1 //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file implements the continuation indenter.
11 ///
12 //===----------------------------------------------------------------------===//
13
14 #include "ContinuationIndenter.h"
15 #include "BreakableToken.h"
16 #include "FormatInternal.h"
17 #include "FormatToken.h"
18 #include "WhitespaceManager.h"
19 #include "clang/Basic/OperatorPrecedence.h"
20 #include "clang/Basic/SourceManager.h"
21 #include "clang/Basic/TokenKinds.h"
22 #include "clang/Format/Format.h"
23 #include "llvm/ADT/StringSet.h"
24 #include "llvm/Support/Debug.h"
25 #include <optional>
26
27 #define DEBUG_TYPE "format-indenter"
28
29 namespace clang {
30 namespace format {
31
32 // Returns true if a TT_SelectorName should be indented when wrapped,
33 // false otherwise.
shouldIndentWrappedSelectorName(const FormatStyle & Style,LineType LineType)34 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style,
35 LineType LineType) {
36 return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl;
37 }
38
39 // Returns true if a binary operator following \p Tok should be unindented when
40 // the style permits it.
shouldUnindentNextOperator(const FormatToken & Tok)41 static bool shouldUnindentNextOperator(const FormatToken &Tok) {
42 const FormatToken *Previous = Tok.getPreviousNonComment();
43 return Previous && (Previous->getPrecedence() == prec::Assignment ||
44 Previous->isOneOf(tok::kw_return, TT_RequiresClause));
45 }
46
47 // Returns the length of everything up to the first possible line break after
48 // the ), ], } or > matching \c Tok.
getLengthToMatchingParen(const FormatToken & Tok,ArrayRef<ParenState> Stack)49 static unsigned getLengthToMatchingParen(const FormatToken &Tok,
50 ArrayRef<ParenState> Stack) {
51 // Normally whether or not a break before T is possible is calculated and
52 // stored in T.CanBreakBefore. Braces, array initializers and text proto
53 // messages like `key: < ... >` are an exception: a break is possible
54 // before a closing brace R if a break was inserted after the corresponding
55 // opening brace. The information about whether or not a break is needed
56 // before a closing brace R is stored in the ParenState field
57 // S.BreakBeforeClosingBrace where S is the state that R closes.
58 //
59 // In order to decide whether there can be a break before encountered right
60 // braces, this implementation iterates over the sequence of tokens and over
61 // the paren stack in lockstep, keeping track of the stack level which visited
62 // right braces correspond to in MatchingStackIndex.
63 //
64 // For example, consider:
65 // L. <- line number
66 // 1. {
67 // 2. {1},
68 // 3. {2},
69 // 4. {{3}}}
70 // ^ where we call this method with this token.
71 // The paren stack at this point contains 3 brace levels:
72 // 0. { at line 1, BreakBeforeClosingBrace: true
73 // 1. first { at line 4, BreakBeforeClosingBrace: false
74 // 2. second { at line 4, BreakBeforeClosingBrace: false,
75 // where there might be fake parens levels in-between these levels.
76 // The algorithm will start at the first } on line 4, which is the matching
77 // brace of the initial left brace and at level 2 of the stack. Then,
78 // examining BreakBeforeClosingBrace: false at level 2, it will continue to
79 // the second } on line 4, and will traverse the stack downwards until it
80 // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace:
81 // false at level 1, it will continue to the third } on line 4 and will
82 // traverse the stack downwards until it finds the matching { on level 0.
83 // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm
84 // will stop and will use the second } on line 4 to determine the length to
85 // return, as in this example the range will include the tokens: {3}}
86 //
87 // The algorithm will only traverse the stack if it encounters braces, array
88 // initializer squares or text proto angle brackets.
89 if (!Tok.MatchingParen)
90 return 0;
91 FormatToken *End = Tok.MatchingParen;
92 // Maintains a stack level corresponding to the current End token.
93 int MatchingStackIndex = Stack.size() - 1;
94 // Traverses the stack downwards, looking for the level to which LBrace
95 // corresponds. Returns either a pointer to the matching level or nullptr if
96 // LParen is not found in the initial portion of the stack up to
97 // MatchingStackIndex.
98 auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * {
99 while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace)
100 --MatchingStackIndex;
101 return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr;
102 };
103 for (; End->Next; End = End->Next) {
104 if (End->Next->CanBreakBefore)
105 break;
106 if (!End->Next->closesScope())
107 continue;
108 if (End->Next->MatchingParen &&
109 End->Next->MatchingParen->isOneOf(
110 tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) {
111 const ParenState *State = FindParenState(End->Next->MatchingParen);
112 if (State && State->BreakBeforeClosingBrace)
113 break;
114 }
115 }
116 return End->TotalLength - Tok.TotalLength + 1;
117 }
118
getLengthToNextOperator(const FormatToken & Tok)119 static unsigned getLengthToNextOperator(const FormatToken &Tok) {
120 if (!Tok.NextOperator)
121 return 0;
122 return Tok.NextOperator->TotalLength - Tok.TotalLength;
123 }
124
125 // Returns \c true if \c Tok is the "." or "->" of a call and starts the next
126 // segment of a builder type call.
startsSegmentOfBuilderTypeCall(const FormatToken & Tok)127 static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) {
128 return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope();
129 }
130
131 // Returns \c true if \c Current starts a new parameter.
startsNextParameter(const FormatToken & Current,const FormatStyle & Style)132 static bool startsNextParameter(const FormatToken &Current,
133 const FormatStyle &Style) {
134 const FormatToken &Previous = *Current.Previous;
135 if (Current.is(TT_CtorInitializerComma) &&
136 Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma) {
137 return true;
138 }
139 if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName))
140 return true;
141 return Previous.is(tok::comma) && !Current.isTrailingComment() &&
142 ((Previous.isNot(TT_CtorInitializerComma) ||
143 Style.BreakConstructorInitializers !=
144 FormatStyle::BCIS_BeforeComma) &&
145 (Previous.isNot(TT_InheritanceComma) ||
146 Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma));
147 }
148
opensProtoMessageField(const FormatToken & LessTok,const FormatStyle & Style)149 static bool opensProtoMessageField(const FormatToken &LessTok,
150 const FormatStyle &Style) {
151 if (LessTok.isNot(tok::less))
152 return false;
153 return Style.Language == FormatStyle::LK_TextProto ||
154 (Style.Language == FormatStyle::LK_Proto &&
155 (LessTok.NestingLevel > 0 ||
156 (LessTok.Previous && LessTok.Previous->is(tok::equal))));
157 }
158
159 // Returns the delimiter of a raw string literal, or std::nullopt if TokenText
160 // is not the text of a raw string literal. The delimiter could be the empty
161 // string. For example, the delimiter of R"deli(cont)deli" is deli.
getRawStringDelimiter(StringRef TokenText)162 static std::optional<StringRef> getRawStringDelimiter(StringRef TokenText) {
163 if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'.
164 || !TokenText.starts_with("R\"") || !TokenText.ends_with("\"")) {
165 return std::nullopt;
166 }
167
168 // A raw string starts with 'R"<delimiter>(' and delimiter is ascii and has
169 // size at most 16 by the standard, so the first '(' must be among the first
170 // 19 bytes.
171 size_t LParenPos = TokenText.substr(0, 19).find_first_of('(');
172 if (LParenPos == StringRef::npos)
173 return std::nullopt;
174 StringRef Delimiter = TokenText.substr(2, LParenPos - 2);
175
176 // Check that the string ends in ')Delimiter"'.
177 size_t RParenPos = TokenText.size() - Delimiter.size() - 2;
178 if (TokenText[RParenPos] != ')')
179 return std::nullopt;
180 if (!TokenText.substr(RParenPos + 1).starts_with(Delimiter))
181 return std::nullopt;
182 return Delimiter;
183 }
184
185 // Returns the canonical delimiter for \p Language, or the empty string if no
186 // canonical delimiter is specified.
187 static StringRef
getCanonicalRawStringDelimiter(const FormatStyle & Style,FormatStyle::LanguageKind Language)188 getCanonicalRawStringDelimiter(const FormatStyle &Style,
189 FormatStyle::LanguageKind Language) {
190 for (const auto &Format : Style.RawStringFormats)
191 if (Format.Language == Language)
192 return StringRef(Format.CanonicalDelimiter);
193 return "";
194 }
195
RawStringFormatStyleManager(const FormatStyle & CodeStyle)196 RawStringFormatStyleManager::RawStringFormatStyleManager(
197 const FormatStyle &CodeStyle) {
198 for (const auto &RawStringFormat : CodeStyle.RawStringFormats) {
199 std::optional<FormatStyle> LanguageStyle =
200 CodeStyle.GetLanguageStyle(RawStringFormat.Language);
201 if (!LanguageStyle) {
202 FormatStyle PredefinedStyle;
203 if (!getPredefinedStyle(RawStringFormat.BasedOnStyle,
204 RawStringFormat.Language, &PredefinedStyle)) {
205 PredefinedStyle = getLLVMStyle();
206 PredefinedStyle.Language = RawStringFormat.Language;
207 }
208 LanguageStyle = PredefinedStyle;
209 }
210 LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit;
211 for (StringRef Delimiter : RawStringFormat.Delimiters)
212 DelimiterStyle.insert({Delimiter, *LanguageStyle});
213 for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions)
214 EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle});
215 }
216 }
217
218 std::optional<FormatStyle>
getDelimiterStyle(StringRef Delimiter) const219 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const {
220 auto It = DelimiterStyle.find(Delimiter);
221 if (It == DelimiterStyle.end())
222 return std::nullopt;
223 return It->second;
224 }
225
226 std::optional<FormatStyle>
getEnclosingFunctionStyle(StringRef EnclosingFunction) const227 RawStringFormatStyleManager::getEnclosingFunctionStyle(
228 StringRef EnclosingFunction) const {
229 auto It = EnclosingFunctionStyle.find(EnclosingFunction);
230 if (It == EnclosingFunctionStyle.end())
231 return std::nullopt;
232 return It->second;
233 }
234
ContinuationIndenter(const FormatStyle & Style,const AdditionalKeywords & Keywords,const SourceManager & SourceMgr,WhitespaceManager & Whitespaces,encoding::Encoding Encoding,bool BinPackInconclusiveFunctions)235 ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style,
236 const AdditionalKeywords &Keywords,
237 const SourceManager &SourceMgr,
238 WhitespaceManager &Whitespaces,
239 encoding::Encoding Encoding,
240 bool BinPackInconclusiveFunctions)
241 : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr),
242 Whitespaces(Whitespaces), Encoding(Encoding),
243 BinPackInconclusiveFunctions(BinPackInconclusiveFunctions),
244 CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {}
245
getInitialState(unsigned FirstIndent,unsigned FirstStartColumn,const AnnotatedLine * Line,bool DryRun)246 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent,
247 unsigned FirstStartColumn,
248 const AnnotatedLine *Line,
249 bool DryRun) {
250 LineState State;
251 State.FirstIndent = FirstIndent;
252 if (FirstStartColumn && Line->First->NewlinesBefore == 0)
253 State.Column = FirstStartColumn;
254 else
255 State.Column = FirstIndent;
256 // With preprocessor directive indentation, the line starts on column 0
257 // since it's indented after the hash, but FirstIndent is set to the
258 // preprocessor indent.
259 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
260 (Line->Type == LT_PreprocessorDirective ||
261 Line->Type == LT_ImportStatement)) {
262 State.Column = 0;
263 }
264 State.Line = Line;
265 State.NextToken = Line->First;
266 State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent,
267 /*AvoidBinPacking=*/false,
268 /*NoLineBreak=*/false));
269 State.NoContinuation = false;
270 State.StartOfStringLiteral = 0;
271 State.NoLineBreak = false;
272 State.StartOfLineLevel = 0;
273 State.LowestLevelOnLine = 0;
274 State.IgnoreStackForComparison = false;
275
276 if (Style.Language == FormatStyle::LK_TextProto) {
277 // We need this in order to deal with the bin packing of text fields at
278 // global scope.
279 auto &CurrentState = State.Stack.back();
280 CurrentState.AvoidBinPacking = true;
281 CurrentState.BreakBeforeParameter = true;
282 CurrentState.AlignColons = false;
283 }
284
285 // The first token has already been indented and thus consumed.
286 moveStateToNextToken(State, DryRun, /*Newline=*/false);
287 return State;
288 }
289
canBreak(const LineState & State)290 bool ContinuationIndenter::canBreak(const LineState &State) {
291 const FormatToken &Current = *State.NextToken;
292 const FormatToken &Previous = *Current.Previous;
293 const auto &CurrentState = State.Stack.back();
294 assert(&Previous == Current.Previous);
295 if (!Current.CanBreakBefore && !(CurrentState.BreakBeforeClosingBrace &&
296 Current.closesBlockOrBlockTypeList(Style))) {
297 return false;
298 }
299 // The opening "{" of a braced list has to be on the same line as the first
300 // element if it is nested in another braced init list or function call.
301 if (!Current.MustBreakBefore && Previous.is(tok::l_brace) &&
302 Previous.isNot(TT_DictLiteral) && Previous.is(BK_BracedInit) &&
303 Previous.Previous &&
304 Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma)) {
305 return false;
306 }
307 // This prevents breaks like:
308 // ...
309 // SomeParameter, OtherParameter).DoSomething(
310 // ...
311 // As they hide "DoSomething" and are generally bad for readability.
312 if (Previous.opensScope() && Previous.isNot(tok::l_brace) &&
313 State.LowestLevelOnLine < State.StartOfLineLevel &&
314 State.LowestLevelOnLine < Current.NestingLevel) {
315 return false;
316 }
317 if (Current.isMemberAccess() && CurrentState.ContainsUnwrappedBuilder)
318 return false;
319
320 // Don't create a 'hanging' indent if there are multiple blocks in a single
321 // statement and we are aligning lambda blocks to their signatures.
322 if (Previous.is(tok::l_brace) && State.Stack.size() > 1 &&
323 State.Stack[State.Stack.size() - 2].NestedBlockInlined &&
324 State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks &&
325 Style.LambdaBodyIndentation == FormatStyle::LBI_Signature) {
326 return false;
327 }
328
329 // Don't break after very short return types (e.g. "void") as that is often
330 // unexpected.
331 if (Current.is(TT_FunctionDeclarationName)) {
332 if (Style.BreakAfterReturnType == FormatStyle::RTBS_None &&
333 State.Column < 6) {
334 return false;
335 }
336
337 if (Style.BreakAfterReturnType == FormatStyle::RTBS_ExceptShortType) {
338 assert(State.Column >= State.FirstIndent);
339 if (State.Column - State.FirstIndent < 6)
340 return false;
341 }
342 }
343
344 // If binary operators are moved to the next line (including commas for some
345 // styles of constructor initializers), that's always ok.
346 if (!Current.isOneOf(TT_BinaryOperator, tok::comma) &&
347 // Allow breaking opening brace of lambdas (when passed as function
348 // arguments) to a new line when BeforeLambdaBody brace wrapping is
349 // enabled.
350 (!Style.BraceWrapping.BeforeLambdaBody ||
351 Current.isNot(TT_LambdaLBrace)) &&
352 CurrentState.NoLineBreakInOperand) {
353 return false;
354 }
355
356 if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr))
357 return false;
358
359 if (Current.is(TT_ConditionalExpr) && Previous.is(tok::r_paren) &&
360 Previous.MatchingParen && Previous.MatchingParen->Previous &&
361 Previous.MatchingParen->Previous->MatchingParen &&
362 Previous.MatchingParen->Previous->MatchingParen->is(TT_LambdaLBrace)) {
363 // We have a lambda within a conditional expression, allow breaking here.
