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
29namespace clang {
30namespace format {
31
32// Returns true if a TT_SelectorName should be indented when wrapped,
33// false otherwise.
34static 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.
41static 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.
49static 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
119static 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.
127static 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.
132static 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
149static 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.
162static 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.
187static StringRef
188getCanonicalRawStringDelimiter(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
196RawStringFormatStyleManager::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
218std::optional<FormatStyle>
219RawStringFormatStyleManager::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
226std::optional<FormatStyle>
227RawStringFormatStyleManager::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
235ContinuationIndenter::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
246LineState 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
290bool 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
363bool 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
623unsigned 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
662void 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        const auto *Prev = Current.Previous;
678        if (!Prev)
679          return false;
680        // For example, `/*Newline=*/false`.
681        if (Prev->is(TT_BlockComment) && Current.SpacesRequiredBefore == 0)
682          return false;
683        const auto *PrevNonComment = Current.getPreviousNonComment();
684        if (!PrevNonComment || PrevNonComment->isNot(tok::l_paren))
685          return false;
686        if (Current.isOneOf(tok::comment, tok::l_paren, TT_LambdaLSquare))
687          return false;
688        auto BlockParameterCount = PrevNonComment->BlockParameterCount;
689        if (BlockParameterCount == 0)
690          return false;
691
692        // Multiple lambdas in the same function call.
693        if (BlockParameterCount > 1)
694          return true;
695
696        // A lambda followed by another arg.
697        if (!PrevNonComment->Role)
698          return false;
699        auto Comma = PrevNonComment->Role->lastComma();
700        if (!Comma)
701          return false;
702        auto Next = Comma->getNextNonComment();
703        return Next &&
704               !Next->isOneOf(TT_LambdaLSquare, tok::l_brace, tok::caret);
705      }();
706
707  if (DisallowLineBreaksOnThisLine)
708    State.NoLineBreak = true;
709
710  if (Current.is(tok::equal) &&
711      (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
712      CurrentState.VariablePos == 0 &&
713      (!Previous.Previous ||
714       Previous.Previous->isNot(TT_DesignatedInitializerPeriod))) {
715    CurrentState.VariablePos = State.Column;
716    // Move over * and & if they are bound to the variable name.
717    const FormatToken *Tok = &Previous;
718    while (Tok && CurrentState.VariablePos >= Tok->ColumnWidth) {
719      CurrentState.VariablePos -= Tok->ColumnWidth;
720      if (Tok->SpacesRequiredBefore != 0)
721        break;
722      Tok = Tok->Previous;
723    }
724    if (Previous.PartOfMultiVariableDeclStmt)
725      CurrentState.LastSpace = CurrentState.VariablePos;
726  }
727
728  unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
729
730  // Indent preprocessor directives after the hash if required.
731  int PPColumnCorrection = 0;
732  if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
733      Previous.is(tok::hash) && State.FirstIndent > 0 &&
734      &Previous == State.Line->First &&
735      (State.Line->Type == LT_PreprocessorDirective ||
736       State.Line->Type == LT_ImportStatement)) {
737    Spaces += State.FirstIndent;
738
739    // For preprocessor indent with tabs, State.Column will be 1 because of the
740    // hash. This causes second-level indents onward to have an extra space
741    // after the tabs. We avoid this misalignment by subtracting 1 from the
742    // column value passed to replaceWhitespace().
743    if (Style.UseTab != FormatStyle::UT_Never)
744      PPColumnCorrection = -1;
745  }
746
747  if (!DryRun) {
748    Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
749                                  State.Column + Spaces + PPColumnCorrection,
750                                  /*IsAligned=*/false, State.Line->InMacroBody);
751  }
752
753  // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
754  // declaration unless there is multiple inheritance.
755  if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
756      Current.is(TT_InheritanceColon)) {
757    CurrentState.NoLineBreak = true;
758  }
759  if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
760      Previous.is(TT_InheritanceColon)) {
761    CurrentState.NoLineBreak = true;
762  }
763
764  if (Current.is(TT_SelectorName) && !CurrentState.ObjCSelectorNameFound) {
765    unsigned MinIndent = std::max(
766        State.FirstIndent + Style.ContinuationIndentWidth, CurrentState.Indent);
767    unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
768    if (Current.LongestObjCSelectorName == 0)
769      CurrentState.AlignColons = false;
770    else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
771      CurrentState.ColonPos = MinIndent + Current.LongestObjCSelectorName;
772    else
773      CurrentState.ColonPos = FirstColonPos;
774  }
775
776  // In "AlwaysBreak" or "BlockIndent" mode, enforce wrapping directly after the
777  // parenthesis by disallowing any further line breaks if there is no line
778  // break after the opening parenthesis. Don't break if it doesn't conserve
779  // columns.
780  auto IsOpeningBracket = [&](const FormatToken &Tok) {
781    auto IsStartOfBracedList = [&]() {
782      return Tok.is(tok::l_brace) && Tok.isNot(BK_Block) &&
783             Style.Cpp11BracedListStyle;
784    };
785    if (!Tok.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
786        !IsStartOfBracedList()) {
787      return false;
788    }
789    if (!Tok.Previous)
790      return true;
791    if (Tok.Previous->isIf())
792      return Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak;
793    return !Tok.Previous->isOneOf(TT_CastRParen, tok::kw_for, tok::kw_while,
794                                  tok::kw_switch);
795  };
796  if ((Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak ||
797       Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent) &&
798      IsOpeningBracket(Previous) && State.Column > getNewLineColumn(State) &&
799      // Don't do this for simple (no expressions) one-argument function calls
800      // as that feels like needlessly wasting whitespace, e.g.:
801      //
802      //   caaaaaaaaaaaall(
803      //       caaaaaaaaaaaall(
804      //           caaaaaaaaaaaall(
805      //               caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
806      Current.FakeLParens.size() > 0 &&
807      Current.FakeLParens.back() > prec::Unknown) {
808    CurrentState.NoLineBreak = true;
809  }
810  if (Previous.is(TT_TemplateString) && Previous.opensScope())
811    CurrentState.NoLineBreak = true;
812
813  // Align following lines within parentheses / brackets if configured.
814  // Note: This doesn't apply to macro expansion lines, which are MACRO( , , )
815  // with args as children of the '(' and ',' tokens. It does not make sense to
816  // align the commas with the opening paren.
817  if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
818      !CurrentState.IsCSharpGenericTypeConstraint && Previous.opensScope() &&
819      Previous.isNot(TT_ObjCMethodExpr) && Previous.isNot(TT_RequiresClause) &&
820      !(Current.MacroParent && Previous.MacroParent) &&
821      (Current.isNot(TT_LineComment) ||
822       Previous.isOneOf(BK_BracedInit, TT_VerilogMultiLineListLParen))) {
823    CurrentState.Indent = State.Column + Spaces;
824    CurrentState.IsAligned = true;
825  }
826  if (CurrentState.AvoidBinPacking && startsNextParameter(Current, Style))
827    CurrentState.NoLineBreak = true;
828  if (startsSegmentOfBuilderTypeCall(Current) &&
829      State.Column > getNewLineColumn(State)) {
830    CurrentState.ContainsUnwrappedBuilder = true;
831  }
832
833  if (Current.is(TT_TrailingReturnArrow) &&
834      Style.Language == FormatStyle::LK_Java) {
835    CurrentState.NoLineBreak = true;
836  }
837  if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
838      (Previous.MatchingParen &&
839       (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10))) {
840    // If there is a function call with long parameters, break before trailing
841    // calls. This prevents things like:
842    //   EXPECT_CALL(SomeLongParameter).Times(
843    //       2);
844    // We don't want to do this for short parameters as they can just be
845    // indexes.
846    CurrentState.NoLineBreak = true;
847  }
848
849  // Don't allow the RHS of an operator to be split over multiple lines unless
850  // there is a line-break right after the operator.
851  // Exclude relational operators, as there, it is always more desirable to
852  // have the LHS 'left' of the RHS.
853  const FormatToken *P = Current.getPreviousNonComment();
854  if (Current.isNot(tok::comment) && P &&
855      (P->isOneOf(TT_BinaryOperator, tok::comma) ||
856       (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
857      !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
858      P->getPrecedence() != prec::Assignment &&
859      P->getPrecedence() != prec::Relational &&
860      P->getPrecedence() != prec::Spaceship) {
861    bool BreakBeforeOperator =
862        P->MustBreakBefore || P->is(tok::lessless) ||
863        (P->is(TT_BinaryOperator) &&
864         Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
865        (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
866    // Don't do this if there are only two operands. In these cases, there is
867    // always a nice vertical separation between them and the extra line break
868    // does not help.
869    bool HasTwoOperands = P->OperatorIndex == 0 && !P->NextOperator &&
870                          P->isNot(TT_ConditionalExpr);
871    if ((!BreakBeforeOperator &&
872         !(HasTwoOperands &&
873           Style.AlignOperands != FormatStyle::OAS_DontAlign)) ||
874        (!CurrentState.LastOperatorWrapped && BreakBeforeOperator)) {
875      CurrentState.NoLineBreakInOperand = true;
876    }
877  }
878
879  State.Column += Spaces;
880  if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
881      Previous.Previous &&
882      (Previous.Previous->is(tok::kw_for) || Previous.Previous->isIf())) {
883    // Treat the condition inside an if as if it was a second function
884    // parameter, i.e. let nested calls have a continuation indent.
885    CurrentState.LastSpace = State.Column;
886    CurrentState.NestedBlockIndent = State.Column;
887  } else if (!Current.isOneOf(tok::comment, tok::caret) &&
888             ((Previous.is(tok::comma) &&
889               Previous.isNot(TT_OverloadedOperator)) ||
890              (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
891    CurrentState.LastSpace = State.Column;
892  } else if (Previous.is(TT_CtorInitializerColon) &&
893             (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
894             Style.BreakConstructorInitializers ==
895                 FormatStyle::BCIS_AfterColon) {
896    CurrentState.Indent = State.Column;
897    CurrentState.LastSpace = State.Column;
898  } else if (Previous.isOneOf(TT_ConditionalExpr, TT_CtorInitializerColon)) {
899    CurrentState.LastSpace = State.Column;
900  } else if (Previous.is(TT_BinaryOperator) &&
901             ((Previous.getPrecedence() != prec::Assignment &&
902               (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
903                Previous.NextOperator)) ||
904              Current.StartsBinaryExpression)) {
905    // Indent relative to the RHS of the expression unless this is a simple
906    // assignment without binary expression on the RHS.
907    if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
908      CurrentState.LastSpace = State.Column;
909  } else if (Previous.is(TT_InheritanceColon)) {
910    CurrentState.Indent = State.Column;
911    CurrentState.LastSpace = State.Column;
912  } else if (Current.is(TT_CSharpGenericTypeConstraintColon)) {
913    CurrentState.ColonPos = State.Column;
914  } else if (Previous.opensScope()) {
915    // If a function has a trailing call, indent all parameters from the
916    // opening parenthesis. This avoids confusing indents like:
917    //   OuterFunction(InnerFunctionCall( // break
918    //       ParameterToInnerFunction))   // break
919    //       .SecondInnerFunctionCall();
920    if (Previous.MatchingParen) {
921      const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
922      if (Next && Next->isMemberAccess() && State.Stack.size() > 1 &&
923          State.Stack[State.Stack.size() - 2].CallContinuation == 0) {
924        CurrentState.LastSpace = State.Column;
925      }
926    }
927  }
928}
929
930unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
931                                                 bool DryRun) {
932  FormatToken &Current = *State.NextToken;
933  assert(State.NextToken->Previous);
934  const FormatToken &Previous = *State.NextToken->Previous;
935  auto &CurrentState = State.Stack.back();
936
937  // Extra penalty that needs to be added because of the way certain line
938  // breaks are chosen.
