xref: /freebsd/contrib/llvm-project/clang/lib/Format/ContinuationIndenter.cpp (revision e1e636193db45630c7881246d25902e57c43d24e)
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 "FormatToken.h"
18 #include "WhitespaceManager.h"
19 #include "clang/Basic/OperatorPrecedence.h"
20 #include "clang/Basic/SourceManager.h"
21 #include "clang/Basic/TokenKinds.h"
22 #include "clang/Format/Format.h"
23 #include "llvm/ADT/StringSet.h"
24 #include "llvm/Support/Debug.h"
25 #include <optional>
26 
27 #define DEBUG_TYPE "format-indenter"
28 
29 namespace clang {
30 namespace format {
31 
32 // Returns true if a TT_SelectorName should be indented when wrapped,
33 // false otherwise.
34 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
35                                             LineType LineType) {
36   return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl;
37 }
38 
39 // Returns true if a binary operator following \p Tok should be unindented when
40 // the style permits it.
41 static bool shouldUnindentNextOperator(const FormatToken &Tok) {
42   const FormatToken *Previous = Tok.getPreviousNonComment();
43   return Previous && (Previous->getPrecedence() == prec::Assignment ||
44                       Previous->isOneOf(tok::kw_return, TT_RequiresClause));
45 }
46 
47 // Returns the length of everything up to the first possible line break after
48 // the ), ], } or > matching \c Tok.
49 static unsigned getLengthToMatchingParen(const FormatToken &Tok,
50                                          ArrayRef<ParenState> Stack) {
51   // Normally whether or not a break before T is possible is calculated and
52   // stored in T.CanBreakBefore. Braces, array initializers and text proto
53   // messages like `key: < ... >` are an exception: a break is possible
54   // before a closing brace R if a break was inserted after the corresponding
55   // opening brace. The information about whether or not a break is needed
56   // before a closing brace R is stored in the ParenState field
57   // S.BreakBeforeClosingBrace where S is the state that R closes.
58   //
59   // In order to decide whether there can be a break before encountered right
60   // braces, this implementation iterates over the sequence of tokens and over
61   // the paren stack in lockstep, keeping track of the stack level which visited
62   // right braces correspond to in MatchingStackIndex.
63   //
64   // For example, consider:
65   // L. <- line number
66   // 1. {
67   // 2. {1},
68   // 3. {2},
69   // 4. {{3}}}
70   //     ^ where we call this method with this token.
71   // The paren stack at this point contains 3 brace levels:
72   //  0. { at line 1, BreakBeforeClosingBrace: true
73   //  1. first { at line 4, BreakBeforeClosingBrace: false
74   //  2. second { at line 4, BreakBeforeClosingBrace: false,
75   //  where there might be fake parens levels in-between these levels.
76   // The algorithm will start at the first } on line 4, which is the matching
77   // brace of the initial left brace and at level 2 of the stack. Then,
78   // examining BreakBeforeClosingBrace: false at level 2, it will continue to
79   // the second } on line 4, and will traverse the stack downwards until it
80   // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace:
81   // false at level 1, it will continue to the third } on line 4 and will
82   // traverse the stack downwards until it finds the matching { on level 0.
83   // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm
84   // will stop and will use the second } on line 4 to determine the length to
85   // return, as in this example the range will include the tokens: {3}}
86   //
87   // The algorithm will only traverse the stack if it encounters braces, array
88   // initializer squares or text proto angle brackets.
89   if (!Tok.MatchingParen)
90     return 0;
91   FormatToken *End = Tok.MatchingParen;
92   // Maintains a stack level corresponding to the current End token.
93   int MatchingStackIndex = Stack.size() - 1;
94   // Traverses the stack downwards, looking for the level to which LBrace
95   // corresponds. Returns either a pointer to the matching level or nullptr if
96   // LParen is not found in the initial portion of the stack up to
97   // MatchingStackIndex.
98   auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * {
99     while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace)
100       --MatchingStackIndex;
101     return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr;
102   };
103   for (; End->Next; End = End->Next) {
104     if (End->Next->CanBreakBefore)
105       break;
106     if (!End->Next->closesScope())
107       continue;
108     if (End->Next->MatchingParen &&
109         End->Next->MatchingParen->isOneOf(
110             tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) {
111       const ParenState *State = FindParenState(End->Next->MatchingParen);
112       if (State && State->BreakBeforeClosingBrace)
113         break;
114     }
115   }
116   return End->TotalLength - Tok.TotalLength + 1;
117 }
118 
119 static unsigned getLengthToNextOperator(const FormatToken &Tok) {
120   if (!Tok.NextOperator)
121     return 0;
122   return Tok.NextOperator->TotalLength - Tok.TotalLength;
123 }
124 
125 // Returns \c true if \c Tok is the "." or "->" of a call and starts the next
126 // segment of a builder type call.
127 static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) {
128   return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope();
129 }
130 
131 // Returns \c true if \c Current starts a new parameter.
132 static bool startsNextParameter(const FormatToken &Current,
133                                 const FormatStyle &Style) {
134   const FormatToken &Previous = *Current.Previous;
135   if (Current.is(TT_CtorInitializerComma) &&
136       Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma) {
137     return true;
138   }
139   if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName))
140     return true;
141   return Previous.is(tok::comma) && !Current.isTrailingComment() &&
142          ((Previous.isNot(TT_CtorInitializerComma) ||
143            Style.BreakConstructorInitializers !=
144                FormatStyle::BCIS_BeforeComma) &&
145           (Previous.isNot(TT_InheritanceComma) ||
146            Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma));
147 }
148 
149 static bool opensProtoMessageField(const FormatToken &LessTok,
150                                    const FormatStyle &Style) {
151   if (LessTok.isNot(tok::less))
152     return false;
153   return Style.Language == FormatStyle::LK_TextProto ||
154          (Style.Language == FormatStyle::LK_Proto &&
155           (LessTok.NestingLevel > 0 ||
156            (LessTok.Previous && LessTok.Previous->is(tok::equal))));
157 }
158 
159 // Returns the delimiter of a raw string literal, or std::nullopt if TokenText
160 // is not the text of a raw string literal. The delimiter could be the empty
161 // string.  For example, the delimiter of R"deli(cont)deli" is deli.
162 static std::optional<StringRef> getRawStringDelimiter(StringRef TokenText) {
163   if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'.
164       || !TokenText.starts_with("R\"") || !TokenText.ends_with("\"")) {
165     return std::nullopt;
166   }
167 
168   // A raw string starts with 'R"<delimiter>(' and delimiter is ascii and has
169   // size at most 16 by the standard, so the first '(' must be among the first
170   // 19 bytes.
171   size_t LParenPos = TokenText.substr(0, 19).find_first_of('(');
172   if (LParenPos == StringRef::npos)
173     return std::nullopt;
174   StringRef Delimiter = TokenText.substr(2, LParenPos - 2);
175 
176   // Check that the string ends in ')Delimiter"'.
177   size_t RParenPos = TokenText.size() - Delimiter.size() - 2;
178   if (TokenText[RParenPos] != ')')
179     return std::nullopt;
180   if (!TokenText.substr(RParenPos + 1).starts_with(Delimiter))
181     return std::nullopt;
182   return Delimiter;
183 }
184 
185 // Returns the canonical delimiter for \p Language, or the empty string if no
186 // canonical delimiter is specified.
187 static StringRef
188 getCanonicalRawStringDelimiter(const FormatStyle &Style,
189                                FormatStyle::LanguageKind Language) {
190   for (const auto &Format : Style.RawStringFormats)
191     if (Format.Language == Language)
192       return StringRef(Format.CanonicalDelimiter);
193   return "";
194 }
195 
196 RawStringFormatStyleManager::RawStringFormatStyleManager(
197     const FormatStyle &CodeStyle) {
198   for (const auto &RawStringFormat : CodeStyle.RawStringFormats) {
199     std::optional<FormatStyle> LanguageStyle =
200         CodeStyle.GetLanguageStyle(RawStringFormat.Language);
201     if (!LanguageStyle) {
202       FormatStyle PredefinedStyle;
203       if (!getPredefinedStyle(RawStringFormat.BasedOnStyle,
204                               RawStringFormat.Language, &PredefinedStyle)) {
205         PredefinedStyle = getLLVMStyle();
206         PredefinedStyle.Language = RawStringFormat.Language;
207       }
208       LanguageStyle = PredefinedStyle;
209     }
210     LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit;
211     for (StringRef Delimiter : RawStringFormat.Delimiters)
212       DelimiterStyle.insert({Delimiter, *LanguageStyle});
213     for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions)
214       EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle});
215   }
216 }
217 
218 std::optional<FormatStyle>
219 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
220   auto It = DelimiterStyle.find(Delimiter);
221   if (It == DelimiterStyle.end())
222     return std::nullopt;
223   return It->second;
224 }
225 
226 std::optional<FormatStyle>
227 RawStringFormatStyleManager::getEnclosingFunctionStyle(
228     StringRef EnclosingFunction) const {
229   auto It = EnclosingFunctionStyle.find(EnclosingFunction);
230   if (It == EnclosingFunctionStyle.end())
231     return std::nullopt;
232   return It->second;
233 }
234 
235 ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style,
236                                            const AdditionalKeywords &Keywords,
237                                            const SourceManager &SourceMgr,
238                                            WhitespaceManager &Whitespaces,
239                                            encoding::Encoding Encoding,
240                                            bool BinPackInconclusiveFunctions)
241     : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr),
242       Whitespaces(Whitespaces), Encoding(Encoding),
243       BinPackInconclusiveFunctions(BinPackInconclusiveFunctions),
244       CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {}
245 
246 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent,
247                                                 unsigned FirstStartColumn,
248                                                 const AnnotatedLine *Line,
249                                                 bool DryRun) {
250   LineState State;
251   State.FirstIndent = FirstIndent;
252   if (FirstStartColumn && Line->First->NewlinesBefore == 0)
253     State.Column = FirstStartColumn;
254   else
255     State.Column = FirstIndent;
256   // With preprocessor directive indentation, the line starts on column 0
257   // since it's indented after the hash, but FirstIndent is set to the
258   // preprocessor indent.
259   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
260       (Line->Type == LT_PreprocessorDirective ||
261        Line->Type == LT_ImportStatement)) {
262     State.Column = 0;
263   }
264   State.Line = Line;
265   State.NextToken = Line->First;
266   State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent,
267                                    /*AvoidBinPacking=*/false,
268                                    /*NoLineBreak=*/false));
269   State.NoContinuation = false;
270   State.StartOfStringLiteral = 0;
271   State.NoLineBreak = false;
272   State.StartOfLineLevel = 0;
273   State.LowestLevelOnLine = 0;
274   State.IgnoreStackForComparison = false;
275 
276   if (Style.Language == FormatStyle::LK_TextProto) {
277     // We need this in order to deal with the bin packing of text fields at
278     // global scope.
279     auto &CurrentState = State.Stack.back();
280     CurrentState.AvoidBinPacking = true;
281     CurrentState.BreakBeforeParameter = true;
282     CurrentState.AlignColons = false;
283   }
284 
285   // The first token has already been indented and thus consumed.
286   moveStateToNextToken(State, DryRun, /*Newline=*/false);
287   return State;
288 }
289 
290 bool ContinuationIndenter::canBreak(const LineState &State) {
291   const FormatToken &Current = *State.NextToken;
292   const FormatToken &Previous = *Current.Previous;
293   const auto &CurrentState = State.Stack.back();
294   assert(&Previous == Current.Previous);
295   if (!Current.CanBreakBefore && !(CurrentState.BreakBeforeClosingBrace &&
296                                    Current.closesBlockOrBlockTypeList(Style))) {
297     return false;
298   }
299   // The opening "{" of a braced list has to be on the same line as the first
300   // element if it is nested in another braced init list or function call.
301   if (!Current.MustBreakBefore && Previous.is(tok::l_brace) &&
302       Previous.isNot(TT_DictLiteral) && Previous.is(BK_BracedInit) &&
303       Previous.Previous &&
304       Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma)) {
305     return false;
306   }
307   // This prevents breaks like:
308   //   ...
309   //   SomeParameter, OtherParameter).DoSomething(
310   //   ...
311   // As they hide "DoSomething" and are generally bad for readability.
312   if (Previous.opensScope() && Previous.isNot(tok::l_brace) &&
313       State.LowestLevelOnLine < State.StartOfLineLevel &&
314       State.LowestLevelOnLine < Current.NestingLevel) {
315     return false;
316   }
317   if (Current.isMemberAccess() && CurrentState.ContainsUnwrappedBuilder)
318     return false;
319 
320   // Don't create a 'hanging' indent if there are multiple blocks in a single
321   // statement and we are aligning lambda blocks to their signatures.
322   if (Previous.is(tok::l_brace) && State.Stack.size() > 1 &&
323       State.Stack[State.Stack.size() - 2].NestedBlockInlined &&
324       State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks &&
325       Style.LambdaBodyIndentation == FormatStyle::LBI_Signature) {
326     return false;
327   }
328 
329   // Don't break after very short return types (e.g. "void") as that is often
330   // unexpected.
331   if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) {
332     if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None)
333       return false;
334   }
335 
336   // If binary operators are moved to the next line (including commas for some
337   // styles of constructor initializers), that's always ok.
338   if (!Current.isOneOf(TT_BinaryOperator, tok::comma) &&
339       // Allow breaking opening brace of lambdas (when passed as function
340       // arguments) to a new line when BeforeLambdaBody brace wrapping is
341       // enabled.
342       (!Style.BraceWrapping.BeforeLambdaBody ||
343        Current.isNot(TT_LambdaLBrace)) &&
344       CurrentState.NoLineBreakInOperand) {
345     return false;
346   }
347 
348   if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr))
349     return false;
350 
351   if (Current.is(TT_ConditionalExpr) && Previous.is(tok::r_paren) &&
352       Previous.MatchingParen && Previous.MatchingParen->Previous &&
353       Previous.MatchingParen->Previous->MatchingParen &&
354       Previous.MatchingParen->Previous->MatchingParen->is(TT_LambdaLBrace)) {
355     // We have a lambda within a conditional expression, allow breaking here.