364 assert(Previous.MatchingParen->Previous->is(tok::r_brace));
365 return true;
366 }
367
368 return !State.NoLineBreak && !CurrentState.NoLineBreak;
369 }
370
mustBreak(const LineState & State)371 bool ContinuationIndenter::mustBreak(const LineState &State) {
372 const FormatToken &Current = *State.NextToken;
373 const FormatToken &Previous = *Current.Previous;
374 const auto &CurrentState = State.Stack.back();
375 if (Style.BraceWrapping.BeforeLambdaBody && Current.CanBreakBefore &&
376 Current.is(TT_LambdaLBrace) && Previous.isNot(TT_LineComment)) {
377 auto LambdaBodyLength = getLengthToMatchingParen(Current, State.Stack);
378 return LambdaBodyLength > getColumnLimit(State);
379 }
380 if (Current.MustBreakBefore ||
381 (Current.is(TT_InlineASMColon) &&
382 (Style.BreakBeforeInlineASMColon == FormatStyle::BBIAS_Always ||
383 (Style.BreakBeforeInlineASMColon == FormatStyle::BBIAS_OnlyMultiline &&
384 Style.ColumnLimit > 0)))) {
385 return true;
386 }
387 if (CurrentState.BreakBeforeClosingBrace &&
388 (Current.closesBlockOrBlockTypeList(Style) ||
389 (Current.is(tok::r_brace) &&
390 Current.isBlockIndentedInitRBrace(Style)))) {
391 return true;
392 }
393 if (CurrentState.BreakBeforeClosingParen && Current.is(tok::r_paren))
394 return true;
395 if (Style.Language == FormatStyle::LK_ObjC &&
396 Style.ObjCBreakBeforeNestedBlockParam &&
397 Current.ObjCSelectorNameParts > 1 &&
398 Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) {
399 return true;
400 }
401 // Avoid producing inconsistent states by requiring breaks where they are not
402 // permitted for C# generic type constraints.
403 if (CurrentState.IsCSharpGenericTypeConstraint &&
404 Previous.isNot(TT_CSharpGenericTypeConstraintComma)) {
405 return false;
406 }
407 if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
408 (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
409 State.Line->First->isNot(TT_AttributeSquare) && Style.isCpp() &&
410 // FIXME: This is a temporary workaround for the case where clang-format
411 // sets BreakBeforeParameter to avoid bin packing and this creates a
412 // completely unnecessary line break after a template type that isn't
413 // line-wrapped.
414 (Previous.NestingLevel == 1 || Style.BinPackParameters)) ||
415 (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
416 Previous.isNot(tok::question)) ||
417 (!Style.BreakBeforeTernaryOperators &&
418 Previous.is(TT_ConditionalExpr))) &&
419 CurrentState.BreakBeforeParameter && !Current.isTrailingComment() &&
420 !Current.isOneOf(tok::r_paren, tok::r_brace)) {
421 return true;
422 }
423 if (CurrentState.IsChainedConditional &&
424 ((Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) &&
425 Current.is(tok::colon)) ||
426 (!Style.BreakBeforeTernaryOperators && Previous.is(TT_ConditionalExpr) &&
427 Previous.is(tok::colon)))) {
428 return true;
429 }
430 if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) ||
431 (Previous.is(TT_ArrayInitializerLSquare) &&
432 Previous.ParameterCount > 1) ||
433 opensProtoMessageField(Previous, Style)) &&
434 Style.ColumnLimit > 0 &&
435 getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 >
436 getColumnLimit(State)) {
437 return true;
438 }
439
440 const FormatToken &BreakConstructorInitializersToken =
441 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon
442 ? Previous
443 : Current;
444 if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) &&
445 (State.Column + State.Line->Last->TotalLength - Previous.TotalLength >
446 getColumnLimit(State) ||
447 CurrentState.BreakBeforeParameter) &&
448 (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
449 (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All ||
450 Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon ||
451 Style.ColumnLimit != 0)) {
452 return true;
453 }
454
455 if (Current.is(TT_ObjCMethodExpr) && Previous.isNot(TT_SelectorName) &&
456 State.Line->startsWith(TT_ObjCMethodSpecifier)) {
457 return true;
458 }
459 if (Current.is(TT_SelectorName) && Previous.isNot(tok::at) &&
460 CurrentState.ObjCSelectorNameFound && CurrentState.BreakBeforeParameter &&
461 (Style.ObjCBreakBeforeNestedBlockParam ||
462 !Current.startsSequence(TT_SelectorName, tok::colon, tok::caret))) {
463 return true;
464 }
465
466 unsigned NewLineColumn = getNewLineColumn(State);
467 if (Current.isMemberAccess() && Style.ColumnLimit != 0 &&
468 State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit &&
469 (State.Column > NewLineColumn ||
470 Current.NestingLevel < State.StartOfLineLevel)) {
471 return true;
472 }
473
474 if (startsSegmentOfBuilderTypeCall(Current) &&
475 (CurrentState.CallContinuation != 0 ||
476 CurrentState.BreakBeforeParameter) &&
477 // JavaScript is treated different here as there is a frequent pattern:
478 // SomeFunction(function() {
479 // ...
480 // }.bind(...));
481 // FIXME: We should find a more generic solution to this problem.
482 !(State.Column <= NewLineColumn && Style.isJavaScript()) &&
483 !(Previous.closesScopeAfterBlock() && State.Column <= NewLineColumn)) {
484 return true;
485 }
486
487 // If the template declaration spans multiple lines, force wrap before the
488 // function/class declaration.
489 if (Previous.ClosesTemplateDeclaration && CurrentState.BreakBeforeParameter &&
490 Current.CanBreakBefore) {
491 return true;
492 }
493
494 if (State.Line->First->isNot(tok::kw_enum) && State.Column <= NewLineColumn)
495 return false;
496
497 if (Style.AlwaysBreakBeforeMultilineStrings &&
498 (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth ||
499 Previous.is(tok::comma) || Current.NestingLevel < 2) &&
500 !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at,
501 Keywords.kw_dollar) &&
502 !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) &&
503 nextIsMultilineString(State)) {
504 return true;
505 }
506
507 // Using CanBreakBefore here and below takes care of the decision whether the
508 // current style uses wrapping before or after operators for the given
509 // operator.
510 if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) {
511 const auto PreviousPrecedence = Previous.getPrecedence();
512 if (PreviousPrecedence != prec::Assignment &&
513 CurrentState.BreakBeforeParameter && !Current.isTrailingComment()) {
514 const bool LHSIsBinaryExpr =
515 Previous.Previous && Previous.Previous->EndsBinaryExpression;
516 if (LHSIsBinaryExpr)
517 return true;
518 // If we need to break somewhere inside the LHS of a binary expression, we
519 // should also break after the operator. Otherwise, the formatting would
520 // hide the operator precedence, e.g. in:
521 // if (aaaaaaaaaaaaaa ==
522 // bbbbbbbbbbbbbb && c) {..
523 // For comparisons, we only apply this rule, if the LHS is a binary
524 // expression itself as otherwise, the line breaks seem superfluous.
525 // We need special cases for ">>" which we have split into two ">" while
526 // lexing in order to make template parsing easier.
527 const bool IsComparison =
528 (PreviousPrecedence == prec::Relational ||
529 PreviousPrecedence == prec::Equality ||
530 PreviousPrecedence == prec::Spaceship) &&
531 Previous.Previous &&
532 Previous.Previous->isNot(TT_BinaryOperator); // For >>.
533 if (!IsComparison)
534 return true;
535 }
536 } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore &&
537 CurrentState.BreakBeforeParameter) {
538 return true;
539 }
540
541 // Same as above, but for the first "<<" operator.
542 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) &&
543 CurrentState.BreakBeforeParameter && CurrentState.FirstLessLess == 0) {
544 return true;
545 }
546
547 if (Current.NestingLevel == 0 && !Current.isTrailingComment()) {
548 // Always break after "template <...>"(*) and leading annotations. This is
549 // only for cases where the entire line does not fit on a single line as a
550 // different LineFormatter would be used otherwise.
551 // *: Except when another option interferes with that, like concepts.
552 if (Previous.ClosesTemplateDeclaration) {
553 if (Current.is(tok::kw_concept)) {
554 switch (Style.BreakBeforeConceptDeclarations) {
555 case FormatStyle::BBCDS_Allowed:
556 break;
557 case FormatStyle::BBCDS_Always:
558 return true;
559 case FormatStyle::BBCDS_Never:
560 return false;
561 }
562 }
563 if (Current.is(TT_RequiresClause)) {
564 switch (Style.RequiresClausePosition) {
565 case FormatStyle::RCPS_SingleLine:
566 case FormatStyle::RCPS_WithPreceding:
567 return false;
568 default:
569 return true;
570 }
571 }
572 return Style.BreakTemplateDeclarations != FormatStyle::BTDS_No &&
573 (Style.BreakTemplateDeclarations != FormatStyle::BTDS_Leave ||
574 Current.NewlinesBefore > 0);
575 }
576 if (Previous.is(TT_FunctionAnnotationRParen) &&
577 State.Line->Type != LT_PreprocessorDirective) {
578 return true;
579 }
580 if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) &&
581 Current.isNot(TT_LeadingJavaAnnotation)) {
582 return true;
583 }
584 }
585
586 if (Style.isJavaScript() && Previous.is(tok::r_paren) &&
587 Previous.is(TT_JavaAnnotation)) {
588 // Break after the closing parenthesis of TypeScript decorators before
589 // functions, getters and setters.
590 static const llvm::StringSet<> BreakBeforeDecoratedTokens = {"get", "set",
591 "function"};
592 if (BreakBeforeDecoratedTokens.contains(Current.TokenText))
593 return true;
594 }
595
596 if (Current.is(TT_FunctionDeclarationName) &&
597 !State.Line->ReturnTypeWrapped &&
598 // Don't break before a C# function when no break after return type.
599 (!Style.isCSharp() ||
600 Style.BreakAfterReturnType > FormatStyle::RTBS_ExceptShortType) &&
601 // Don't always break between a JavaScript `function` and the function
602 // name.
603 !Style.isJavaScript() && Previous.isNot(tok::kw_template) &&
604 CurrentState.BreakBeforeParameter) {
605 return true;
606 }
607
608 // The following could be precomputed as they do not depend on the state.
609 // However, as they should take effect only if the UnwrappedLine does not fit
610 // into the ColumnLimit, they are checked here in the ContinuationIndenter.
611 if (Style.ColumnLimit != 0 && Previous.is(BK_Block) &&
612 Previous.is(tok::l_brace) &&
613 !Current.isOneOf(tok::r_brace, tok::comment)) {
614 return true;
615 }
616
617 if (Current.is(tok::lessless) &&
618 ((Previous.is(tok::identifier) && Previous.TokenText == "endl") ||
619 (Previous.Tok.isLiteral() && (Previous.TokenText.ends_with("\\n\"") ||
620 Previous.TokenText == "\'\\n\'")))) {
621 return true;
622 }
623
624 if (Previous.is(TT_BlockComment) && Previous.IsMultiline)
625 return true;
626
627 if (State.NoContinuation)
628 return true;
629
630 return false;
631 }
632
addTokenToState(LineState & State,bool Newline,bool DryRun,unsigned ExtraSpaces)633 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline,
634 bool DryRun,
635 unsigned ExtraSpaces) {
636 const FormatToken &Current = *State.NextToken;
637 assert(State.NextToken->Previous);
638 const FormatToken &Previous = *State.NextToken->Previous;
639
640 assert(!State.Stack.empty());
641 State.NoContinuation = false;
642
643 if (Current.is(TT_ImplicitStringLiteral) &&
644 (!Previous.Tok.getIdentifierInfo() ||
645 Previous.Tok.getIdentifierInfo()->getPPKeywordID() ==
646 tok::pp_not_keyword)) {
647 unsigned EndColumn =
648 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd());
649 if (Current.LastNewlineOffset != 0) {
650 // If there is a newline within this token, the final column will solely
651 // determined by the current end column.
652 State.Column = EndColumn;
653 } else {
654 unsigned StartColumn =
655 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin());
656 assert(EndColumn >= StartColumn);
657 State.Column += EndColumn - StartColumn;
658 }
659 moveStateToNextToken(State, DryRun, /*Newline=*/false);
660 return 0;
661 }
662
663 unsigned Penalty = 0;
664 if (Newline)
665 Penalty = addTokenOnNewLine(State, DryRun);
666 else
667 addTokenOnCurrentLine(State, DryRun, ExtraSpaces);
668
669 return moveStateToNextToken(State, DryRun, Newline) + Penalty;
670 }
671
addTokenOnCurrentLine(LineState & State,bool DryRun,unsigned ExtraSpaces)672 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
673 unsigned ExtraSpaces) {
674 FormatToken &Current = *State.NextToken;
675 assert(State.NextToken->Previous);
676 const FormatToken &Previous = *State.NextToken->Previous;
677 auto &CurrentState = State.Stack.back();
678
679 bool DisallowLineBreaksOnThisLine =
680 Style.LambdaBodyIndentation == FormatStyle::LBI_Signature &&
681 Style.isCpp() && [&Current] {
682 // Deal with lambda arguments in C++. The aim here is to ensure that we
683 // don't over-indent lambda function bodies when lambdas are passed as
684 // arguments to function calls. We do this by ensuring that either all
685 // arguments (including any lambdas) go on the same line as the function
686 // call, or we break before the first argument.
687 const auto *Prev = Current.Previous;
688 if (!Prev)
689 return false;
690 // For example, `/*Newline=*/false`.
691 if (Prev->is(TT_BlockComment) && Current.SpacesRequiredBefore == 0)
692 return false;
693 const auto *PrevNonComment = Current.getPreviousNonComment();
694 if (!PrevNonComment || PrevNonComment->isNot(tok::l_paren))
695 return false;
696 if (Current.isOneOf(tok::comment, tok::l_paren, TT_LambdaLSquare))
697 return false;
698 auto BlockParameterCount = PrevNonComment->BlockParameterCount;
699 if (BlockParameterCount == 0)
700 return false;
701
702 // Multiple lambdas in the same function call.
703 if (BlockParameterCount > 1)
704 return true;
705
706 // A lambda followed by another arg.
707 if (!PrevNonComment->Role)
708 return false;
709 auto Comma = PrevNonComment->Role->lastComma();
710 if (!Comma)
711 return false;
712 auto Next = Comma->getNextNonComment();
713 return Next &&
714 !Next->isOneOf(TT_LambdaLSquare, tok::l_brace, tok::caret);
715 }();
716
717 if (DisallowLineBreaksOnThisLine)
718 State.NoLineBreak = true;
719
720 if (Current.is(tok::equal) &&
721 (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) &&
722 CurrentState.VariablePos == 0 &&
723 (!Previous.Previous ||
724 Previous.Previous->isNot(TT_DesignatedInitializerPeriod))) {
725 CurrentState.VariablePos = State.Column;
726 // Move over * and & if they are bound to the variable name.
727 const FormatToken *Tok = &Previous;
728 while (Tok && CurrentState.VariablePos >= Tok->ColumnWidth) {
729 CurrentState.VariablePos -= Tok->ColumnWidth;
730 if (Tok->SpacesRequiredBefore != 0)
731 break;
732 Tok = Tok->Previous;
733 }
734 if (Previous.PartOfMultiVariableDeclStmt)
735 CurrentState.LastSpace = CurrentState.VariablePos;
736 }
737
738 unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces;
739
740 // Indent preprocessor directives after the hash if required.
741 int PPColumnCorrection = 0;
742 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash &&
743 Previous.is(tok::hash) && State.FirstIndent > 0 &&
744 &Previous == State.Line->First &&
745 (State.Line->Type == LT_PreprocessorDirective ||
746 State.Line->Type == LT_ImportStatement)) {
747 Spaces += State.FirstIndent;
748
749 // For preprocessor indent with tabs, State.Column will be 1 because of the
750 // hash. This causes second-level indents onward to have an extra space
751 // after the tabs. We avoid this misalignment by subtracting 1 from the
752 // column value passed to replaceWhitespace().