939  unsigned Penalty = 0;
940
941  const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
942  const FormatToken *NextNonComment = Previous.getNextNonComment();
943  if (!NextNonComment)
944    NextNonComment = &Current;
945  // The first line break on any NestingLevel causes an extra penalty in order
946  // prefer similar line breaks.
947  if (!CurrentState.ContainsLineBreak)
948    Penalty += 15;
949  CurrentState.ContainsLineBreak = true;
950
951  Penalty += State.NextToken->SplitPenalty;
952
953  // Breaking before the first "<<" is generally not desirable if the LHS is
954  // short. Also always add the penalty if the LHS is split over multiple lines
955  // to avoid unnecessary line breaks that just work around this penalty.
956  if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess == 0 &&
957      (State.Column <= Style.ColumnLimit / 3 ||
958       CurrentState.BreakBeforeParameter)) {
959    Penalty += Style.PenaltyBreakFirstLessLess;
960  }
961
962  State.Column = getNewLineColumn(State);
963
964  // Add Penalty proportional to amount of whitespace away from FirstColumn
965  // This tends to penalize several lines that are far-right indented,
966  // and prefers a line-break prior to such a block, e.g:
967  //
968  // Constructor() :
969  //   member(value), looooooooooooooooong_member(
970  //                      looooooooooong_call(param_1, param_2, param_3))
971  // would then become
972  // Constructor() :
973  //   member(value),
974  //   looooooooooooooooong_member(
975  //       looooooooooong_call(param_1, param_2, param_3))
976  if (State.Column > State.FirstIndent) {
977    Penalty +=
978        Style.PenaltyIndentedWhitespace * (State.Column - State.FirstIndent);
979  }
980
981  // Indent nested blocks relative to this column, unless in a very specific
982  // JavaScript special case where:
983  //
984  //   var loooooong_name =
985  //       function() {
986  //     // code
987  //   }
988  //
989  // is common and should be formatted like a free-standing function. The same
990  // goes for wrapping before the lambda return type arrow.
991  if (Current.isNot(TT_TrailingReturnArrow) &&
992      (!Style.isJavaScript() || Current.NestingLevel != 0 ||
993       !PreviousNonComment || PreviousNonComment->isNot(tok::equal) ||
994       !Current.isOneOf(Keywords.kw_async, Keywords.kw_function))) {
995    CurrentState.NestedBlockIndent = State.Column;
996  }
997
998  if (NextNonComment->isMemberAccess()) {
999    if (CurrentState.CallContinuation == 0)
1000      CurrentState.CallContinuation = State.Column;
1001  } else if (NextNonComment->is(TT_SelectorName)) {
1002    if (!CurrentState.ObjCSelectorNameFound) {
1003      if (NextNonComment->LongestObjCSelectorName == 0) {
1004        CurrentState.AlignColons = false;
1005      } else {
1006        CurrentState.ColonPos =
1007            (shouldIndentWrappedSelectorName(Style, State.Line->Type)
1008                 ? std::max(CurrentState.Indent,
1009                            State.FirstIndent + Style.ContinuationIndentWidth)
1010                 : CurrentState.Indent) +
1011            std::max(NextNonComment->LongestObjCSelectorName,
1012                     NextNonComment->ColumnWidth);
1013      }
1014    } else if (CurrentState.AlignColons &&
1015               CurrentState.ColonPos <= NextNonComment->ColumnWidth) {
1016      CurrentState.ColonPos = State.Column + NextNonComment->ColumnWidth;
1017    }
1018  } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1019             PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1020    // FIXME: This is hacky, find a better way. The problem is that in an ObjC
1021    // method expression, the block should be aligned to the line starting it,
1022    // e.g.:
1023    //   [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
1024    //                        ^(int *i) {
1025    //                            // ...
1026    //                        }];
1027    // Thus, we set LastSpace of the next higher NestingLevel, to which we move
1028    // when we consume all of the "}"'s FakeRParens at the "{".
1029    if (State.Stack.size() > 1) {
1030      State.Stack[State.Stack.size() - 2].LastSpace =
1031          std::max(CurrentState.LastSpace, CurrentState.Indent) +
1032          Style.ContinuationIndentWidth;
1033    }
1034  }
1035
1036  if ((PreviousNonComment &&
1037       PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
1038       !CurrentState.AvoidBinPacking) ||
1039      Previous.is(TT_BinaryOperator)) {
1040    CurrentState.BreakBeforeParameter = false;
1041  }
1042  if (PreviousNonComment &&
1043      (PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) ||
1044       PreviousNonComment->ClosesRequiresClause) &&
1045      Current.NestingLevel == 0) {
1046    CurrentState.BreakBeforeParameter = false;
1047  }
1048  if (NextNonComment->is(tok::question) ||
1049      (PreviousNonComment && PreviousNonComment->is(tok::question))) {
1050    CurrentState.BreakBeforeParameter = true;
1051  }
1052  if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
1053    CurrentState.BreakBeforeParameter = false;
1054
1055  if (!DryRun) {
1056    unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
1057    if (Current.is(tok::r_brace) && Current.MatchingParen &&
1058        // Only strip trailing empty lines for l_braces that have children, i.e.
1059        // for function expressions (lambdas, arrows, etc).
1060        !Current.MatchingParen->Children.empty()) {
1061      // lambdas and arrow functions are expressions, thus their r_brace is not
1062      // on its own line, and thus not covered by UnwrappedLineFormatter's logic
1063      // about removing empty lines on closing blocks. Special case them here.
1064      MaxEmptyLinesToKeep = 1;
1065    }
1066    unsigned Newlines =
1067        std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
1068    bool ContinuePPDirective =
1069        State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
1070    Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
1071                                  CurrentState.IsAligned, ContinuePPDirective);
1072  }
1073
1074  if (!Current.isTrailingComment())
1075    CurrentState.LastSpace = State.Column;
1076  if (Current.is(tok::lessless)) {
1077    // If we are breaking before a "<<", we always want to indent relative to
1078    // RHS. This is necessary only for "<<", as we special-case it and don't
1079    // always indent relative to the RHS.
1080    CurrentState.LastSpace += 3; // 3 -> width of "<< ".
1081  }
1082
1083  State.StartOfLineLevel = Current.NestingLevel;
1084  State.LowestLevelOnLine = Current.NestingLevel;
1085
1086  // Any break on this level means that the parent level has been broken
1087  // and we need to avoid bin packing there.
1088  bool NestedBlockSpecialCase =
1089      (!Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
1090       State.Stack[State.Stack.size() - 2].NestedBlockInlined) ||
1091      (Style.Language == FormatStyle::LK_ObjC && Current.is(tok::r_brace) &&
1092       State.Stack.size() > 1 && !Style.ObjCBreakBeforeNestedBlockParam);
1093  // Do not force parameter break for statements with requires expressions.
1094  NestedBlockSpecialCase =
1095      NestedBlockSpecialCase ||
1096      (Current.MatchingParen &&
1097       Current.MatchingParen->is(TT_RequiresExpressionLBrace));
1098  if (!NestedBlockSpecialCase) {
1099    auto ParentLevelIt = std::next(State.Stack.rbegin());
1100    if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1101        Current.MatchingParen && Current.MatchingParen->is(TT_LambdaLBrace)) {
1102      // If the first character on the new line is a lambda's closing brace, the
1103      // stack still contains that lambda's parenthesis. As such, we need to
1104      // recurse further down the stack than usual to find the parenthesis level
1105      // containing the lambda, which is where we want to set
1106      // BreakBeforeParameter.
1107      //
1108      // We specifically special case "OuterScope"-formatted lambdas here
1109      // because, when using that setting, breaking before the parameter
1110      // directly following the lambda is particularly unsightly. However, when
1111      // "OuterScope" is not set, the logic to find the parent parenthesis level
1112      // still appears to be sometimes incorrect. It has not been fixed yet
1113      // because it would lead to significant changes in existing behaviour.
1114      //
1115      // TODO: fix the non-"OuterScope" case too.
1116      auto FindCurrentLevel = [&](const auto &It) {
1117        return std::find_if(It, State.Stack.rend(), [](const auto &PState) {
1118          return PState.Tok != nullptr; // Ignore fake parens.
1119        });
1120      };
1121      auto MaybeIncrement = [&](const auto &It) {
1122        return It != State.Stack.rend() ? std::next(It) : It;
1123      };
1124      auto LambdaLevelIt = FindCurrentLevel(State.Stack.rbegin());
1125      auto LevelContainingLambdaIt =
1126          FindCurrentLevel(MaybeIncrement(LambdaLevelIt));
1127      ParentLevelIt = MaybeIncrement(LevelContainingLambdaIt);
1128    }
1129    for (auto I = ParentLevelIt, E = State.Stack.rend(); I != E; ++I)
1130      I->BreakBeforeParameter = true;
1131  }
1132
1133  if (PreviousNonComment &&
1134      !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
1135      ((PreviousNonComment->isNot(TT_TemplateCloser) &&
1136        !PreviousNonComment->ClosesRequiresClause) ||
1137       Current.NestingLevel != 0) &&
1138      !PreviousNonComment->isOneOf(
1139          TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
1140          TT_LeadingJavaAnnotation) &&
1141      Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope() &&
1142      // We don't want to enforce line breaks for subsequent arguments just
1143      // because we have been forced to break before a lambda body.
1144      (!Style.BraceWrapping.BeforeLambdaBody ||
1145       Current.isNot(TT_LambdaLBrace))) {
1146    CurrentState.BreakBeforeParameter = true;
1147  }
1148
1149  // If we break after { or the [ of an array initializer, we should also break
1150  // before the corresponding } or ].
1151  if (PreviousNonComment &&
1152      (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1153       opensProtoMessageField(*PreviousNonComment, Style))) {
1154    CurrentState.BreakBeforeClosingBrace = true;
1155  }
1156
1157  if (PreviousNonComment && PreviousNonComment->is(tok::l_paren)) {
1158    CurrentState.BreakBeforeClosingParen =
1159        Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent;
1160  }
1161
1162  if (CurrentState.AvoidBinPacking) {
1163    // If we are breaking after '(', '{', '<', or this is the break after a ':'
1164    // to start a member initializer list in a constructor, this should not
1165    // be considered bin packing unless the relevant AllowAll option is false or
1166    // this is a dict/object literal.
1167    bool PreviousIsBreakingCtorInitializerColon =
1168        PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1169        Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
1170    bool AllowAllConstructorInitializersOnNextLine =
1171        Style.PackConstructorInitializers == FormatStyle::PCIS_NextLine ||
1172        Style.PackConstructorInitializers == FormatStyle::PCIS_NextLineOnly;
1173    if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
1174          PreviousIsBreakingCtorInitializerColon) ||
1175        (!Style.AllowAllParametersOfDeclarationOnNextLine &&
1176         State.Line->MustBeDeclaration) ||
1177        (!Style.AllowAllArgumentsOnNextLine &&
1178         !State.Line->MustBeDeclaration) ||
1179        (!AllowAllConstructorInitializersOnNextLine &&
1180         PreviousIsBreakingCtorInitializerColon) ||
1181        Previous.is(TT_DictLiteral)) {
1182      CurrentState.BreakBeforeParameter = true;
1183    }
1184
1185    // If we are breaking after a ':' to start a member initializer list,
1186    // and we allow all arguments on the next line, we should not break
1187    // before the next parameter.