356     assert(Previous.MatchingParen->Previous->is(tok::r_brace));
357     return true;
358   }
359 
360   return !State.NoLineBreak && !CurrentState.NoLineBreak;
361 }
362 
363 bool ContinuationIndenter::mustBreak(const LineState &State) {
364   const FormatToken &Current = *State.NextToken;
365   const FormatToken &Previous = *Current.Previous;
366   const auto &CurrentState = State.Stack.back();
367   if (Style.BraceWrapping.BeforeLambdaBody && Current.CanBreakBefore &&
368       Current.is(TT_LambdaLBrace) && Previous.isNot(TT_LineComment)) {
369     auto LambdaBodyLength = getLengthToMatchingParen(Current, State.Stack);
370     return LambdaBodyLength > getColumnLimit(State);
371   }
372   if (Current.MustBreakBefore ||
373       (Current.is(TT_InlineASMColon) &&
374        (Style.BreakBeforeInlineASMColon == FormatStyle::BBIAS_Always ||
375         (Style.BreakBeforeInlineASMColon == FormatStyle::BBIAS_OnlyMultiline &&
376          Style.ColumnLimit > 0)))) {
377     return true;
378   }
379   if (CurrentState.BreakBeforeClosingBrace &&
380       (Current.closesBlockOrBlockTypeList(Style) ||
381        (Current.is(tok::r_brace) &&
382         Current.isBlockIndentedInitRBrace(Style)))) {
383     return true;
384   }
385   if (CurrentState.BreakBeforeClosingParen && Current.is(tok::r_paren))
386     return true;
387   if (Style.Language == FormatStyle::LK_ObjC &&
388       Style.ObjCBreakBeforeNestedBlockParam &&
389       Current.ObjCSelectorNameParts > 1 &&
390       Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) {
391     return true;
392   }
393   // Avoid producing inconsistent states by requiring breaks where they are not
394   // permitted for C# generic type constraints.
395   if (CurrentState.IsCSharpGenericTypeConstraint &&
396       Previous.isNot(TT_CSharpGenericTypeConstraintComma)) {
397     return false;
398   }
399   if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
400        (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
401         State.Line->First->isNot(TT_AttributeSquare) && Style.isCpp() &&
402         // FIXME: This is a temporary workaround for the case where clang-format
403         // sets BreakBeforeParameter to avoid bin packing and this creates a
404         // completely unnecessary line break after a template type that isn't
405         // line-wrapped.
406         (Previous.NestingLevel == 1 || Style.BinPackParameters)) ||
407        (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
408         Previous.isNot(tok::question)) ||
409        (!Style.BreakBeforeTernaryOperators &&
410         Previous.is(TT_ConditionalExpr))) &&
411       CurrentState.BreakBeforeParameter && !Current.isTrailingComment() &&
412       !Current.isOneOf(tok::r_paren, tok::r_brace)) {
413     return true;
414   }
415   if (CurrentState.IsChainedConditional &&
416       ((Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
417         Current.is(tok::colon)) ||
418        (!Style.BreakBeforeTernaryOperators && Previous.is(TT_ConditionalExpr) &&
419         Previous.is(tok::colon)))) {
420     return true;
421   }
422   if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) ||
423        (Previous.is(TT_ArrayInitializerLSquare) &&
424         Previous.ParameterCount > 1) ||
425        opensProtoMessageField(Previous, Style)) &&
426       Style.ColumnLimit > 0 &&
427       getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 >
428           getColumnLimit(State)) {
429     return true;
430   }
431 
432   const FormatToken &BreakConstructorInitializersToken =
433       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon
434           ? Previous
435           : Current;
436   if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) &&
437       (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
438            getColumnLimit(State) ||
439        CurrentState.BreakBeforeParameter) &&
440       (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
441       (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All ||
442        Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
443        Style.ColumnLimit != 0)) {
444     return true;
445   }
446 
447   if (Current.is(TT_ObjCMethodExpr) && Previous.isNot(TT_SelectorName) &&
448       State.Line->startsWith(TT_ObjCMethodSpecifier)) {
449     return true;
450   }
451   if (Current.is(TT_SelectorName) && Previous.isNot(tok::at) &&
452       CurrentState.ObjCSelectorNameFound && CurrentState.BreakBeforeParameter &&
453       (Style.ObjCBreakBeforeNestedBlockParam ||
454        !Current.startsSequence(TT_SelectorName, tok::colon, tok::caret))) {
455     return true;
456   }
457 
458   unsigned NewLineColumn = getNewLineColumn(State);
459   if (Current.isMemberAccess() && Style.ColumnLimit != 0 &&
460       State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit &&
461       (State.Column > NewLineColumn ||
462        Current.NestingLevel < State.StartOfLineLevel)) {
463     return true;
464   }
465 
466   if (startsSegmentOfBuilderTypeCall(Current) &&
467       (CurrentState.CallContinuation != 0 ||
468        CurrentState.BreakBeforeParameter) &&
469       // JavaScript is treated different here as there is a frequent pattern:
470       //   SomeFunction(function() {
471       //     ...
472       //   }.bind(...));
473       // FIXME: We should find a more generic solution to this problem.
474       !(State.Column <= NewLineColumn && Style.isJavaScript()) &&
475       !(Previous.closesScopeAfterBlock() && State.Column <= NewLineColumn)) {
476     return true;
477   }
478 
479   // If the template declaration spans multiple lines, force wrap before the
480   // function/class declaration.
481   if (Previous.ClosesTemplateDeclaration && CurrentState.BreakBeforeParameter &&
482       Current.CanBreakBefore) {
483     return true;
484   }
485 
486   if (State.Line->First->isNot(tok::kw_enum) && State.Column <= NewLineColumn)
487     return false;
488 
489   if (Style.AlwaysBreakBeforeMultilineStrings &&
490       (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth ||
491        Previous.is(tok::comma) || Current.NestingLevel < 2) &&
492       !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at,
493                         Keywords.kw_dollar) &&
494       !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
495       nextIsMultilineString(State)) {
496     return true;
497   }
498 
499   // Using CanBreakBefore here and below takes care of the decision whether the
500   // current style uses wrapping before or after operators for the given
501   // operator.
502   if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
503     const auto PreviousPrecedence = Previous.getPrecedence();
504     if (PreviousPrecedence != prec::Assignment &&
505         CurrentState.BreakBeforeParameter && !Current.isTrailingComment()) {
506       const bool LHSIsBinaryExpr =
507           Previous.Previous && Previous.Previous->EndsBinaryExpression;
508       if (LHSIsBinaryExpr)
509         return true;
510       // If we need to break somewhere inside the LHS of a binary expression, we
511       // should also break after the operator. Otherwise, the formatting would
512       // hide the operator precedence, e.g. in:
513       //   if (aaaaaaaaaaaaaa ==
514       //           bbbbbbbbbbbbbb && c) {..
515       // For comparisons, we only apply this rule, if the LHS is a binary
516       // expression itself as otherwise, the line breaks seem superfluous.
517       // We need special cases for ">>" which we have split into two ">" while
518       // lexing in order to make template parsing easier.
519       const bool IsComparison =
520           (PreviousPrecedence == prec::Relational ||
521            PreviousPrecedence == prec::Equality ||
522            PreviousPrecedence == prec::Spaceship) &&
523           Previous.Previous &&
524           Previous.Previous->isNot(TT_BinaryOperator); // For >>.
525       if (!IsComparison)
526         return true;
527     }
528   } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
529              CurrentState.BreakBeforeParameter) {
530     return true;
531   }
532 
533   // Same as above, but for the first "<<" operator.
534   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
535       CurrentState.BreakBeforeParameter && CurrentState.FirstLessLess == 0) {
536     return true;
537   }
538 
539   if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
540     // Always break after "template <...>"(*) and leading annotations. This is
541     // only for cases where the entire line does not fit on a single line as a
542     // different LineFormatter would be used otherwise.
543     // *: Except when another option interferes with that, like concepts.
544     if (Previous.ClosesTemplateDeclaration) {
545       if (Current.is(tok::kw_concept)) {
546         switch (Style.BreakBeforeConceptDeclarations) {
547         case FormatStyle::BBCDS_Allowed:
548           break;
549         case FormatStyle::BBCDS_Always:
550           return true;
551         case FormatStyle::BBCDS_Never:
552           return false;
553         }
554       }
555       if (Current.is(TT_RequiresClause)) {
556         switch (Style.RequiresClausePosition) {
557         case FormatStyle::RCPS_SingleLine:
558         case FormatStyle::RCPS_WithPreceding:
559           return false;
560         default:
561           return true;
562         }
563       }
564       return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No;
565     }
566     if (Previous.is(TT_FunctionAnnotationRParen) &&
567         State.Line->Type != LT_PreprocessorDirective) {
568       return true;
569     }
570     if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
571         Current.isNot(TT_LeadingJavaAnnotation)) {
572       return true;
573     }
574   }
575 
576   if (Style.isJavaScript() && Previous.is(tok::r_paren) &&
577       Previous.is(TT_JavaAnnotation)) {
578     // Break after the closing parenthesis of TypeScript decorators before
579     // functions, getters and setters.
580     static const llvm::StringSet<> BreakBeforeDecoratedTokens = {"get", "set",
581                                                                  "function"};
582     if (BreakBeforeDecoratedTokens.contains(Current.TokenText))
583       return true;
584   }
585 
586   if (Current.is(TT_FunctionDeclarationName) &&
587       !State.Line->ReturnTypeWrapped &&
588       // Don't break before a C# function when no break after return type.
589       (!Style.isCSharp() ||
590        Style.AlwaysBreakAfterReturnType != FormatStyle::RTBS_None) &&
591       // Don't always break between a JavaScript `function` and the function
592       // name.
593       !Style.isJavaScript() && Previous.isNot(tok::kw_template) &&
594       CurrentState.BreakBeforeParameter) {
595     return true;
596   }
597 
598   // The following could be precomputed as they do not depend on the state.
599   // However, as they should take effect only if the UnwrappedLine does not fit
600   // into the ColumnLimit, they are checked here in the ContinuationIndenter.
601   if (Style.ColumnLimit != 0 && Previous.is(BK_Block) &&
602       Previous.is(tok::l_brace) &&
603       !Current.isOneOf(tok::r_brace, tok::comment)) {
604     return true;
605   }
606 
607   if (Current.is(tok::lessless) &&
608       ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
609        (Previous.Tok.isLiteral() && (Previous.TokenText.ends_with("\\n\"") ||
610                                      Previous.TokenText == "\'\\n\'")))) {
611     return true;
612   }
613 
614   if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
615     return true;
616 
617   if (State.NoContinuation)
618     return true;
619 
620   return false;
621 }
622 
623 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
624                                                bool DryRun,
625                                                unsigned ExtraSpaces) {
626   const FormatToken &Current = *State.NextToken;
627   assert(State.NextToken->Previous);
628   const FormatToken &Previous = *State.NextToken->Previous;
629 
630   assert(!State.Stack.empty());
631   State.NoContinuation = false;
632 
633   if (Current.is(TT_ImplicitStringLiteral) &&
634       (!Previous.Tok.getIdentifierInfo() ||
635        Previous.Tok.getIdentifierInfo()->getPPKeywordID() ==
636            tok::pp_not_keyword)) {
637     unsigned EndColumn =
638         SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
639     if (Current.LastNewlineOffset != 0) {
640       // If there is a newline within this token, the final column will solely
641       // determined by the current end column.
642       State.Column = EndColumn;
643     } else {
644       unsigned StartColumn =
645           SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
646       assert(EndColumn >= StartColumn);
647       State.Column += EndColumn - StartColumn;
648     }
649     moveStateToNextToken(State, DryRun, /*Newline=*/false);
650     return 0;
651   }
652 
653   unsigned Penalty = 0;
654   if (Newline)
655     Penalty = addTokenOnNewLine(State, DryRun);
656   else
657     addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
658 
659   return moveStateToNextToken(State, DryRun, Newline) + Penalty;
660 }
661 
662 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
663                                                  unsigned ExtraSpaces) {
664   FormatToken &Current = *State.NextToken;
665   assert(State.NextToken->Previous);
666   const FormatToken &Previous = *State.NextToken->Previous;
667   auto &CurrentState = State.Stack.back();
668 
669   bool DisallowLineBreaksOnThisLine =
670       Style.LambdaBodyIndentation == FormatStyle::LBI_Signature &&
671       Style.isCpp() && [&Current] {
672         // Deal with lambda arguments in C++. The aim here is to ensure that we
673         // don't over-indent lambda function bodies when lambdas are passed as
674         // arguments to function calls. We do this by ensuring that either all
675         // arguments (including any lambdas) go on the same line as the function
676         // call, or we break before the first argument.
677         auto PrevNonComment = Current.getPreviousNonComment();
678         if (!PrevNonComment || PrevNonComment->isNot(tok::l_paren))
679           return false;
680         if (Current.isOneOf(tok::comment, tok::l_paren, TT_LambdaLSquare))
681           return false;
682         auto BlockParameterCount = PrevNonComment->BlockParameterCount;
683         if (BlockParameterCount == 0)
684           return false;
685 
686         // Multiple lambdas in the same function call.
687         if (BlockParameterCount > 1)
688           return true;
689 
690         // A lambda followed by another arg.
691         if (!PrevNonComment->Role)
692           return false;
693         auto Comma = PrevNonComment->Role->lastComma();
694         if (!Comma)
695           return false;
696         auto Next = Comma->getNextNonComment();
697         return Next &&
698                !Next->isOneOf(TT_LambdaLSquare, tok::l_brace, tok::caret);
699       }();
700 
701   if (DisallowLineBreaksOnThisLine)
702     State.NoLineBreak = true;
703 
704   if (Current.is(tok::equal) &&
705       (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
706       CurrentState.VariablePos == 0 &&
707       (!Previous.Previous ||
708        Previous.Previous->isNot(TT_DesignatedInitializerPeriod))) {
709     CurrentState.VariablePos = State.Column;
710     // Move over * and & if they are bound to the variable name.
711     const FormatToken *Tok = &Previous;
712     while (Tok && CurrentState.VariablePos >= Tok->ColumnWidth) {
713       CurrentState.VariablePos -= Tok->ColumnWidth;
714       if (Tok->SpacesRequiredBefore != 0)
715         break;
716       Tok = Tok->Previous;
717     }
718     if (Previous.PartOfMultiVariableDeclStmt)
719       CurrentState.LastSpace = CurrentState.VariablePos;
720   }
721 
722   unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
723 
724   // Indent preprocessor directives after the hash if required.
725   int PPColumnCorrection = 0;
726   if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
727       Previous.is(tok::hash) && State.FirstIndent > 0 &&
728       &Previous == State.Line->First &&
729       (State.Line->Type == LT_PreprocessorDirective ||
730        State.Line->Type == LT_ImportStatement)) {
731     Spaces += State.FirstIndent;
732 
733     // For preprocessor indent with tabs, State.Column will be 1 because of the
734     // hash. This causes second-level indents onward to have an extra space
735     // after the tabs. We avoid this misalignment by subtracting 1 from the
736     // column value passed to replaceWhitespace().