753 if (Style.UseTab != FormatStyle::UT_Never)
754 PPColumnCorrection = -1;
755 }
756
757 if (!DryRun) {
758 Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces,
759 State.Column + Spaces + PPColumnCorrection,
760 /*IsAligned=*/false, State.Line->InMacroBody);
761 }
762
763 // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance
764 // declaration unless there is multiple inheritance.
765 if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma &&
766 Current.is(TT_InheritanceColon)) {
767 CurrentState.NoLineBreak = true;
768 }
769 if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon &&
770 Previous.is(TT_InheritanceColon)) {
771 CurrentState.NoLineBreak = true;
772 }
773
774 if (Current.is(TT_SelectorName) && !CurrentState.ObjCSelectorNameFound) {
775 unsigned MinIndent = std::max(
776 State.FirstIndent + Style.ContinuationIndentWidth, CurrentState.Indent);
777 unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth;
778 if (Current.LongestObjCSelectorName == 0)
779 CurrentState.AlignColons = false;
780 else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos)
781 CurrentState.ColonPos = MinIndent + Current.LongestObjCSelectorName;
782 else
783 CurrentState.ColonPos = FirstColonPos;
784 }
785
786 // In "AlwaysBreak" or "BlockIndent" mode, enforce wrapping directly after the
787 // parenthesis by disallowing any further line breaks if there is no line
788 // break after the opening parenthesis. Don't break if it doesn't conserve
789 // columns.
790 auto IsOpeningBracket = [&](const FormatToken &Tok) {
791 auto IsStartOfBracedList = [&]() {
792 return Tok.is(tok::l_brace) && Tok.isNot(BK_Block) &&
793 Style.Cpp11BracedListStyle;
794 };
795 if (!Tok.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) &&
796 !IsStartOfBracedList()) {
797 return false;
798 }
799 if (!Tok.Previous)
800 return true;
801 if (Tok.Previous->isIf())
802 return Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak;
803 return !Tok.Previous->isOneOf(TT_CastRParen, tok::kw_for, tok::kw_while,
804 tok::kw_switch);
805 };
806 if ((Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak ||
807 Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent) &&
808 IsOpeningBracket(Previous) && State.Column > getNewLineColumn(State) &&
809 // Don't do this for simple (no expressions) one-argument function calls
810 // as that feels like needlessly wasting whitespace, e.g.:
811 //
812 // caaaaaaaaaaaall(
813 // caaaaaaaaaaaall(
814 // caaaaaaaaaaaall(
815 // caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa))));
816 Current.FakeLParens.size() > 0 &&
817 Current.FakeLParens.back() > prec::Unknown) {
818 CurrentState.NoLineBreak = true;
819 }
820 if (Previous.is(TT_TemplateString) && Previous.opensScope())
821 CurrentState.NoLineBreak = true;
822
823 // Align following lines within parentheses / brackets if configured.
824 // Note: This doesn't apply to macro expansion lines, which are MACRO( , , )
825 // with args as children of the '(' and ',' tokens. It does not make sense to
826 // align the commas with the opening paren.
827 if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign &&
828 !CurrentState.IsCSharpGenericTypeConstraint && Previous.opensScope() &&
829 Previous.isNot(TT_ObjCMethodExpr) && Previous.isNot(TT_RequiresClause) &&
830 Previous.isNot(TT_TableGenDAGArgOpener) &&
831 Previous.isNot(TT_TableGenDAGArgOpenerToBreak) &&
832 !(Current.MacroParent && Previous.MacroParent) &&
833 (Current.isNot(TT_LineComment) ||
834 Previous.isOneOf(BK_BracedInit, TT_VerilogMultiLineListLParen))) {
835 CurrentState.Indent = State.Column + Spaces;
836 CurrentState.IsAligned = true;
837 }
838 if (CurrentState.AvoidBinPacking && startsNextParameter(Current, Style))
839 CurrentState.NoLineBreak = true;
840 if (startsSegmentOfBuilderTypeCall(Current) &&
841 State.Column > getNewLineColumn(State)) {
842 CurrentState.ContainsUnwrappedBuilder = true;
843 }
844
845 if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java)
846 CurrentState.NoLineBreak = true;
847 if (Current.isMemberAccess() && Previous.is(tok::r_paren) &&
848 (Previous.MatchingParen &&
849 (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10))) {
850 // If there is a function call with long parameters, break before trailing
851 // calls. This prevents things like:
852 // EXPECT_CALL(SomeLongParameter).Times(
853 // 2);
854 // We don't want to do this for short parameters as they can just be
855 // indexes.
856 CurrentState.NoLineBreak = true;
857 }
858
859 // Don't allow the RHS of an operator to be split over multiple lines unless
860 // there is a line-break right after the operator.
861 // Exclude relational operators, as there, it is always more desirable to
862 // have the LHS 'left' of the RHS.
863 const FormatToken *P = Current.getPreviousNonComment();
864 if (Current.isNot(tok::comment) && P &&
865 (P->isOneOf(TT_BinaryOperator, tok::comma) ||
866 (P->is(TT_ConditionalExpr) && P->is(tok::colon))) &&
867 !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) &&
868 P->getPrecedence() != prec::Assignment &&
869 P->getPrecedence() != prec::Relational &&
870 P->getPrecedence() != prec::Spaceship) {
871 bool BreakBeforeOperator =
872 P->MustBreakBefore || P->is(tok::lessless) ||
873 (P->is(TT_BinaryOperator) &&
874 Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) ||
875 (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators);
876 // Don't do this if there are only two operands. In these cases, there is
877 // always a nice vertical separation between them and the extra line break
878 // does not help.
879 bool HasTwoOperands = P->OperatorIndex == 0 && !P->NextOperator &&
880 P->isNot(TT_ConditionalExpr);
881 if ((!BreakBeforeOperator &&
882 !(HasTwoOperands &&
883 Style.AlignOperands != FormatStyle::OAS_DontAlign)) ||
884 (!CurrentState.LastOperatorWrapped && BreakBeforeOperator)) {
885 CurrentState.NoLineBreakInOperand = true;
886 }
887 }
888
889 State.Column += Spaces;
890 if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) &&
891 Previous.Previous &&
892 (Previous.Previous->is(tok::kw_for) || Previous.Previous->isIf())) {
893 // Treat the condition inside an if as if it was a second function
894 // parameter, i.e. let nested calls have a continuation indent.
895 CurrentState.LastSpace = State.Column;
896 CurrentState.NestedBlockIndent = State.Column;
897 } else if (!Current.isOneOf(tok::comment, tok::caret) &&
898 ((Previous.is(tok::comma) &&
899 Previous.isNot(TT_OverloadedOperator)) ||
900 (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) {
901 CurrentState.LastSpace = State.Column;
902 } else if (Previous.is(TT_CtorInitializerColon) &&
903 (!Current.isTrailingComment() || Current.NewlinesBefore > 0) &&
904 Style.BreakConstructorInitializers ==
905 FormatStyle::BCIS_AfterColon) {
906 CurrentState.Indent = State.Column;
907 CurrentState.LastSpace = State.Column;
908 } else if (Previous.isOneOf(TT_ConditionalExpr, TT_CtorInitializerColon)) {
909 CurrentState.LastSpace = State.Column;
910 } else if (Previous.is(TT_BinaryOperator) &&
911 ((Previous.getPrecedence() != prec::Assignment &&
912 (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 ||
913 Previous.NextOperator)) ||
914 Current.StartsBinaryExpression)) {
915 // Indent relative to the RHS of the expression unless this is a simple
916 // assignment without binary expression on the RHS.
917 if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None)
918 CurrentState.LastSpace = State.Column;
919 } else if (Previous.is(TT_InheritanceColon)) {
920 CurrentState.Indent = State.Column;
921 CurrentState.LastSpace = State.Column;
922 } else if (Current.is(TT_CSharpGenericTypeConstraintColon)) {
923 CurrentState.ColonPos = State.Column;
924 } else if (Previous.opensScope()) {
925 // If a function has a trailing call, indent all parameters from the
926 // opening parenthesis. This avoids confusing indents like:
927 // OuterFunction(InnerFunctionCall( // break
928 // ParameterToInnerFunction)) // break
929 // .SecondInnerFunctionCall();
930 if (Previous.MatchingParen) {
931 const FormatToken *Next = Previous.MatchingParen->getNextNonComment();
932 if (Next && Next->isMemberAccess() && State.Stack.size() > 1 &&
933 State.Stack[State.Stack.size() - 2].CallContinuation == 0) {
934 CurrentState.LastSpace = State.Column;
935 }
936 }
937 }
938 }
939
addTokenOnNewLine(LineState & State,bool DryRun)940 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
941 bool DryRun) {
942 FormatToken &Current = *State.NextToken;
943 assert(State.NextToken->Previous);
944 const FormatToken &Previous = *State.NextToken->Previous;
945 auto &CurrentState = State.Stack.back();
946
947 // Extra penalty that needs to be added because of the way certain line
948 // breaks are chosen.
949 unsigned Penalty = 0;
950
951 const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
952 const FormatToken *NextNonComment = Previous.getNextNonComment();
953 if (!NextNonComment)
954 NextNonComment = &Current;
955 // The first line break on any NestingLevel causes an extra penalty in order
956 // prefer similar line breaks.
957 if (!CurrentState.ContainsLineBreak)
958 Penalty += 15;
959 CurrentState.ContainsLineBreak = true;
960
961 Penalty += State.NextToken->SplitPenalty;
962
963 // Breaking before the first "<<" is generally not desirable if the LHS is
964 // short. Also always add the penalty if the LHS is split over multiple lines
965 // to avoid unnecessary line breaks that just work around this penalty.
966 if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess == 0 &&
967 (State.Column <= Style.ColumnLimit / 3 ||
968 CurrentState.BreakBeforeParameter)) {
969 Penalty += Style.PenaltyBreakFirstLessLess;
970 }
971
972 State.Column = getNewLineColumn(State);
973
974 // Add Penalty proportional to amount of whitespace away from FirstColumn
975 // This tends to penalize several lines that are far-right indented,
976 // and prefers a line-break prior to such a block, e.g:
977 //
978 // Constructor() :
979 // member(value), looooooooooooooooong_member(
980 // looooooooooong_call(param_1, param_2, param_3))
981 // would then become
982 // Constructor() :
983 // member(value),
984 // looooooooooooooooong_member(
985 // looooooooooong_call(param_1, param_2, param_3))
986 if (State.Column > State.FirstIndent) {
987 Penalty +=
988 Style.PenaltyIndentedWhitespace * (State.Column - State.FirstIndent);
989 }
990
991 // Indent nested blocks relative to this column, unless in a very specific
992 // JavaScript special case where:
993 //
994 // var loooooong_name =
995 // function() {
996 // // code
997 // }
998 //
999 // is common and should be formatted like a free-standing function. The same
1000 // goes for wrapping before the lambda return type arrow.
1001 if (Current.isNot(TT_LambdaArrow) &&
1002 (!Style.isJavaScript() || Current.NestingLevel != 0 ||
1003 !PreviousNonComment || PreviousNonComment->isNot(tok::equal) ||
1004 !Current.isOneOf(Keywords.kw_async, Keywords.kw_function))) {
1005 CurrentState.NestedBlockIndent = State.Column;
1006 }
1007
1008 if (NextNonComment->isMemberAccess()) {
1009 if (CurrentState.CallContinuation == 0)
1010 CurrentState.CallContinuation = State.Column;
1011 } else if (NextNonComment->is(TT_SelectorName)) {
1012 if (!CurrentState.ObjCSelectorNameFound) {
1013 if (NextNonComment->LongestObjCSelectorName == 0) {
1014 CurrentState.AlignColons = false;
1015 } else {
1016 CurrentState.ColonPos =
1017 (shouldIndentWrappedSelectorName(Style, State.Line->Type)
1018 ? std::max(CurrentState.Indent,
1019 State.FirstIndent + Style.ContinuationIndentWidth)
1020 : CurrentState.Indent) +
1021 std::max(NextNonComment->LongestObjCSelectorName,
1022 NextNonComment->ColumnWidth);
1023 }
1024 } else if (CurrentState.AlignColons &&
1025 CurrentState.ColonPos <= NextNonComment->ColumnWidth) {
1026 CurrentState.ColonPos = State.Column + NextNonComment->ColumnWidth;
1027 }
1028 } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1029 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1030 // FIXME: This is hacky, find a better way. The problem is that in an ObjC
1031 // method expression, the block should be aligned to the line starting it,
1032 // e.g.:
1033 // [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason
1034 // ^(int *i) {
1035 // // ...
1036 // }];
1037 // Thus, we set LastSpace of the next higher NestingLevel, to which we move
1038 // when we consume all of the "}"'s FakeRParens at the "{".
1039 if (State.Stack.size() > 1) {
1040 State.Stack[State.Stack.size() - 2].LastSpace =
1041 std::max(CurrentState.LastSpace, CurrentState.Indent) +
1042 Style.ContinuationIndentWidth;
1043 }
1044 }
1045
1046 if ((PreviousNonComment &&
1047 PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
1048 !CurrentState.AvoidBinPacking) ||
1049 Previous.is(TT_BinaryOperator)) {
1050 CurrentState.BreakBeforeParameter = false;
1051 }
1052 if (PreviousNonComment &&
1053 (PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) ||
1054 PreviousNonComment->ClosesRequiresClause) &&
1055 Current.NestingLevel == 0) {
1056 CurrentState.BreakBeforeParameter = false;
1057 }
1058 if (NextNonComment->is(tok::question) ||
1059 (PreviousNonComment && PreviousNonComment->is(tok::question))) {
1060 CurrentState.BreakBeforeParameter = true;
1061 }
1062 if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
1063 CurrentState.BreakBeforeParameter = false;
1064
1065 if (!DryRun) {
1066 unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
1067 if (Current.is(tok::r_brace) && Current.MatchingParen &&
1068 // Only strip trailing empty lines for l_braces that have children, i.e.
1069 // for function expressions (lambdas, arrows, etc).
1070 !Current.MatchingParen->Children.empty()) {
1071 // lambdas and arrow functions are expressions, thus their r_brace is not
1072 // on its own line, and thus not covered by UnwrappedLineFormatter's logic
1073 // about removing empty lines on closing blocks. Special case them here.
1074 MaxEmptyLinesToKeep = 1;
1075 }
1076 unsigned Newlines =
1077 std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep));
1078 bool ContinuePPDirective =
1079 State.Line->InPPDirective && State.Line->Type != LT_ImportStatement;
1080 Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column,
1081 CurrentState.IsAligned, ContinuePPDirective);
1082 }
1083
1084 if (!Current.isTrailingComment())
1085 CurrentState.LastSpace = State.Column;
1086 if (Current.is(tok::lessless)) {
1087 // If we are breaking before a "<<", we always want to indent relative to
1088 // RHS. This is necessary only for "<<", as we special-case it and don't
1089 // always indent relative to the RHS.
1090 CurrentState.LastSpace += 3; // 3 -> width of "<< ".
1091 }
1092
1093 State.StartOfLineLevel = Current.NestingLevel;
1094 State.LowestLevelOnLine = Current.NestingLevel;
1095
1096 // Any break on this level means that the parent level has been broken
1097 // and we need to avoid bin packing there.
1098 bool NestedBlockSpecialCase =
1099 (!Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
1100 State.Stack[State.Stack.size() - 2].NestedBlockInlined) ||
1101 (Style.Language == FormatStyle::LK_ObjC && Current.is(tok::r_brace) &&
1102 State.Stack.size() > 1 && !Style.ObjCBreakBeforeNestedBlockParam);
1103 // Do not force parameter break for statements with requires expressions.
