, false};
1837   assert(Token->getLineCount() > 0);
1838   unsigned ColumnLimit = getColumnLimit(State);
1839   if (Current.is(TT_LineComment)) {
1840     // We don't insert backslashes when breaking line comments.
1841     ColumnLimit = Style.ColumnLimit;
1842   }
1843   if (Current.UnbreakableTailLength >= ColumnLimit)
1844     return {0, false};
1845   // ColumnWidth was already accounted into State.Column before calling
1846   // breakProtrudingToken.
1847   unsigned StartColumn = State.Column - Current.ColumnWidth;
1848   unsigned NewBreakPenalty = Current.isStringLiteral()
1849                                  ? Style.PenaltyBreakString
1850                                  : Style.PenaltyBreakComment;
1851   // Stores whether we intentionally decide to let a line exceed the column
1852   // limit.
1853   bool Exceeded = false;
1854   // Stores whether we introduce a break anywhere in the token.
1855   bool BreakInserted = Token->introducesBreakBeforeToken();
1856   // Store whether we inserted a new line break at the end of the previous
1857   // logical line.
1858   bool NewBreakBefore = false;
1859   // We use a conservative reflowing strategy. Reflow starts after a line is
1860   // broken or the corresponding whitespace compressed. Reflow ends as soon as a
1861   // line that doesn't get reflown with the previous line is reached.
1862   bool Reflow = false;
1863   // Keep track of where we are in the token:
1864   // Where we are in the content of the current logical line.
1865   unsigned TailOffset = 0;
1866   // The column number we're currently at.
1867   unsigned ContentStartColumn =
1868       Token->getContentStartColumn(0, /*Break=*/false);
1869   // The number of columns left in the current logical line after TailOffset.
1870   unsigned RemainingTokenColumns =
1871       Token->getRemainingLength(0, TailOffset, ContentStartColumn);
1872   // Adapt the start of the token, for example indent.
1873   if (!DryRun)
1874     Token->adaptStartOfLine(0, Whitespaces);
1875 
1876   unsigned ContentIndent = 0;
1877   unsigned Penalty = 0;
1878   LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
1879                           << StartColumn << ".\n");
1880   for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
1881        LineIndex != EndIndex; ++LineIndex) {
1882     LLVM_DEBUG(llvm::dbgs()
1883                << "  Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
1884     NewBreakBefore = false;
1885     // If we did reflow the previous line, we'll try reflowing again. Otherwise
1886     // we'll start reflowing if the current line is broken or whitespace is
1887     // compressed.
1888     bool TryReflow = Reflow;
1889     // Break the current token until we can fit the rest of the line.
1890     while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
1891       LLVM_DEBUG(llvm::dbgs() << "    Over limit, need: "
1892                               << (ContentStartColumn + RemainingTokenColumns)
1893                               << ", space: " << ColumnLimit
1894                               << ", reflown prefix: " << ContentStartColumn
1895                               << ", offset in line: " << TailOffset << "\n");
1896       // If the current token doesn't fit, find the latest possible split in the
1897       // current line so that breaking at it will be under the column limit.
1898       // FIXME: Use the earliest possible split while reflowing to correctly
1899       // compress whitespace within a line.
1900       BreakableToken::Split Split =
1901           Token->getSplit(LineIndex, TailOffset, ColumnLimit,
1902                           ContentStartColumn, CommentPragmasRegex);
1903       if (Split.first == StringRef::npos) {
1904         // No break opportunity - update the penalty and continue with the next
1905         // logical line.
1906         if (LineIndex < EndIndex - 1)
1907           // The last line's penalty is handled in addNextStateToQueue() or when
1908           // calling replaceWhitespaceAfterLastLine below.
1909           Penalty += Style.PenaltyExcessCharacter *
1910                      (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
1911         LLVM_DEBUG(llvm::dbgs() << "    No break opportunity.\n");
1912         break;
1913       }
1914       assert(Split.first != 0);
1915 
1916       if (Token->supportsReflow()) {
1917         // Check whether the next natural split point after the current one can
1918         // still fit the line, either because we can compress away whitespace,
1919         // or because the penalty the excess characters introduce is lower than
1920         // the break penalty.
1921         // We only do this for tokens that support reflowing, and thus allow us
1922         // to change the whitespace arbitrarily (e.g. comments).