737     if (Style.UseTab != FormatStyle::UT_Never)
738       PPColumnCorrection = -1;
739   }
740 
741   if (!DryRun) {
742     Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
743                                   State.Column + Spaces + PPColumnCorrection,
744                                   /*IsAligned=*/false, State.Line->InMacroBody);
745   }
746 
747   // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
748   // declaration unless there is multiple inheritance.
749   if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
750       Current.is(TT_InheritanceColon)) {
751     CurrentState.NoLineBreak = true;
752   }
753   if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
754       Previous.is(TT_InheritanceColon)) {
755     CurrentState.NoLineBreak = true;
756   }
757 
758   if (Current.is(TT_SelectorName) && !CurrentState.ObjCSelectorNameFound) {
759     unsigned MinIndent = std::max(
760         State.FirstIndent + Style.ContinuationIndentWidth, CurrentState.Indent);
761     unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
762     if (Current.LongestObjCSelectorName == 0)
763       CurrentState.AlignColons = false;
764     else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
765       CurrentState.ColonPos = MinIndent + Current.LongestObjCSelectorName;
766     else
767       CurrentState.ColonPos = FirstColonPos;
768   }
769 
770   // In "AlwaysBreak" or "BlockIndent" mode, enforce wrapping directly after the
771   // parenthesis by disallowing any further line breaks if there is no line
772   // break after the opening parenthesis. Don't break if it doesn't conserve
773   // columns.
774   auto IsOpeningBracket = [&](const FormatToken &Tok) {
775     auto IsStartOfBracedList = [&]() {
776       return Tok.is(tok::l_brace) && Tok.isNot(BK_Block) &&
777              Style.Cpp11BracedListStyle;
778     };
779     if (!Tok.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
780         !IsStartOfBracedList()) {
781       return false;
782     }
783     if (!Tok.Previous)
784       return true;
785     if (Tok.Previous->isIf())
786       return Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak;
787     return !Tok.Previous->isOneOf(TT_CastRParen, tok::kw_for, tok::kw_while,
788                                   tok::kw_switch);
789   };
790   if ((Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak ||
791        Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent) &&
792       IsOpeningBracket(Previous) && State.Column > getNewLineColumn(State) &&
793       // Don't do this for simple (no expressions) one-argument function calls
794       // as that feels like needlessly wasting whitespace, e.g.:
795       //
796       //   caaaaaaaaaaaall(
797       //       caaaaaaaaaaaall(
798       //           caaaaaaaaaaaall(
799       //               caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
800       Current.FakeLParens.size() > 0 &&
801       Current.FakeLParens.back() > prec::Unknown) {
802     CurrentState.NoLineBreak = true;
803   }
804   if (Previous.is(TT_TemplateString) && Previous.opensScope())
805     CurrentState.NoLineBreak = true;
806 
807   // Align following lines within parentheses / brackets if configured.
808   // Note: This doesn't apply to macro expansion lines, which are MACRO( , , )
809   // with args as children of the '(' and ',' tokens. It does not make sense to
810   // align the commas with the opening paren.
811   if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
812       !CurrentState.IsCSharpGenericTypeConstraint && Previous.opensScope() &&
813       Previous.isNot(TT_ObjCMethodExpr) && Previous.isNot(TT_RequiresClause) &&
814       !(Current.MacroParent && Previous.MacroParent) &&
815       (Current.isNot(TT_LineComment) ||
816        Previous.isOneOf(BK_BracedInit, TT_VerilogMultiLineListLParen))) {
817     CurrentState.Indent = State.Column + Spaces;
818     CurrentState.IsAligned = true;
819   }
820   if (CurrentState.AvoidBinPacking && startsNextParameter(Current, Style))
821     CurrentState.NoLineBreak = true;
822   if (startsSegmentOfBuilderTypeCall(Current) &&
823       State.Column > getNewLineColumn(State)) {
824     CurrentState.ContainsUnwrappedBuilder = true;
825   }
826 
827   if (Current.is(TT_TrailingReturnArrow) &&
828       Style.Language == FormatStyle::LK_Java) {
829     CurrentState.NoLineBreak = true;
830   }
831   if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
832       (Previous.MatchingParen &&
833        (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10))) {
834     // If there is a function call with long parameters, break before trailing
835     // calls. This prevents things like:
836     //   EXPECT_CALL(SomeLongParameter).Times(
837     //       2);
838     // We don't want to do this for short parameters as they can just be
839     // indexes.
840     CurrentState.NoLineBreak = true;
841   }
842 
843   // Don't allow the RHS of an operator to be split over multiple lines unless
844   // there is a line-break right after the operator.
845   // Exclude relational operators, as there, it is always more desirable to
846   // have the LHS 'left' of the RHS.
847   const FormatToken *P = Current.getPreviousNonComment();
848   if (Current.isNot(tok::comment) && P &&
849       (P->isOneOf(TT_BinaryOperator, tok::comma) ||
850        (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
851       !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
852       P->getPrecedence() != prec::Assignment &&
853       P->getPrecedence() != prec::Relational &&
854       P->getPrecedence() != prec::Spaceship) {
855     bool BreakBeforeOperator =
856         P->MustBreakBefore || P->is(tok::lessless) ||
857         (P->is(TT_BinaryOperator) &&
858          Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
859         (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
860     // Don't do this if there are only two operands. In these cases, there is
861     // always a nice vertical separation between them and the extra line break
862     // does not help.
863     bool HasTwoOperands = P->OperatorIndex == 0 && !P->NextOperator &&
864                           P->isNot(TT_ConditionalExpr);
865     if ((!BreakBeforeOperator &&
866          !(HasTwoOperands &&
867            Style.AlignOperands != FormatStyle::OAS_DontAlign)) ||
868         (!CurrentState.LastOperatorWrapped && BreakBeforeOperator)) {
869       CurrentState.NoLineBreakInOperand = true;
870     }
871   }
872 
873   State.Column += Spaces;
874   if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
875       Previous.Previous &&
876       (Previous.Previous->is(tok::kw_for) || Previous.Previous->isIf())) {
877     // Treat the condition inside an if as if it was a second function
878     // parameter, i.e. let nested calls have a continuation indent.
879     CurrentState.LastSpace = State.Column;
880     CurrentState.NestedBlockIndent = State.Column;
881   } else if (!Current.isOneOf(tok::comment, tok::caret) &&
882              ((Previous.is(tok::comma) &&
883                Previous.isNot(TT_OverloadedOperator)) ||
884               (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
885     CurrentState.LastSpace = State.Column;
886   } else if (Previous.is(TT_CtorInitializerColon) &&
887              (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
888              Style.BreakConstructorInitializers ==
889                  FormatStyle::BCIS_AfterColon) {
890     CurrentState.Indent = State.Column;
891     CurrentState.LastSpace = State.Column;
892   } else if (Previous.isOneOf(TT_ConditionalExpr, TT_CtorInitializerColon)) {
893     CurrentState.LastSpace = State.Column;
894   } else if (Previous.is(TT_BinaryOperator) &&
895              ((Previous.getPrecedence() != prec::Assignment &&
896                (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
897                 Previous.NextOperator)) ||
898               Current.StartsBinaryExpression)) {
899     // Indent relative to the RHS of the expression unless this is a simple
900     // assignment without binary expression on the RHS.
901     if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
902       CurrentState.LastSpace = State.Column;
903   } else if (Previous.is(TT_InheritanceColon)) {
904     CurrentState.Indent = State.Column;
905     CurrentState.LastSpace = State.Column;
906   } else if (Current.is(TT_CSharpGenericTypeConstraintColon)) {
907     CurrentState.ColonPos = State.Column;
908   } else if (Previous.opensScope()) {
909     // If a function has a trailing call, indent all parameters from the
910     // opening parenthesis. This avoids confusing indents like:
911     //   OuterFunction(InnerFunctionCall( // break
912     //       ParameterToInnerFunction))   // break
913     //       .SecondInnerFunctionCall();
914     if (Previous.MatchingParen) {
915       const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
916       if (Next && Next->isMemberAccess() && State.Stack.size() > 1 &&
917           State.Stack[State.Stack.size() - 2].CallContinuation == 0) {
918         CurrentState.LastSpace = State.Column;
919       }
920     }
921   }
922 }
923 
924 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
925                                                  bool DryRun) {
926   FormatToken &Current = *State.NextToken;
927   assert(State.NextToken->Previous);
928   const FormatToken &Previous = *State.NextToken->Previous;
929   auto &CurrentState = State.Stack.back();
930 
931   // Extra penalty that needs to be added because of the way certain line
932   // breaks are chosen.
933   unsigned Penalty = 0;
934 
935   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
936   const FormatToken *NextNonComment = Previous.getNextNonComment();
937   if (!NextNonComment)
938     NextNonComment = &Current;
939   // The first line break on any NestingLevel causes an extra penalty in order
940   // prefer similar line breaks.
941   if (!CurrentState.ContainsLineBreak)
942     Penalty += 15;
943   CurrentState.ContainsLineBreak = true;
944 
945   Penalty += State.NextToken->SplitPenalty;
946 
947   // Breaking before the first "<<" is generally not desirable if the LHS is
948   // short. Also always add the penalty if the LHS is split over multiple lines
949   // to avoid unnecessary line breaks that just work around this penalty.
950   if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess == 0 &&
951       (State.Column <= Style.ColumnLimit / 3 ||
952        CurrentState.BreakBeforeParameter)) {
953     Penalty += Style.PenaltyBreakFirstLessLess;
954   }
955 
956   State.Column = getNewLineColumn(State);
957 
958   // Add Penalty proportional to amount of whitespace away from FirstColumn
959   // This tends to penalize several lines that are far-right indented,
960   // and prefers a line-break prior to such a block, e.g:
961   //
962   // Constructor() :
963   //   member(value), looooooooooooooooong_member(
964   //                      looooooooooong_call(param_1, param_2, param_3))
965   // would then become
966   // Constructor() :
967   //   member(value),
968   //   looooooooooooooooong_member(
969   //       looooooooooong_call(param_1, param_2, param_3))
970   if (State.Column > State.FirstIndent) {
971     Penalty +=
972         Style.PenaltyIndentedWhitespace * (State.Column - State.FirstIndent);
973   }
974 
975   // Indent nested blocks relative to this column, unless in a very specific
976   // JavaScript special case where:
977   //
978   //   var loooooong_name =
979   //       function() {
980   //     // code
981   //   }
982   //
983   // is common and should be formatted like a free-standing function. The same
984   // goes for wrapping before the lambda return type arrow.
985   if (Current.isNot(TT_TrailingReturnArrow) &&
986       (!Style.isJavaScript() || Current.NestingLevel != 0 ||
987        !PreviousNonComment || PreviousNonComment->isNot(tok::equal) ||
988        !Current.isOneOf(Keywords.kw_async, Keywords.kw_function))) {
989     CurrentState.NestedBlockIndent = State.Column;
990   }
991 
992   if (NextNonComment->isMemberAccess()) {
993     if (CurrentState.CallContinuation == 0)
994       CurrentState.CallContinuation = State.Column;
995   } else if (NextNonComment->is(TT_SelectorName)) {
996     if (!CurrentState.ObjCSelectorNameFound) {
997       if (NextNonComment->LongestObjCSelectorName == 0) {
998         CurrentState.AlignColons = false;
999       } else {
1000         CurrentState.ColonPos =
1001             (shouldIndentWrappedSelectorName(Style, State.Line->Type)
1002                  ? std::max(CurrentState.Indent,
1003                             State.FirstIndent + Style.ContinuationIndentWidth)
1004                  : CurrentState.Indent) +
1005             std::max(NextNonComment->LongestObjCSelectorName,
1006                      NextNonComment->ColumnWidth);
1007       }
1008     } else if (CurrentState.AlignColons &&
1009                CurrentState.ColonPos <= NextNonComment->ColumnWidth) {
1010       CurrentState.ColonPos = State.Column + NextNonComment->ColumnWidth;
1011     }
1012   } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1013              PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1014     // FIXME: This is hacky, find a better way. The problem is that in an ObjC
1015     // method expression, the block should be aligned to the line starting it,
1016     // e.g.:
1017     //   [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
1018     //                        ^(int *i) {
1019     //                            // ...
1020     //                        }];
1021     // Thus, we set LastSpace of the next higher NestingLevel, to which we move
1022     // when we consume all of the "}"'s FakeRParens at the "{".
1023     if (State.Stack.size() > 1) {
1024       State.Stack[State.Stack.size() - 2].LastSpace =
1025           std::max(CurrentState.LastSpace, CurrentState.Indent) +
1026           Style.ContinuationIndentWidth;
1027     }
1028   }
1029 
1030   if ((PreviousNonComment &&
1031        PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
1032        !CurrentState.AvoidBinPacking) ||
1033       Previous.is(TT_BinaryOperator)) {
1034     CurrentState.BreakBeforeParameter = false;
1035   }
1036   if (PreviousNonComment &&
1037       (PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) ||
1038        PreviousNonComment->ClosesRequiresClause) &&
1039       Current.NestingLevel == 0) {
1040     CurrentState.BreakBeforeParameter = false;
1041   }
1042   if (NextNonComment->is(tok::question) ||
1043       (PreviousNonComment && PreviousNonComment->is(tok::question))) {
1044     CurrentState.BreakBeforeParameter = true;
1045   }
1046   if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
1047     CurrentState.BreakBeforeParameter = false;
1048 
1049   if (!DryRun) {
1050     unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
1051     if (Current.is(tok::r_brace) && Current.MatchingParen &&
1052         // Only strip trailing empty lines for l_braces that have children, i.e.
1053         // for function expressions (lambdas, arrows, etc).
1054         !Current.MatchingParen->Children.empty()) {
1055       // lambdas and arrow functions are expressions, thus their r_brace is not
1056       // on its own line, and thus not covered by UnwrappedLineFormatter's logic
1057       // about removing empty lines on closing blocks. Special case them here.
1058       MaxEmptyLinesToKeep = 1;
1059     }
1060     unsigned Newlines =
1061         std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
1062     bool ContinuePPDirective =
1063         State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
1064     Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
1065                                   CurrentState.IsAligned, ContinuePPDirective);
1066   }
1067 
1068   if (!Current.isTrailingComment())
1069     CurrentState.LastSpace = State.Column;
1070   if (Current.is(tok::lessless)) {
1071     // If we are breaking before a "<<", we always want to indent relative to
1072     // RHS. This is necessary only for "<<", as we special-case it and don't
1073     // always indent relative to the RHS.