1104 NestedBlockSpecialCase =
1105 NestedBlockSpecialCase ||
1106 (Current.MatchingParen &&
1107 Current.MatchingParen->is(TT_RequiresExpressionLBrace));
1108 if (!NestedBlockSpecialCase) {
1109 auto ParentLevelIt = std::next(State.Stack.rbegin());
1110 if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1111 Current.MatchingParen && Current.MatchingParen->is(TT_LambdaLBrace)) {
1112 // If the first character on the new line is a lambda's closing brace, the
1113 // stack still contains that lambda's parenthesis. As such, we need to
1114 // recurse further down the stack than usual to find the parenthesis level
1115 // containing the lambda, which is where we want to set
1116 // BreakBeforeParameter.
1117 //
1118 // We specifically special case "OuterScope"-formatted lambdas here
1119 // because, when using that setting, breaking before the parameter
1120 // directly following the lambda is particularly unsightly. However, when
1121 // "OuterScope" is not set, the logic to find the parent parenthesis level
1122 // still appears to be sometimes incorrect. It has not been fixed yet
1123 // because it would lead to significant changes in existing behaviour.
1124 //
1125 // TODO: fix the non-"OuterScope" case too.
1126 auto FindCurrentLevel = [&](const auto &It) {
1127 return std::find_if(It, State.Stack.rend(), [](const auto &PState) {
1128 return PState.Tok != nullptr; // Ignore fake parens.
1129 });
1130 };
1131 auto MaybeIncrement = [&](const auto &It) {
1132 return It != State.Stack.rend() ? std::next(It) : It;
1133 };
1134 auto LambdaLevelIt = FindCurrentLevel(State.Stack.rbegin());
1135 auto LevelContainingLambdaIt =
1136 FindCurrentLevel(MaybeIncrement(LambdaLevelIt));
1137 ParentLevelIt = MaybeIncrement(LevelContainingLambdaIt);
1138 }
1139 for (auto I = ParentLevelIt, E = State.Stack.rend(); I != E; ++I)
1140 I->BreakBeforeParameter = true;
1141 }
1142
1143 if (PreviousNonComment &&
1144 !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) &&
1145 ((PreviousNonComment->isNot(TT_TemplateCloser) &&
1146 !PreviousNonComment->ClosesRequiresClause) ||
1147 Current.NestingLevel != 0) &&
1148 !PreviousNonComment->isOneOf(
1149 TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation,
1150 TT_LeadingJavaAnnotation) &&
1151 Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope() &&
1152 // We don't want to enforce line breaks for subsequent arguments just
1153 // because we have been forced to break before a lambda body.
1154 (!Style.BraceWrapping.BeforeLambdaBody ||
1155 Current.isNot(TT_LambdaLBrace))) {
1156 CurrentState.BreakBeforeParameter = true;
1157 }
1158
1159 // If we break after { or the [ of an array initializer, we should also break
1160 // before the corresponding } or ].
1161 if (PreviousNonComment &&
1162 (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1163 opensProtoMessageField(*PreviousNonComment, Style))) {
1164 CurrentState.BreakBeforeClosingBrace = true;
1165 }
1166
1167 if (PreviousNonComment && PreviousNonComment->is(tok::l_paren)) {
1168 CurrentState.BreakBeforeClosingParen =
1169 Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent;
1170 }
1171
1172 if (CurrentState.AvoidBinPacking) {
1173 // If we are breaking after '(', '{', '<', or this is the break after a ':'
1174 // to start a member initializer list in a constructor, this should not
1175 // be considered bin packing unless the relevant AllowAll option is false or
1176 // this is a dict/object literal.
1177 bool PreviousIsBreakingCtorInitializerColon =
1178 PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1179 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon;
1180 bool AllowAllConstructorInitializersOnNextLine =
1181 Style.PackConstructorInitializers == FormatStyle::PCIS_NextLine ||
1182 Style.PackConstructorInitializers == FormatStyle::PCIS_NextLineOnly;
1183 if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) ||
1184 PreviousIsBreakingCtorInitializerColon) ||
1185 (!Style.AllowAllParametersOfDeclarationOnNextLine &&
1186 State.Line->MustBeDeclaration) ||
1187 (!Style.AllowAllArgumentsOnNextLine &&
1188 !State.Line->MustBeDeclaration) ||
1189 (!AllowAllConstructorInitializersOnNextLine &&
1190 PreviousIsBreakingCtorInitializerColon) ||
1191 Previous.is(TT_DictLiteral)) {
1192 CurrentState.BreakBeforeParameter = true;
1193 }
1194
1195 // If we are breaking after a ':' to start a member initializer list,
1196 // and we allow all arguments on the next line, we should not break
1197 // before the next parameter.
1198 if (PreviousIsBreakingCtorInitializerColon &&
1199 AllowAllConstructorInitializersOnNextLine) {
1200 CurrentState.BreakBeforeParameter = false;
1201 }
1202 }
1203
1204 return Penalty;
1205 }
1206
getNewLineColumn(const LineState & State)1207 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) {
1208 if (!State.NextToken || !State.NextToken->Previous)
1209 return 0;
1210
1211 FormatToken &Current = *State.NextToken;
1212 const auto &CurrentState = State.Stack.back();
1213
1214 if (CurrentState.IsCSharpGenericTypeConstraint &&
1215 Current.isNot(TT_CSharpGenericTypeConstraint)) {
1216 return CurrentState.ColonPos + 2;
1217 }
1218
1219 const FormatToken &Previous = *Current.Previous;
1220 // If we are continuing an expression, we want to use the continuation indent.
1221 unsigned ContinuationIndent =
1222 std::max(CurrentState.LastSpace, CurrentState.Indent) +
1223 Style.ContinuationIndentWidth;
1224 const FormatToken *PreviousNonComment = Current.getPreviousNonComment();
1225 const FormatToken *NextNonComment = Previous.getNextNonComment();
1226 if (!NextNonComment)
1227 NextNonComment = &Current;
1228
1229 // Java specific bits.
1230 if (Style.Language == FormatStyle::LK_Java &&
1231 Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends)) {
1232 return std::max(CurrentState.LastSpace,
1233 CurrentState.Indent + Style.ContinuationIndentWidth);
1234 }
1235
1236 // Indentation of the statement following a Verilog case label is taken care
1237 // of in moveStateToNextToken.
1238 if (Style.isVerilog() && PreviousNonComment &&
1239 Keywords.isVerilogEndOfLabel(*PreviousNonComment)) {
1240 return State.FirstIndent;
1241 }
1242
1243 if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths &&
1244 State.Line->First->is(tok::kw_enum)) {
1245 return (Style.IndentWidth * State.Line->First->IndentLevel) +
1246 Style.IndentWidth;
1247 }
1248
1249 if ((NextNonComment->is(tok::l_brace) && NextNonComment->is(BK_Block)) ||
1250 (Style.isVerilog() && Keywords.isVerilogBegin(*NextNonComment))) {
1251 if (Current.NestingLevel == 0 ||
1252 (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
1253 State.NextToken->is(TT_LambdaLBrace))) {
1254 return State.FirstIndent;
1255 }
1256 return CurrentState.Indent;
1257 }
1258 if (Current.is(TT_LambdaArrow) &&
1259 Previous.isOneOf(tok::kw_noexcept, tok::kw_mutable, tok::kw_constexpr,
1260 tok::kw_consteval, tok::kw_static, TT_AttributeSquare)) {
1261 return ContinuationIndent;
1262 }
1263 if ((Current.isOneOf(tok::r_brace, tok::r_square) ||
1264 (Current.is(tok::greater) && (Style.isProto() || Style.isTableGen()))) &&
1265 State.Stack.size() > 1) {
1266 if (Current.closesBlockOrBlockTypeList(Style))
1267 return State.Stack[State.Stack.size() - 2].NestedBlockIndent;
1268 if (Current.MatchingParen && Current.MatchingParen->is(BK_BracedInit))
1269 return State.Stack[State.Stack.size() - 2].LastSpace;
1270 return State.FirstIndent;
1271 }
1272 // Indent a closing parenthesis at the previous level if followed by a semi,
1273 // const, or opening brace. This allows indentations such as:
1274 // foo(
1275 // a,
1276 // );
1277 // int Foo::getter(
1278 // //
1279 // ) const {
1280 // return foo;
1281 // }
1282 // function foo(
1283 // a,
1284 // ) {
1285 // code(); //
1286 // }
1287 if (Current.is(tok::r_paren) && State.Stack.size() > 1 &&
1288 (!Current.Next ||
1289 Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace))) {
1290 return State.Stack[State.Stack.size() - 2].LastSpace;
1291 }
1292 // When DAGArg closer exists top of line, it should be aligned in the similar
1293 // way as function call above.
1294 if (Style.isTableGen() && Current.is(TT_TableGenDAGArgCloser) &&
1295 State.Stack.size() > 1) {
1296 return State.Stack[State.Stack.size() - 2].LastSpace;
1297 }
1298 if (Style.AlignAfterOpenBracket == FormatStyle::BAS_BlockIndent &&
1299 (Current.is(tok::r_paren) ||
1300 (Current.is(tok::r_brace) && Current.MatchingParen &&
1301 Current.MatchingParen->is(BK_BracedInit))) &&
1302 State.Stack.size() > 1) {
1303 return State.Stack[State.Stack.size() - 2].LastSpace;
1304 }
1305 if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope())
1306 return State.Stack[State.Stack.size() - 2].LastSpace;
1307 // Field labels in a nested type should be aligned to the brace. For example
1308 // in ProtoBuf:
1309 // optional int32 b = 2 [(foo_options) = {aaaaaaaaaaaaaaaaaaa: 123,
1310 // bbbbbbbbbbbbbbbbbbbbbbbb:"baz"}];
1311 // For Verilog, a quote following a brace is treated as an identifier. And
1312 // Both braces and colons get annotated as TT_DictLiteral. So we have to
1313 // check.
1314 if (Current.is(tok::identifier) && Current.Next &&
1315 (!Style.isVerilog() || Current.Next->is(tok::colon)) &&
1316 (Current.Next->is(TT_DictLiteral) ||
1317 (Style.isProto() && Current.Next->isOneOf(tok::less, tok::l_brace)))) {
1318 return CurrentState.Indent;
1319 }
1320 if (NextNonComment->is(TT_ObjCStringLiteral) &&
1321 State.StartOfStringLiteral != 0) {
1322 return State.StartOfStringLiteral - 1;
1323 }
1324 if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0)
1325 return State.StartOfStringLiteral;
1326 if (NextNonComment->is(tok::lessless) && CurrentState.FirstLessLess != 0)
1327 return CurrentState.FirstLessLess;
1328 if (NextNonComment->isMemberAccess()) {
1329 if (CurrentState.CallContinuation == 0)
1330 return ContinuationIndent;
1331 return CurrentState.CallContinuation;
1332 }
1333 if (CurrentState.QuestionColumn != 0 &&
1334 ((NextNonComment->is(tok::colon) &&
1335 NextNonComment->is(TT_ConditionalExpr)) ||
1336 Previous.is(TT_ConditionalExpr))) {
1337 if (((NextNonComment->is(tok::colon) && NextNonComment->Next &&
1338 !NextNonComment->Next->FakeLParens.empty() &&
1339 NextNonComment->Next->FakeLParens.back() == prec::Conditional) ||
1340 (Previous.is(tok::colon) && !Current.FakeLParens.empty() &&
1341 Current.FakeLParens.back() == prec::Conditional)) &&
1342 !CurrentState.IsWrappedConditional) {
1343 // NOTE: we may tweak this slightly:
1344 // * not remove the 'lead' ContinuationIndentWidth
1345 // * always un-indent by the operator when
1346 // BreakBeforeTernaryOperators=true
1347 unsigned Indent = CurrentState.Indent;
1348 if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1349 Indent -= Style.ContinuationIndentWidth;
1350 if (Style.BreakBeforeTernaryOperators && CurrentState.UnindentOperator)
1351 Indent -= 2;
1352 return Indent;
1353 }
1354 return CurrentState.QuestionColumn;
1355 }
1356 if (Previous.is(tok::comma) && CurrentState.VariablePos != 0)
1357 return CurrentState.VariablePos;
1358 if (Current.is(TT_RequiresClause)) {
1359 if (Style.IndentRequiresClause)
1360 return CurrentState.Indent + Style.IndentWidth;
1361 switch (Style.RequiresClausePosition) {
1362 case FormatStyle::RCPS_OwnLine:
1363 case FormatStyle::RCPS_WithFollowing:
1364 return CurrentState.Indent;
1365 default:
1366 break;
1367 }
1368 }
1369 if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon,
1370 TT_InheritanceComma)) {
1371 return State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1372 }
1373 if ((PreviousNonComment &&
1374 (PreviousNonComment->ClosesTemplateDeclaration ||
1375 PreviousNonComment->ClosesRequiresClause ||
1376 (PreviousNonComment->is(TT_AttributeMacro) &&
1377 Current.isNot(tok::l_paren)) ||
1378 PreviousNonComment->isOneOf(
1379 TT_AttributeRParen, TT_AttributeSquare, TT_FunctionAnnotationRParen,
1380 TT_JavaAnnotation, TT_LeadingJavaAnnotation))) ||
1381 (!Style.IndentWrappedFunctionNames &&
1382 NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName))) {
1383 return std::max(CurrentState.LastSpace, CurrentState.Indent);
1384 }
1385 if (NextNonComment->is(TT_SelectorName)) {
1386 if (!CurrentState.ObjCSelectorNameFound) {
1387 unsigned MinIndent = CurrentState.Indent;
1388 if (shouldIndentWrappedSelectorName(Style, State.Line->Type)) {
1389 MinIndent = std::max(MinIndent,
1390 State.FirstIndent + Style.ContinuationIndentWidth);
1391 }
1392 // If LongestObjCSelectorName is 0, we are indenting the first
1393 // part of an ObjC selector (or a selector component which is
1394 // not colon-aligned due to block formatting).
1395 //
1396 // Otherwise, we are indenting a subsequent part of an ObjC
1397 // selector which should be colon-aligned to the longest
1398 // component of the ObjC selector.
1399 //
1400 // In either case, we want to respect Style.IndentWrappedFunctionNames.
1401 return MinIndent +
1402 std::max(NextNonComment->LongestObjCSelectorName,
1403 NextNonComment->ColumnWidth) -
1404 NextNonComment->ColumnWidth;
1405 }
1406 if (!CurrentState.AlignColons)
1407 return CurrentState.Indent;
1408 if (CurrentState.ColonPos > NextNonComment->ColumnWidth)
1409 return CurrentState.ColonPos - NextNonComment->ColumnWidth;
1410 return CurrentState.Indent;
1411 }
1412 if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr))
1413 return CurrentState.ColonPos;
1414 if (NextNonComment->is(TT_ArraySubscriptLSquare)) {
1415 if (CurrentState.StartOfArraySubscripts != 0) {
1416 return CurrentState.StartOfArraySubscripts;
1417 } else if (Style.isCSharp()) { // C# allows `["key"] = value` inside object
1418 // initializers.
1419 return CurrentState.Indent;
1420 }
1421 return ContinuationIndent;
1422 }
1423
1424 // OpenMP clauses want to get additional indentation when they are pushed onto
1425 // the next line.
