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