1074     CurrentState.LastSpace += 3; // 3 -> width of "<< ".
1075   }
1076 
1077   State.StartOfLineLevel = Current.NestingLevel;
1078   State.LowestLevelOnLine = Current.NestingLevel;
1079 
1080   // Any break on this level means that the parent level has been broken
1081   // and we need to avoid bin packing there.
1082   bool NestedBlockSpecialCase =
1083       (!Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
1084        State.Stack[State.Stack.size() - 2].NestedBlockInlined) ||
1085       (Style.Language == FormatStyle::LK_ObjC && Current.is(tok::r_brace) &&
1086        State.Stack.size() > 1 && !Style.ObjCBreakBeforeNestedBlockParam);
1087   // Do not force parameter break for statements with requires expressions.
1088   NestedBlockSpecialCase =
1089       NestedBlockSpecialCase ||
1090       (Current.MatchingParen &&
1091        Current.MatchingParen->is(TT_RequiresExpressionLBrace));
1092   if (!NestedBlockSpecialCase) {
1093     auto ParentLevelIt = std::next(State.Stack.rbegin());
1094     if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1095         Current.MatchingParen && Current.MatchingParen->is(TT_LambdaLBrace)) {
1096       // If the first character on the new line is a lambda's closing brace, the
1097       // stack still contains that lambda's parenthesis. As such, we need to
1098       // recurse further down the stack than usual to find the parenthesis level
1099       // containing the lambda, which is where we want to set
1100       // BreakBeforeParameter.
1101       //
1102       // We specifically special case "OuterScope"-formatted lambdas here
1103       // because, when using that setting, breaking before the parameter
1104       // directly following the lambda is particularly unsightly. However, when
1105       // "OuterScope" is not set, the logic to find the parent parenthesis level
1106       // still appears to be sometimes incorrect. It has not been fixed yet
1107       // because it would lead to significant changes in existing behaviour.
1108       //
1109       // TODO: fix the non-"OuterScope" case too.
1110       auto FindCurrentLevel = [&](const auto &It) {
1111         return std::find_if(It, State.Stack.rend(), [](const auto &PState) {
1112           return PState.Tok != nullptr; // Ignore fake parens.
1113         });
1114       };
1115       auto MaybeIncrement = [&](const auto &It) {
1116         return It != State.Stack.rend() ? std::next(It) : It;
1117       };
1118       auto LambdaLevelIt = FindCurrentLevel(State.Stack.rbegin());
1119       auto LevelContainingLambdaIt =
1120           FindCurrentLevel(MaybeIncrement(LambdaLevelIt));
1121       ParentLevelIt = MaybeIncrement(LevelContainingLambdaIt);
1122     }
1123     for (auto I = ParentLevelIt, E = State.Stack.rend(); I != E; ++I)
1124       I->BreakBeforeParameter = true;
1125   }
1126 
1127   if (PreviousNonComment &&
1128       !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
1129       ((PreviousNonComment->isNot(TT_TemplateCloser) &&
1130         !PreviousNonComment->ClosesRequiresClause) ||
1131        Current.NestingLevel != 0) &&
1132       !PreviousNonComment->isOneOf(
1133           TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
1134           TT_LeadingJavaAnnotation) &&
1135       Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope() &&
1136       // We don't want to enforce line breaks for subsequent arguments just
1137       // because we have been forced to break before a lambda body.
1138       (!Style.BraceWrapping.BeforeLambdaBody ||
1139        Current.isNot(TT_LambdaLBrace))) {
1140     CurrentState.BreakBeforeParameter = true;
1141   }
1142 
1143   // If we break after { or the [ of an array initializer, we should also break
1144   // before the corresponding } or ].
1145   if (PreviousNonComment &&
1146       (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1147        opensProtoMessageField(*PreviousNonComment, Style))) {
1148     CurrentState.BreakBeforeClosingBrace = true;
1149   }
1150 
1151   if (PreviousNonComment && PreviousNonComment->is(tok::l_paren)) {
1152     CurrentState.BreakBeforeClosingParen =
1153         Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent;
1154   }
1155 
1156   if (CurrentState.AvoidBinPacking) {
1157     // If we are breaking after '(', '{', '<', or this is the break after a ':'
1158     // to start a member initializer list in a constructor, this should not
1159     // be considered bin packing unless the relevant AllowAll option is false or
1160     // this is a dict/object literal.
1161     bool PreviousIsBreakingCtorInitializerColon =
1162         PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1163         Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
1164     bool AllowAllConstructorInitializersOnNextLine =
1165         Style.PackConstructorInitializers == FormatStyle::PCIS_NextLine ||
1166         Style.PackConstructorInitializers == FormatStyle::PCIS_NextLineOnly;
1167     if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
1168           PreviousIsBreakingCtorInitializerColon) ||
1169         (!Style.AllowAllParametersOfDeclarationOnNextLine &&
1170          State.Line->MustBeDeclaration) ||
1171         (!Style.AllowAllArgumentsOnNextLine &&
1172          !State.Line->MustBeDeclaration) ||
1173         (!AllowAllConstructorInitializersOnNextLine &&
1174          PreviousIsBreakingCtorInitializerColon) ||
1175         Previous.is(TT_DictLiteral)) {
1176       CurrentState.BreakBeforeParameter = true;
1177     }
1178 
1179     // If we are breaking after a ':' to start a member initializer list,
1180     // and we allow all arguments on the next line, we should not break
1181     // before the next parameter.
1182     if (PreviousIsBreakingCtorInitializerColon &&
1183         AllowAllConstructorInitializersOnNextLine) {
1184       CurrentState.BreakBeforeParameter = false;
1185     }
1186   }
1187 
1188   return Penalty;
1189 }
1190 
1191 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
1192   if (!State.NextToken || !State.NextToken->Previous)
1193     return 0;
1194 
1195   FormatToken &Current = *State.NextToken;
1196   const auto &CurrentState = State.Stack.back();
1197 
1198   if (CurrentState.IsCSharpGenericTypeConstraint &&
1199       Current.isNot(TT_CSharpGenericTypeConstraint)) {
1200     return CurrentState.ColonPos + 2;
1201   }
1202 
1203   const FormatToken &Previous = *Current.Previous;
1204   // If we are continuing an expression, we want to use the continuation indent.
1205   unsigned ContinuationIndent =
1206       std::max(CurrentState.LastSpace, CurrentState.Indent) +
1207       Style.ContinuationIndentWidth;
1208   const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
1209   const FormatToken *NextNonComment = Previous.getNextNonComment();
1210   if (!NextNonComment)
1211     NextNonComment = &Current;
1212 
1213   // Java specific bits.
1214   if (Style.Language == FormatStyle::LK_Java &&
1215       Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends)) {
1216     return std::max(CurrentState.LastSpace,
1217                     CurrentState.Indent + Style.ContinuationIndentWidth);
1218   }
1219 
1220   // Indentation of the statement following a Verilog case label is taken care
1221   // of in moveStateToNextToken.
1222   if (Style.isVerilog() && PreviousNonComment &&
1223       Keywords.isVerilogEndOfLabel(*PreviousNonComment)) {
1224     return State.FirstIndent;
1225   }
1226 
1227   if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths &&
1228       State.Line->First->is(tok::kw_enum)) {
1229     return (Style.IndentWidth * State.Line->First->IndentLevel) +
1230            Style.IndentWidth;
1231   }
1232 
1233   if ((NextNonComment->is(tok::l_brace) && NextNonComment->is(BK_Block)) ||
1234       (Style.isVerilog() && Keywords.isVerilogBegin(*NextNonComment))) {
1235     if (Current.NestingLevel == 0 ||
1236         (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1237          State.NextToken->is(TT_LambdaLBrace))) {
1238       return State.FirstIndent;
1239     }
1240     return CurrentState.Indent;
1241   }
1242   if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
1243        (Current.is(tok::greater) && Style.isProto())) &&
1244       State.Stack.size() > 1) {
1245     if (Current.closesBlockOrBlockTypeList(Style))
1246       return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
1247     if (Current.MatchingParen && Current.MatchingParen->is(BK_BracedInit))
1248       return State.Stack[State.Stack.size() - 2].LastSpace;
1249     return State.FirstIndent;
1250   }
1251   // Indent a closing parenthesis at the previous level if followed by a semi,
1252   // const, or opening brace. This allows indentations such as:
1253   //     foo(
1254   //       a,
1255   //     );
1256   //     int Foo::getter(
1257   //         //
1258   //     ) const {
1259   //       return foo;
1260   //     }
1261   //     function foo(
1262   //       a,
1263   //     ) {
1264   //       code(); //
1265   //     }
1266   if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
1267       (!Current.Next ||
1268        Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace))) {
1269     return State.Stack[State.Stack.size() - 2].LastSpace;
1270   }
1271   if (Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent &&
1272       (Current.is(tok::r_paren) ||
1273        (Current.is(tok::r_brace) && Current.MatchingParen &&
1274         Current.MatchingParen->is(BK_BracedInit))) &&
1275       State.Stack.size() > 1) {
1276     return State.Stack[State.Stack.size() - 2].LastSpace;
1277   }
1278   if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
1279     return State.Stack[State.Stack.size() - 2].LastSpace;
1280   // Field labels in a nested type should be aligned to the brace. For example
1281   // in ProtoBuf:
1282   //   optional int32 b = 2 [(foo_options) = {aaaaaaaaaaaaaaaaaaa: 123,
1283   //                                          bbbbbbbbbbbbbbbbbbbbbbbb:"baz"}];
1284   // For Verilog, a quote following a brace is treated as an identifier.  And
1285   // Both braces and colons get annotated as TT_DictLiteral.  So we have to
1286   // check.
1287   if (Current.is(tok::identifier) && Current.Next &&
1288       (!Style.isVerilog() || Current.Next->is(tok::colon)) &&
1289       (Current.Next->is(TT_DictLiteral) ||
1290        (Style.isProto() && Current.Next->isOneOf(tok::less, tok::l_brace)))) {
1291     return CurrentState.Indent;
1292   }
1293   if (NextNonComment->is(TT_ObjCStringLiteral) &&
1294       State.StartOfStringLiteral != 0) {
1295     return State.StartOfStringLiteral - 1;
1296   }
1297   if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
1298     return State.StartOfStringLiteral;
1299   if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess != 0)
1300     return CurrentState.FirstLessLess;
1301   if (NextNonComment->isMemberAccess()) {
1302     if (CurrentState.CallContinuation == 0)
1303       return ContinuationIndent;
1304     return CurrentState.CallContinuation;
1305   }
1306   if (CurrentState.QuestionColumn != 0 &&
1307       ((NextNonComment->is(tok::colon) &&
1308         NextNonComment->is(TT_ConditionalExpr)) ||
1309        Previous.is(TT_ConditionalExpr))) {
1310     if (((NextNonComment->is(tok::colon) && NextNonComment->Next &&
1311           !NextNonComment->Next->FakeLParens.empty() &&
1312           NextNonComment->Next->FakeLParens.back() == prec::Conditional) ||
1313          (Previous.is(tok::colon) && !Current.FakeLParens.empty() &&
1314           Current.FakeLParens.back() == prec::Conditional)) &&
1315         !CurrentState.IsWrappedConditional) {
1316       // NOTE: we may tweak this slightly:
1317       //    * not remove the 'lead' ContinuationIndentWidth
1318       //    * always un-indent by the operator when
1319       //    BreakBeforeTernaryOperators=true
1320       unsigned Indent = CurrentState.Indent;
1321       if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1322         Indent -= Style.ContinuationIndentWidth;
1323       if (Style.BreakBeforeTernaryOperators && CurrentState.UnindentOperator)
1324         Indent -= 2;
1325       return Indent;
1326     }
1327     return CurrentState.QuestionColumn;
1328   }
1329   if (Previous.is(tok::comma) && CurrentState.VariablePos != 0)
1330     return CurrentState.VariablePos;
1331   if (Current.is(TT_RequiresClause)) {
1332     if (Style.IndentRequiresClause)
1333       return CurrentState.Indent + Style.IndentWidth;
1334     switch (Style.RequiresClausePosition) {
1335     case FormatStyle::RCPS_OwnLine:
1336     case FormatStyle::RCPS_WithFollowing:
1337       return CurrentState.Indent;
1338     default:
1339       break;
1340     }
1341   }
1342   if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1343                               TT_InheritanceComma)) {
1344     return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1345   }
1346   if ((PreviousNonComment &&
1347        (PreviousNonComment->ClosesTemplateDeclaration ||
1348         PreviousNonComment->ClosesRequiresClause ||
1349         (PreviousNonComment->is(TT_AttributeMacro) &&
1350          Current.isNot(tok::l_paren)) ||
1351         PreviousNonComment->isOneOf(
1352             TT_AttributeRParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
1353             TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
1354       (!Style.IndentWrappedFunctionNames &&
1355        NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName))) {
1356     return std::max(CurrentState.LastSpace, CurrentState.Indent);
1357   }
1358   if (NextNonComment->is(TT_SelectorName)) {
1359     if (!CurrentState.ObjCSelectorNameFound) {
1360       unsigned MinIndent = CurrentState.Indent;
1361       if (shouldIndentWrappedSelectorName(Style, State.Line->Type)) {
1362         MinIndent = std::max(MinIndent,
1363                              State.FirstIndent + Style.ContinuationIndentWidth);
1364       }
1365       // If LongestObjCSelectorName is 0, we are indenting the first
1366       // part of an ObjC selector (or a selector component which is
1367       // not colon-aligned due to block formatting).
1368       //
1369       // Otherwise, we are indenting a subsequent part of an ObjC
1370       // selector which should be colon-aligned to the longest
1371       // component of the ObjC selector.
1372       //
1373       // In either case, we want to respect Style.IndentWrappedFunctionNames.
1374       return MinIndent +
1375              std::max(NextNonComment->LongestObjCSelectorName,
1376                       NextNonComment->ColumnWidth) -
1377              NextNonComment->ColumnWidth;
1378     }
1379     if (!CurrentState.AlignColons)
1380       return CurrentState.Indent;
1381     if (CurrentState.ColonPos > NextNonComment->ColumnWidth)
1382       return CurrentState.ColonPos - NextNonComment->ColumnWidth;
1383     return CurrentState.Indent;
1384   }
1385   if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1386     return CurrentState.ColonPos;
1387   if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1388     if (CurrentState.StartOfArraySubscripts != 0) {
1389       return CurrentState.StartOfArraySubscripts;
1390     } else if (Style.isCSharp()) { // C# allows `["key"] = value` inside object
1391                                    // initializers.