1426 if (State.Line->InPragmaDirective) {
1427 FormatToken *PragmaType = State.Line->First->Next->Next;
1428 if (PragmaType && PragmaType->TokenText == "omp")
1429 return CurrentState.Indent + Style.ContinuationIndentWidth;
1430 }
1431
1432 // This ensure that we correctly format ObjC methods calls without inputs,
1433 // i.e. where the last element isn't selector like: [callee method];
1434 if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 &&
1435 NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr)) {
1436 return CurrentState.Indent;
1437 }
1438
1439 if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) ||
1440 Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon)) {
1441 return ContinuationIndent;
1442 }
1443 if (PreviousNonComment && PreviousNonComment->is(tok::colon) &&
1444 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) {
1445 return ContinuationIndent;
1446 }
1447 if (NextNonComment->is(TT_CtorInitializerComma))
1448 return CurrentState.Indent;
1449 if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) &&
1450 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1451 return CurrentState.Indent;
1452 }
1453 if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) &&
1454 Style.BreakInheritanceList == FormatStyle::BILS_AfterColon) {
1455 return CurrentState.Indent;
1456 }
1457 if (Previous.is(tok::r_paren) &&
1458 Previous.isNot(TT_TableGenDAGArgOperatorToBreak) &&
1459 !Current.isBinaryOperator() &&
1460 !Current.isOneOf(tok::colon, tok::comment)) {
1461 return ContinuationIndent;
1462 }
1463 if (Current.is(TT_ProtoExtensionLSquare))
1464 return CurrentState.Indent;
1465 if (Current.isBinaryOperator() && CurrentState.UnindentOperator) {
1466 return CurrentState.Indent - Current.Tok.getLength() -
1467 Current.SpacesRequiredBefore;
1468 }
1469 if (Current.is(tok::comment) && NextNonComment->isBinaryOperator() &&
1470 CurrentState.UnindentOperator) {
1471 return CurrentState.Indent - NextNonComment->Tok.getLength() -
1472 NextNonComment->SpacesRequiredBefore;
1473 }
1474 if (CurrentState.Indent == State.FirstIndent && PreviousNonComment &&
1475 !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma)) {
1476 // Ensure that we fall back to the continuation indent width instead of
1477 // just flushing continuations left.
1478 return CurrentState.Indent + Style.ContinuationIndentWidth;
1479 }
1480 return CurrentState.Indent;
1481 }
1482
hasNestedBlockInlined(const FormatToken * Previous,const FormatToken & Current,const FormatStyle & Style)1483 static bool hasNestedBlockInlined(const FormatToken *Previous,
1484 const FormatToken &Current,
1485 const FormatStyle &Style) {
1486 if (Previous->isNot(tok::l_paren))
1487 return true;
1488 if (Previous->ParameterCount > 1)
1489 return true;
1490
1491 // Also a nested block if contains a lambda inside function with 1 parameter.
1492 return Style.BraceWrapping.BeforeLambdaBody && Current.is(TT_LambdaLSquare);
1493 }
1494
moveStateToNextToken(LineState & State,bool DryRun,bool Newline)1495 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State,
1496 bool DryRun, bool Newline) {
1497 assert(State.Stack.size());
1498 const FormatToken &Current = *State.NextToken;
1499 auto &CurrentState = State.Stack.back();
1500
1501 if (Current.is(TT_CSharpGenericTypeConstraint))
1502 CurrentState.IsCSharpGenericTypeConstraint = true;
1503 if (Current.isOneOf(tok::comma, TT_BinaryOperator))
1504 CurrentState.NoLineBreakInOperand = false;
1505 if (Current.isOneOf(TT_InheritanceColon, TT_CSharpGenericTypeConstraintColon))
1506 CurrentState.AvoidBinPacking = true;
1507 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) {
1508 if (CurrentState.FirstLessLess == 0)
1509 CurrentState.FirstLessLess = State.Column;
1510 else
1511 CurrentState.LastOperatorWrapped = Newline;
1512 }
1513 if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless))
1514 CurrentState.LastOperatorWrapped = Newline;
1515 if (Current.is(TT_ConditionalExpr) && Current.Previous &&
1516 Current.Previous->isNot(TT_ConditionalExpr)) {
1517 CurrentState.LastOperatorWrapped = Newline;
1518 }
1519 if (Current.is(TT_ArraySubscriptLSquare) &&
1520 CurrentState.StartOfArraySubscripts == 0) {
1521 CurrentState.StartOfArraySubscripts = State.Column;
1522 }
1523
1524 auto IsWrappedConditional = [](const FormatToken &Tok) {
1525 if (!(Tok.is(TT_ConditionalExpr) && Tok.is(tok::question)))
1526 return false;
1527 if (Tok.MustBreakBefore)
1528 return true;
1529
1530 const FormatToken *Next = Tok.getNextNonComment();
1531 return Next && Next->MustBreakBefore;
1532 };
1533 if (IsWrappedConditional(Current))
1534 CurrentState.IsWrappedConditional = true;
1535 if (Style.BreakBeforeTernaryOperators && Current.is(tok::question))
1536 CurrentState.QuestionColumn = State.Column;
1537 if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) {
1538 const FormatToken *Previous = Current.Previous;
1539 while (Previous && Previous->isTrailingComment())
1540 Previous = Previous->Previous;
1541 if (Previous && Previous->is(tok::question))
1542 CurrentState.QuestionColumn = State.Column;
1543 }
1544 if (!Current.opensScope() && !Current.closesScope() &&
1545 Current.isNot(TT_PointerOrReference)) {
1546 State.LowestLevelOnLine =
1547 std::min(State.LowestLevelOnLine, Current.NestingLevel);
1548 }
1549 if (Current.isMemberAccess())
1550 CurrentState.StartOfFunctionCall = !Current.NextOperator ? 0 : State.Column;
1551 if (Current.is(TT_SelectorName))
1552 CurrentState.ObjCSelectorNameFound = true;
1553 if (Current.is(TT_CtorInitializerColon) &&
1554 Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) {
1555 // Indent 2 from the column, so:
1556 // SomeClass::SomeClass()
1557 // : First(...), ...
1558 // Next(...)
1559 // ^ line up here.
1560 CurrentState.Indent = State.Column + (Style.BreakConstructorInitializers ==
1561 FormatStyle::BCIS_BeforeComma
1562 ? 0
1563 : 2);
1564 CurrentState.NestedBlockIndent = CurrentState.Indent;
1565 if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack) {
1566 CurrentState.AvoidBinPacking = true;
1567 CurrentState.BreakBeforeParameter =
1568 Style.ColumnLimit > 0 &&
1569 Style.PackConstructorInitializers != FormatStyle::PCIS_NextLine &&
1570 Style.PackConstructorInitializers != FormatStyle::PCIS_NextLineOnly;
1571 } else {
1572 CurrentState.BreakBeforeParameter = false;
1573 }
1574 }
1575 if (Current.is(TT_CtorInitializerColon) &&
1576 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) {
1577 CurrentState.Indent =
1578 State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1579 CurrentState.NestedBlockIndent = CurrentState.Indent;
1580 if (Style.PackConstructorInitializers > FormatStyle::PCIS_BinPack)
1581 CurrentState.AvoidBinPacking = true;
1582 else
1583 CurrentState.BreakBeforeParameter = false;
1584 }
1585 if (Current.is(TT_InheritanceColon)) {
1586 CurrentState.Indent =
1587 State.FirstIndent + Style.ConstructorInitializerIndentWidth;
1588 }
1589 if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline)
1590 CurrentState.NestedBlockIndent = State.Column + Current.ColumnWidth + 1;
1591 if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
1592 CurrentState.LastSpace = State.Column;
1593 if (Current.is(TT_RequiresExpression) &&
1594 Style.RequiresExpressionIndentation == FormatStyle::REI_Keyword) {
1595 CurrentState.NestedBlockIndent = State.Column;
1596 }
1597
1598 // Insert scopes created by fake parenthesis.
1599 const FormatToken *Previous = Current.getPreviousNonComment();
1600
1601 // Add special behavior to support a format commonly used for JavaScript
1602 // closures:
1603 // SomeFunction(function() {
1604 // foo();
1605 // bar();
1606 // }, a, b, c);
1607 if (Current.isNot(tok::comment) && !Current.ClosesRequiresClause &&
1608 Previous && Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
1609 Previous->isNot(TT_DictLiteral) && State.Stack.size() > 1 &&
1610 !CurrentState.HasMultipleNestedBlocks) {
1611 if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline)
1612 for (ParenState &PState : llvm::drop_end(State.Stack))
1613 PState.NoLineBreak = true;
1614 State.Stack[State.Stack.size() - 2].NestedBlockInlined = false;
1615 }
1616 if (Previous && (Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr) ||
1617 (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) &&
1618 !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)))) {
1619 CurrentState.NestedBlockInlined =
1620 !Newline && hasNestedBlockInlined(Previous, Current, Style);
1621 }
1622
1623 moveStatePastFakeLParens(State, Newline);
1624 moveStatePastScopeCloser(State);
1625 // Do not use CurrentState here, since the two functions before may change the
1626 // Stack.
1627 bool AllowBreak = !State.Stack.back().NoLineBreak &&
1628 !State.Stack.back().NoLineBreakInOperand;
1629 moveStatePastScopeOpener(State, Newline);
1630 moveStatePastFakeRParens(State);
1631
1632 if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0)
1633 State.StartOfStringLiteral = State.Column + 1;
1634 if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0) {
1635 State.StartOfStringLiteral = State.Column + 1;
1636 } else if (Current.is(TT_TableGenMultiLineString) &&
1637 State.StartOfStringLiteral == 0) {
1638 State.StartOfStringLiteral = State.Column + 1;
1639 } else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0) {
1640 State.StartOfStringLiteral = State.Column;
1641 } else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) &&
1642 !Current.isStringLiteral()) {
1643 State.StartOfStringLiteral = 0;
1644 }
1645
1646 State.Column += Current.ColumnWidth;
1647 State.NextToken = State.NextToken->Next;
1648 // Verilog case labels are on the same unwrapped lines as the statements that
1649 // follow. TokenAnnotator identifies them and sets MustBreakBefore.
1650 // Indentation is taken care of here. A case label can only have 1 statement
1651 // in Verilog, so we don't have to worry about lines that follow.
1652 if (Style.isVerilog() && State.NextToken &&
1653 State.NextToken->MustBreakBefore &&
1654 Keywords.isVerilogEndOfLabel(Current)) {
1655 State.FirstIndent += Style.IndentWidth;
1656 CurrentState.Indent = State.FirstIndent;
1657 }
1658
1659 unsigned Penalty =
1660 handleEndOfLine(Current, State, DryRun, AllowBreak, Newline);
1661
1662 if (Current.Role)
1663 Current.Role->formatFromToken(State, this, DryRun);
1664 // If the previous has a special role, let it consume tokens as appropriate.
1665 // It is necessary to start at the previous token for the only implemented
1666 // role (comma separated list). That way, the decision whether or not to break
1667 // after the "{" is already done and both options are tried and evaluated.
1668 // FIXME: This is ugly, find a better way.
1669 if (Previous && Previous->Role)
1670 Penalty += Previous->Role->formatAfterToken(State, this, DryRun);
1671
1672 return Penalty;
1673 }
1674
moveStatePastFakeLParens(LineState & State,bool Newline)1675 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State,
1676 bool Newline) {
1677 const FormatToken &Current = *State.NextToken;
1678 if (Current.FakeLParens.empty())
1679 return;
1680
1681 const FormatToken *Previous = Current.getPreviousNonComment();
1682
1683 // Don't add extra indentation for the first fake parenthesis after
1684 // 'return', assignments, opening <({[, or requires clauses. The indentation
1685 // for these cases is special cased.
1686 bool SkipFirstExtraIndent =
1687 Previous &&
1688 (Previous->opensScope() ||
1689 Previous->isOneOf(tok::semi, tok::kw_return, TT_RequiresClause) ||
1690 (Previous->getPrecedence() == prec::Assignment &&
1691 Style.AlignOperands != FormatStyle::OAS_DontAlign) ||
1692 Previous->is(TT_ObjCMethodExpr));
1693 for (const auto &PrecedenceLevel : llvm::reverse(Current.FakeLParens)) {
1694 const auto &CurrentState = State.Stack.back();
1695 ParenState NewParenState = CurrentState;
1696 NewParenState.Tok = nullptr;
1697 NewParenState.ContainsLineBreak = false;
1698 NewParenState.LastOperatorWrapped = true;
1699 NewParenState.IsChainedConditional = false;
1700 NewParenState.IsWrappedConditional = false;
1701 NewParenState.UnindentOperator = false;
1702 NewParenState.NoLineBreak =
1703 NewParenState.NoLineBreak || CurrentState.NoLineBreakInOperand;
1704
1705 // Don't propagate AvoidBinPacking into subexpressions of arg/param lists.
1706 if (PrecedenceLevel > prec::Comma)
1707 NewParenState.AvoidBinPacking = false;
1708
1709 // Indent from 'LastSpace' unless these are fake parentheses encapsulating
1710 // a builder type call after 'return' or, if the alignment after opening
1711 // brackets is disabled.
1712 if (!Current.isTrailingComment() &&
1713 (Style.AlignOperands != FormatStyle::OAS_DontAlign ||
1714 PrecedenceLevel < prec::Assignment) &&
1715 (!Previous || Previous->isNot(tok::kw_return) ||
1716 (Style.Language != FormatStyle::LK_Java && PrecedenceLevel > 0)) &&
1717 (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign ||
1718 PrecedenceLevel > prec::Comma || Current.NestingLevel == 0) &&
1719 (!Style.isTableGen() ||
1720 (Previous && Previous->isOneOf(TT_TableGenDAGArgListComma,
1721 TT_TableGenDAGArgListCommaToBreak)))) {
1722 NewParenState.Indent = std::max(
1723 std::max(State.Column, NewParenState.Indent), CurrentState.LastSpace);
1724 }
1725
1726 // Special case for generic selection expressions, its comma-separated
1727 // expressions are not aligned to the opening paren like regular calls, but
1728 // rather continuation-indented relative to the _Generic keyword.
1729 if (Previous && Previous->endsSequence(tok::l_paren, tok::kw__Generic) &&
1730 State.Stack.size() > 1) {
1731 NewParenState.Indent = State.Stack[State.Stack.size() - 2].Indent +
1732 Style.ContinuationIndentWidth;
1733 }
1734
1735 if ((shouldUnindentNextOperator(Current) ||
1736 (Previous &&
1737 (PrecedenceLevel == prec::Conditional &&
1738 Previous->is(tok::question) && Previous->is(TT_ConditionalExpr)))) &&
1739 !Newline) {
1740 // If BreakBeforeBinaryOperators is set, un-indent a bit to account for
1741 // the operator and keep the operands aligned.
1742 if (Style.AlignOperands == FormatStyle::OAS_AlignAfterOperator)
1743 NewParenState.UnindentOperator = true;
1744 // Mark indentation as alignment if the expression is aligned.
1745 if (Style.AlignOperands != FormatStyle::OAS_DontAlign)
1746 NewParenState.IsAligned = true;
1747 }
1748
1749 // Do not indent relative to the fake parentheses inserted for "." or "->".
1750 // This is a special case to make the following to statements consistent:
1751 // OuterFunction(InnerFunctionCall( // break
1752 // ParameterToInnerFunction));
1753 // OuterFunction(SomeObject.InnerFunctionCall( // break
1754 // ParameterToInnerFunction));
1755 if (PrecedenceLevel > prec::Unknown)
1756 NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column);
1757 if (PrecedenceLevel != prec::Conditional &&
1758 Current.isNot(TT_UnaryOperator) &&
1759 Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign) {
1760 NewParenState.StartOfFunctionCall = State.Column;
1761 }
1762
1763 // Indent conditional expressions, unless they are chained "else-if"
1764 // conditionals. Never indent expression where the 'operator' is ',', ';' or
1765 // an assignment (i.e. *I <= prec::Assignment) as those have different
1766 // indentation rules. Indent other expression, unless the indentation needs
1767 // to be skipped.
1768 if (PrecedenceLevel == prec::Conditional && Previous &&
1769 Previous->is(tok::colon) && Previous->is(TT_ConditionalExpr) &&
1770 &PrecedenceLevel == &Current.FakeLParens.back() &&
1771 !CurrentState.IsWrappedConditional) {
1772 NewParenState.IsChainedConditional = true;
1773 NewParenState.UnindentOperator = State.Stack.back().UnindentOperator;
1774 } else if (PrecedenceLevel == prec::Conditional ||
1775 (!SkipFirstExtraIndent && PrecedenceLevel > prec::Assignment &&
1776 !Current.isTrailingComment())) {
1777 NewParenState.Indent += Style.ContinuationIndentWidth;
1778 }
1779 if ((Previous && !Previous->opensScope()) || PrecedenceLevel != prec::Comma)
1780 NewParenState.BreakBeforeParameter = false;
1781 State.Stack.push_back(NewParenState);
1782 SkipFirstExtraIndent = false;
1783 }
1784 }
1785
moveStatePastFakeRParens(LineState & State)1786 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) {
1787 for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) {
1788 unsigned VariablePos = State.Stack.back().VariablePos;
1789 if (State.Stack.size() == 1) {
1790 // Do not pop the last element.