1188    if (PreviousIsBreakingCtorInitializerColon &&
1189        AllowAllConstructorInitializersOnNextLine) {
1190      CurrentState.BreakBeforeParameter = false;
1191    }
1192  }
1193
1194  return Penalty;
1195}
1196
1197unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
1198  if (!State.NextToken || !State.NextToken->Previous)
1199    return 0;
1200
1201  FormatToken &Current = *State.NextToken;
1202  const auto &CurrentState = State.Stack.back();
1203
1204  if (CurrentState.IsCSharpGenericTypeConstraint &&
1205      Current.isNot(TT_CSharpGenericTypeConstraint)) {
1206    return CurrentState.ColonPos + 2;
1207  }
1208
1209  const FormatToken &Previous = *Current.Previous;
1210  // If we are continuing an expression, we want to use the continuation indent.
1211  unsigned ContinuationIndent =
1212      std::max(CurrentState.LastSpace, CurrentState.Indent) +
1213      Style.ContinuationIndentWidth;
1214  const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
1215  const FormatToken *NextNonComment = Previous.getNextNonComment();
1216  if (!NextNonComment)
1217    NextNonComment = &Current;
1218
1219  // Java specific bits.
1220  if (Style.Language == FormatStyle::LK_Java &&
1221      Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends)) {
1222    return std::max(CurrentState.LastSpace,
1223                    CurrentState.Indent + Style.ContinuationIndentWidth);
1224  }
1225
1226  // Indentation of the statement following a Verilog case label is taken care
1227  // of in moveStateToNextToken.
1228  if (Style.isVerilog() && PreviousNonComment &&
1229      Keywords.isVerilogEndOfLabel(*PreviousNonComment)) {
1230    return State.FirstIndent;
1231  }
1232
1233  if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths &&
1234      State.Line->First->is(tok::kw_enum)) {
1235    return (Style.IndentWidth * State.Line->First->IndentLevel) +
1236           Style.IndentWidth;
1237  }
1238
1239  if ((NextNonComment->is(tok::l_brace) && NextNonComment->is(BK_Block)) ||
1240      (Style.isVerilog() && Keywords.isVerilogBegin(*NextNonComment))) {
1241    if (Current.NestingLevel == 0 ||
1242        (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1243         State.NextToken->is(TT_LambdaLBrace))) {
1244      return State.FirstIndent;
1245    }
1246    return CurrentState.Indent;
1247  }
1248  if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
1249       (Current.is(tok::greater) && Style.isProto())) &&
1250      State.Stack.size() > 1) {
1251    if (Current.closesBlockOrBlockTypeList(Style))
1252      return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
1253    if (Current.MatchingParen && Current.MatchingParen->is(BK_BracedInit))
1254      return State.Stack[State.Stack.size() - 2].LastSpace;
1255    return State.FirstIndent;
1256  }
1257  // Indent a closing parenthesis at the previous level if followed by a semi,
1258  // const, or opening brace. This allows indentations such as:
1259  //     foo(
1260  //       a,
1261  //     );
1262  //     int Foo::getter(
1263  //         //
1264  //     ) const {
1265  //       return foo;
1266  //     }
1267  //     function foo(
1268  //       a,
1269  //     ) {
1270  //       code(); //
1271  //     }
1272  if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
1273      (!Current.Next ||
1274       Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace))) {
1275    return State.Stack[State.Stack.size() - 2].LastSpace;
1276  }
1277  if (Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent &&
1278      (Current.is(tok::r_paren) ||
1279       (Current.is(tok::r_brace) && Current.MatchingParen &&
1280        Current.MatchingParen->is(BK_BracedInit))) &&
1281      State.Stack.size() > 1) {
1282    return State.Stack[State.Stack.size() - 2].LastSpace;
1283  }
1284  if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
1285    return State.Stack[State.Stack.size() - 2].LastSpace;
1286  // Field labels in a nested type should be aligned to the brace. For example
1287  // in ProtoBuf:
1288  //   optional int32 b = 2 [(foo_options) = {aaaaaaaaaaaaaaaaaaa: 123,
1289  //                                          bbbbbbbbbbbbbbbbbbbbbbbb:"baz"}];
1290  // For Verilog, a quote following a brace is treated as an identifier.  And
1291  // Both braces and colons get annotated as TT_DictLiteral.  So we have to
1292  // check.
1293  if (Current.is(tok::identifier) && Current.Next &&
1294      (!Style.isVerilog() || Current.Next->is(tok::colon)) &&
1295      (Current.Next->is(TT_DictLiteral) ||
1296       (Style.isProto() && Current.Next->isOneOf(tok::less, tok::l_brace)))) {
1297    return CurrentState.Indent;
1298  }
1299  if (NextNonComment->is(TT_ObjCStringLiteral) &&
1300      State.StartOfStringLiteral != 0) {
1301    return State.StartOfStringLiteral - 1;
1302  }
1303  if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
1304    return State.StartOfStringLiteral;
1305  if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess != 0)
1306    return CurrentState.FirstLessLess;
1307  if (NextNonComment->isMemberAccess()) {
1308    if (CurrentState.CallContinuation == 0)
1309      return ContinuationIndent;
1310    return CurrentState.CallContinuation;
1311  }
1312  if (CurrentState.QuestionColumn != 0 &&
1313      ((NextNonComment->is(tok::colon) &&
1314        NextNonComment->is(TT_ConditionalExpr)) ||
1315       Previous.is(TT_ConditionalExpr))) {
1316    if (((NextNonComment->is(tok::colon) && NextNonComment->Next &&
1317          !NextNonComment->Next->FakeLParens.empty() &&
1318          NextNonComment->Next->FakeLParens.back() == prec::Conditional) ||
1319         (Previous.is(tok::colon) && !Current.FakeLParens.empty() &&
1320          Current.FakeLParens.back() == prec::Conditional)) &&
1321        !CurrentState.IsWrappedConditional) {
1322      // NOTE: we may tweak this slightly:
1323      //    * not remove the 'lead' ContinuationIndentWidth
1324      //    * always un-indent by the operator when
1325      //    BreakBeforeTernaryOperators=true
1326      unsigned Indent = CurrentState.Indent;
1327      if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1328        Indent -= Style.ContinuationIndentWidth;
1329      if (Style.BreakBeforeTernaryOperators && CurrentState.UnindentOperator)
1330        Indent -= 2;
1331      return Indent;
1332    }
1333    return CurrentState.QuestionColumn;
1334  }
1335  if (Previous.is(tok::comma) && CurrentState.VariablePos != 0)
1336    return CurrentState.VariablePos;
1337  if (Current.is(TT_RequiresClause)) {
1338    if (Style.IndentRequiresClause)
1339      return CurrentState.Indent + Style.IndentWidth;
1340    switch (Style.RequiresClausePosition) {
1341    case FormatStyle::RCPS_OwnLine:
1342    case FormatStyle::RCPS_WithFollowing:
1343      return CurrentState.Indent;
1344    default:
1345      break;
1346    }
1347  }
1348  if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1349                              TT_InheritanceComma)) {
1350    return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1351  }
1352  if ((PreviousNonComment &&
1353       (PreviousNonComment->ClosesTemplateDeclaration ||
1354        PreviousNonComment->ClosesRequiresClause ||
1355        (PreviousNonComment->is(TT_AttributeMacro) &&
1356         Current.isNot(tok::l_paren)) ||
1357        PreviousNonComment->isOneOf(
1358            TT_AttributeRParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
1359            TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
1360      (!Style.IndentWrappedFunctionNames &&
1361       NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName))) {
1362    return std::max(CurrentState.LastSpace, CurrentState.Indent);
1363  }
1364  if (NextNonComment->is(TT_SelectorName)) {
1365    if (!CurrentState.ObjCSelectorNameFound) {
1366      unsigned MinIndent = CurrentState.Indent;
1367      if (shouldIndentWrappedSelectorName(Style, State.Line->Type)) {
1368        MinIndent = std::max(MinIndent,
1369                             State.FirstIndent + Style.ContinuationIndentWidth);
1370      }
1371      // If LongestObjCSelectorName is 0, we are indenting the first
1372      // part of an ObjC selector (or a selector component which is
1373      // not colon-aligned due to block formatting).
1374      //
1375      // Otherwise, we are indenting a subsequent part of an ObjC
1376      // selector which should be colon-aligned to the longest
1377      // component of the ObjC selector.
1378      //
1379      // In either case, we want to respect Style.IndentWrappedFunctionNames.
1380      return MinIndent +
1381             std::max(NextNonComment->LongestObjCSelectorName,
1382                      NextNonComment->ColumnWidth) -
1383             NextNonComment->ColumnWidth;
1384    }
1385    if (!CurrentState.AlignColons)
1386      return CurrentState.Indent;
1387    if (CurrentState.ColonPos > NextNonComment->ColumnWidth)
1388      return CurrentState.ColonPos - NextNonComment->ColumnWidth;
1389    return CurrentState.Indent;
1390  }
1391  if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1392    return CurrentState.ColonPos;
1393  if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1394    if (CurrentState.StartOfArraySubscripts != 0) {
1395      return CurrentState.StartOfArraySubscripts;
1396    } else if (Style.isCSharp()) { // C# allows `["key"] = value` inside object
1397                                   // initializers.
1398      return CurrentState.Indent;
1399    }
1400    return ContinuationIndent;
1401  }
1402
1403  // OpenMP clauses want to get additional indentation when they are pushed onto
1404  // the next line.
1405  if (State.Line->InPragmaDirective) {
1406    FormatToken *PragmaType = State.Line->First->Next->Next;
1407    if (PragmaType && PragmaType->TokenText.equals("omp"))
1408      return CurrentState.Indent + Style.ContinuationIndentWidth;
1409  }
1410
1411  // This ensure that we correctly format ObjC methods calls without inputs,
1412  // i.e. where the last element isn't selector like: [callee method];
1413  if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1414      NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr)) {
1415    return CurrentState.Indent;
1416  }
1417
1418  if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1419      Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon)) {
1420    return ContinuationIndent;
1421  }
1422  if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1423      PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1424    return ContinuationIndent;
1425  }
1426  if (NextNonComment->is(TT_CtorInitializerComma))
1427    return CurrentState.Indent;
1428  if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1429      Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1430    return CurrentState.Indent;
1431  }
1432  if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1433      Style.BreakInheritanceList == FormatStyle::BILS_AfterColon) {
1434    return CurrentState.Indent;
1435  }
1436  if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() &&
1437      !Current.isOneOf(tok::colon, tok::comment)) {
1438    return ContinuationIndent;
1439  }
1440  if (Current.is(TT_ProtoExtensionLSquare))
1441    return CurrentState.Indent;
1442  if (Current.isBinaryOperator() && CurrentState.UnindentOperator) {
1443    return CurrentState.Indent - Current.Tok.getLength() -
1444           Current.SpacesRequiredBefore;
1445  }
1446  if (Current.is(tok::comment) && NextNonComment->isBinaryOperator() &&
1447      CurrentState.UnindentOperator) {
1448    return CurrentState.Indent - NextNonComment->Tok.getLength() -
1449           NextNonComment->SpacesRequiredBefore;
1450  }
1451  if (CurrentState.Indent == State.FirstIndent && PreviousNonComment &&
1452      !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma)) {
1453    // Ensure that we fall back to the continuation indent width instead of
1454    // just flushing continuations left.