1923         // Other tokens, like string literals, can be broken on arbitrary
1924         // positions.
1925 
1926         // First, compute the columns from TailOffset to the next possible split
1927         // position.
1928         // For example:
1929         // ColumnLimit:     |
1930         // // Some text   that    breaks
1931         //    ^ tail offset
1932         //             ^-- split
1933         //    ^-------- to split columns
1934         //                    ^--- next split
1935         //    ^--------------- to next split columns
1936         unsigned ToSplitColumns = Token->getRangeLength(
1937             LineIndex, TailOffset, Split.first, ContentStartColumn);
1938         LLVM_DEBUG(llvm::dbgs() << "    ToSplit: " << ToSplitColumns << "\n");
1939 
1940         BreakableToken::Split NextSplit = Token->getSplit(
1941             LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
1942             ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
1943         // Compute the columns necessary to fit the next non-breakable sequence
1944         // into the current line.
1945         unsigned ToNextSplitColumns = 0;
1946         if (NextSplit.first == StringRef::npos) {
1947           ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
1948                                                          ContentStartColumn);
1949         } else {
1950           ToNextSplitColumns = Token->getRangeLength(
1951               LineIndex, TailOffset,
1952               Split.first + Split.second + NextSplit.first, ContentStartColumn);
1953         }
1954         // Compress the whitespace between the break and the start of the next
1955         // unbreakable sequence.
1956         ToNextSplitColumns =
1957             Token->getLengthAfterCompression(ToNextSplitColumns, Split);
1958         LLVM_DEBUG(llvm::dbgs()
1959                    << "    ContentStartColumn: " << ContentStartColumn << "\n");
1960         LLVM_DEBUG(llvm::dbgs()
1961                    << "    ToNextSplit: " << ToNextSplitColumns << "\n");
1962         // If the whitespace compression makes us fit, continue on the current
1963         // line.
1964         bool ContinueOnLine =
1965             ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
1966         unsigned ExcessCharactersPenalty = 0;
1967         if (!ContinueOnLine && !Strict) {
1968           // Similarly, if the excess characters' penalty is lower than the
1969           // penalty of introducing a new break, continue on the current line.
1970           ExcessCharactersPenalty =
1971               (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
1972               Style.PenaltyExcessCharacter;
1973           LLVM_DEBUG(llvm::dbgs()
1974                      << "    Penalty excess: " << ExcessCharactersPenalty
1975                      << "\n            break : " << NewBreakPenalty << "\n");
1976           if (ExcessCharactersPenalty < NewBreakPenalty) {
1977             Exceeded = true;
1978             ContinueOnLine = true;
1979           }
1980         }
1981         if (ContinueOnLine) {
1982           LLVM_DEBUG(llvm::dbgs() << "    Continuing on line...\n");
1983           // The current line fits after compressing the whitespace - reflow
1984           // the next line into it if possible.
1985           TryReflow = true;
1986           if (!DryRun)
1987             Token->compressWhitespace(LineIndex, TailOffset, Split,
1988                                       Whitespaces);
1989           // When we continue on the same line, leave one space between content.
1990           ContentStartColumn += ToSplitColumns + 1;
1991           Penalty += ExcessCharactersPenalty;
1992           TailOffset += Split.first + Split.second;
1993           RemainingTokenColumns = Token->getRemainingLength(
1994               LineIndex, TailOffset, ContentStartColumn);
1995           continue;
1996         }
1997       }
1998       LLVM_DEBUG(llvm::dbgs() << "    Breaking...\n");
1999       // Update the ContentIndent only if the current line was not reflown with
2000       // the previous line, since in that case the previous line should still
2001       // determine the ContentIndent. Also never intent the last line.
2002       if (!Reflow)
2003         ContentIndent = Token->getContentIndent(LineIndex);
2004       LLVM_DEBUG(llvm::dbgs()
2005                  << "    ContentIndent: " << ContentIndent << "\n");
2006       ContentStartColumn = ContentIndent + Token->getContentStartColumn(
2007                                                LineIndex, /*Break=*/true);
2008 
2009       unsigned NewRemainingTokenColumns = Token->getRemainingLength(
2010           LineIndex, TailOffset + Split.first + Split.second,
2011           ContentStartColumn);
2012       if (NewRemainingTokenColumns == 0) {
2013         // No content to indent.