1791 break;
1792 }
1793 State.Stack.pop_back();
1794 State.Stack.back().VariablePos = VariablePos;
1795 }
1796
1797 if (State.NextToken->ClosesRequiresClause && Style.IndentRequiresClause) {
1798 // Remove the indentation of the requires clauses (which is not in Indent,
1799 // but in LastSpace).
1800 State.Stack.back().LastSpace -= Style.IndentWidth;
1801 }
1802 }
1803
moveStatePastScopeOpener(LineState & State,bool Newline)1804 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State,
1805 bool Newline) {
1806 const FormatToken &Current = *State.NextToken;
1807 if (!Current.opensScope())
1808 return;
1809
1810 const auto &CurrentState = State.Stack.back();
1811
1812 // Don't allow '<' or '(' in C# generic type constraints to start new scopes.
1813 if (Current.isOneOf(tok::less, tok::l_paren) &&
1814 CurrentState.IsCSharpGenericTypeConstraint) {
1815 return;
1816 }
1817
1818 if (Current.MatchingParen && Current.is(BK_Block)) {
1819 moveStateToNewBlock(State, Newline);
1820 return;
1821 }
1822
1823 unsigned NewIndent;
1824 unsigned LastSpace = CurrentState.LastSpace;
1825 bool AvoidBinPacking;
1826 bool BreakBeforeParameter = false;
1827 unsigned NestedBlockIndent = std::max(CurrentState.StartOfFunctionCall,
1828 CurrentState.NestedBlockIndent);
1829 if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) ||
1830 opensProtoMessageField(Current, Style)) {
1831 if (Current.opensBlockOrBlockTypeList(Style)) {
1832 NewIndent = Style.IndentWidth +
1833 std::min(State.Column, CurrentState.NestedBlockIndent);
1834 } else if (Current.is(tok::l_brace)) {
1835 NewIndent =
1836 CurrentState.LastSpace + Style.BracedInitializerIndentWidth.value_or(
1837 Style.ContinuationIndentWidth);
1838 } else {
1839 NewIndent = CurrentState.LastSpace + Style.ContinuationIndentWidth;
1840 }
1841 const FormatToken *NextNonComment = Current.getNextNonComment();
1842 bool EndsInComma = Current.MatchingParen &&
1843 Current.MatchingParen->Previous &&
1844 Current.MatchingParen->Previous->is(tok::comma);
1845 AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) ||
1846 Style.isProto() || !Style.BinPackArguments ||
1847 (NextNonComment && NextNonComment->isOneOf(
1848 TT_DesignatedInitializerPeriod,
1849 TT_DesignatedInitializerLSquare));
1850 BreakBeforeParameter = EndsInComma;
1851 if (Current.ParameterCount > 1)
1852 NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1);
1853 } else {
1854 NewIndent =
1855 Style.ContinuationIndentWidth +
1856 std::max(CurrentState.LastSpace, CurrentState.StartOfFunctionCall);
1857
1858 if (Style.isTableGen() && Current.is(TT_TableGenDAGArgOpenerToBreak) &&
1859 Style.TableGenBreakInsideDAGArg == FormatStyle::DAS_BreakElements) {
1860 // For the case the next token is a TableGen DAGArg operator identifier
1861 // that is not marked to have a line break after it.
1862 // In this case the option DAS_BreakElements requires to align the
1863 // DAGArg elements to the operator.
1864 const FormatToken *Next = Current.Next;
1865 if (Next && Next->is(TT_TableGenDAGArgOperatorID))
1866 NewIndent = State.Column + Next->TokenText.size() + 2;
1867 }
1868
1869 // Ensure that different different brackets force relative alignment, e.g.:
1870 // void SomeFunction(vector< // break
1871 // int> v);
1872 // FIXME: We likely want to do this for more combinations of brackets.
1873 if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) {
1874 NewIndent = std::max(NewIndent, CurrentState.Indent);
1875 LastSpace = std::max(LastSpace, CurrentState.Indent);
1876 }
1877
1878 bool EndsInComma =
1879 Current.MatchingParen &&
1880 Current.MatchingParen->getPreviousNonComment() &&
1881 Current.MatchingParen->getPreviousNonComment()->is(tok::comma);
1882
1883 // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters
1884 // for backwards compatibility.
1885 bool ObjCBinPackProtocolList =
1886 (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto &&
1887 Style.BinPackParameters) ||
1888 Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always;
1889
1890 bool BinPackDeclaration =
1891 (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) ||
1892 (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList);
1893
1894 bool GenericSelection =
1895 Current.getPreviousNonComment() &&
1896 Current.getPreviousNonComment()->is(tok::kw__Generic);
1897
1898 AvoidBinPacking =
1899 (CurrentState.IsCSharpGenericTypeConstraint) || GenericSelection ||
1900 (Style.isJavaScript() && EndsInComma) ||
1901 (State.Line->MustBeDeclaration && !BinPackDeclaration) ||
1902 (!State.Line->MustBeDeclaration && !Style.BinPackArguments) ||
1903 (Style.ExperimentalAutoDetectBinPacking &&
1904 (Current.is(PPK_OnePerLine) ||
1905 (!BinPackInconclusiveFunctions && Current.is(PPK_Inconclusive))));
1906
1907 if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen &&
1908 Style.ObjCBreakBeforeNestedBlockParam) {
1909 if (Style.ColumnLimit) {
1910 // If this '[' opens an ObjC call, determine whether all parameters fit
1911 // into one line and put one per line if they don't.
1912 if (getLengthToMatchingParen(Current, State.Stack) + State.Column >
1913 getColumnLimit(State)) {
1914 BreakBeforeParameter = true;
1915 }
1916 } else {
1917 // For ColumnLimit = 0, we have to figure out whether there is or has to
1918 // be a line break within this call.
1919 for (const FormatToken *Tok = &Current;
1920 Tok && Tok != Current.MatchingParen; Tok = Tok->Next) {
1921 if (Tok->MustBreakBefore ||
1922 (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) {
1923 BreakBeforeParameter = true;
1924 break;
1925 }
1926 }
1927 }
1928 }
1929
1930 if (Style.isJavaScript() && EndsInComma)
1931 BreakBeforeParameter = true;
1932 }
1933 // Generally inherit NoLineBreak from the current scope to nested scope.
1934 // However, don't do this for non-empty nested blocks, dict literals and
1935 // array literals as these follow different indentation rules.
1936 bool NoLineBreak =
1937 Current.Children.empty() &&
1938 !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) &&
1939 (CurrentState.NoLineBreak || CurrentState.NoLineBreakInOperand ||
1940 (Current.is(TT_TemplateOpener) &&
1941 CurrentState.ContainsUnwrappedBuilder));
1942 State.Stack.push_back(
1943 ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak));
1944 auto &NewState = State.Stack.back();
1945 NewState.NestedBlockIndent = NestedBlockIndent;
1946 NewState.BreakBeforeParameter = BreakBeforeParameter;
1947 NewState.HasMultipleNestedBlocks = (Current.BlockParameterCount > 1);
1948
1949 if (Style.BraceWrapping.BeforeLambdaBody && Current.Next &&
1950 Current.is(tok::l_paren)) {
1951 // Search for any parameter that is a lambda.
1952 FormatToken const *next = Current.Next;
1953 while (next) {
1954 if (next->is(TT_LambdaLSquare)) {
1955 NewState.HasMultipleNestedBlocks = true;
1956 break;
1957 }
1958 next = next->Next;
1959 }
1960 }
1961
1962 NewState.IsInsideObjCArrayLiteral = Current.is(TT_ArrayInitializerLSquare) &&
1963 Current.Previous &&
1964 Current.Previous->is(tok::at);
1965 }
1966
moveStatePastScopeCloser(LineState & State)1967 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) {
1968 const FormatToken &Current = *State.NextToken;
1969 if (!Current.closesScope())
1970 return;
1971
1972 // If we encounter a closing ), ], } or >, we can remove a level from our
1973 // stacks.
1974 if (State.Stack.size() > 1 &&
1975 (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) ||
1976 (Current.is(tok::r_brace) && State.NextToken != State.Line->First) ||
1977 State.NextToken->is(TT_TemplateCloser) ||
1978 State.NextToken->is(TT_TableGenListCloser) ||
1979 (Current.is(tok::greater) && Current.is(TT_DictLiteral)))) {
1980 State.Stack.pop_back();
1981 }
1982
1983 auto &CurrentState = State.Stack.back();
1984
1985 // Reevaluate whether ObjC message arguments fit into one line.
1986 // If a receiver spans multiple lines, e.g.:
1987 // [[object block:^{
1988 // return 42;
1989 // }] a:42 b:42];
1990 // BreakBeforeParameter is calculated based on an incorrect assumption
1991 // (it is checked whether the whole expression fits into one line without
1992 // considering a line break inside a message receiver).
1993 // We check whether arguments fit after receiver scope closer (into the same
1994 // line).
1995 if (CurrentState.BreakBeforeParameter && Current.MatchingParen &&
1996 Current.MatchingParen->Previous) {
1997 const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous;
1998 if (CurrentScopeOpener.is(TT_ObjCMethodExpr) &&
1999 CurrentScopeOpener.MatchingParen) {
2000 int NecessarySpaceInLine =
2001 getLengthToMatchingParen(CurrentScopeOpener, State.Stack) +
2002 CurrentScopeOpener.TotalLength - Current.TotalLength - 1;
2003 if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <=
2004 Style.ColumnLimit) {
2005 CurrentState.BreakBeforeParameter = false;
2006 }
2007 }
2008 }
2009
2010 if (Current.is(tok::r_square)) {
2011 // If this ends the array subscript expr, reset the corresponding value.
2012 const FormatToken *NextNonComment = Current.getNextNonComment();
2013 if (NextNonComment && NextNonComment->isNot(tok::l_square))
2014 CurrentState.StartOfArraySubscripts = 0;
2015 }
2016 }
2017
moveStateToNewBlock(LineState & State,bool NewLine)2018 void ContinuationIndenter::moveStateToNewBlock(LineState &State, bool NewLine) {
2019 if (Style.LambdaBodyIndentation == FormatStyle::LBI_OuterScope &&
2020 State.NextToken->is(TT_LambdaLBrace) &&
2021 !State.Line->MightBeFunctionDecl) {
2022 State.Stack.back().NestedBlockIndent = State.FirstIndent;
2023 }
2024 unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent;
2025 // ObjC block sometimes follow special indentation rules.
2026 unsigned NewIndent =
2027 NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace)
2028 ? Style.ObjCBlockIndentWidth
2029 : Style.IndentWidth);
2030
2031 // Even when wrapping before lambda body, the left brace can still be added to
2032 // the same line. This occurs when checking whether the whole lambda body can
2033 // go on a single line. In this case we have to make sure there are no line
2034 // breaks in the body, otherwise we could just end up with a regular lambda
2035 // body without the brace wrapped.
2036 bool NoLineBreak = Style.BraceWrapping.BeforeLambdaBody && !NewLine &&
2037 State.NextToken->is(TT_LambdaLBrace);
2038
2039 State.Stack.push_back(ParenState(State.NextToken, NewIndent,
2040 State.Stack.back().LastSpace,
2041 /*AvoidBinPacking=*/true, NoLineBreak));
2042 State.Stack.back().NestedBlockIndent = NestedBlockIndent;
2043 State.Stack.back().BreakBeforeParameter = true;
2044 }
2045
getLastLineEndColumn(StringRef Text,unsigned StartColumn,unsigned TabWidth,encoding::Encoding Encoding)2046 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn,
2047 unsigned TabWidth,
2048 encoding::Encoding Encoding) {
2049 size_t LastNewlinePos = Text.find_last_of("\n");
2050 if (LastNewlinePos == StringRef::npos) {
2051 return StartColumn +
2052 encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding);
2053 } else {
2054 return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos),
2055 /*StartColumn=*/0, TabWidth, Encoding);
2056 }
2057 }
2058
reformatRawStringLiteral(const FormatToken & Current,LineState & State,const FormatStyle & RawStringStyle,bool DryRun,bool Newline)2059 unsigned ContinuationIndenter::reformatRawStringLiteral(
2060 const FormatToken &Current, LineState &State,
2061 const FormatStyle &RawStringStyle, bool DryRun, bool Newline) {
2062 unsigned StartColumn = State.Column - Current.ColumnWidth;
2063 StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText);
2064 StringRef NewDelimiter =
2065 getCanonicalRawStringDelimiter(Style, RawStringStyle.Language);
2066 if (NewDelimiter.empty())
2067 NewDelimiter = OldDelimiter;
2068 // The text of a raw string is between the leading 'R"delimiter(' and the
2069 // trailing 'delimiter)"'.
2070 unsigned OldPrefixSize = 3 + OldDelimiter.size();
2071 unsigned OldSuffixSize = 2 + OldDelimiter.size();
2072 // We create a virtual text environment which expects a null-terminated
2073 // string, so we cannot use StringRef.
2074 std::string RawText = std::string(
2075 Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize));
2076 if (NewDelimiter != OldDelimiter) {
2077 // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the
2078 // raw string.
2079 std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str();
2080 if (StringRef(RawText).contains(CanonicalDelimiterSuffix))
2081 NewDelimiter = OldDelimiter;
2082 }
2083
2084 unsigned NewPrefixSize = 3 + NewDelimiter.size();
2085 unsigned NewSuffixSize = 2 + NewDelimiter.size();
2086
2087 // The first start column is the column the raw text starts after formatting.
2088 unsigned FirstStartColumn = StartColumn + NewPrefixSize;
2089
2090 // The next start column is the intended indentation a line break inside
2091 // the raw string at level 0. It is determined by the following rules:
2092 // - if the content starts on newline, it is one level more than the current
2093 // indent, and
2094 // - if the content does not start on a newline, it is the first start
2095 // column.
2096 // These rules have the advantage that the formatted content both does not
2097 // violate the rectangle rule and visually flows within the surrounding
2098 // source.
2099 bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n';
2100 // If this token is the last parameter (checked by looking if it's followed by
2101 // `)` and is not on a newline, the base the indent off the line's nested
2102 // block indent. Otherwise, base the indent off the arguments indent, so we
2103 // can achieve:
2104 //
2105 // fffffffffff(1, 2, 3, R"pb(
2106 // key1: 1 #
2107 // key2: 2)pb");
2108 //
2109 // fffffffffff(1, 2, 3,
2110 // R"pb(
2111 // key1: 1 #
2112 // key2: 2
2113 // )pb");
2114 //
2115 // fffffffffff(1, 2, 3,
2116 // R"pb(
2117 // key1: 1 #
2118 // key2: 2
2119 // )pb",
2120 // 5);
2121 unsigned CurrentIndent =
2122 (!Newline && Current.Next && Current.Next->is(tok::r_paren))
2123 ? State.Stack.back().NestedBlockIndent
2124 : State.Stack.back().Indent;
2125 unsigned NextStartColumn = ContentStartsOnNewline
2126 ? CurrentIndent + Style.IndentWidth
2127 : FirstStartColumn;
2128
2129 // The last start column is the column the raw string suffix starts if it is
2130 // put on a newline.
2131 // The last start column is the intended indentation of the raw string postfix
2132 // if it is put on a newline. It is determined by the following rules:
2133 // - if the raw string prefix starts on a newline, it is the column where
2134 // that raw string prefix starts, and
2135 // - if the raw string prefix does not start on a newline, it is the current
2136 // indent.