1455    return CurrentState.Indent + Style.ContinuationIndentWidth;
1456  }
1457  return CurrentState.Indent;
1458}
1459
1460static bool hasNestedBlockInlined(const FormatToken *Previous,
1461                                  const FormatToken &Current,
1462                                  const FormatStyle &Style) {
1463  if (Previous->isNot(tok::l_paren))
1464    return true;
1465  if (Previous->ParameterCount > 1)
1466    return true;
1467
1468  // Also a nested block if contains a lambda inside function with 1 parameter.
1469  return Style.BraceWrapping.BeforeLambdaBody && Current.is(TT_LambdaLSquare);
1470}
1471
1472unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1473                                                    bool DryRun, bool Newline) {
1474  assert(State.Stack.size());
1475  const FormatToken &Current = *State.NextToken;
1476  auto &CurrentState = State.Stack.back();
1477
1478  if (Current.is(TT_CSharpGenericTypeConstraint))
1479    CurrentState.IsCSharpGenericTypeConstraint = true;
1480  if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1481    CurrentState.NoLineBreakInOperand = false;
1482  if (Current.isOneOf(TT_InheritanceColon, TT_CSharpGenericTypeConstraintColon))
1483    CurrentState.AvoidBinPacking = true;
1484  if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1485    if (CurrentState.FirstLessLess == 0)
1486      CurrentState.FirstLessLess = State.Column;
1487    else
1488      CurrentState.LastOperatorWrapped = Newline;
1489  }
1490  if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1491    CurrentState.LastOperatorWrapped = Newline;
1492  if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1493      Current.Previous->isNot(TT_ConditionalExpr)) {
1494    CurrentState.LastOperatorWrapped = Newline;
1495  }
1496  if (Current.is(TT_ArraySubscriptLSquare) &&
1497      CurrentState.StartOfArraySubscripts == 0) {
1498    CurrentState.StartOfArraySubscripts = State.Column;
1499  }
1500
1501  auto IsWrappedConditional = [](const FormatToken &Tok) {
1502    if (!(Tok.is(TT_ConditionalExpr) && Tok.is(tok::question)))
1503      return false;
1504    if (Tok.MustBreakBefore)
1505      return true;
1506
1507    const FormatToken *Next = Tok.getNextNonComment();
1508    return Next && Next->MustBreakBefore;
1509  };
1510  if (IsWrappedConditional(Current))
1511    CurrentState.IsWrappedConditional = true;
1512  if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1513    CurrentState.QuestionColumn = State.Column;
1514  if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1515    const FormatToken *Previous = Current.Previous;
1516    while (Previous && Previous->isTrailingComment())
1517      Previous = Previous->Previous;
1518    if (Previous && Previous->is(tok::question))
1519      CurrentState.QuestionColumn = State.Column;
1520  }
1521  if (!Current.opensScope() && !Current.closesScope() &&
1522      Current.isNot(TT_PointerOrReference)) {
1523    State.LowestLevelOnLine =
1524        std::min(State.LowestLevelOnLine, Current.NestingLevel);
1525  }
1526  if (Current.isMemberAccess())
1527    CurrentState.StartOfFunctionCall = !Current.NextOperator ? 0 : State.Column;
1528  if (Current.is(TT_SelectorName))
1529    CurrentState.ObjCSelectorNameFound = true;
1530  if (Current.is(TT_CtorInitializerColon) &&
1531      Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1532    // Indent 2 from the column, so:
1533    // SomeClass::SomeClass()
1534    //     : First(...), ...
1535    //       Next(...)
1536    //       ^ line up here.
1537    CurrentState.Indent = State.Column + (Style.BreakConstructorInitializers ==
1538                                                  FormatStyle::BCIS_BeforeComma
1539                                              ? 0
1540                                              : 2);
1541    CurrentState.NestedBlockIndent = CurrentState.Indent;
1542    if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack) {
1543      CurrentState.AvoidBinPacking = true;
1544      CurrentState.BreakBeforeParameter =
1545          Style.ColumnLimit > 0 &&
1546          Style.PackConstructorInitializers != FormatStyle::PCIS_NextLine &&
1547          Style.PackConstructorInitializers != FormatStyle::PCIS_NextLineOnly;
1548    } else {
1549      CurrentState.BreakBeforeParameter = false;
1550    }
1551  }
1552  if (Current.is(TT_CtorInitializerColon) &&
1553      Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1554    CurrentState.Indent =
1555        State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1556    CurrentState.NestedBlockIndent = CurrentState.Indent;
1557    if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack)
1558      CurrentState.AvoidBinPacking = true;
1559    else
1560      CurrentState.BreakBeforeParameter = false;
1561  }
1562  if (Current.is(TT_InheritanceColon)) {
1563    CurrentState.Indent =
1564        State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1565  }
1566  if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1567    CurrentState.NestedBlockIndent = State.Column + Current.ColumnWidth + 1;
1568  if (Current.isOneOf(TT_LambdaLSquare, TT_TrailingReturnArrow))
1569    CurrentState.LastSpace = State.Column;
1570  if (Current.is(TT_RequiresExpression) &&
1571      Style.RequiresExpressionIndentation == FormatStyle::REI_Keyword) {
1572    CurrentState.NestedBlockIndent = State.Column;
1573  }
1574
1575  // Insert scopes created by fake parenthesis.
1576  const FormatToken *Previous = Current.getPreviousNonComment();
1577
1578  // Add special behavior to support a format commonly used for JavaScript
1579  // closures:
1580  //   SomeFunction(function() {
1581  //     foo();
1582  //     bar();
1583  //   }, a, b, c);
1584  if (Current.isNot(tok::comment) && !Current.ClosesRequiresClause &&
1585      Previous && Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1586      Previous->isNot(TT_DictLiteral) && State.Stack.size() > 1 &&
1587      !CurrentState.HasMultipleNestedBlocks) {
1588    if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1589      for (ParenState &PState : llvm::drop_end(State.Stack))
1590        PState.NoLineBreak = true;
1591    State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1592  }
1593  if (Previous && (Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr) ||
1594                   (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) &&
1595                    !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)))) {
1596    CurrentState.NestedBlockInlined =
1597        !Newline && hasNestedBlockInlined(Previous, Current, Style);
1598  }
1599
1600  moveStatePastFakeLParens(State, Newline);
1601  moveStatePastScopeCloser(State);
1602  // Do not use CurrentState here, since the two functions before may change the
1603  // Stack.
1604  bool AllowBreak = !State.Stack.back().NoLineBreak &&
1605                    !State.Stack.back().NoLineBreakInOperand;
1606  moveStatePastScopeOpener(State, Newline);
1607  moveStatePastFakeRParens(State);
1608
1609  if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1610    State.StartOfStringLiteral = State.Column + 1;
1611  if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0) {
1612    State.StartOfStringLiteral = State.Column + 1;
1613  } else if (Current.is(TT_TableGenMultiLineString) &&
1614             State.StartOfStringLiteral == 0) {
1615    State.StartOfStringLiteral = State.Column + 1;
1616  } else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0) {
1617    State.StartOfStringLiteral = State.Column;
1618  } else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1619             !Current.isStringLiteral()) {
1620    State.StartOfStringLiteral = 0;
1621  }
1622
1623  State.Column += Current.ColumnWidth;
1624  State.NextToken = State.NextToken->Next;
1625  // Verilog case labels are on the same unwrapped lines as the statements that
1626  // follow. TokenAnnotator identifies them and sets MustBreakBefore.
1627  // Indentation is taken care of here. A case label can only have 1 statement
1628  // in Verilog, so we don't have to worry about lines that follow.
1629  if (Style.isVerilog() && State.NextToken &&
1630      State.NextToken->MustBreakBefore &&
1631      Keywords.isVerilogEndOfLabel(Current)) {
1632    State.FirstIndent += Style.IndentWidth;
1633    CurrentState.Indent = State.FirstIndent;
1634  }
1635
1636  unsigned Penalty =
1637      handleEndOfLine(Current, State, DryRun, AllowBreak, Newline);
1638
1639  if (Current.Role)
1640    Current.Role->formatFromToken(State, this, DryRun);
1641  // If the previous has a special role, let it consume tokens as appropriate.
1642  // It is necessary to start at the previous token for the only implemented
1643  // role (comma separated list). That way, the decision whether or not to break
1644  // after the "{" is already done and both options are tried and evaluated.
1645  // FIXME: This is ugly, find a better way.
1646  if (Previous && Previous->Role)
1647    Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1648
1649  return Penalty;
1650}
1651
1652void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1653                                                    bool Newline) {
1654  const FormatToken &Current = *State.NextToken;
1655  if (Current.FakeLParens.empty())
1656    return;
1657
1658  const FormatToken *Previous = Current.getPreviousNonComment();
1659
1660  // Don't add extra indentation for the first fake parenthesis after
1661  // 'return', assignments, opening <({[, or requires clauses. The indentation
1662  // for these cases is special cased.
1663  bool SkipFirstExtraIndent =
1664      Previous &&
1665      (Previous->opensScope() ||
1666       Previous->isOneOf(tok::semi, tok::kw_return, TT_RequiresClause) ||
1667       (Previous->getPrecedence() == prec::Assignment &&
1668        Style.AlignOperands != FormatStyle::OAS_DontAlign) ||
1669       Previous->is(TT_ObjCMethodExpr));
1670  for (const auto &PrecedenceLevel : llvm::reverse(Current.FakeLParens)) {
1671    const auto &CurrentState = State.Stack.back();
1672    ParenState NewParenState = CurrentState;
1673    NewParenState.Tok = nullptr;
1674    NewParenState.ContainsLineBreak = false;
1675    NewParenState.LastOperatorWrapped = true;
1676    NewParenState.IsChainedConditional = false;
1677    NewParenState.IsWrappedConditional = false;
1678    NewParenState.UnindentOperator = false;
1679    NewParenState.NoLineBreak =
1680        NewParenState.NoLineBreak || CurrentState.NoLineBreakInOperand;
1681
1682    // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1683    if (PrecedenceLevel > prec::Comma)
1684      NewParenState.AvoidBinPacking = false;
1685
1686    // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1687    // a builder type call after 'return' or, if the alignment after opening
1688    // brackets is disabled.
1689    if (!Current.isTrailingComment() &&
1690        (Style.AlignOperands != FormatStyle::OAS_DontAlign ||
1691         PrecedenceLevel < prec::Assignment) &&
1692        (!Previous || Previous->isNot(tok::kw_return) ||
1693         (Style.Language != FormatStyle::LK_Java && PrecedenceLevel > 0)) &&
1694        (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1695         PrecedenceLevel != prec::Comma || Current.NestingLevel == 0)) {
1696      NewParenState.Indent = std::max(
1697          std::max(State.Column, NewParenState.Indent), CurrentState.LastSpace);
1698    }
1699
1700    // Special case for generic selection expressions, its comma-separated
1701    // expressions are not aligned to the opening paren like regular calls, but
1702    // rather continuation-indented relative to the _Generic keyword.