2014         ContentIndent = 0;
2015         ContentStartColumn =
2016             Token->getContentStartColumn(LineIndex, /*Break=*/true);
2017         NewRemainingTokenColumns = Token->getRemainingLength(
2018             LineIndex, TailOffset + Split.first + Split.second,
2019             ContentStartColumn);
2020       }
2021 
2022       // When breaking before a tab character, it may be moved by a few columns,
2023       // but will still be expanded to the next tab stop, so we don't save any
2024       // columns.
2025       if (NewRemainingTokenColumns == RemainingTokenColumns) {
2026         // FIXME: Do we need to adjust the penalty?
2027         break;
2028       }
2029       assert(NewRemainingTokenColumns < RemainingTokenColumns);
2030 
2031       LLVM_DEBUG(llvm::dbgs() << "    Breaking at: " << TailOffset + Split.first
2032                               << ", " << Split.second << "\n");
2033       if (!DryRun)
2034         Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
2035                            Whitespaces);
2036 
2037       Penalty += NewBreakPenalty;
2038       TailOffset += Split.first + Split.second;
2039       RemainingTokenColumns = NewRemainingTokenColumns;
2040       BreakInserted = true;
2041       NewBreakBefore = true;
2042     }
2043     // In case there's another line, prepare the state for the start of the next
2044     // line.
2045     if (LineIndex + 1 != EndIndex) {
2046       unsigned NextLineIndex = LineIndex + 1;
2047       if (NewBreakBefore)
2048         // After breaking a line, try to reflow the next line into the current
2049         // one once RemainingTokenColumns fits.
2050         TryReflow = true;
2051       if (TryReflow) {
2052         // We decided that we want to try reflowing the next line into the
2053         // current one.
2054         // We will now adjust the state as if the reflow is successful (in
2055         // preparation for the next line), and see whether that works. If we
2056         // decide that we cannot reflow, we will later reset the state to the
2057         // start of the next line.
2058         Reflow = false;
2059         // As we did not continue breaking the line, RemainingTokenColumns is
2060         // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2061         // the position at which we want to format the next line if we do
2062         // actually reflow.
2063         // When we reflow, we need to add a space between the end of the current
2064         // line and the next line's start column.
2065         ContentStartColumn += RemainingTokenColumns + 1;
2066         // Get the split that we need to reflow next logical line into the end
2067         // of the current one; the split will include any leading whitespace of
2068         // the next logical line.
2069         BreakableToken::Split SplitBeforeNext =
2070             Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2071         LLVM_DEBUG(llvm::dbgs()
2072                    << "    Size of reflown text: " << ContentStartColumn
2073                    << "\n    Potential reflow split: ");
2074         if (SplitBeforeNext.first != StringRef::npos) {
2075           LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2076                                   << SplitBeforeNext.second << "\n");
2077           TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2078           // If the rest of the next line fits into the current line below the
2079           // column limit, we can safely reflow.
2080           RemainingTokenColumns = Token->getRemainingLength(
2081               NextLineIndex, TailOffset, ContentStartColumn);
2082           Reflow = true;
2083           if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2084             LLVM_DEBUG(llvm::dbgs()
2085                        << "    Over limit after reflow, need: "
2086                        << (ContentStartColumn + RemainingTokenColumns)
2087                        << ", space: " << ColumnLimit
2088                        << ", reflown prefix: " << ContentStartColumn
2089                        << ", offset in line: " << TailOffset << "\n");
2090             // If the whole next line does not fit, try to find a point in
2091             // the next line at which we can break so that attaching the part
2092             // of the next line to that break point onto the current line is
2093             // below the column limit.
2094             BreakableToken::Split Split =
2095                 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2096                                 ContentStartColumn, CommentPragmasRegex);
2097             if (Split.first == StringRef::npos) {
2098               LLVM_DEBUG(llvm::dbgs() << "    Did not find later break\n");
2099               Reflow = false;
2100             } else {
2101               // Check whether the first split point gets us below the column
2102               // limit. Note that we will execute this split below as part of
2103               // the normal token breaking and reflow logic within the line.