2137 unsigned LastStartColumn =
2138 Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent;
2139
2140 std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat(
2141 RawStringStyle, RawText, {tooling::Range(0, RawText.size())},
2142 FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>",
2143 /*Status=*/nullptr);
2144
2145 auto NewCode = applyAllReplacements(RawText, Fixes.first);
2146 tooling::Replacements NoFixes;
2147 if (!NewCode)
2148 return addMultilineToken(Current, State);
2149 if (!DryRun) {
2150 if (NewDelimiter != OldDelimiter) {
2151 // In 'R"delimiter(...', the delimiter starts 2 characters after the start
2152 // of the token.
2153 SourceLocation PrefixDelimiterStart =
2154 Current.Tok.getLocation().getLocWithOffset(2);
2155 auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement(
2156 SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2157 if (PrefixErr) {
2158 llvm::errs()
2159 << "Failed to update the prefix delimiter of a raw string: "
2160 << llvm::toString(std::move(PrefixErr)) << "\n";
2161 }
2162 // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at
2163 // position length - 1 - |delimiter|.
2164 SourceLocation SuffixDelimiterStart =
2165 Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() -
2166 1 - OldDelimiter.size());
2167 auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement(
2168 SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter));
2169 if (SuffixErr) {
2170 llvm::errs()
2171 << "Failed to update the suffix delimiter of a raw string: "
2172 << llvm::toString(std::move(SuffixErr)) << "\n";
2173 }
2174 }
2175 SourceLocation OriginLoc =
2176 Current.Tok.getLocation().getLocWithOffset(OldPrefixSize);
2177 for (const tooling::Replacement &Fix : Fixes.first) {
2178 auto Err = Whitespaces.addReplacement(tooling::Replacement(
2179 SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()),
2180 Fix.getLength(), Fix.getReplacementText()));
2181 if (Err) {
2182 llvm::errs() << "Failed to reformat raw string: "
2183 << llvm::toString(std::move(Err)) << "\n";
2184 }
2185 }
2186 }
2187 unsigned RawLastLineEndColumn = getLastLineEndColumn(
2188 *NewCode, FirstStartColumn, Style.TabWidth, Encoding);
2189 State.Column = RawLastLineEndColumn + NewSuffixSize;
2190 // Since we're updating the column to after the raw string literal here, we
2191 // have to manually add the penalty for the prefix R"delim( over the column
2192 // limit.
2193 unsigned PrefixExcessCharacters =
2194 StartColumn + NewPrefixSize > Style.ColumnLimit
2195 ? StartColumn + NewPrefixSize - Style.ColumnLimit
2196 : 0;
2197 bool IsMultiline =
2198 ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos);
2199 if (IsMultiline) {
2200 // Break before further function parameters on all levels.
2201 for (ParenState &Paren : State.Stack)
2202 Paren.BreakBeforeParameter = true;
2203 }
2204 return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter;
2205 }
2206
addMultilineToken(const FormatToken & Current,LineState & State)2207 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current,
2208 LineState &State) {
2209 // Break before further function parameters on all levels.
2210 for (ParenState &Paren : State.Stack)
2211 Paren.BreakBeforeParameter = true;
2212
2213 unsigned ColumnsUsed = State.Column;
2214 // We can only affect layout of the first and the last line, so the penalty
2215 // for all other lines is constant, and we ignore it.
2216 State.Column = Current.LastLineColumnWidth;
2217
2218 if (ColumnsUsed > getColumnLimit(State))
2219 return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State));
2220 return 0;
2221 }
2222
handleEndOfLine(const FormatToken & Current,LineState & State,bool DryRun,bool AllowBreak,bool Newline)2223 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current,
2224 LineState &State, bool DryRun,
2225 bool AllowBreak, bool Newline) {
2226 unsigned Penalty = 0;
2227 // Compute the raw string style to use in case this is a raw string literal
2228 // that can be reformatted.
2229 auto RawStringStyle = getRawStringStyle(Current, State);
2230 if (RawStringStyle && !Current.Finalized) {
2231 Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun,
2232 Newline);
2233 } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) {
2234 // Don't break multi-line tokens other than block comments and raw string
2235 // literals. Instead, just update the state.
2236 Penalty = addMultilineToken(Current, State);
2237 } else if (State.Line->Type != LT_ImportStatement) {
2238 // We generally don't break import statements.
2239 LineState OriginalState = State;
2240
2241 // Whether we force the reflowing algorithm to stay strictly within the
2242 // column limit.
2243 bool Strict = false;
2244 // Whether the first non-strict attempt at reflowing did intentionally
2245 // exceed the column limit.
2246 bool Exceeded = false;
2247 std::tie(Penalty, Exceeded) = breakProtrudingToken(
2248 Current, State, AllowBreak, /*DryRun=*/true, Strict);
2249 if (Exceeded) {
2250 // If non-strict reflowing exceeds the column limit, try whether strict
2251 // reflowing leads to an overall lower penalty.
2252 LineState StrictState = OriginalState;
2253 unsigned StrictPenalty =
2254 breakProtrudingToken(Current, StrictState, AllowBreak,
2255 /*DryRun=*/true, /*Strict=*/true)
2256 .first;
2257 Strict = StrictPenalty <= Penalty;
2258 if (Strict) {
2259 Penalty = StrictPenalty;
2260 State = StrictState;
2261 }
2262 }
2263 if (!DryRun) {
2264 // If we're not in dry-run mode, apply the changes with the decision on
2265 // strictness made above.
2266 breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false,
2267 Strict);
2268 }
2269 }
2270 if (State.Column > getColumnLimit(State)) {
2271 unsigned ExcessCharacters = State.Column - getColumnLimit(State);
2272 Penalty += Style.PenaltyExcessCharacter * ExcessCharacters;
2273 }
2274 return Penalty;
2275 }
2276
2277 // Returns the enclosing function name of a token, or the empty string if not
2278 // found.
getEnclosingFunctionName(const FormatToken & Current)2279 static StringRef getEnclosingFunctionName(const FormatToken &Current) {
2280 // Look for: 'function(' or 'function<templates>(' before Current.
2281 auto Tok = Current.getPreviousNonComment();
2282 if (!Tok || Tok->isNot(tok::l_paren))
2283 return "";
2284 Tok = Tok->getPreviousNonComment();
2285 if (!Tok)
2286 return "";
2287 if (Tok->is(TT_TemplateCloser)) {
2288 Tok = Tok->MatchingParen;
2289 if (Tok)
2290 Tok = Tok->getPreviousNonComment();
2291 }
2292 if (!Tok || Tok->isNot(tok::identifier))
2293 return "";
2294 return Tok->TokenText;
2295 }
2296
2297 std::optional<FormatStyle>
getRawStringStyle(const FormatToken & Current,const LineState & State)2298 ContinuationIndenter::getRawStringStyle(const FormatToken &Current,
2299 const LineState &State) {
2300 if (!Current.isStringLiteral())
2301 return std::nullopt;
2302 auto Delimiter = getRawStringDelimiter(Current.TokenText);
2303 if (!Delimiter)
2304 return std::nullopt;
2305 auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter);
2306 if (!RawStringStyle && Delimiter->empty()) {
2307 RawStringStyle = RawStringFormats.getEnclosingFunctionStyle(
2308 getEnclosingFunctionName(Current));
2309 }
2310 if (!RawStringStyle)
2311 return std::nullopt;
2312 RawStringStyle->ColumnLimit = getColumnLimit(State);
2313 return RawStringStyle;
2314 }
2315
2316 std::unique_ptr<BreakableToken>
createBreakableToken(const FormatToken & Current,LineState & State,bool AllowBreak)2317 ContinuationIndenter::createBreakableToken(const FormatToken &Current,
2318 LineState &State, bool AllowBreak) {
2319 unsigned StartColumn = State.Column - Current.ColumnWidth;
2320 if (Current.isStringLiteral()) {
2321 // Strings in JSON cannot be broken. Breaking strings in JavaScript is
2322 // disabled for now.
2323 if (Style.isJson() || Style.isJavaScript() || !Style.BreakStringLiterals ||
2324 !AllowBreak) {
2325 return nullptr;
2326 }
2327
2328 // Don't break string literals inside preprocessor directives (except for
2329 // #define directives, as their contents are stored in separate lines and
2330 // are not affected by this check).
2331 // This way we avoid breaking code with line directives and unknown
2332 // preprocessor directives that contain long string literals.
2333 if (State.Line->Type == LT_PreprocessorDirective)
2334 return nullptr;
2335 // Exempts unterminated string literals from line breaking. The user will
2336 // likely want to terminate the string before any line breaking is done.
2337 if (Current.IsUnterminatedLiteral)
2338 return nullptr;
2339 // Don't break string literals inside Objective-C array literals (doing so
2340 // raises the warning -Wobjc-string-concatenation).
2341 if (State.Stack.back().IsInsideObjCArrayLiteral)
2342 return nullptr;
2343
2344 // The "DPI"/"DPI-C" in SystemVerilog direct programming interface
2345 // imports/exports cannot be split, e.g.
2346 // `import "DPI" function foo();`
2347 // FIXME: make this use same infra as C++ import checks
2348 if (Style.isVerilog() && Current.Previous &&
2349 Current.Previous->isOneOf(tok::kw_export, Keywords.kw_import)) {
2350 return nullptr;
2351 }
2352 StringRef Text = Current.TokenText;
2353
2354 // We need this to address the case where there is an unbreakable tail only
2355 // if certain other formatting decisions have been taken. The
2356 // UnbreakableTailLength of Current is an overapproximation in that case and
2357 // we need to be correct here.
2358 unsigned UnbreakableTailLength = (State.NextToken && canBreak(State))
2359 ? 0
2360 : Current.UnbreakableTailLength;
2361
2362 if (Style.isVerilog() || Style.Language == FormatStyle::LK_Java ||
2363 Style.isJavaScript() || Style.isCSharp()) {
2364 BreakableStringLiteralUsingOperators::QuoteStyleType QuoteStyle;
2365 if (Style.isJavaScript() && Text.starts_with("'") &&
2366 Text.ends_with("'")) {
2367 QuoteStyle = BreakableStringLiteralUsingOperators::SingleQuotes;
2368 } else if (Style.isCSharp() && Text.starts_with("@\"") &&
2369 Text.ends_with("\"")) {
2370 QuoteStyle = BreakableStringLiteralUsingOperators::AtDoubleQuotes;
2371 } else if (Text.starts_with("\"") && Text.ends_with("\"")) {
2372 QuoteStyle = BreakableStringLiteralUsingOperators::DoubleQuotes;
2373 } else {
2374 return nullptr;
2375 }
2376 return std::make_unique<BreakableStringLiteralUsingOperators>(
2377 Current, QuoteStyle,
2378 /*UnindentPlus=*/shouldUnindentNextOperator(Current), StartColumn,
2379 UnbreakableTailLength, State.Line->InPPDirective, Encoding, Style);
2380 }
2381
2382 StringRef Prefix;
2383 StringRef Postfix;
2384 // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'.
2385 // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to
2386 // reduce the overhead) for each FormatToken, which is a string, so that we
2387 // don't run multiple checks here on the hot path.
2388 if ((Text.ends_with(Postfix = "\"") &&
2389 (Text.starts_with(Prefix = "@\"") || Text.starts_with(Prefix = "\"") ||
2390 Text.starts_with(Prefix = "u\"") ||
2391 Text.starts_with(Prefix = "U\"") ||
2392 Text.starts_with(Prefix = "u8\"") ||
2393 Text.starts_with(Prefix = "L\""))) ||
2394 (Text.starts_with(Prefix = "_T(\"") &&
2395 Text.ends_with(Postfix = "\")"))) {
2396 return std::make_unique<BreakableStringLiteral>(
2397 Current, StartColumn, Prefix, Postfix, UnbreakableTailLength,
2398 State.Line->InPPDirective, Encoding, Style);
2399 }
2400 } else if (Current.is(TT_BlockComment)) {
2401 if (!Style.ReflowComments ||
2402 // If a comment token switches formatting, like
2403 // /* clang-format on */, we don't want to break it further,
2404 // but we may still want to adjust its indentation.
2405 switchesFormatting(Current)) {
2406 return nullptr;
2407 }
2408 return std::make_unique<BreakableBlockComment>(
2409 Current, StartColumn, Current.OriginalColumn, !Current.Previous,
2410 State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF());
2411 } else if (Current.is(TT_LineComment) &&
2412 (!Current.Previous ||
2413 Current.Previous->isNot(TT_ImplicitStringLiteral))) {
2414 bool RegularComments = [&]() {
2415 for (const FormatToken *T = &Current; T && T->is(TT_LineComment);
2416 T = T->Next) {
2417 if (!(T->TokenText.starts_with("//") || T->TokenText.starts_with("#")))
2418 return false;
2419 }
2420 return true;
2421 }();
2422 if (!Style.ReflowComments ||
2423 CommentPragmasRegex.match(Current.TokenText.substr(2)) ||
2424 switchesFormatting(Current) || !RegularComments) {
2425 return nullptr;
2426 }
2427 return std::make_unique<BreakableLineCommentSection>(
2428 Current, StartColumn, /*InPPDirective=*/false, Encoding, Style);
2429 }
2430 return nullptr;
2431 }
2432
2433 std::pair<unsigned, bool>
breakProtrudingToken(const FormatToken & Current,LineState & State,bool AllowBreak,bool DryRun,bool Strict)2434 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current,
2435 LineState &State, bool AllowBreak,
2436 bool DryRun, bool Strict) {
2437 std::unique_ptr<const BreakableToken> Token =
2438 createBreakableToken(Current, State, AllowBreak);
2439 if (!Token)
2440 return {0, false};
2441 assert(Token->getLineCount() > 0);
2442 unsigned ColumnLimit = getColumnLimit(State);
2443 if (Current.is(TT_LineComment)) {
2444 // We don't insert backslashes when breaking line comments.
2445 ColumnLimit = Style.ColumnLimit;
2446 }
2447 if (ColumnLimit == 0) {
2448 // To make the rest of the function easier set the column limit to the
2449 // maximum, if there should be no limit.
2450 ColumnLimit = std::numeric_limits<decltype(ColumnLimit)>::max();
2451 }
2452 if (Current.UnbreakableTailLength >= ColumnLimit)
2453 return {0, false};
2454 // ColumnWidth was already accounted into State.Column before calling
2455 // breakProtrudingToken.
2456 unsigned StartColumn = State.Column - Current.ColumnWidth;
2457 unsigned NewBreakPenalty = Current.isStringLiteral()
2458 ? Style.PenaltyBreakString
2459 : Style.PenaltyBreakComment;
2460 // Stores whether we intentionally decide to let a line exceed the column
2461 // limit.
2462 bool Exceeded = false;
2463 // Stores whether we introduce a break anywhere in the token.
2464 bool BreakInserted = Token->introducesBreakBeforeToken();
2465 // Store whether we inserted a new line break at the end of the previous
2466 // logical line.
2467 bool NewBreakBefore = false;
2468 // We use a conservative reflowing strategy. Reflow starts after a line is
2469 // broken or the corresponding whitespace compressed. Reflow ends as soon as a
2470 // line that doesn't get reflown with the previous line is reached.
2471 bool Reflow = false;
2472 // Keep track of where we are in the token:
2473 // Where we are in the content of the current logical line.
2474 unsigned TailOffset = 0;
2475 // The column number we're currently at.
2476 unsigned ContentStartColumn =
2477 Token->getContentStartColumn(0, /*Break=*/false);
2478 // The number of columns left in the current logical line after TailOffset.
2479 unsigned RemainingTokenColumns =
2480 Token->getRemainingLength(0, TailOffset, ContentStartColumn);
2481 // Adapt the start of the token, for example indent.