1392       return CurrentState.Indent;
1393     }
1394     return ContinuationIndent;
1395   }
1396 
1397   // OpenMP clauses want to get additional indentation when they are pushed onto
1398   // the next line.
1399   if (State.Line->InPragmaDirective) {
1400     FormatToken *PragmaType = State.Line->First->Next->Next;
1401     if (PragmaType && PragmaType->TokenText.equals("omp"))
1402       return CurrentState.Indent + Style.ContinuationIndentWidth;
1403   }
1404 
1405   // This ensure that we correctly format ObjC methods calls without inputs,
1406   // i.e. where the last element isn't selector like: [callee method];
1407   if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1408       NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr)) {
1409     return CurrentState.Indent;
1410   }
1411 
1412   if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1413       Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon)) {
1414     return ContinuationIndent;
1415   }
1416   if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1417       PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1418     return ContinuationIndent;
1419   }
1420   if (NextNonComment->is(TT_CtorInitializerComma))
1421     return CurrentState.Indent;
1422   if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1423       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1424     return CurrentState.Indent;
1425   }
1426   if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1427       Style.BreakInheritanceList == FormatStyle::BILS_AfterColon) {
1428     return CurrentState.Indent;
1429   }
1430   if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1431       !Current.isOneOf(tok::colon, tok::comment)) {
1432     return ContinuationIndent;
1433   }
1434   if (Current.is(TT_ProtoExtensionLSquare))
1435     return CurrentState.Indent;
1436   if (Current.isBinaryOperator() && CurrentState.UnindentOperator) {
1437     return CurrentState.Indent - Current.Tok.getLength() -
1438            Current.SpacesRequiredBefore;
1439   }
1440   if (Current.is(tok::comment) && NextNonComment->isBinaryOperator() &&
1441       CurrentState.UnindentOperator) {
1442     return CurrentState.Indent - NextNonComment->Tok.getLength() -
1443            NextNonComment->SpacesRequiredBefore;
1444   }
1445   if (CurrentState.Indent == State.FirstIndent && PreviousNonComment &&
1446       !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma)) {
1447     // Ensure that we fall back to the continuation indent width instead of
1448     // just flushing continuations left.
1449     return CurrentState.Indent + Style.ContinuationIndentWidth;
1450   }
1451   return CurrentState.Indent;
1452 }
1453 
1454 static bool hasNestedBlockInlined(const FormatToken *Previous,
1455                                   const FormatToken &Current,
1456                                   const FormatStyle &Style) {
1457   if (Previous->isNot(tok::l_paren))
1458     return true;
1459   if (Previous->ParameterCount > 1)
1460     return true;
1461 
1462   // Also a nested block if contains a lambda inside function with 1 parameter.
1463   return Style.BraceWrapping.BeforeLambdaBody && Current.is(TT_LambdaLSquare);
1464 }
1465 
1466 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1467                                                     bool DryRun, bool Newline) {
1468   assert(State.Stack.size());
1469   const FormatToken &Current = *State.NextToken;
1470   auto &CurrentState = State.Stack.back();
1471 
1472   if (Current.is(TT_CSharpGenericTypeConstraint))
1473     CurrentState.IsCSharpGenericTypeConstraint = true;
1474   if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1475     CurrentState.NoLineBreakInOperand = false;
1476   if (Current.isOneOf(TT_InheritanceColon, TT_CSharpGenericTypeConstraintColon))
1477     CurrentState.AvoidBinPacking = true;
1478   if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1479     if (CurrentState.FirstLessLess == 0)
1480       CurrentState.FirstLessLess = State.Column;
1481     else
1482       CurrentState.LastOperatorWrapped = Newline;
1483   }
1484   if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1485     CurrentState.LastOperatorWrapped = Newline;
1486   if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1487       Current.Previous->isNot(TT_ConditionalExpr)) {
1488     CurrentState.LastOperatorWrapped = Newline;
1489   }
1490   if (Current.is(TT_ArraySubscriptLSquare) &&
1491       CurrentState.StartOfArraySubscripts == 0) {
1492     CurrentState.StartOfArraySubscripts = State.Column;
1493   }
1494 
1495   auto IsWrappedConditional = [](const FormatToken &Tok) {
1496     if (!(Tok.is(TT_ConditionalExpr) && Tok.is(tok::question)))
1497       return false;
1498     if (Tok.MustBreakBefore)
1499       return true;
1500 
1501     const FormatToken *Next = Tok.getNextNonComment();
1502     return Next && Next->MustBreakBefore;
1503   };
1504   if (IsWrappedConditional(Current))
1505     CurrentState.IsWrappedConditional = true;
1506   if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1507     CurrentState.QuestionColumn = State.Column;
1508   if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1509     const FormatToken *Previous = Current.Previous;
1510     while (Previous && Previous->isTrailingComment())
1511       Previous = Previous->Previous;
1512     if (Previous && Previous->is(tok::question))
1513       CurrentState.QuestionColumn = State.Column;
1514   }
1515   if (!Current.opensScope() && !Current.closesScope() &&
1516       Current.isNot(TT_PointerOrReference)) {
1517     State.LowestLevelOnLine =
1518         std::min(State.LowestLevelOnLine, Current.NestingLevel);
1519   }
1520   if (Current.isMemberAccess())
1521     CurrentState.StartOfFunctionCall = !Current.NextOperator ? 0 : State.Column;
1522   if (Current.is(TT_SelectorName))
1523     CurrentState.ObjCSelectorNameFound = true;
1524   if (Current.is(TT_CtorInitializerColon) &&
1525       Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1526     // Indent 2 from the column, so:
1527     // SomeClass::SomeClass()
1528     //     : First(...), ...
1529     //       Next(...)
1530     //       ^ line up here.
1531     CurrentState.Indent = State.Column + (Style.BreakConstructorInitializers ==
1532                                                   FormatStyle::BCIS_BeforeComma
1533                                               ? 0
1534                                               : 2);
1535     CurrentState.NestedBlockIndent = CurrentState.Indent;
1536     if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack) {
1537       CurrentState.AvoidBinPacking = true;
1538       CurrentState.BreakBeforeParameter =
1539           Style.ColumnLimit > 0 &&
1540           Style.PackConstructorInitializers != FormatStyle::PCIS_NextLine &&
1541           Style.PackConstructorInitializers != FormatStyle::PCIS_NextLineOnly;
1542     } else {
1543       CurrentState.BreakBeforeParameter = false;
1544     }
1545   }
1546   if (Current.is(TT_CtorInitializerColon) &&
1547       Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1548     CurrentState.Indent =
1549         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1550     CurrentState.NestedBlockIndent = CurrentState.Indent;
1551     if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack)
1552       CurrentState.AvoidBinPacking = true;
1553     else
1554       CurrentState.BreakBeforeParameter = false;
1555   }
1556   if (Current.is(TT_InheritanceColon)) {
1557     CurrentState.Indent =
1558         State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1559   }
1560   if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1561     CurrentState.NestedBlockIndent = State.Column + Current.ColumnWidth + 1;
1562   if (Current.isOneOf(TT_LambdaLSquare, TT_TrailingReturnArrow))
1563     CurrentState.LastSpace = State.Column;
1564   if (Current.is(TT_RequiresExpression) &&
1565       Style.RequiresExpressionIndentation == FormatStyle::REI_Keyword) {
1566     CurrentState.NestedBlockIndent = State.Column;
1567   }
1568 
1569   // Insert scopes created by fake parenthesis.
1570   const FormatToken *Previous = Current.getPreviousNonComment();
1571 
1572   // Add special behavior to support a format commonly used for JavaScript
1573   // closures:
1574   //   SomeFunction(function() {
1575   //     foo();
1576   //     bar();
1577   //   }, a, b, c);
1578   if (Current.isNot(tok::comment) && !Current.ClosesRequiresClause &&
1579       Previous && Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1580       Previous->isNot(TT_DictLiteral) && State.Stack.size() > 1 &&
1581       !CurrentState.HasMultipleNestedBlocks) {
1582     if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1583       for (ParenState &PState : llvm::drop_end(State.Stack))
1584         PState.NoLineBreak = true;
1585     State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1586   }
1587   if (Previous && (Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr) ||
1588                    (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) &&
1589                     !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)))) {
1590     CurrentState.NestedBlockInlined =
1591         !Newline && hasNestedBlockInlined(Previous, Current, Style);
1592   }
1593 
1594   moveStatePastFakeLParens(State, Newline);
1595   moveStatePastScopeCloser(State);
1596   // Do not use CurrentState here, since the two functions before may change the
1597   // Stack.
1598   bool AllowBreak = !State.Stack.back().NoLineBreak &&
1599                     !State.Stack.back().NoLineBreakInOperand;
1600   moveStatePastScopeOpener(State, Newline);
1601   moveStatePastFakeRParens(State);
1602 
1603   if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1604     State.StartOfStringLiteral = State.Column + 1;
1605   if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0) {
1606     State.StartOfStringLiteral = State.Column + 1;
1607   } else if (Current.is(TT_TableGenMultiLineString) &&
1608              State.StartOfStringLiteral == 0) {
1609     State.StartOfStringLiteral = State.Column + 1;
1610   } else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0) {
1611     State.StartOfStringLiteral = State.Column;
1612   } else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1613              !Current.isStringLiteral()) {
1614     State.StartOfStringLiteral = 0;
1615   }
1616 
1617   State.Column += Current.ColumnWidth;
1618   State.NextToken = State.NextToken->Next;
1619   // Verilog case labels are on the same unwrapped lines as the statements that
1620   // follow. TokenAnnotator identifies them and sets MustBreakBefore.
1621   // Indentation is taken care of here. A case label can only have 1 statement
1622   // in Verilog, so we don't have to worry about lines that follow.
1623   if (Style.isVerilog() && State.NextToken &&
1624       State.NextToken->MustBreakBefore &&
1625       Keywords.isVerilogEndOfLabel(Current)) {
1626     State.FirstIndent += Style.IndentWidth;
1627     CurrentState.Indent = State.FirstIndent;
1628   }
1629 
1630   unsigned Penalty =
1631       handleEndOfLine(Current, State, DryRun, AllowBreak, Newline);
1632 
1633   if (Current.Role)
1634     Current.Role->formatFromToken(State, this, DryRun);
1635   // If the previous has a special role, let it consume tokens as appropriate.
1636   // It is necessary to start at the previous token for the only implemented
1637   // role (comma separated list). That way, the decision whether or not to break
1638   // after the "{" is already done and both options are tried and evaluated.
1639   // FIXME: This is ugly, find a better way.
1640   if (Previous && Previous->Role)
1641     Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1642 
1643   return Penalty;
1644 }
1645 
1646 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1647                                                     bool Newline) {
1648   const FormatToken &Current = *State.NextToken;
1649   if (Current.FakeLParens.empty())
1650     return;
1651 
1652   const FormatToken *Previous = Current.getPreviousNonComment();
1653 
1654   // Don't add extra indentation for the first fake parenthesis after
1655   // 'return', assignments, opening <({[, or requires clauses. The indentation
1656   // for these cases is special cased.
1657   bool SkipFirstExtraIndent =
1658       Previous &&
1659       (Previous->opensScope() ||
1660        Previous->isOneOf(tok::semi, tok::kw_return, TT_RequiresClause) ||
1661        (Previous->getPrecedence() == prec::Assignment &&
1662         Style.AlignOperands != FormatStyle::OAS_DontAlign) ||
1663        Previous->is(TT_ObjCMethodExpr));
1664   for (const auto &PrecedenceLevel : llvm::reverse(Current.FakeLParens)) {
1665     const auto &CurrentState = State.Stack.back();
1666     ParenState NewParenState = CurrentState;
1667     NewParenState.Tok = nullptr;
1668     NewParenState.ContainsLineBreak = false;
1669     NewParenState.LastOperatorWrapped = true;
1670     NewParenState.IsChainedConditional = false;
1671     NewParenState.IsWrappedConditional = false;
1672     NewParenState.UnindentOperator = false;
1673     NewParenState.NoLineBreak =
1674         NewParenState.NoLineBreak || CurrentState.NoLineBreakInOperand;
1675 
1676     // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1677     if (PrecedenceLevel > prec::Comma)
1678       NewParenState.AvoidBinPacking = false;
1679 
1680     // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1681     // a builder type call after 'return' or, if the alignment after opening
1682     // brackets is disabled.
1683     if (!Current.isTrailingComment() &&
1684         (Style.AlignOperands != FormatStyle::OAS_DontAlign ||
1685          PrecedenceLevel < prec::Assignment) &&
1686         (!Previous || Previous->isNot(tok::kw_return) ||
1687          (Style.Language != FormatStyle::LK_Java && PrecedenceLevel > 0)) &&
1688         (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1689          PrecedenceLevel != prec::Comma || Current.NestingLevel == 0)) {
1690       NewParenState.Indent = std::max(
1691           std::max(State.Column, NewParenState.Indent), CurrentState.LastSpace);
1692     }
1693 
1694     // Special case for generic selection expressions, its comma-separated
1695     // expressions are not aligned to the opening paren like regular calls, but
1696     // rather continuation-indented relative to the _Generic keyword.
1697     if (Previous && Previous->endsSequence(tok::l_paren, tok::kw__Generic))
1698       NewParenState.Indent = CurrentState.LastSpace;
1699 
1700     if ((shouldUnindentNextOperator(Current) ||
1701          (Previous &&
1702           (PrecedenceLevel == prec::Conditional &&
1703            Previous->is(tok::question) && Previous->is(TT_ConditionalExpr)))) &&
1704         !Newline) {
1705       // If BreakBeforeBinaryOperators is set, un-indent a bit to account for
1706       // the operator and keep the operands aligned.
1707       if (Style.AlignOperands == FormatStyle::OAS_AlignAfterOperator)
1708         NewParenState.UnindentOperator = true;
1709       // Mark indentation as alignment if the expression is aligned.
1710       if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1711         NewParenState.IsAligned = true;
1712     }
1713 
1714     // Do not indent relative to the fake parentheses inserted for "." or "->".
1715     // This is a special case to make the following to statements consistent:
1716     //   OuterFunction(InnerFunctionCall( // break
1717     //       ParameterToInnerFunction));
1718     //   OuterFunction(SomeObject.InnerFunctionCall( // break
1719     //       ParameterToInnerFunction));
1720     if (PrecedenceLevel > prec::Unknown)
1721       NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1722     if (PrecedenceLevel != prec::Conditional &&
1723         Current.isNot(TT_UnaryOperator) &&
1724         Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign) {
1725       NewParenState.StartOfFunctionCall = State.Column;
1726     }
1727 
1728     // Indent conditional expressions, unless they are chained "else-if"
1729     // conditionals. Never indent expression where the 'operator' is ',', ';' or
1730     // an assignment (i.e. *I <= prec::Assignment) as those have different
1731     // indentation rules. Indent other expression, unless the indentation needs
1732     // to be skipped.