1703    if (Previous && Previous->endsSequence(tok::l_paren, tok::kw__Generic))
1704      NewParenState.Indent = CurrentState.LastSpace;
1705
1706    if ((shouldUnindentNextOperator(Current) ||
1707         (Previous &&
1708          (PrecedenceLevel == prec::Conditional &&
1709           Previous->is(tok::question) && Previous->is(TT_ConditionalExpr)))) &&
1710        !Newline) {
1711      // If BreakBeforeBinaryOperators is set, un-indent a bit to account for
1712      // the operator and keep the operands aligned.
1713      if (Style.AlignOperands == FormatStyle::OAS_AlignAfterOperator)
1714        NewParenState.UnindentOperator = true;
1715      // Mark indentation as alignment if the expression is aligned.
1716      if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1717        NewParenState.IsAligned = true;
1718    }
1719
1720    // Do not indent relative to the fake parentheses inserted for "." or "->".
1721    // This is a special case to make the following to statements consistent:
1722    //   OuterFunction(InnerFunctionCall( // break
1723    //       ParameterToInnerFunction));
1724    //   OuterFunction(SomeObject.InnerFunctionCall( // break
1725    //       ParameterToInnerFunction));
1726    if (PrecedenceLevel > prec::Unknown)
1727      NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1728    if (PrecedenceLevel != prec::Conditional &&
1729        Current.isNot(TT_UnaryOperator) &&
1730        Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign) {
1731      NewParenState.StartOfFunctionCall = State.Column;
1732    }
1733
1734    // Indent conditional expressions, unless they are chained "else-if"
1735    // conditionals. Never indent expression where the 'operator' is ',', ';' or
1736    // an assignment (i.e. *I <= prec::Assignment) as those have different
1737    // indentation rules. Indent other expression, unless the indentation needs
1738    // to be skipped.
1739    if (PrecedenceLevel == prec::Conditional && Previous &&
1740        Previous->is(tok::colon) && Previous->is(TT_ConditionalExpr) &&
1741        &PrecedenceLevel == &Current.FakeLParens.back() &&
1742        !CurrentState.IsWrappedConditional) {
1743      NewParenState.IsChainedConditional = true;
1744      NewParenState.UnindentOperator = State.Stack.back().UnindentOperator;
1745    } else if (PrecedenceLevel == prec::Conditional ||
1746               (!SkipFirstExtraIndent && PrecedenceLevel > prec::Assignment &&
1747                !Current.isTrailingComment())) {
1748      NewParenState.Indent += Style.ContinuationIndentWidth;
1749    }
1750    if ((Previous && !Previous->opensScope()) || PrecedenceLevel != prec::Comma)
1751      NewParenState.BreakBeforeParameter = false;
1752    State.Stack.push_back(NewParenState);
1753    SkipFirstExtraIndent = false;
1754  }
1755}
1756
1757void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1758  for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1759    unsigned VariablePos = State.Stack.back().VariablePos;
1760    if (State.Stack.size() == 1) {
1761      // Do not pop the last element.
1762      break;
1763    }
1764    State.Stack.pop_back();
1765    State.Stack.back().VariablePos = VariablePos;
1766  }
1767
1768  if (State.NextToken->ClosesRequiresClause && Style.IndentRequiresClause) {
1769    // Remove the indentation of the requires clauses (which is not in Indent,
1770    // but in LastSpace).
1771    State.Stack.back().LastSpace -= Style.IndentWidth;
1772  }
1773}
1774
1775void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1776                                                    bool Newline) {
1777  const FormatToken &Current = *State.NextToken;
1778  if (!Current.opensScope())
1779    return;
1780
1781  const auto &CurrentState = State.Stack.back();
1782
1783  // Don't allow '<' or '(' in C# generic type constraints to start new scopes.
1784  if (Current.isOneOf(tok::less, tok::l_paren) &&
1785      CurrentState.IsCSharpGenericTypeConstraint) {
1786    return;
1787  }
1788
1789  if (Current.MatchingParen && Current.is(BK_Block)) {
1790    moveStateToNewBlock(State);
1791    return;
1792  }
1793
1794  unsigned NewIndent;
1795  unsigned LastSpace = CurrentState.LastSpace;
1796  bool AvoidBinPacking;
1797  bool BreakBeforeParameter = false;
1798  unsigned NestedBlockIndent = std::max(CurrentState.StartOfFunctionCall,
1799                                        CurrentState.NestedBlockIndent);
1800  if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1801      opensProtoMessageField(Current, Style)) {
1802    if (Current.opensBlockOrBlockTypeList(Style)) {
1803      NewIndent = Style.IndentWidth +
1804                  std::min(State.Column, CurrentState.NestedBlockIndent);
1805    } else if (Current.is(tok::l_brace)) {
1806      NewIndent =
1807          CurrentState.LastSpace + Style.BracedInitializerIndentWidth.value_or(
1808                                       Style.ContinuationIndentWidth);
1809    } else {
1810      NewIndent = CurrentState.LastSpace + Style.ContinuationIndentWidth;
1811    }
1812    const FormatToken *NextNonComment = Current.getNextNonComment();
1813    bool EndsInComma = Current.MatchingParen &&
1814                       Current.MatchingParen->Previous &&
1815                       Current.MatchingParen->Previous->is(tok::comma);
1816    AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1817                      Style.isProto() || !Style.BinPackArguments ||
1818                      (NextNonComment && NextNonComment->isOneOf(
1819                                             TT_DesignatedInitializerPeriod,
1820                                             TT_DesignatedInitializerLSquare));
1821    BreakBeforeParameter = EndsInComma;
1822    if (Current.ParameterCount > 1)
1823      NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1824  } else {
1825    NewIndent =
1826        Style.ContinuationIndentWidth +
1827        std::max(CurrentState.LastSpace, CurrentState.StartOfFunctionCall);
1828
1829    // Ensure that different different brackets force relative alignment, e.g.:
1830    // void SomeFunction(vector<  // break
1831    //                       int> v);
1832    // FIXME: We likely want to do this for more combinations of brackets.
1833    if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1834      NewIndent = std::max(NewIndent, CurrentState.Indent);
1835      LastSpace = std::max(LastSpace, CurrentState.Indent);
1836    }
1837
1838    bool EndsInComma =
1839        Current.MatchingParen &&
1840        Current.MatchingParen->getPreviousNonComment() &&
1841        Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1842
1843    // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1844    // for backwards compatibility.
1845    bool ObjCBinPackProtocolList =
1846        (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1847         Style.BinPackParameters) ||
1848        Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1849
1850    bool BinPackDeclaration =
1851        (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1852        (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1853
1854    bool GenericSelection =
1855        Current.getPreviousNonComment() &&
1856        Current.getPreviousNonComment()->is(tok::kw__Generic);
1857
1858    AvoidBinPacking =
1859        (CurrentState.IsCSharpGenericTypeConstraint) || GenericSelection ||
1860        (Style.isJavaScript() && EndsInComma) ||
1861        (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1862        (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1863        (Style.ExperimentalAutoDetectBinPacking &&
1864         (Current.is(PPK_OnePerLine) ||
1865          (!BinPackInconclusiveFunctions && Current.is(PPK_Inconclusive))));
1866
1867    if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen &&
1868        Style.ObjCBreakBeforeNestedBlockParam) {
1869      if (Style.ColumnLimit) {
1870        // If this '[' opens an ObjC call, determine whether all parameters fit
1871        // into one line and put one per line if they don't.
1872        if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1873            getColumnLimit(State)) {
1874          BreakBeforeParameter = true;
1875        }
1876      } else {
1877        // For ColumnLimit = 0, we have to figure out whether there is or has to
1878        // be a line break within this call.
1879        for (const FormatToken *Tok = &Current;
1880             Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1881          if (Tok->MustBreakBefore ||
1882              (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1883            BreakBeforeParameter = true;
1884            break;
1885          }
1886        }
1887      }
1888    }
1889
1890    if (Style.isJavaScript() && EndsInComma)
1891      BreakBeforeParameter = true;
1892  }
1893  // Generally inherit NoLineBreak from the current scope to nested scope.
1894  // However, don't do this for non-empty nested blocks, dict literals and
1895  // array literals as these follow different indentation rules.
1896  bool NoLineBreak =
1897      Current.Children.empty() &&
1898      !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1899      (CurrentState.NoLineBreak || CurrentState.NoLineBreakInOperand ||
1900       (Current.is(TT_TemplateOpener) &&
1901        CurrentState.ContainsUnwrappedBuilder));
1902  State.Stack.push_back(
1903      ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1904  auto &NewState = State.Stack.back();
1905  NewState.NestedBlockIndent = NestedBlockIndent;
1906  NewState.BreakBeforeParameter = BreakBeforeParameter;
1907  NewState.HasMultipleNestedBlocks = (Current.BlockParameterCount > 1);
1908
1909  if (Style.BraceWrapping.BeforeLambdaBody && Current.Next &&
1910      Current.is(tok::l_paren)) {
1911    // Search for any parameter that is a lambda.
1912    FormatToken const *next = Current.Next;
1913    while (next) {
1914      if (next->is(TT_LambdaLSquare)) {
1915        NewState.HasMultipleNestedBlocks = true;
1916        break;
1917      }
1918      next = next->Next;
1919    }
1920  }
1921
1922  NewState.IsInsideObjCArrayLiteral = Current.is(TT_ArrayInitializerLSquare) &&
1923                                      Current.Previous &&
1924                                      Current.Previous->is(tok::at);
1925}
1926
1927void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1928  const FormatToken &Current = *State.NextToken;
1929  if (!Current.closesScope())
1930    return;
1931
1932  // If we encounter a closing ), ], } or >, we can remove a level from our
1933  // stacks.
1934  if (State.Stack.size() > 1 &&
1935      (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1936       (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1937       State.NextToken->is(TT_TemplateCloser) ||
1938       (Current.is(tok::greater) && Current.is(TT_DictLiteral)))) {
1939    State.Stack.pop_back();
1940  }
1941
1942  auto &CurrentState = State.Stack.back();
1943
1944  // Reevaluate whether ObjC message arguments fit into one line.
1945  // If a receiver spans multiple lines, e.g.:
1946  //   [[object block:^{
1947  //     return 42;
1948  //   }] a:42 b:42];
1949  // BreakBeforeParameter is calculated based on an incorrect assumption
1950  // (it is checked whether the whole expression fits into one line without
1951  // considering a line break inside a message receiver).
1952  // We check whether arguments fit after receiver scope closer (into the same
1953  // line).
1954  if (CurrentState.BreakBeforeParameter && Current.MatchingParen &&
1955      Current.MatchingParen->Previous) {
1956    const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1957    if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1958        CurrentScopeOpener.MatchingParen) {
1959      int NecessarySpaceInLine =
1960          getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
1961          CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
1962      if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
1963          Style.ColumnLimit) {
1964        CurrentState.BreakBeforeParameter = false;
1965      }
1966    }
1967  }
1968
1969  if (Current.is(tok::r_square)) {
1970    // If this ends the array subscript expr, reset the corresponding value.