2482 if (!DryRun)
2483 Token->adaptStartOfLine(0, Whitespaces);
2484
2485 unsigned ContentIndent = 0;
2486 unsigned Penalty = 0;
2487 LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column "
2488 << StartColumn << ".\n");
2489 for (unsigned LineIndex = 0, EndIndex = Token->getLineCount();
2490 LineIndex != EndIndex; ++LineIndex) {
2491 LLVM_DEBUG(llvm::dbgs()
2492 << " Line: " << LineIndex << " (Reflow: " << Reflow << ")\n");
2493 NewBreakBefore = false;
2494 // If we did reflow the previous line, we'll try reflowing again. Otherwise
2495 // we'll start reflowing if the current line is broken or whitespace is
2496 // compressed.
2497 bool TryReflow = Reflow;
2498 // Break the current token until we can fit the rest of the line.
2499 while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2500 LLVM_DEBUG(llvm::dbgs() << " Over limit, need: "
2501 << (ContentStartColumn + RemainingTokenColumns)
2502 << ", space: " << ColumnLimit
2503 << ", reflown prefix: " << ContentStartColumn
2504 << ", offset in line: " << TailOffset << "\n");
2505 // If the current token doesn't fit, find the latest possible split in the
2506 // current line so that breaking at it will be under the column limit.
2507 // FIXME: Use the earliest possible split while reflowing to correctly
2508 // compress whitespace within a line.
2509 BreakableToken::Split Split =
2510 Token->getSplit(LineIndex, TailOffset, ColumnLimit,
2511 ContentStartColumn, CommentPragmasRegex);
2512 if (Split.first == StringRef::npos) {
2513 // No break opportunity - update the penalty and continue with the next
2514 // logical line.
2515 if (LineIndex < EndIndex - 1) {
2516 // The last line's penalty is handled in addNextStateToQueue() or when
2517 // calling replaceWhitespaceAfterLastLine below.
2518 Penalty += Style.PenaltyExcessCharacter *
2519 (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2520 }
2521 LLVM_DEBUG(llvm::dbgs() << " No break opportunity.\n");
2522 break;
2523 }
2524 assert(Split.first != 0);
2525
2526 if (Token->supportsReflow()) {
2527 // Check whether the next natural split point after the current one can
2528 // still fit the line, either because we can compress away whitespace,
2529 // or because the penalty the excess characters introduce is lower than
2530 // the break penalty.
2531 // We only do this for tokens that support reflowing, and thus allow us
2532 // to change the whitespace arbitrarily (e.g. comments).
2533 // Other tokens, like string literals, can be broken on arbitrary
2534 // positions.
2535
2536 // First, compute the columns from TailOffset to the next possible split
2537 // position.
2538 // For example:
2539 // ColumnLimit: |
2540 // // Some text that breaks
2541 // ^ tail offset
2542 // ^-- split
2543 // ^-------- to split columns
2544 // ^--- next split
2545 // ^--------------- to next split columns
2546 unsigned ToSplitColumns = Token->getRangeLength(
2547 LineIndex, TailOffset, Split.first, ContentStartColumn);
2548 LLVM_DEBUG(llvm::dbgs() << " ToSplit: " << ToSplitColumns << "\n");
2549
2550 BreakableToken::Split NextSplit = Token->getSplit(
2551 LineIndex, TailOffset + Split.first + Split.second, ColumnLimit,
2552 ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex);
2553 // Compute the columns necessary to fit the next non-breakable sequence
2554 // into the current line.
2555 unsigned ToNextSplitColumns = 0;
2556 if (NextSplit.first == StringRef::npos) {
2557 ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset,
2558 ContentStartColumn);
2559 } else {
2560 ToNextSplitColumns = Token->getRangeLength(
2561 LineIndex, TailOffset,
2562 Split.first + Split.second + NextSplit.first, ContentStartColumn);
2563 }
2564 // Compress the whitespace between the break and the start of the next
2565 // unbreakable sequence.
2566 ToNextSplitColumns =
2567 Token->getLengthAfterCompression(ToNextSplitColumns, Split);
2568 LLVM_DEBUG(llvm::dbgs()
2569 << " ContentStartColumn: " << ContentStartColumn << "\n");
2570 LLVM_DEBUG(llvm::dbgs()
2571 << " ToNextSplit: " << ToNextSplitColumns << "\n");
2572 // If the whitespace compression makes us fit, continue on the current
2573 // line.
2574 bool ContinueOnLine =
2575 ContentStartColumn + ToNextSplitColumns <= ColumnLimit;
2576 unsigned ExcessCharactersPenalty = 0;
2577 if (!ContinueOnLine && !Strict) {
2578 // Similarly, if the excess characters' penalty is lower than the
2579 // penalty of introducing a new break, continue on the current line.
2580 ExcessCharactersPenalty =
2581 (ContentStartColumn + ToNextSplitColumns - ColumnLimit) *
2582 Style.PenaltyExcessCharacter;
2583 LLVM_DEBUG(llvm::dbgs()
2584 << " Penalty excess: " << ExcessCharactersPenalty
2585 << "\n break : " << NewBreakPenalty << "\n");
2586 if (ExcessCharactersPenalty < NewBreakPenalty) {
2587 Exceeded = true;
2588 ContinueOnLine = true;
2589 }
2590 }
2591 if (ContinueOnLine) {
2592 LLVM_DEBUG(llvm::dbgs() << " Continuing on line...\n");
2593 // The current line fits after compressing the whitespace - reflow
2594 // the next line into it if possible.
2595 TryReflow = true;
2596 if (!DryRun) {
2597 Token->compressWhitespace(LineIndex, TailOffset, Split,
2598 Whitespaces);
2599 }
2600 // When we continue on the same line, leave one space between content.
2601 ContentStartColumn += ToSplitColumns + 1;
2602 Penalty += ExcessCharactersPenalty;
2603 TailOffset += Split.first + Split.second;
2604 RemainingTokenColumns = Token->getRemainingLength(
2605 LineIndex, TailOffset, ContentStartColumn);
2606 continue;
2607 }
2608 }
2609 LLVM_DEBUG(llvm::dbgs() << " Breaking...\n");
2610 // Update the ContentIndent only if the current line was not reflown with
2611 // the previous line, since in that case the previous line should still
2612 // determine the ContentIndent. Also never intent the last line.
2613 if (!Reflow)
2614 ContentIndent = Token->getContentIndent(LineIndex);
2615 LLVM_DEBUG(llvm::dbgs()
2616 << " ContentIndent: " << ContentIndent << "\n");
2617 ContentStartColumn = ContentIndent + Token->getContentStartColumn(
2618 LineIndex, /*Break=*/true);
2619
2620 unsigned NewRemainingTokenColumns = Token->getRemainingLength(
2621 LineIndex, TailOffset + Split.first + Split.second,
2622 ContentStartColumn);
2623 if (NewRemainingTokenColumns == 0) {
2624 // No content to indent.
2625 ContentIndent = 0;
2626 ContentStartColumn =
2627 Token->getContentStartColumn(LineIndex, /*Break=*/true);
2628 NewRemainingTokenColumns = Token->getRemainingLength(
2629 LineIndex, TailOffset + Split.first + Split.second,
2630 ContentStartColumn);
2631 }
2632
2633 // When breaking before a tab character, it may be moved by a few columns,
2634 // but will still be expanded to the next tab stop, so we don't save any
2635 // columns.
2636 if (NewRemainingTokenColumns >= RemainingTokenColumns) {
2637 // FIXME: Do we need to adjust the penalty?
2638 break;
2639 }
2640
2641 LLVM_DEBUG(llvm::dbgs() << " Breaking at: " << TailOffset + Split.first
2642 << ", " << Split.second << "\n");
2643 if (!DryRun) {
2644 Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent,
2645 Whitespaces);
2646 }
2647
2648 Penalty += NewBreakPenalty;
2649 TailOffset += Split.first + Split.second;
2650 RemainingTokenColumns = NewRemainingTokenColumns;
2651 BreakInserted = true;
2652 NewBreakBefore = true;
2653 }
2654 // In case there's another line, prepare the state for the start of the next
2655 // line.
2656 if (LineIndex + 1 != EndIndex) {
2657 unsigned NextLineIndex = LineIndex + 1;
2658 if (NewBreakBefore) {
2659 // After breaking a line, try to reflow the next line into the current
2660 // one once RemainingTokenColumns fits.
2661 TryReflow = true;
2662 }
2663 if (TryReflow) {
2664 // We decided that we want to try reflowing the next line into the
2665 // current one.
2666 // We will now adjust the state as if the reflow is successful (in
2667 // preparation for the next line), and see whether that works. If we
2668 // decide that we cannot reflow, we will later reset the state to the
2669 // start of the next line.
2670 Reflow = false;
2671 // As we did not continue breaking the line, RemainingTokenColumns is
2672 // known to fit after ContentStartColumn. Adapt ContentStartColumn to
2673 // the position at which we want to format the next line if we do
2674 // actually reflow.
2675 // When we reflow, we need to add a space between the end of the current
2676 // line and the next line's start column.
2677 ContentStartColumn += RemainingTokenColumns + 1;
2678 // Get the split that we need to reflow next logical line into the end
2679 // of the current one; the split will include any leading whitespace of
2680 // the next logical line.
2681 BreakableToken::Split SplitBeforeNext =
2682 Token->getReflowSplit(NextLineIndex, CommentPragmasRegex);
2683 LLVM_DEBUG(llvm::dbgs()
2684 << " Size of reflown text: " << ContentStartColumn
2685 << "\n Potential reflow split: ");
2686 if (SplitBeforeNext.first != StringRef::npos) {
2687 LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", "
2688 << SplitBeforeNext.second << "\n");
2689 TailOffset = SplitBeforeNext.first + SplitBeforeNext.second;
2690 // If the rest of the next line fits into the current line below the
2691 // column limit, we can safely reflow.
2692 RemainingTokenColumns = Token->getRemainingLength(
2693 NextLineIndex, TailOffset, ContentStartColumn);
2694 Reflow = true;
2695 if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) {
2696 LLVM_DEBUG(llvm::dbgs()
2697 << " Over limit after reflow, need: "
2698 << (ContentStartColumn + RemainingTokenColumns)
2699 << ", space: " << ColumnLimit
2700 << ", reflown prefix: " << ContentStartColumn
2701 << ", offset in line: " << TailOffset << "\n");
2702 // If the whole next line does not fit, try to find a point in
2703 // the next line at which we can break so that attaching the part
2704 // of the next line to that break point onto the current line is
2705 // below the column limit.
2706 BreakableToken::Split Split =
2707 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit,
2708 ContentStartColumn, CommentPragmasRegex);
2709 if (Split.first == StringRef::npos) {
2710 LLVM_DEBUG(llvm::dbgs() << " Did not find later break\n");
2711 Reflow = false;
2712 } else {
2713 // Check whether the first split point gets us below the column
2714 // limit. Note that we will execute this split below as part of
2715 // the normal token breaking and reflow logic within the line.
2716 unsigned ToSplitColumns = Token->getRangeLength(
2717 NextLineIndex, TailOffset, Split.first, ContentStartColumn);
2718 if (ContentStartColumn + ToSplitColumns > ColumnLimit) {
2719 LLVM_DEBUG(llvm::dbgs() << " Next split protrudes, need: "
2720 << (ContentStartColumn + ToSplitColumns)
2721 << ", space: " << ColumnLimit);
2722 unsigned ExcessCharactersPenalty =
2723 (ContentStartColumn + ToSplitColumns - ColumnLimit) *
2724 Style.PenaltyExcessCharacter;
2725 if (NewBreakPenalty < ExcessCharactersPenalty)
2726 Reflow = false;
2727 }
2728 }
2729 }
2730 } else {
2731 LLVM_DEBUG(llvm::dbgs() << "not found.\n");
2732 }
2733 }
2734 if (!Reflow) {
2735 // If we didn't reflow into the next line, the only space to consider is
2736 // the next logical line. Reset our state to match the start of the next
2737 // line.
2738 TailOffset = 0;
2739 ContentStartColumn =
2740 Token->getContentStartColumn(NextLineIndex, /*Break=*/false);
2741 RemainingTokenColumns = Token->getRemainingLength(
2742 NextLineIndex, TailOffset, ContentStartColumn);
2743 // Adapt the start of the token, for example indent.
2744 if (!DryRun)
2745 Token->adaptStartOfLine(NextLineIndex, Whitespaces);
2746 } else {
2747 // If we found a reflow split and have added a new break before the next
2748 // line, we are going to remove the line break at the start of the next
2749 // logical line. For example, here we'll add a new line break after
2750 // 'text', and subsequently delete the line break between 'that' and
2751 // 'reflows'.
2752 // // some text that
2753 // // reflows
2754 // ->
2755 // // some text
2756 // // that reflows
2757 // When adding the line break, we also added the penalty for it, so we
2758 // need to subtract that penalty again when we remove the line break due
2759 // to reflowing.
2760 if (NewBreakBefore) {
2761 assert(Penalty >= NewBreakPenalty);
2762 Penalty -= NewBreakPenalty;
2763 }
2764 if (!DryRun)
2765 Token->reflow(NextLineIndex, Whitespaces);
2766 }
2767 }
2768 }
2769
2770 BreakableToken::Split SplitAfterLastLine =
2771 Token->getSplitAfterLastLine(TailOffset);
2772 if (SplitAfterLastLine.first != StringRef::npos) {
2773 LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n");
2774
2775 // We add the last line's penalty here, since that line is going to be split
2776 // now.
2777 Penalty += Style.PenaltyExcessCharacter *
2778 (ContentStartColumn + RemainingTokenColumns - ColumnLimit);
2779
2780 if (!DryRun) {
2781 Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine,
2782 Whitespaces);
2783 }
2784 ContentStartColumn =
2785 Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true);
2786 RemainingTokenColumns = Token->getRemainingLength(
2787 Token->getLineCount() - 1,
2788 TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second,
2789 ContentStartColumn);
2790 }
2791
2792 State.Column = ContentStartColumn + RemainingTokenColumns -
2793 Current.UnbreakableTailLength;
2794
2795 if (BreakInserted) {
2796 if (!DryRun)
2797 Token->updateAfterBroken(Whitespaces);
2798
2799 // If we break the token inside a parameter list, we need to break before
2800 // the next parameter on all levels, so that the next parameter is clearly
2801 // visible. Line comments already introduce a break.
2802 if (Current.isNot(TT_LineComment))
2803 for (ParenState &Paren : State.Stack)
2804 Paren.BreakBeforeParameter = true;
2805
2806 if (Current.is(TT_BlockComment))
2807 State.NoContinuation = true;
2808
2809 State.Stack.back().LastSpace = StartColumn;
2810 }
2811
2812 Token->updateNextToken(State);
2813
2814 return {Penalty, Exceeded};
2815 }
2816
getColumnLimit(const LineState & State) const2817 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const {
2818 // In preprocessor directives reserve two chars for trailing " \".
2819 return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0);
2820 }
2821
nextIsMultilineString(const LineState & State)2822 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) {
2823 const FormatToken &Current = *State.NextToken;
2824 if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral))
2825 return false;
2826 // We never consider raw string literals "multiline" for the purpose of
2827 // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased
2828 // (see TokenAnnotator::mustBreakBefore().
2829 if (Current.TokenText.starts_with("R\""))
2830 return false;
2831 if (Current.IsMultiline)
2832 return true;
2833 if (Current.getNextNonComment() &&
2834 Current.getNextNonComment()->isStringLiteral()) {
2835 return true; // Implicit concatenation.
2836 }
2837 if (Style.ColumnLimit != 0 && Style.BreakStringLiterals &&
2838 State.Column + Current.ColumnWidth + Current.UnbreakableTailLength >
2839 Style.ColumnLimit) {
2840 return true; // String will be split.
2841 }
2842 return false;
2843 }
2844
2845 } // namespace format
2846 } // namespace clang
2847