1733     if (PrecedenceLevel == prec::Conditional && Previous &&
1734         Previous->is(tok::colon) && Previous->is(TT_ConditionalExpr) &&
1735         &PrecedenceLevel == &Current.FakeLParens.back() &&
1736         !CurrentState.IsWrappedConditional) {
1737       NewParenState.IsChainedConditional = true;
1738       NewParenState.UnindentOperator = State.Stack.back().UnindentOperator;
1739     } else if (PrecedenceLevel == prec::Conditional ||
1740                (!SkipFirstExtraIndent && PrecedenceLevel > prec::Assignment &&
1741                 !Current.isTrailingComment())) {
1742       NewParenState.Indent += Style.ContinuationIndentWidth;
1743     }
1744     if ((Previous && !Previous->opensScope()) || PrecedenceLevel != prec::Comma)
1745       NewParenState.BreakBeforeParameter = false;
1746     State.Stack.push_back(NewParenState);
1747     SkipFirstExtraIndent = false;
1748   }
1749 }
1750 
1751 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1752   for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1753     unsigned VariablePos = State.Stack.back().VariablePos;
1754     if (State.Stack.size() == 1) {
1755       // Do not pop the last element.
1756       break;
1757     }
1758     State.Stack.pop_back();
1759     State.Stack.back().VariablePos = VariablePos;
1760   }
1761 
1762   if (State.NextToken->ClosesRequiresClause && Style.IndentRequiresClause) {
1763     // Remove the indentation of the requires clauses (which is not in Indent,
1764     // but in LastSpace).
1765     State.Stack.back().LastSpace -= Style.IndentWidth;
1766   }
1767 }
1768 
1769 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1770                                                     bool Newline) {
1771   const FormatToken &Current = *State.NextToken;
1772   if (!Current.opensScope())
1773     return;
1774 
1775   const auto &CurrentState = State.Stack.back();
1776 
1777   // Don't allow '<' or '(' in C# generic type constraints to start new scopes.
1778   if (Current.isOneOf(tok::less, tok::l_paren) &&
1779       CurrentState.IsCSharpGenericTypeConstraint) {
1780     return;
1781   }
1782 
1783   if (Current.MatchingParen && Current.is(BK_Block)) {
1784     moveStateToNewBlock(State);
1785     return;
1786   }
1787 
1788   unsigned NewIndent;
1789   unsigned LastSpace = CurrentState.LastSpace;
1790   bool AvoidBinPacking;
1791   bool BreakBeforeParameter = false;
1792   unsigned NestedBlockIndent = std::max(CurrentState.StartOfFunctionCall,
1793                                         CurrentState.NestedBlockIndent);
1794   if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1795       opensProtoMessageField(Current, Style)) {
1796     if (Current.opensBlockOrBlockTypeList(Style)) {
1797       NewIndent = Style.IndentWidth +
1798                   std::min(State.Column, CurrentState.NestedBlockIndent);
1799     } else if (Current.is(tok::l_brace)) {
1800       NewIndent =
1801           CurrentState.LastSpace + Style.BracedInitializerIndentWidth.value_or(
1802                                        Style.ContinuationIndentWidth);
1803     } else {
1804       NewIndent = CurrentState.LastSpace + Style.ContinuationIndentWidth;
1805     }
1806     const FormatToken *NextNonComment = Current.getNextNonComment();
1807     bool EndsInComma = Current.MatchingParen &&
1808                        Current.MatchingParen->Previous &&
1809                        Current.MatchingParen->Previous->is(tok::comma);
1810     AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1811                       Style.isProto() || !Style.BinPackArguments ||
1812                       (NextNonComment && NextNonComment->isOneOf(
1813                                              TT_DesignatedInitializerPeriod,
1814                                              TT_DesignatedInitializerLSquare));
1815     BreakBeforeParameter = EndsInComma;
1816     if (Current.ParameterCount > 1)
1817       NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1818   } else {
1819     NewIndent =
1820         Style.ContinuationIndentWidth +
1821         std::max(CurrentState.LastSpace, CurrentState.StartOfFunctionCall);
1822 
1823     // Ensure that different different brackets force relative alignment, e.g.:
1824     // void SomeFunction(vector<  // break
1825     //                       int> v);
1826     // FIXME: We likely want to do this for more combinations of brackets.
1827     if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1828       NewIndent = std::max(NewIndent, CurrentState.Indent);
1829       LastSpace = std::max(LastSpace, CurrentState.Indent);
1830     }
1831 
1832     bool EndsInComma =
1833         Current.MatchingParen &&
1834         Current.MatchingParen->getPreviousNonComment() &&
1835         Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1836 
1837     // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1838     // for backwards compatibility.
1839     bool ObjCBinPackProtocolList =
1840         (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1841          Style.BinPackParameters) ||
1842         Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1843 
1844     bool BinPackDeclaration =
1845         (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1846         (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1847 
1848     bool GenericSelection =
1849         Current.getPreviousNonComment() &&
1850         Current.getPreviousNonComment()->is(tok::kw__Generic);
1851 
1852     AvoidBinPacking =
1853         (CurrentState.IsCSharpGenericTypeConstraint) || GenericSelection ||
1854         (Style.isJavaScript() && EndsInComma) ||
1855         (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1856         (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1857         (Style.ExperimentalAutoDetectBinPacking &&
1858          (Current.is(PPK_OnePerLine) ||
1859           (!BinPackInconclusiveFunctions && Current.is(PPK_Inconclusive))));
1860 
1861     if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen &&
1862         Style.ObjCBreakBeforeNestedBlockParam) {
1863       if (Style.ColumnLimit) {
1864         // If this '[' opens an ObjC call, determine whether all parameters fit
1865         // into one line and put one per line if they don't.
1866         if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1867             getColumnLimit(State)) {
1868           BreakBeforeParameter = true;
1869         }
1870       } else {
1871         // For ColumnLimit = 0, we have to figure out whether there is or has to
1872         // be a line break within this call.
1873         for (const FormatToken *Tok = &Current;
1874              Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1875           if (Tok->MustBreakBefore ||
1876               (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1877             BreakBeforeParameter = true;
1878             break;
1879           }
1880         }
1881       }
1882     }
1883 
1884     if (Style.isJavaScript() && EndsInComma)
1885       BreakBeforeParameter = true;
1886   }
1887   // Generally inherit NoLineBreak from the current scope to nested scope.
1888   // However, don't do this for non-empty nested blocks, dict literals and
1889   // array literals as these follow different indentation rules.
1890   bool NoLineBreak =
1891       Current.Children.empty() &&
1892       !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1893       (CurrentState.NoLineBreak || CurrentState.NoLineBreakInOperand ||
1894        (Current.is(TT_TemplateOpener) &&
1895         CurrentState.ContainsUnwrappedBuilder));
1896   State.Stack.push_back(
1897       ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1898   auto &NewState = State.Stack.back();
1899   NewState.NestedBlockIndent = NestedBlockIndent;
1900   NewState.BreakBeforeParameter = BreakBeforeParameter;
1901   NewState.HasMultipleNestedBlocks = (Current.BlockParameterCount > 1);
1902 
1903   if (Style.BraceWrapping.BeforeLambdaBody && Current.Next &&
1904       Current.is(tok::l_paren)) {
1905     // Search for any parameter that is a lambda.
1906     FormatToken const *next = Current.Next;
1907     while (next) {
1908       if (next->is(TT_LambdaLSquare)) {
1909         NewState.HasMultipleNestedBlocks = true;
1910         break;
1911       }
1912       next = next->Next;
1913     }
1914   }
1915 
1916   NewState.IsInsideObjCArrayLiteral = Current.is(TT_ArrayInitializerLSquare) &&
1917                                       Current.Previous &&
1918                                       Current.Previous->is(tok::at);
1919 }
1920 
1921 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1922   const FormatToken &Current = *State.NextToken;
1923   if (!Current.closesScope())
1924     return;
1925 
1926   // If we encounter a closing ), ], } or >, we can remove a level from our
1927   // stacks.
1928   if (State.Stack.size() > 1 &&
1929       (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1930        (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1931        State.NextToken->is(TT_TemplateCloser) ||
1932        (Current.is(tok::greater) && Current.is(TT_DictLiteral)))) {
1933     State.Stack.pop_back();
1934   }
1935 
1936   auto &CurrentState = State.Stack.back();
1937 
1938   // Reevaluate whether ObjC message arguments fit into one line.
1939   // If a receiver spans multiple lines, e.g.:
1940   //   [[object block:^{
1941   //     return 42;
1942   //   }] a:42 b:42];
1943   // BreakBeforeParameter is calculated based on an incorrect assumption
1944   // (it is checked whether the whole expression fits into one line without
1945   // considering a line break inside a message receiver).
1946   // We check whether arguments fit after receiver scope closer (into the same
1947   // line).
1948   if (CurrentState.BreakBeforeParameter && Current.MatchingParen &&
1949       Current.MatchingParen->Previous) {
1950     const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1951     if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1952         CurrentScopeOpener.MatchingParen) {
1953       int NecessarySpaceInLine =
1954           getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1955           CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1956       if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1957           Style.ColumnLimit) {
1958         CurrentState.BreakBeforeParameter = false;
1959       }
1960     }
1961   }
1962 
1963   if (Current.is(tok::r_square)) {
1964     // If this ends the array subscript expr, reset the corresponding value.
1965     const FormatToken *NextNonComment = Current.getNextNonComment();
1966     if (NextNonComment && NextNonComment->isNot(tok::l_square))
1967       CurrentState.StartOfArraySubscripts = 0;
1968   }
1969 }
1970 
1971 void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1972   if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1973       State.NextToken->is(TT_LambdaLBrace) &&
1974       !State.Line->MightBeFunctionDecl) {
1975     State.Stack.back().NestedBlockIndent = State.FirstIndent;
1976   }
1977   unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1978   // ObjC block sometimes follow special indentation rules.
1979   unsigned NewIndent =
1980       NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1981                                ? Style.ObjCBlockIndentWidth
1982                                : Style.IndentWidth);
1983   State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1984                                    State.Stack.back().LastSpace,
1985                                    /*AvoidBinPacking=*/true,
1986                                    /*NoLineBreak=*/false));
1987   State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1988   State.Stack.back().BreakBeforeParameter = true;
1989 }
1990 
1991 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1992                                      unsigned TabWidth,
1993                                      encoding::Encoding Encoding) {
1994   size_t LastNewlinePos = Text.find_last_of("\n");
1995   if (LastNewlinePos == StringRef::npos) {
1996     return StartColumn +
1997            encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
1998   } else {
1999     return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
2000                                          /*StartColumn=*/0, TabWidth, Encoding);
2001   }
2002 }
2003 
2004 unsigned ContinuationIndenter::reformatRawStringLiteral(
2005     const FormatToken &Current, LineState &State,
2006     const FormatStyle &RawStringStyle, bool DryRun, bool Newline) {
2007   unsigned StartColumn = State.Column - Current.ColumnWidth;
2008   StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
2009   StringRef NewDelimiter =
2010       getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
2011   if (NewDelimiter.empty())
2012     NewDelimiter = OldDelimiter;
2013   // The text of a raw string is between the leading 'R"delimiter(' and the
2014   // trailing 'delimiter)"'.
2015   unsigned OldPrefixSize = 3 + OldDelimiter.size();
2016   unsigned OldSuffixSize = 2 + OldDelimiter.size();
2017   // We create a virtual text environment which expects a null-terminated
2018   // string, so we cannot use StringRef.
2019   std::string RawText = std::string(
2020       Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize));
2021   if (NewDelimiter != OldDelimiter) {
2022     // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
2023     // raw string.
2024     std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
2025     if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
2026       NewDelimiter = OldDelimiter;
2027   }
2028 
2029   unsigned NewPrefixSize = 3 + NewDelimiter.size();
2030   unsigned NewSuffixSize = 2 + NewDelimiter.size();
2031 
2032   // The first start column is the column the raw text starts after formatting.
2033   unsigned FirstStartColumn = StartColumn + NewPrefixSize;
2034 
2035   // The next start column is the intended indentation a line break inside
2036   // the raw string at level 0. It is determined by the following rules:
2037   //   - if the content starts on newline, it is one level more than the current
2038   //     indent, and
2039   //   - if the content does not start on a newline, it is the first start
2040   //     column.
2041   // These rules have the advantage that the formatted content both does not
2042   // violate the rectangle rule and visually flows within the surrounding
2043   // source.
2044   bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
2045   // If this token is the last parameter (checked by looking if it's followed by
2046   // `)` and is not on a newline, the base the indent off the line's nested
2047   // block indent. Otherwise, base the indent off the arguments indent, so we
2048   // can achieve:
2049   //
2050   // fffffffffff(1, 2, 3, R"pb(
2051   //     key1: 1  #
2052   //     key2: 2)pb");
2053   //
2054   // fffffffffff(1, 2, 3,
2055   //             R"pb(
2056   //               key1: 1  #
2057   //               key2: 2
2058   //             )pb");
2059   //
2060   // fffffffffff(1, 2, 3,
2061   //             R"pb(
2062   //               key1: 1  #
2063   //               key2: 2
2064   //             )pb",
2065   //             5);
2066   unsigned CurrentIndent =
2067       (!Newline && Current.Next && Current.Next->is(tok::r_paren))
2068           ? State.Stack.back().NestedBlockIndent
2069           : State.Stack.back().Indent;
2070   unsigned NextStartColumn = ContentStartsOnNewline
2071                                  ? CurrentIndent + Style.IndentWidth
2072                                  : FirstStartColumn;
2073 
2074   // The last start column is the column the raw string suffix starts if it is
2075   // put on a newline.
2076   // The last start column is the intended indentation of the raw string postfix
2077   // if it is put on a newline. It is determined by the following rules:
2078   //   - if the raw string prefix starts on a newline, it is the column where
2079   //     that raw string prefix starts, and
2080   //   - if the raw string prefix does not start on a newline, it is the current
2081   //     indent.