1971    const FormatToken *NextNonComment = Current.getNextNonComment();
1972    if (NextNonComment && NextNonComment->isNot(tok::l_square))
1973      CurrentState.StartOfArraySubscripts = 0;
1974  }
1975}
1976
1977void ContinuationIndenter::moveStateToNewBlock(LineState &State) {
1978  if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1979      State.NextToken->is(TT_LambdaLBrace) &&
1980      !State.Line->MightBeFunctionDecl) {
1981    State.Stack.back().NestedBlockIndent = State.FirstIndent;
1982  }
1983  unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
1984  // ObjC block sometimes follow special indentation rules.
1985  unsigned NewIndent =
1986      NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
1987                               ? Style.ObjCBlockIndentWidth
1988                               : Style.IndentWidth);
1989  State.Stack.push_back(ParenState(State.NextToken, NewIndent,
1990                                   State.Stack.back().LastSpace,
1991                                   /*AvoidBinPacking=*/true,
1992                                   /*NoLineBreak=*/false));
1993  State.Stack.back().NestedBlockIndent = NestedBlockIndent;
1994  State.Stack.back().BreakBeforeParameter = true;
1995}
1996
1997static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
1998                                     unsigned TabWidth,
1999                                     encoding::Encoding Encoding) {
2000  size_t LastNewlinePos = Text.find_last_of("\n");
2001  if (LastNewlinePos == StringRef::npos) {
2002    return StartColumn +
2003           encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
2004  } else {
2005    return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
2006                                         /*StartColumn=*/0, TabWidth, Encoding);
2007  }
2008}
2009
2010unsigned ContinuationIndenter::reformatRawStringLiteral(
2011    const FormatToken &Current, LineState &State,
2012    const FormatStyle &RawStringStyle, bool DryRun, bool Newline) {
2013  unsigned StartColumn = State.Column - Current.ColumnWidth;
2014  StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
2015  StringRef NewDelimiter =
2016      getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
2017  if (NewDelimiter.empty())
2018    NewDelimiter = OldDelimiter;
2019  // The text of a raw string is between the leading 'R"delimiter(' and the
2020  // trailing 'delimiter)"'.
2021  unsigned OldPrefixSize = 3 + OldDelimiter.size();
2022  unsigned OldSuffixSize = 2 + OldDelimiter.size();
2023  // We create a virtual text environment which expects a null-terminated
2024  // string, so we cannot use StringRef.
2025  std::string RawText = std::string(
2026      Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize));
2027  if (NewDelimiter != OldDelimiter) {
2028    // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
2029    // raw string.
2030    std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
2031    if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
2032      NewDelimiter = OldDelimiter;
2033  }
2034
2035  unsigned NewPrefixSize = 3 + NewDelimiter.size();
2036  unsigned NewSuffixSize = 2 + NewDelimiter.size();
2037
2038  // The first start column is the column the raw text starts after formatting.
2039  unsigned FirstStartColumn = StartColumn + NewPrefixSize;
2040
2041  // The next start column is the intended indentation a line break inside
2042  // the raw string at level 0. It is determined by the following rules:
2043  //   - if the content starts on newline, it is one level more than the current
2044  //     indent, and
2045  //   - if the content does not start on a newline, it is the first start
2046  //     column.
2047  // These rules have the advantage that the formatted content both does not
2048  // violate the rectangle rule and visually flows within the surrounding
2049  // source.
2050  bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
2051  // If this token is the last parameter (checked by looking if it's followed by
2052  // `)` and is not on a newline, the base the indent off the line's nested
2053  // block indent. Otherwise, base the indent off the arguments indent, so we
2054  // can achieve:
2055  //
2056  // fffffffffff(1, 2, 3, R"pb(
2057  //     key1: 1  #
2058  //     key2: 2)pb");
2059  //
2060  // fffffffffff(1, 2, 3,
2061  //             R"pb(
2062  //               key1: 1  #
2063  //               key2: 2
2064  //             )pb");
2065  //
2066  // fffffffffff(1, 2, 3,
2067  //             R"pb(
2068  //               key1: 1  #
2069  //               key2: 2
2070  //             )pb",
2071  //             5);
2072  unsigned CurrentIndent =
2073      (!Newline && Current.Next && Current.Next->is(tok::r_paren))
2074          ? State.Stack.back().NestedBlockIndent
2075          : State.Stack.back().Indent;
2076  unsigned NextStartColumn = ContentStartsOnNewline
2077                                 ? CurrentIndent + Style.IndentWidth
2078                                 : FirstStartColumn;
2079
2080  // The last start column is the column the raw string suffix starts if it is
2081  // put on a newline.
2082  // The last start column is the intended indentation of the raw string postfix
2083  // if it is put on a newline. It is determined by the following rules:
2084  //   - if the raw string prefix starts on a newline, it is the column where
2085  //     that raw string prefix starts, and
2086  //   - if the raw string prefix does not start on a newline, it is the current
2087  //     indent.
2088  unsigned LastStartColumn =
2089      Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent;
2090
2091  std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
2092      RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
2093      FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
2094      /*Status=*/nullptr);
2095
2096  auto NewCode = applyAllReplacements(RawText, Fixes.first);
2097  tooling::Replacements NoFixes;
2098  if (!NewCode)
2099    return addMultilineToken(Current, State);
2100  if (!DryRun) {
2101    if (NewDelimiter != OldDelimiter) {
2102      // In 'R"delimiter(...', the delimiter starts 2 characters after the start
2103      // of the token.
2104      SourceLocation PrefixDelimiterStart =
2105          Current.Tok.getLocation().getLocWithOffset(2);
2106      auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
2107          SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2108      if (PrefixErr) {
2109        llvm::errs()
2110            << "Failed to update the prefix delimiter of a raw string: "
2111            << llvm::toString(std::move(PrefixErr)) << "\n";
2112      }
2113      // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
2114      // position length - 1 - |delimiter|.
2115      SourceLocation SuffixDelimiterStart =
2116          Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
2117                                                     1 - OldDelimiter.size());
2118      auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
2119          SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2120      if (SuffixErr) {
2121        llvm::errs()
2122            << "Failed to update the suffix delimiter of a raw string: "
2123            << llvm::toString(std::move(SuffixErr)) << "\n";
2124      }
2125    }
2126    SourceLocation OriginLoc =
2127        Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
2128    for (const tooling::Replacement &Fix : Fixes.first) {
2129      auto Err = Whitespaces.addReplacement(tooling::Replacement(
2130          SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
2131          Fix.getLength(), Fix.getReplacementText()));
2132      if (Err) {
2133        llvm::errs() << "Failed to reformat raw string: "
2134                     << llvm::toString(std::move(Err)) << "\n";
2135      }
2136    }
2137  }
2138  unsigned RawLastLineEndColumn = getLastLineEndColumn(
2139      *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
2140  State.Column = RawLastLineEndColumn + NewSuffixSize;
2141  // Since we're updating the column to after the raw string literal here, we
2142  // have to manually add the penalty for the prefix R"delim( over the column
2143  // limit.
2144  unsigned PrefixExcessCharacters =
2145      StartColumn + NewPrefixSize > Style.ColumnLimit
2146          ? StartColumn + NewPrefixSize - Style.ColumnLimit
2147          : 0;
2148  bool IsMultiline =
2149      ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos);
2150  if (IsMultiline) {
2151    // Break before further function parameters on all levels.
2152    for (ParenState &Paren : State.Stack)
2153      Paren.BreakBeforeParameter = true;
2154  }
2155  return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
2156}
2157
2158unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
2159                                                 LineState &State) {
2160  // Break before further function parameters on all levels.
2161  for (ParenState &Paren : State.Stack)
2162    Paren.BreakBeforeParameter = true;
2163
2164  unsigned ColumnsUsed = State.Column;
2165  // We can only affect layout of the first and the last line, so the penalty
2166  // for all other lines is constant, and we ignore it.
2167  State.Column = Current.LastLineColumnWidth;
2168
2169  if (ColumnsUsed > getColumnLimit(State))
2170    return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
2171  return 0;
2172}
2173
2174unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
2175                                               LineState &State, bool DryRun,
2176                                               bool AllowBreak, bool Newline) {
2177  unsigned Penalty = 0;
2178  // Compute the raw string style to use in case this is a raw string literal
2179  // that can be reformatted.
2180  auto RawStringStyle = getRawStringStyle(Current, State);
2181  if (RawStringStyle && !Current.Finalized) {
2182    Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun,
2183                                       Newline);
2184  } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
2185    // Don't break multi-line tokens other than block comments and raw string
2186    // literals. Instead, just update the state.
2187    Penalty = addMultilineToken(Current, State);
2188  } else if (State.Line->Type != LT_ImportStatement) {
2189    // We generally don't break import statements.
2190    LineState OriginalState = State;
2191
2192    // Whether we force the reflowing algorithm to stay strictly within the
2193    // column limit.
2194    bool Strict = false;
2195    // Whether the first non-strict attempt at reflowing did intentionally
2196    // exceed the column limit.
2197    bool Exceeded = false;
2198    std::tie(Penalty, Exceeded) = breakProtrudingToken(
2199        Current, State, AllowBreak, /*DryRun=*/true, Strict);
2200    if (Exceeded) {
2201      // If non-strict reflowing exceeds the column limit, try whether strict
2202      // reflowing leads to an overall lower penalty.
2203      LineState StrictState = OriginalState;
2204      unsigned StrictPenalty =
2205          breakProtrudingToken(Current, StrictState, AllowBreak,
2206                               /*DryRun=*/true, /*Strict=*/true)
2207              .first;
2208      Strict = StrictPenalty <= Penalty;
2209      if (Strict) {
2210        Penalty = StrictPenalty;
2211        State = StrictState;
2212      }
2213    }
2214    if (!DryRun) {
2215      // If we're not in dry-run mode, apply the changes with the decision on
2216      // strictness made above.
2217      breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
2218                           Strict);
2219    }
2220  }
2221  if (State.Column > getColumnLimit(State)) {
2222    unsigned ExcessCharacters = State.Column - getColumnLimit(State);
2223    Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
2224  }
2225  return Penalty;
2226}
2227
2228// Returns the enclosing function name of a token, or the empty string if not
2229// found.
2230static StringRef getEnclosingFunctionName(const FormatToken &Current) {
2231  // Look for: 'function(' or 'function<templates>(' before Current.
2232  auto Tok = Current.getPreviousNonComment();
2233  if (!Tok || Tok->isNot(tok::l_paren))
2234    return "";
2235  Tok = Tok->getPreviousNonComment();
2236  if (!Tok)
2237    return "";
2238  if (Tok->is(TT_TemplateCloser)) {
2239    Tok = Tok->MatchingParen;
2240    if (Tok)
2241      Tok = Tok->getPreviousNonComment();
2242  }
2243  if (!Tok || Tok->isNot(tok::identifier))
2244    return "";
2245  return Tok->TokenText;
2246}
2247
2248std::optional<FormatStyle>
2249ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
2250                                        const LineState &State) {
2251  if (!Current.isStringLiteral())
2252    return std::nullopt;
2253  auto Delimiter = getRawStringDelimiter(Current.TokenText);
2254  if (!Delimiter)
2255    return std::nullopt;
2256  auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
2257  if (!RawStringStyle && Delimiter->empty()) {
2258    RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
2259        getEnclosingFunctionName(Current));
2260  }
2261  if (!RawStringStyle)
2262    return std::nullopt;
2263  RawStringStyle->ColumnLimit = getColumnLimit(State);
2264  return RawStringStyle;
2265}
2266
2267std::unique_ptr<BreakableToken>
2268ContinuationIndenter::createBreakableToken(const FormatToken &Current,
2269                                           LineState &State, bool AllowBreak) {
2270  unsigned StartColumn = State.Column - Current.ColumnWidth;
2271  if (Current.isStringLiteral()) {
2272    // Strings in JSON cannot be broken. Breaking strings in JavaScript is
2273    // disabled for now.