2104               unsigned ToSplitColumns = Token->getRangeLength(
2105                   NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2106               if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2107                 LLVM_DEBUG(llvm::dbgs() << "    Next split protrudes, need: "
2108                                         << (ContentStartColumn + ToSplitColumns)
2109                                         << ", space: " << ColumnLimit);
2110                 unsigned ExcessCharactersPenalty =
2111                     (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2112                     Style.PenaltyExcessCharacter;
2113                 if (NewBreakPenalty < ExcessCharactersPenalty) {
2114                   Reflow = false;
2115                 }
2116               }
2117             }
2118           }
2119         } else {
2120           LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2121         }
2122       }
2123       if (!Reflow) {
2124         // If we didn't reflow into the next line, the only space to consider is
2125         // the next logical line. Reset our state to match the start of the next
2126         // line.
2127         TailOffset = 0;
2128         ContentStartColumn =
2129             Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2130         RemainingTokenColumns = Token->getRemainingLength(
2131             NextLineIndex, TailOffset, ContentStartColumn);
2132         // Adapt the start of the token, for example indent.
2133         if (!DryRun)
2134           Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2135       } else {
2136         // If we found a reflow split and have added a new break before the next
2137         // line, we are going to remove the line break at the start of the next
2138         // logical line. For example, here we'll add a new line break after
2139         // 'text', and subsequently delete the line break between 'that' and
2140         // 'reflows'.
2141         //   // some text that
2142         //   // reflows
2143         // ->
2144         //   // some text
2145         //   // that reflows
2146         // When adding the line break, we also added the penalty for it, so we
2147         // need to subtract that penalty again when we remove the line break due
2148         // to reflowing.
2149         if (NewBreakBefore) {
2150           assert(Penalty >= NewBreakPenalty);
2151           Penalty -= NewBreakPenalty;
2152         }
2153         if (!DryRun)
2154           Token->reflow(NextLineIndex, Whitespaces);
2155       }
2156     }
2157   }
2158 
2159   BreakableToken::Split SplitAfterLastLine =
2160       Token->getSplitAfterLastLine(TailOffset);
2161   if (SplitAfterLastLine.first != StringRef::npos) {
2162     LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2163 
2164     // We add the last line's penalty here, since that line is going to be split
2165     // now.
2166     Penalty += Style.PenaltyExcessCharacter *
2167                (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2168 
2169     if (!DryRun)
2170       Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2171                                             Whitespaces);
2172     ContentStartColumn =
2173         Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2174     RemainingTokenColumns = Token->getRemainingLength(
2175         Token->getLineCount() - 1,
2176         TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2177         ContentStartColumn);
2178   }
2179 
2180   State.Column = ContentStartColumn + RemainingTokenColumns -
2181                  Current.UnbreakableTailLength;
2182 
2183   if (BreakInserted) {
2184     // If we break the token inside a parameter list, we need to break before
2185     // the next parameter on all levels, so that the next parameter is clearly
2186     // visible. Line comments already introduce a break.
2187     if (Current.isNot(TT_LineComment)) {
2188       for (unsigned i = 0, e = State.Stack.size(); i != e; ++i)
2189         State.Stack[i].BreakBeforeParameter = true;
2190     }
2191 
2192     if (Current.is(TT_BlockComment))
2193       State.NoContinuation = true;
2194 
2195     State.Stack.back().LastSpace = StartColumn;
2196   }
2197 
2198   Token->updateNextToken(State);
2199 
2200   return {Penalty, Exceeded};
2201 }
2202 
2203 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2204   // In preprocessor directives reserve two chars for trailing " \"
2205   return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2206 }
2207 
2208 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2209   const FormatToken &Current = *State.NextToken;
2210   if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2211     return false;
2212   // We never consider raw string literals "multiline" for the purpose of
2213   // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2214   // (see TokenAnnotator::mustBreakBefore().
2215   if (Current.TokenText.startswith("R\""))
2216     return false;
2217   if (Current.IsMultiline)
2218     return true;
2219   if (Current.getNextNonComment() &&
2220       Current.getNextNonComment()->isStringLiteral())
2221     return true; // Implicit concatenation.
2222   if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2223       State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2224           Style.ColumnLimit)
2225     return true; // String will be split.
2226   return false;
2227 }
2228 
2229 } // namespace format
2230 } // namespace clang
2231