2082   unsigned LastStartColumn =
2083       Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent;
2084 
2085   std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
2086       RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
2087       FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
2088       /*Status=*/nullptr);
2089 
2090   auto NewCode = applyAllReplacements(RawText, Fixes.first);
2091   tooling::Replacements NoFixes;
2092   if (!NewCode)
2093     return addMultilineToken(Current, State);
2094   if (!DryRun) {
2095     if (NewDelimiter != OldDelimiter) {
2096       // In 'R"delimiter(...', the delimiter starts 2 characters after the start
2097       // of the token.
2098       SourceLocation PrefixDelimiterStart =
2099           Current.Tok.getLocation().getLocWithOffset(2);
2100       auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
2101           SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2102       if (PrefixErr) {
2103         llvm::errs()
2104             << "Failed to update the prefix delimiter of a raw string: "
2105             << llvm::toString(std::move(PrefixErr)) << "\n";
2106       }
2107       // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
2108       // position length - 1 - |delimiter|.
2109       SourceLocation SuffixDelimiterStart =
2110           Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
2111                                                      1 - OldDelimiter.size());
2112       auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
2113           SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2114       if (SuffixErr) {
2115         llvm::errs()
2116             << "Failed to update the suffix delimiter of a raw string: "
2117             << llvm::toString(std::move(SuffixErr)) << "\n";
2118       }
2119     }
2120     SourceLocation OriginLoc =
2121         Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
2122     for (const tooling::Replacement &Fix : Fixes.first) {
2123       auto Err = Whitespaces.addReplacement(tooling::Replacement(
2124           SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
2125           Fix.getLength(), Fix.getReplacementText()));
2126       if (Err) {
2127         llvm::errs() << "Failed to reformat raw string: "
2128                      << llvm::toString(std::move(Err)) << "\n";
2129       }
2130     }
2131   }
2132   unsigned RawLastLineEndColumn = getLastLineEndColumn(
2133       *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
2134   State.Column = RawLastLineEndColumn + NewSuffixSize;
2135   // Since we're updating the column to after the raw string literal here, we
2136   // have to manually add the penalty for the prefix R"delim( over the column
2137   // limit.
2138   unsigned PrefixExcessCharacters =
2139       StartColumn + NewPrefixSize > Style.ColumnLimit
2140           ? StartColumn + NewPrefixSize - Style.ColumnLimit
2141           : 0;
2142   bool IsMultiline =
2143       ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos);
2144   if (IsMultiline) {
2145     // Break before further function parameters on all levels.
2146     for (ParenState &Paren : State.Stack)
2147       Paren.BreakBeforeParameter = true;
2148   }
2149   return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
2150 }
2151 
2152 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
2153                                                  LineState &State) {
2154   // Break before further function parameters on all levels.
2155   for (ParenState &Paren : State.Stack)
2156     Paren.BreakBeforeParameter = true;
2157 
2158   unsigned ColumnsUsed = State.Column;
2159   // We can only affect layout of the first and the last line, so the penalty
2160   // for all other lines is constant, and we ignore it.
2161   State.Column = Current.LastLineColumnWidth;
2162 
2163   if (ColumnsUsed > getColumnLimit(State))
2164     return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
2165   return 0;
2166 }
2167 
2168 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
2169                                                LineState &State, bool DryRun,
2170                                                bool AllowBreak, bool Newline) {
2171   unsigned Penalty = 0;
2172   // Compute the raw string style to use in case this is a raw string literal
2173   // that can be reformatted.
2174   auto RawStringStyle = getRawStringStyle(Current, State);
2175   if (RawStringStyle && !Current.Finalized) {
2176     Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun,
2177                                        Newline);
2178   } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
2179     // Don't break multi-line tokens other than block comments and raw string
2180     // literals. Instead, just update the state.
2181     Penalty = addMultilineToken(Current, State);
2182   } else if (State.Line->Type != LT_ImportStatement) {
2183     // We generally don't break import statements.
2184     LineState OriginalState = State;
2185 
2186     // Whether we force the reflowing algorithm to stay strictly within the
2187     // column limit.
2188     bool Strict = false;
2189     // Whether the first non-strict attempt at reflowing did intentionally
2190     // exceed the column limit.
2191     bool Exceeded = false;
2192     std::tie(Penalty, Exceeded) = breakProtrudingToken(
2193         Current, State, AllowBreak, /*DryRun=*/true, Strict);
2194     if (Exceeded) {
2195       // If non-strict reflowing exceeds the column limit, try whether strict
2196       // reflowing leads to an overall lower penalty.
2197       LineState StrictState = OriginalState;
2198       unsigned StrictPenalty =
2199           breakProtrudingToken(Current, StrictState, AllowBreak,
2200                                /*DryRun=*/true, /*Strict=*/true)
2201               .first;
2202       Strict = StrictPenalty <= Penalty;
2203       if (Strict) {
2204         Penalty = StrictPenalty;
2205         State = StrictState;
2206       }
2207     }
2208     if (!DryRun) {
2209       // If we're not in dry-run mode, apply the changes with the decision on
2210       // strictness made above.
2211       breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
2212                            Strict);
2213     }
2214   }
2215   if (State.Column > getColumnLimit(State)) {
2216     unsigned ExcessCharacters = State.Column - getColumnLimit(State);
2217     Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
2218   }
2219   return Penalty;
2220 }
2221 
2222 // Returns the enclosing function name of a token, or the empty string if not
2223 // found.
2224 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
2225   // Look for: 'function(' or 'function<templates>(' before Current.
2226   auto Tok = Current.getPreviousNonComment();
2227   if (!Tok || Tok->isNot(tok::l_paren))
2228     return "";
2229   Tok = Tok->getPreviousNonComment();
2230   if (!Tok)
2231     return "";
2232   if (Tok->is(TT_TemplateCloser)) {
2233     Tok = Tok->MatchingParen;
2234     if (Tok)
2235       Tok = Tok->getPreviousNonComment();
2236   }
2237   if (!Tok || Tok->isNot(tok::identifier))
2238     return "";
2239   return Tok->TokenText;
2240 }
2241 
2242 std::optional<FormatStyle>
2243 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
2244                                         const LineState &State) {
2245   if (!Current.isStringLiteral())
2246     return std::nullopt;
2247   auto Delimiter = getRawStringDelimiter(Current.TokenText);
2248   if (!Delimiter)
2249     return std::nullopt;
2250   auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
2251   if (!RawStringStyle && Delimiter->empty()) {
2252     RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
2253         getEnclosingFunctionName(Current));
2254   }
2255   if (!RawStringStyle)
2256     return std::nullopt;
2257   RawStringStyle->ColumnLimit = getColumnLimit(State);
2258   return RawStringStyle;
2259 }
2260 
2261 std::unique_ptr<BreakableToken>
2262 ContinuationIndenter::createBreakableToken(const FormatToken &Current,
2263                                            LineState &State, bool AllowBreak) {
2264   unsigned StartColumn = State.Column - Current.ColumnWidth;
2265   if (Current.isStringLiteral()) {
2266     // Strings in JSON cannot be broken. Breaking strings in JavaScript is
2267     // disabled for now.
2268     if (Style.isJson() || Style.isJavaScript() || !Style.BreakStringLiterals ||
2269         !AllowBreak) {
2270       return nullptr;
2271     }
2272 
2273     // Don't break string literals inside preprocessor directives (except for
2274     // #define directives, as their contents are stored in separate lines and
2275     // are not affected by this check).
2276     // This way we avoid breaking code with line directives and unknown
2277     // preprocessor directives that contain long string literals.
2278     if (State.Line->Type == LT_PreprocessorDirective)
2279       return nullptr;
2280     // Exempts unterminated string literals from line breaking. The user will
2281     // likely want to terminate the string before any line breaking is done.
2282     if (Current.IsUnterminatedLiteral)
2283       return nullptr;
2284     // Don't break string literals inside Objective-C array literals (doing so
2285     // raises the warning -Wobjc-string-concatenation).
2286     if (State.Stack.back().IsInsideObjCArrayLiteral)
2287       return nullptr;
2288 
2289     // The "DPI"/"DPI-C" in SystemVerilog direct programming interface
2290     // imports/exports cannot be split, e.g.
2291     // `import "DPI" function foo();`
2292     // FIXME: make this use same infra as C++ import checks
2293     if (Style.isVerilog() && Current.Previous &&
2294         Current.Previous->isOneOf(tok::kw_export, Keywords.kw_import)) {
2295       return nullptr;
2296     }
2297     StringRef Text = Current.TokenText;
2298 
2299     // We need this to address the case where there is an unbreakable tail only
2300     // if certain other formatting decisions have been taken. The
2301     // UnbreakableTailLength of Current is an overapproximation in that case and
2302     // we need to be correct here.
2303     unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
2304                                          ? 0
2305                                          : Current.UnbreakableTailLength;
2306 
2307     if (Style.isVerilog() || Style.Language == FormatStyle::LK_Java ||
2308         Style.isJavaScript() || Style.isCSharp()) {
2309       BreakableStringLiteralUsingOperators::QuoteStyleType QuoteStyle;
2310       if (Style.isJavaScript() && Text.starts_with("'") &&
2311           Text.ends_with("'")) {
2312         QuoteStyle = BreakableStringLiteralUsingOperators::SingleQuotes;
2313       } else if (Style.isCSharp() && Text.starts_with("@\"") &&
2314                  Text.ends_with("\"")) {
2315         QuoteStyle = BreakableStringLiteralUsingOperators::AtDoubleQuotes;
2316       } else if (Text.starts_with("\"") && Text.ends_with("\"")) {
2317         QuoteStyle = BreakableStringLiteralUsingOperators::DoubleQuotes;
2318       } else {
2319         return nullptr;
2320       }
2321       return std::make_unique<BreakableStringLiteralUsingOperators>(
2322           Current, QuoteStyle,
2323           /*UnindentPlus=*/shouldUnindentNextOperator(Current), StartColumn,
2324           UnbreakableTailLength, State.Line->InPPDirective, Encoding, Style);
2325     }
2326 
2327     StringRef Prefix;
2328     StringRef Postfix;
2329     // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
2330     // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
2331     // reduce the overhead) for each FormatToken, which is a string, so that we
2332     // don't run multiple checks here on the hot path.
2333     if ((Text.ends_with(Postfix = "\"") &&
2334          (Text.starts_with(Prefix = "@\"") || Text.starts_with(Prefix = "\"") ||
2335           Text.starts_with(Prefix = "u\"") ||
2336           Text.starts_with(Prefix = "U\"") ||
2337           Text.starts_with(Prefix = "u8\"") ||
2338           Text.starts_with(Prefix = "L\""))) ||
2339         (Text.starts_with(Prefix = "_T(\"") &&
2340          Text.ends_with(Postfix = "\")"))) {
2341       return std::make_unique<BreakableStringLiteral>(
2342           Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
2343           State.Line->InPPDirective, Encoding, Style);
2344     }
2345   } else if (Current.is(TT_BlockComment)) {
2346     if (!Style.ReflowComments ||
2347         // If a comment token switches formatting, like
2348         // /* clang-format on */, we don't want to break it further,
2349         // but we may still want to adjust its indentation.
2350         switchesFormatting(Current)) {
2351       return nullptr;
2352     }
2353     return std::make_unique<BreakableBlockComment>(
2354         Current, StartColumn, Current.OriginalColumn, !Current.Previous,
2355         State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF());
2356   } else if (Current.is(TT_LineComment) &&
2357              (!Current.Previous ||
2358               Current.Previous->isNot(TT_ImplicitStringLiteral))) {
2359     bool RegularComments = [&]() {
2360       for (const FormatToken *T = &Current; T && T->is(TT_LineComment);
2361            T = T->Next) {
2362         if (!(T->TokenText.starts_with("//") || T->TokenText.starts_with("#")))
2363           return false;
2364       }
2365       return true;
2366     }();
2367     if (!Style.ReflowComments ||
2368         CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
2369         switchesFormatting(Current) || !RegularComments) {
2370       return nullptr;
2371     }
2372     return std::make_unique<BreakableLineCommentSection>(
2373         Current, StartColumn, /*InPPDirective=*/false, Encoding, Style);
2374   }
2375   return nullptr;
2376 }
2377 
2378 std::pair<unsigned, bool>
2379 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
2380                                            LineState &State, bool AllowBreak,
2381                                            bool DryRun, bool Strict) {
2382   std::unique_ptr<const BreakableToken> Token =
2383       createBreakableToken(Current, State, AllowBreak);
2384   if (!Token)
2385     return {0, false};
2386   assert(Token->getLineCount() > 0);
2387   unsigned ColumnLimit = getColumnLimit(State);
2388   if (Current.is(TT_LineComment)) {
2389     // We don't insert backslashes when breaking line comments.
2390     ColumnLimit = Style.ColumnLimit;
2391   }
2392   if (ColumnLimit == 0) {
2393     // To make the rest of the function easier set the column limit to the
2394     // maximum, if there should be no limit.
2395     ColumnLimit = std::numeric_limits<decltype(ColumnLimit)>::max();
2396   }
2397   if (Current.UnbreakableTailLength >= ColumnLimit)
2398     return {0, false};
2399   // ColumnWidth was already accounted into State.Column before calling
2400   // breakProtrudingToken.
2401   unsigned StartColumn = State.Column - Current.ColumnWidth;
2402   unsigned NewBreakPenalty = Current.isStringLiteral()
2403                                  ? Style.PenaltyBreakString
2404                                  : Style.PenaltyBreakComment;
2405   // Stores whether we intentionally decide to let a line exceed the column
2406   // limit.
2407   bool Exceeded = false;
2408   // Stores whether we introduce a break anywhere in the token.
2409   bool BreakInserted = Token->introducesBreakBeforeToken();
2410   // Store whether we inserted a new line break at the end of the previous
2411   // logical line.
2412   bool NewBreakBefore = false;
2413   // We use a conservative reflowing strategy. Reflow starts after a line is
2414   // broken or the corresponding whitespace compressed. Reflow ends as soon as a
2415   // line that doesn't get reflown with the previous line is reached.
2416   bool Reflow = false;
2417   // Keep track of where we are in the token:
2418   // Where we are in the content of the current logical line.
2419   unsigned TailOffset = 0;
2420   // The column number we're currently at.
2421   unsigned ContentStartColumn =
2422       Token->getContentStartColumn(0, /*Break=*/false);
2423   // The number of columns left in the current logical line after TailOffset.
2424   unsigned RemainingTokenColumns =
2425       Token->getRemainingLength(0, TailOffset, ContentStartColumn);
2426   // Adapt the start of the token, for example indent.