2274    if (Style.isJson() || Style.isJavaScript() || !Style.BreakStringLiterals ||
2275        !AllowBreak) {
2276      return nullptr;
2277    }
2278
2279    // Don't break string literals inside preprocessor directives (except for
2280    // #define directives, as their contents are stored in separate lines and
2281    // are not affected by this check).
2282    // This way we avoid breaking code with line directives and unknown
2283    // preprocessor directives that contain long string literals.
2284    if (State.Line->Type == LT_PreprocessorDirective)
2285      return nullptr;
2286    // Exempts unterminated string literals from line breaking. The user will
2287    // likely want to terminate the string before any line breaking is done.
2288    if (Current.IsUnterminatedLiteral)
2289      return nullptr;
2290    // Don't break string literals inside Objective-C array literals (doing so
2291    // raises the warning -Wobjc-string-concatenation).
2292    if (State.Stack.back().IsInsideObjCArrayLiteral)
2293      return nullptr;
2294
2295    // The "DPI"/"DPI-C" in SystemVerilog direct programming interface
2296    // imports/exports cannot be split, e.g.
2297    // `import "DPI" function foo();`
2298    // FIXME: make this use same infra as C++ import checks
2299    if (Style.isVerilog() && Current.Previous &&
2300        Current.Previous->isOneOf(tok::kw_export, Keywords.kw_import)) {
2301      return nullptr;
2302    }
2303    StringRef Text = Current.TokenText;
2304
2305    // We need this to address the case where there is an unbreakable tail only
2306    // if certain other formatting decisions have been taken. The
2307    // UnbreakableTailLength of Current is an overapproximation in that case and
2308    // we need to be correct here.
2309    unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
2310                                         ? 0
2311                                         : Current.UnbreakableTailLength;
2312
2313    if (Style.isVerilog() || Style.Language == FormatStyle::LK_Java ||
2314        Style.isJavaScript() || Style.isCSharp()) {
2315      BreakableStringLiteralUsingOperators::QuoteStyleType QuoteStyle;
2316      if (Style.isJavaScript() && Text.starts_with("'") &&
2317          Text.ends_with("'")) {
2318        QuoteStyle = BreakableStringLiteralUsingOperators::SingleQuotes;
2319      } else if (Style.isCSharp() && Text.starts_with("@\"") &&
2320                 Text.ends_with("\"")) {
2321        QuoteStyle = BreakableStringLiteralUsingOperators::AtDoubleQuotes;
2322      } else if (Text.starts_with("\"") && Text.ends_with("\"")) {
2323        QuoteStyle = BreakableStringLiteralUsingOperators::DoubleQuotes;
2324      } else {
2325        return nullptr;
2326      }
2327      return std::make_unique<BreakableStringLiteralUsingOperators>(
2328          Current, QuoteStyle,
2329          /*UnindentPlus=*/shouldUnindentNextOperator(Current), StartColumn,
2330          UnbreakableTailLength, State.Line->InPPDirective, Encoding, Style);
2331    }
2332
2333    StringRef Prefix;
2334    StringRef Postfix;
2335    // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
2336    // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
2337    // reduce the overhead) for each FormatToken, which is a string, so that we
2338    // don't run multiple checks here on the hot path.
2339    if ((Text.ends_with(Postfix = "\"") &&
2340         (Text.starts_with(Prefix = "@\"") || Text.starts_with(Prefix = "\"") ||
2341          Text.starts_with(Prefix = "u\"") ||
2342          Text.starts_with(Prefix = "U\"") ||
2343          Text.starts_with(Prefix = "u8\"") ||
2344          Text.starts_with(Prefix = "L\""))) ||
2345        (Text.starts_with(Prefix = "_T(\"") &&
2346         Text.ends_with(Postfix = "\")"))) {
2347      return std::make_unique<BreakableStringLiteral>(
2348          Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
2349          State.Line->InPPDirective, Encoding, Style);
2350    }
2351  } else if (Current.is(TT_BlockComment)) {
2352    if (!Style.ReflowComments ||
2353        // If a comment token switches formatting, like
2354        // /* clang-format on */, we don't want to break it further,
2355        // but we may still want to adjust its indentation.
2356        switchesFormatting(Current)) {
2357      return nullptr;
2358    }
2359    return std::make_unique<BreakableBlockComment>(
2360        Current, StartColumn, Current.OriginalColumn, !Current.Previous,
2361        State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF());
2362  } else if (Current.is(TT_LineComment) &&
2363             (!Current.Previous ||
2364              Current.Previous->isNot(TT_ImplicitStringLiteral))) {
2365    bool RegularComments = [&]() {
2366      for (const FormatToken *T = &Current; T && T->is(TT_LineComment);
2367           T = T->Next) {
2368        if (!(T->TokenText.starts_with("//") || T->TokenText.starts_with("#")))
2369          return false;
2370      }
2371      return true;
2372    }();
2373    if (!Style.ReflowComments ||
2374        CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
2375        switchesFormatting(Current) || !RegularComments) {
2376      return nullptr;
2377    }
2378    return std::make_unique<BreakableLineCommentSection>(
2379        Current, StartColumn, /*InPPDirective=*/false, Encoding, Style);
2380  }
2381  return nullptr;
2382}
2383
2384std::pair<unsigned, bool>
2385ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
2386                                           LineState &State, bool AllowBreak,
2387                                           bool DryRun, bool Strict) {
2388  std::unique_ptr<const BreakableToken> Token =
2389      createBreakableToken(Current, State, AllowBreak);
2390  if (!Token)
2391    return {0, false};
2392  assert(Token->getLineCount() > 0);
2393  unsigned ColumnLimit = getColumnLimit(State);
2394  if (Current.is(TT_LineComment)) {
2395    // We don't insert backslashes when breaking line comments.
2396    ColumnLimit = Style.ColumnLimit;
2397  }
2398  if (ColumnLimit == 0) {
2399    // To make the rest of the function easier set the column limit to the
2400    // maximum, if there should be no limit.
2401    ColumnLimit = std::numeric_limits<decltype(ColumnLimit)>::max();
2402  }
2403  if (Current.UnbreakableTailLength >= ColumnLimit)
2404    return {0, false};
2405  // ColumnWidth was already accounted into State.Column before calling
2406  // breakProtrudingToken.
2407  unsigned StartColumn = State.Column - Current.ColumnWidth;
2408  unsigned NewBreakPenalty = Current.isStringLiteral()
2409                                 ? Style.PenaltyBreakString
2410                                 : Style.PenaltyBreakComment;
2411  // Stores whether we intentionally decide to let a line exceed the column
2412  // limit.
2413  bool Exceeded = false;
2414  // Stores whether we introduce a break anywhere in the token.
2415  bool BreakInserted = Token->introducesBreakBeforeToken();
2416  // Store whether we inserted a new line break at the end of the previous
2417  // logical line.
2418  bool NewBreakBefore = false;
2419  // We use a conservative reflowing strategy. Reflow starts after a line is
2420  // broken or the corresponding whitespace compressed. Reflow ends as soon as a
2421  // line that doesn't get reflown with the previous line is reached.
2422  bool Reflow = false;
2423  // Keep track of where we are in the token:
2424  // Where we are in the content of the current logical line.
2425  unsigned TailOffset = 0;
2426  // The column number we're currently at.
2427  unsigned ContentStartColumn =
2428      Token->getContentStartColumn(0, /*Break=*/false);
2429  // The number of columns left in the current logical line after TailOffset.
2430  unsigned RemainingTokenColumns =
2431      Token->getRemainingLength(0, TailOffset, ContentStartColumn);
2432  // Adapt the start of the token, for example indent.
2433  if (!DryRun)
2434    Token->adaptStartOfLine(0, Whitespaces);
2435
2436  unsigned ContentIndent = 0;
2437  unsigned Penalty = 0;
2438  LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
2439                          << StartColumn << ".\n");
2440  for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
2441       LineIndex != EndIndex; ++LineIndex) {
2442    LLVM_DEBUG(llvm::dbgs()
2443               << "  Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
2444    NewBreakBefore = false;
2445    // If we did reflow the previous line, we'll try reflowing again. Otherwise
2446    // we'll start reflowing if the current line is broken or whitespace is
2447    // compressed.
2448    bool TryReflow = Reflow;
2449    // Break the current token until we can fit the rest of the line.
2450    while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2451      LLVM_DEBUG(llvm::dbgs() << "    Over limit, need: "
2452                              << (ContentStartColumn + RemainingTokenColumns)
2453                              << ", space: " << ColumnLimit
2454                              << ", reflown prefix: " << ContentStartColumn
2455                              << ", offset in line: " << TailOffset << "\n");
2456      // If the current token doesn't fit, find the latest possible split in the
2457      // current line so that breaking at it will be under the column limit.
2458      // FIXME: Use the earliest possible split while reflowing to correctly
2459      // compress whitespace within a line.
2460      BreakableToken::Split Split =
2461          Token->getSplit(LineIndex, TailOffset, ColumnLimit,
2462                          ContentStartColumn, CommentPragmasRegex);
2463      if (Split.first == StringRef::npos) {
2464        // No break opportunity - update the penalty and continue with the next
2465        // logical line.
2466        if (LineIndex < EndIndex - 1) {
2467          // The last line's penalty is handled in addNextStateToQueue() or when
2468          // calling replaceWhitespaceAfterLastLine below.
2469          Penalty += Style.PenaltyExcessCharacter *
2470                     (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2471        }
2472        LLVM_DEBUG(llvm::dbgs() << "    No break opportunity.\n");
2473        break;
2474      }
2475      assert(Split.first != 0);
2476
2477      if (Token->supportsReflow()) {
2478        // Check whether the next natural split point after the current one can
2479        // still fit the line, either because we can compress away whitespace,
2480        // or because the penalty the excess characters introduce is lower than
2481        // the break penalty.
2482        // We only do this for tokens that support reflowing, and thus allow us
2483        // to change the whitespace arbitrarily (e.g. comments).
2484        // Other tokens, like string literals, can be broken on arbitrary
2485        // positions.
2486
2487        // First, compute the columns from TailOffset to the next possible split
2488        // position.
2489        // For example:
2490        // ColumnLimit:     |
2491        // // Some text   that    breaks
2492        //    ^ tail offset
2493        //             ^-- split
2494        //    ^-------- to split columns
2495        //                    ^--- next split
2496        //    ^--------------- to next split columns
2497        unsigned ToSplitColumns = Token->getRangeLength(
2498            LineIndex, TailOffset, Split.first, ContentStartColumn);
2499        LLVM_DEBUG(llvm::dbgs() << "    ToSplit: " << ToSplitColumns << "\n");
2500
2501        BreakableToken::Split NextSplit = Token->getSplit(
2502            LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
2503            ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
2504        // Compute the columns necessary to fit the next non-breakable sequence
2505        // into the current line.