2427   if (!DryRun)
2428     Token->adaptStartOfLine(0, Whitespaces);
2429 
2430   unsigned ContentIndent = 0;
2431   unsigned Penalty = 0;
2432   LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
2433                           << StartColumn << ".\n");
2434   for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
2435        LineIndex != EndIndex; ++LineIndex) {
2436     LLVM_DEBUG(llvm::dbgs()
2437                << "  Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
2438     NewBreakBefore = false;
2439     // If we did reflow the previous line, we'll try reflowing again. Otherwise
2440     // we'll start reflowing if the current line is broken or whitespace is
2441     // compressed.
2442     bool TryReflow = Reflow;
2443     // Break the current token until we can fit the rest of the line.
2444     while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2445       LLVM_DEBUG(llvm::dbgs() << "    Over limit, need: "
2446                               << (ContentStartColumn + RemainingTokenColumns)
2447                               << ", space: " << ColumnLimit
2448                               << ", reflown prefix: " << ContentStartColumn
2449                               << ", offset in line: " << TailOffset << "\n");
2450       // If the current token doesn't fit, find the latest possible split in the
2451       // current line so that breaking at it will be under the column limit.
2452       // FIXME: Use the earliest possible split while reflowing to correctly
2453       // compress whitespace within a line.
2454       BreakableToken::Split Split =
2455           Token->getSplit(LineIndex, TailOffset, ColumnLimit,
2456                           ContentStartColumn, CommentPragmasRegex);
2457       if (Split.first == StringRef::npos) {
2458         // No break opportunity - update the penalty and continue with the next
2459         // logical line.
2460         if (LineIndex < EndIndex - 1) {
2461           // The last line's penalty is handled in addNextStateToQueue() or when
2462           // calling replaceWhitespaceAfterLastLine below.
2463           Penalty += Style.PenaltyExcessCharacter *
2464                      (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2465         }
2466         LLVM_DEBUG(llvm::dbgs() << "    No break opportunity.\n");
2467         break;
2468       }
2469       assert(Split.first != 0);
2470 
2471       if (Token->supportsReflow()) {
2472         // Check whether the next natural split point after the current one can
2473         // still fit the line, either because we can compress away whitespace,
2474         // or because the penalty the excess characters introduce is lower than
2475         // the break penalty.
2476         // We only do this for tokens that support reflowing, and thus allow us
2477         // to change the whitespace arbitrarily (e.g. comments).
2478         // Other tokens, like string literals, can be broken on arbitrary
2479         // positions.
2480 
2481         // First, compute the columns from TailOffset to the next possible split
2482         // position.
2483         // For example:
2484         // ColumnLimit:     |
2485         // // Some text   that    breaks
2486         //    ^ tail offset
2487         //             ^-- split
2488         //    ^-------- to split columns
2489         //                    ^--- next split
2490         //    ^--------------- to next split columns
2491         unsigned ToSplitColumns = Token->getRangeLength(
2492             LineIndex, TailOffset, Split.first, ContentStartColumn);
2493         LLVM_DEBUG(llvm::dbgs() << "    ToSplit: " << ToSplitColumns << "\n");
2494 
2495         BreakableToken::Split NextSplit = Token->getSplit(
2496             LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
2497             ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
2498         // Compute the columns necessary to fit the next non-breakable sequence
2499         // into the current line.
2500         unsigned ToNextSplitColumns = 0;
2501         if (NextSplit.first == StringRef::npos) {
2502           ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
2503                                                          ContentStartColumn);
2504         } else {
2505           ToNextSplitColumns = Token->getRangeLength(
2506               LineIndex, TailOffset,
2507               Split.first + Split.second + NextSplit.first, ContentStartColumn);
2508         }
2509         // Compress the whitespace between the break and the start of the next
2510         // unbreakable sequence.
2511         ToNextSplitColumns =
2512             Token->getLengthAfterCompression(ToNextSplitColumns, Split);
2513         LLVM_DEBUG(llvm::dbgs()
2514                    << "    ContentStartColumn: " << ContentStartColumn << "\n");
2515         LLVM_DEBUG(llvm::dbgs()
2516                    << "    ToNextSplit: " << ToNextSplitColumns << "\n");
2517         // If the whitespace compression makes us fit, continue on the current
2518         // line.
2519         bool ContinueOnLine =
2520             ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
2521         unsigned ExcessCharactersPenalty = 0;
2522         if (!ContinueOnLine && !Strict) {
2523           // Similarly, if the excess characters' penalty is lower than the
2524           // penalty of introducing a new break, continue on the current line.
2525           ExcessCharactersPenalty =
2526               (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
2527               Style.PenaltyExcessCharacter;
2528           LLVM_DEBUG(llvm::dbgs()
2529                      << "    Penalty excess: " << ExcessCharactersPenalty
2530                      << "\n            break : " << NewBreakPenalty << "\n");
2531           if (ExcessCharactersPenalty < NewBreakPenalty) {
2532             Exceeded = true;
2533             ContinueOnLine = true;
2534           }
2535         }
2536         if (ContinueOnLine) {
2537           LLVM_DEBUG(llvm::dbgs() << "    Continuing on line...\n");
2538           // The current line fits after compressing the whitespace - reflow
2539           // the next line into it if possible.
2540           TryReflow = true;
2541           if (!DryRun) {
2542             Token->compressWhitespace(LineIndex, TailOffset, Split,
2543                                       Whitespaces);
2544           }
2545           // When we continue on the same line, leave one space between content.
2546           ContentStartColumn += ToSplitColumns + 1;
2547           Penalty += ExcessCharactersPenalty;
2548           TailOffset += Split.first + Split.second;
2549           RemainingTokenColumns = Token->getRemainingLength(
2550               LineIndex, TailOffset, ContentStartColumn);
2551           continue;
2552         }
2553       }
2554       LLVM_DEBUG(llvm::dbgs() << "    Breaking...\n");
2555       // Update the ContentIndent only if the current line was not reflown with
2556       // the previous line, since in that case the previous line should still
2557       // determine the ContentIndent. Also never intent the last line.
2558       if (!Reflow)
2559         ContentIndent = Token->getContentIndent(LineIndex);
2560       LLVM_DEBUG(llvm::dbgs()
2561                  << "    ContentIndent: " << ContentIndent << "\n");
2562       ContentStartColumn = ContentIndent + Token->getContentStartColumn(
2563                                                LineIndex, /*Break=*/true);
2564 
2565       unsigned NewRemainingTokenColumns = Token->getRemainingLength(
2566           LineIndex, TailOffset + Split.first + Split.second,
2567           ContentStartColumn);
2568       if (NewRemainingTokenColumns == 0) {
2569         // No content to indent.
2570         ContentIndent = 0;
2571         ContentStartColumn =
2572             Token->getContentStartColumn(LineIndex, /*Break=*/true);
2573         NewRemainingTokenColumns = Token->getRemainingLength(
2574             LineIndex, TailOffset + Split.first + Split.second,
2575             ContentStartColumn);
2576       }
2577 
2578       // When breaking before a tab character, it may be moved by a few columns,
2579       // but will still be expanded to the next tab stop, so we don't save any
2580       // columns.
2581       if (NewRemainingTokenColumns >= RemainingTokenColumns) {
2582         // FIXME: Do we need to adjust the penalty?
2583         break;
2584       }
2585 
2586       LLVM_DEBUG(llvm::dbgs() << "    Breaking at: " << TailOffset + Split.first
2587                               << ", " << Split.second << "\n");
2588       if (!DryRun) {
2589         Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
2590                            Whitespaces);
2591       }
2592 
2593       Penalty += NewBreakPenalty;
2594       TailOffset += Split.first + Split.second;
2595       RemainingTokenColumns = NewRemainingTokenColumns;
2596       BreakInserted = true;
2597       NewBreakBefore = true;
2598     }
2599     // In case there's another line, prepare the state for the start of the next
2600     // line.
2601     if (LineIndex + 1 != EndIndex) {
2602       unsigned NextLineIndex = LineIndex + 1;
2603       if (NewBreakBefore) {
2604         // After breaking a line, try to reflow the next line into the current
2605         // one once RemainingTokenColumns fits.
2606         TryReflow = true;
2607       }
2608       if (TryReflow) {
2609         // We decided that we want to try reflowing the next line into the
2610         // current one.
2611         // We will now adjust the state as if the reflow is successful (in
2612         // preparation for the next line), and see whether that works. If we
2613         // decide that we cannot reflow, we will later reset the state to the
2614         // start of the next line.
2615         Reflow = false;
2616         // As we did not continue breaking the line, RemainingTokenColumns is
2617         // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2618         // the position at which we want to format the next line if we do
2619         // actually reflow.
2620         // When we reflow, we need to add a space between the end of the current
2621         // line and the next line's start column.
2622         ContentStartColumn += RemainingTokenColumns + 1;
2623         // Get the split that we need to reflow next logical line into the end
2624         // of the current one; the split will include any leading whitespace of
2625         // the next logical line.
2626         BreakableToken::Split SplitBeforeNext =
2627             Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2628         LLVM_DEBUG(llvm::dbgs()
2629                    << "    Size of reflown text: " << ContentStartColumn
2630                    << "\n    Potential reflow split: ");
2631         if (SplitBeforeNext.first != StringRef::npos) {
2632           LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2633                                   << SplitBeforeNext.second << "\n");
2634           TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2635           // If the rest of the next line fits into the current line below the
2636           // column limit, we can safely reflow.
2637           RemainingTokenColumns = Token->getRemainingLength(
2638               NextLineIndex, TailOffset, ContentStartColumn);
2639           Reflow = true;
2640           if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2641             LLVM_DEBUG(llvm::dbgs()
2642                        << "    Over limit after reflow, need: "
2643                        << (ContentStartColumn + RemainingTokenColumns)
2644                        << ", space: " << ColumnLimit
2645                        << ", reflown prefix: " << ContentStartColumn
2646                        << ", offset in line: " << TailOffset << "\n");
2647             // If the whole next line does not fit, try to find a point in
2648             // the next line at which we can break so that attaching the part
2649             // of the next line to that break point onto the current line is
2650             // below the column limit.
2651             BreakableToken::Split Split =
2652                 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2653                                 ContentStartColumn, CommentPragmasRegex);
2654             if (Split.first == StringRef::npos) {
2655               LLVM_DEBUG(llvm::dbgs() << "    Did not find later break\n");
2656               Reflow = false;
2657             } else {
2658               // Check whether the first split point gets us below the column
2659               // limit. Note that we will execute this split below as part of
2660               // the normal token breaking and reflow logic within the line.
2661               unsigned ToSplitColumns = Token->getRangeLength(
2662                   NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2663               if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2664                 LLVM_DEBUG(llvm::dbgs() << "    Next split protrudes, need: "
2665                                         << (ContentStartColumn + ToSplitColumns)
2666                                         << ", space: " << ColumnLimit);
2667                 unsigned ExcessCharactersPenalty =
2668                     (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2669                     Style.PenaltyExcessCharacter;
2670                 if (NewBreakPenalty < ExcessCharactersPenalty)
2671                   Reflow = false;
2672               }
2673             }
2674           }
2675         } else {
2676           LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2677         }
2678       }
2679       if (!Reflow) {
2680         // If we didn't reflow into the next line, the only space to consider is
2681         // the next logical line. Reset our state to match the start of the next
2682         // line.
2683         TailOffset = 0;
2684         ContentStartColumn =
2685             Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2686         RemainingTokenColumns = Token->getRemainingLength(
2687             NextLineIndex, TailOffset, ContentStartColumn);
2688         // Adapt the start of the token, for example indent.
2689         if (!DryRun)
2690           Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2691       } else {
2692         // If we found a reflow split and have added a new break before the next
2693         // line, we are going to remove the line break at the start of the next
2694         // logical line. For example, here we'll add a new line break after
2695         // 'text', and subsequently delete the line break between 'that' and
2696         // 'reflows'.
2697         //   // some text that
2698         //   // reflows
2699         // ->
2700         //   // some text
2701         //   // that reflows
2702         // When adding the line break, we also added the penalty for it, so we
2703         // need to subtract that penalty again when we remove the line break due
2704         // to reflowing.
2705         if (NewBreakBefore) {
2706           assert(Penalty >= NewBreakPenalty);
2707           Penalty -= NewBreakPenalty;
2708         }
2709         if (!DryRun)
2710           Token->reflow(NextLineIndex, Whitespaces);
2711       }
2712     }
2713   }
2714 
2715   BreakableToken::Split SplitAfterLastLine =
2716       Token->getSplitAfterLastLine(TailOffset);
2717   if (SplitAfterLastLine.first != StringRef::npos) {
2718     LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2719 
2720     // We add the last line's penalty here, since that line is going to be split
2721     // now.
2722     Penalty += Style.PenaltyExcessCharacter *
2723                (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2724 
2725     if (!DryRun) {
2726       Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2727                                             Whitespaces);
2728     }
2729     ContentStartColumn =
2730         Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2731     RemainingTokenColumns = Token->getRemainingLength(
2732         Token->getLineCount() - 1,
2733         TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2734         ContentStartColumn);
2735   }
2736 
2737   State.Column = ContentStartColumn + RemainingTokenColumns -
2738                  Current.UnbreakableTailLength;
2739 
2740   if (BreakInserted) {
2741     if (!DryRun)
2742       Token->updateAfterBroken(Whitespaces);
2743 
2744     // If we break the token inside a parameter list, we need to break before
2745     // the next parameter on all levels, so that the next parameter is clearly
2746     // visible. Line comments already introduce a break.
2747     if (Current.isNot(TT_LineComment))
2748       for (ParenState &Paren : State.Stack)
2749         Paren.BreakBeforeParameter = true;
2750 
2751     if (Current.is(TT_BlockComment))
2752       State.NoContinuation = true;
2753 
2754     State.Stack.back().LastSpace = StartColumn;
2755   }
2756 
2757   Token->updateNextToken(State);
2758 
2759   return {Penalty, Exceeded};
2760 }
2761 
2762 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2763   // In preprocessor directives reserve two chars for trailing " \".
2764   return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2765 }
2766 
2767 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2768   const FormatToken &Current = *State.NextToken;
2769   if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2770     return false;
2771   // We never consider raw string literals "multiline" for the purpose of
2772   // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2773   // (see TokenAnnotator::mustBreakBefore().
2774   if (Current.TokenText.starts_with("R\""))
2775     return false;
2776   if (Current.IsMultiline)
2777     return true;
2778   if (Current.getNextNonComment() &&
2779       Current.getNextNonComment()->isStringLiteral()) {
2780     return true; // Implicit concatenation.
2781   }
2782   if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2783       State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2784           Style.ColumnLimit) {
2785     return true; // String will be split.
2786   }
2787   return false;
2788 }
2789 
2790 } // namespace format
2791 } // namespace clang
2792