2506        unsigned ToNextSplitColumns = 0;
2507        if (NextSplit.first == StringRef::npos) {
2508          ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
2509                                                         ContentStartColumn);
2510        } else {
2511          ToNextSplitColumns = Token->getRangeLength(
2512              LineIndex, TailOffset,
2513              Split.first + Split.second + NextSplit.first, ContentStartColumn);
2514        }
2515        // Compress the whitespace between the break and the start of the next
2516        // unbreakable sequence.
2517        ToNextSplitColumns =
2518            Token->getLengthAfterCompression(ToNextSplitColumns, Split);
2519        LLVM_DEBUG(llvm::dbgs()
2520                   << "    ContentStartColumn: " << ContentStartColumn << "\n");
2521        LLVM_DEBUG(llvm::dbgs()
2522                   << "    ToNextSplit: " << ToNextSplitColumns << "\n");
2523        // If the whitespace compression makes us fit, continue on the current
2524        // line.
2525        bool ContinueOnLine =
2526            ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
2527        unsigned ExcessCharactersPenalty = 0;
2528        if (!ContinueOnLine && !Strict) {
2529          // Similarly, if the excess characters' penalty is lower than the
2530          // penalty of introducing a new break, continue on the current line.
2531          ExcessCharactersPenalty =
2532              (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
2533              Style.PenaltyExcessCharacter;
2534          LLVM_DEBUG(llvm::dbgs()
2535                     << "    Penalty excess: " << ExcessCharactersPenalty
2536                     << "\n            break : " << NewBreakPenalty << "\n");
2537          if (ExcessCharactersPenalty < NewBreakPenalty) {
2538            Exceeded = true;
2539            ContinueOnLine = true;
2540          }
2541        }
2542        if (ContinueOnLine) {
2543          LLVM_DEBUG(llvm::dbgs() << "    Continuing on line...\n");
2544          // The current line fits after compressing the whitespace - reflow
2545          // the next line into it if possible.
2546          TryReflow = true;
2547          if (!DryRun) {
2548            Token->compressWhitespace(LineIndex, TailOffset, Split,
2549                                      Whitespaces);
2550          }
2551          // When we continue on the same line, leave one space between content.
2552          ContentStartColumn += ToSplitColumns + 1;
2553          Penalty += ExcessCharactersPenalty;
2554          TailOffset += Split.first + Split.second;
2555          RemainingTokenColumns = Token->getRemainingLength(
2556              LineIndex, TailOffset, ContentStartColumn);
2557          continue;
2558        }
2559      }
2560      LLVM_DEBUG(llvm::dbgs() << "    Breaking...\n");
2561      // Update the ContentIndent only if the current line was not reflown with
2562      // the previous line, since in that case the previous line should still
2563      // determine the ContentIndent. Also never intent the last line.
2564      if (!Reflow)
2565        ContentIndent = Token->getContentIndent(LineIndex);
2566      LLVM_DEBUG(llvm::dbgs()
2567                 << "    ContentIndent: " << ContentIndent << "\n");
2568      ContentStartColumn = ContentIndent + Token->getContentStartColumn(
2569                                               LineIndex, /*Break=*/true);
2570
2571      unsigned NewRemainingTokenColumns = Token->getRemainingLength(
2572          LineIndex, TailOffset + Split.first + Split.second,
2573          ContentStartColumn);
2574      if (NewRemainingTokenColumns == 0) {
2575        // No content to indent.
2576        ContentIndent = 0;
2577        ContentStartColumn =
2578            Token->getContentStartColumn(LineIndex, /*Break=*/true);
2579        NewRemainingTokenColumns = Token->getRemainingLength(
2580            LineIndex, TailOffset + Split.first + Split.second,
2581            ContentStartColumn);
2582      }
2583
2584      // When breaking before a tab character, it may be moved by a few columns,
2585      // but will still be expanded to the next tab stop, so we don't save any
2586      // columns.
2587      if (NewRemainingTokenColumns >= RemainingTokenColumns) {
2588        // FIXME: Do we need to adjust the penalty?
2589        break;
2590      }
2591
2592      LLVM_DEBUG(llvm::dbgs() << "    Breaking at: " << TailOffset + Split.first
2593                              << ", " << Split.second << "\n");
2594      if (!DryRun) {
2595        Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
2596                           Whitespaces);
2597      }
2598
2599      Penalty += NewBreakPenalty;
2600      TailOffset += Split.first + Split.second;
2601      RemainingTokenColumns = NewRemainingTokenColumns;
2602      BreakInserted = true;
2603      NewBreakBefore = true;
2604    }
2605    // In case there's another line, prepare the state for the start of the next
2606    // line.
2607    if (LineIndex + 1 != EndIndex) {
2608      unsigned NextLineIndex = LineIndex + 1;
2609      if (NewBreakBefore) {
2610        // After breaking a line, try to reflow the next line into the current
2611        // one once RemainingTokenColumns fits.
2612        TryReflow = true;
2613      }
2614      if (TryReflow) {
2615        // We decided that we want to try reflowing the next line into the
2616        // current one.
2617        // We will now adjust the state as if the reflow is successful (in
2618        // preparation for the next line), and see whether that works. If we
2619        // decide that we cannot reflow, we will later reset the state to the
2620        // start of the next line.
2621        Reflow = false;
2622        // As we did not continue breaking the line, RemainingTokenColumns is
2623        // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2624        // the position at which we want to format the next line if we do
2625        // actually reflow.
2626        // When we reflow, we need to add a space between the end of the current
2627        // line and the next line's start column.
2628        ContentStartColumn += RemainingTokenColumns + 1;
2629        // Get the split that we need to reflow next logical line into the end
2630        // of the current one; the split will include any leading whitespace of
2631        // the next logical line.
2632        BreakableToken::Split SplitBeforeNext =
2633            Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2634        LLVM_DEBUG(llvm::dbgs()
2635                   << "    Size of reflown text: " << ContentStartColumn
2636                   << "\n    Potential reflow split: ");
2637        if (SplitBeforeNext.first != StringRef::npos) {
2638          LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2639                                  << SplitBeforeNext.second << "\n");
2640          TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2641          // If the rest of the next line fits into the current line below the
2642          // column limit, we can safely reflow.
2643          RemainingTokenColumns = Token->getRemainingLength(
2644              NextLineIndex, TailOffset, ContentStartColumn);
2645          Reflow = true;
2646          if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2647            LLVM_DEBUG(llvm::dbgs()
2648                       << "    Over limit after reflow, need: "
2649                       << (ContentStartColumn + RemainingTokenColumns)
2650                       << ", space: " << ColumnLimit
2651                       << ", reflown prefix: " << ContentStartColumn
2652                       << ", offset in line: " << TailOffset << "\n");
2653            // If the whole next line does not fit, try to find a point in
2654            // the next line at which we can break so that attaching the part
2655            // of the next line to that break point onto the current line is
2656            // below the column limit.
2657            BreakableToken::Split Split =
2658                Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2659                                ContentStartColumn, CommentPragmasRegex);
2660            if (Split.first == StringRef::npos) {
2661              LLVM_DEBUG(llvm::dbgs() << "    Did not find later break\n");
2662              Reflow = false;
2663            } else {
2664              // Check whether the first split point gets us below the column
2665              // limit. Note that we will execute this split below as part of
2666              // the normal token breaking and reflow logic within the line.
2667              unsigned ToSplitColumns = Token->getRangeLength(
2668                  NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2669              if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2670                LLVM_DEBUG(llvm::dbgs() << "    Next split protrudes, need: "
2671                                        << (ContentStartColumn + ToSplitColumns)
2672                                        << ", space: " << ColumnLimit);
2673                unsigned ExcessCharactersPenalty =
2674                    (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2675                    Style.PenaltyExcessCharacter;
2676                if (NewBreakPenalty < ExcessCharactersPenalty)
2677                  Reflow = false;
2678              }
2679            }
2680          }
2681        } else {
2682          LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2683        }
2684      }
2685      if (!Reflow) {
2686        // If we didn't reflow into the next line, the only space to consider is
2687        // the next logical line. Reset our state to match the start of the next
2688        // line.
2689        TailOffset = 0;
2690        ContentStartColumn =
2691            Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2692        RemainingTokenColumns = Token->getRemainingLength(
2693            NextLineIndex, TailOffset, ContentStartColumn);
2694        // Adapt the start of the token, for example indent.
2695        if (!DryRun)
2696          Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2697      } else {
2698        // If we found a reflow split and have added a new break before the next
2699        // line, we are going to remove the line break at the start of the next
2700        // logical line. For example, here we'll add a new line break after
2701        // 'text', and subsequently delete the line break between 'that' and
2702        // 'reflows'.
2703        //   // some text that
2704        //   // reflows
2705        // ->
2706        //   // some text
2707        //   // that reflows
2708        // When adding the line break, we also added the penalty for it, so we
2709        // need to subtract that penalty again when we remove the line break due
2710        // to reflowing.
2711        if (NewBreakBefore) {
2712          assert(Penalty >= NewBreakPenalty);
2713          Penalty -= NewBreakPenalty;
2714        }
2715        if (!DryRun)
2716          Token->reflow(NextLineIndex, Whitespaces);
2717      }
2718    }
2719  }
2720
2721  BreakableToken::Split SplitAfterLastLine =
2722      Token->getSplitAfterLastLine(TailOffset);
2723  if (SplitAfterLastLine.first != StringRef::npos) {
2724    LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2725
2726    // We add the last line's penalty here, since that line is going to be split
2727    // now.
2728    Penalty += Style.PenaltyExcessCharacter *
2729               (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2730
2731    if (!DryRun) {
2732      Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2733                                            Whitespaces);
2734    }
2735    ContentStartColumn =
2736        Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2737    RemainingTokenColumns = Token->getRemainingLength(
2738        Token->getLineCount() - 1,
2739        TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2740        ContentStartColumn);
2741  }
2742
2743  State.Column = ContentStartColumn + RemainingTokenColumns -
2744                 Current.UnbreakableTailLength;
2745
2746  if (BreakInserted) {
2747    if (!DryRun)
2748      Token->updateAfterBroken(Whitespaces);
2749
2750    // If we break the token inside a parameter list, we need to break before
2751    // the next parameter on all levels, so that the next parameter is clearly
2752    // visible. Line comments already introduce a break.
2753    if (Current.isNot(TT_LineComment))
2754      for (ParenState &Paren : State.Stack)
2755        Paren.BreakBeforeParameter = true;
2756
2757    if (Current.is(TT_BlockComment))
2758      State.NoContinuation = true;
2759
2760    State.Stack.back().LastSpace = StartColumn;
2761  }
2762
2763  Token->updateNextToken(State);
2764
2765  return {Penalty, Exceeded};
2766}
2767
2768unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2769  // In preprocessor directives reserve two chars for trailing " \".
2770  return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2771}
2772
2773bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2774  const FormatToken &Current = *State.NextToken;
2775  if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2776    return false;
2777  // We never consider raw string literals "multiline" for the purpose of
2778  // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2779  // (see TokenAnnotator::mustBreakBefore().
2780  if (Current.TokenText.starts_with("R\""))
2781    return false;
2782  if (Current.IsMultiline)
2783    return true;
2784  if (Current.getNextNonComment() &&
2785      Current.getNextNonComment()->isStringLiteral()) {
2786    return true; // Implicit concatenation.
2787  }
2788  if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2789      State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2790          Style.ColumnLimit) {
2791    return true; // String will be split.
2792  }
2793  return false;
2794}
2795
2796} // namespace format
2797} // namespace clang
2798