1 //===--- ContinuationIndenter.cpp - Format C++ code -----------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 /// 9 /// \file 10 /// This file implements the continuation indenter. 11 /// 12 //===----------------------------------------------------------------------===// 13 14 #include "ContinuationIndenter.h" 15 #include "BreakableToken.h" 16 #include "FormatInternal.h" 17 #include "WhitespaceManager.h" 18 #include "clang/Basic/OperatorPrecedence.h" 19 #include "clang/Basic/SourceManager.h" 20 #include "clang/Format/Format.h" 21 #include "llvm/Support/Debug.h" 22 23 #define DEBUG_TYPE "format-indenter" 24 25 namespace clang { 26 namespace format { 27 28 // Returns true if a TT_SelectorName should be indented when wrapped, 29 // false otherwise. 30 static bool shouldIndentWrappedSelectorName(const FormatStyle &Style, 31 LineType LineType) { 32 return Style.IndentWrappedFunctionNames || LineType == LT_ObjCMethodDecl; 33 } 34 35 // Returns the length of everything up to the first possible line break after 36 // the ), ], } or > matching \c Tok. 37 static unsigned getLengthToMatchingParen(const FormatToken &Tok, 38 const std::vector<ParenState> &Stack) { 39 // Normally whether or not a break before T is possible is calculated and 40 // stored in T.CanBreakBefore. Braces, array initializers and text proto 41 // messages like `key: < ... >` are an exception: a break is possible 42 // before a closing brace R if a break was inserted after the corresponding 43 // opening brace. The information about whether or not a break is needed 44 // before a closing brace R is stored in the ParenState field 45 // S.BreakBeforeClosingBrace where S is the state that R closes. 46 // 47 // In order to decide whether there can be a break before encountered right 48 // braces, this implementation iterates over the sequence of tokens and over 49 // the paren stack in lockstep, keeping track of the stack level which visited 50 // right braces correspond to in MatchingStackIndex. 51 // 52 // For example, consider: 53 // L. <- line number 54 // 1. { 55 // 2. {1}, 56 // 3. {2}, 57 // 4. {{3}}} 58 // ^ where we call this method with this token. 59 // The paren stack at this point contains 3 brace levels: 60 // 0. { at line 1, BreakBeforeClosingBrace: true 61 // 1. first { at line 4, BreakBeforeClosingBrace: false 62 // 2. second { at line 4, BreakBeforeClosingBrace: false, 63 // where there might be fake parens levels in-between these levels. 64 // The algorithm will start at the first } on line 4, which is the matching 65 // brace of the initial left brace and at level 2 of the stack. Then, 66 // examining BreakBeforeClosingBrace: false at level 2, it will continue to 67 // the second } on line 4, and will traverse the stack downwards until it 68 // finds the matching { on level 1. Then, examining BreakBeforeClosingBrace: 69 // false at level 1, it will continue to the third } on line 4 and will 70 // traverse the stack downwards until it finds the matching { on level 0. 71 // Then, examining BreakBeforeClosingBrace: true at level 0, the algorithm 72 // will stop and will use the second } on line 4 to determine the length to 73 // return, as in this example the range will include the tokens: {3}} 74 // 75 // The algorithm will only traverse the stack if it encounters braces, array 76 // initializer squares or text proto angle brackets. 77 if (!Tok.MatchingParen) 78 return 0; 79 FormatToken *End = Tok.MatchingParen; 80 // Maintains a stack level corresponding to the current End token. 81 int MatchingStackIndex = Stack.size() - 1; 82 // Traverses the stack downwards, looking for the level to which LBrace 83 // corresponds. Returns either a pointer to the matching level or nullptr if 84 // LParen is not found in the initial portion of the stack up to 85 // MatchingStackIndex. 86 auto FindParenState = [&](const FormatToken *LBrace) -> const ParenState * { 87 while (MatchingStackIndex >= 0 && Stack[MatchingStackIndex].Tok != LBrace) 88 --MatchingStackIndex; 89 return MatchingStackIndex >= 0 ? &Stack[MatchingStackIndex] : nullptr; 90 }; 91 for (; End->Next; End = End->Next) { 92 if (End->Next->CanBreakBefore) 93 break; 94 if (!End->Next->closesScope()) 95 continue; 96 if (End->Next->MatchingParen && 97 End->Next->MatchingParen->isOneOf( 98 tok::l_brace, TT_ArrayInitializerLSquare, tok::less)) { 99 const ParenState *State = FindParenState(End->Next->MatchingParen); 100 if (State && State->BreakBeforeClosingBrace) 101 break; 102 } 103 } 104 return End->TotalLength - Tok.TotalLength + 1; 105 } 106 107 static unsigned getLengthToNextOperator(const FormatToken &Tok) { 108 if (!Tok.NextOperator) 109 return 0; 110 return Tok.NextOperator->TotalLength - Tok.TotalLength; 111 } 112 113 // Returns \c true if \c Tok is the "." or "->" of a call and starts the next 114 // segment of a builder type call. 115 static bool startsSegmentOfBuilderTypeCall(const FormatToken &Tok) { 116 return Tok.isMemberAccess() && Tok.Previous && Tok.Previous->closesScope(); 117 } 118 119 // Returns \c true if \c Current starts a new parameter. 120 static bool startsNextParameter(const FormatToken &Current, 121 const FormatStyle &Style) { 122 const FormatToken &Previous = *Current.Previous; 123 if (Current.is(TT_CtorInitializerComma) && 124 Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma) 125 return true; 126 if (Style.Language == FormatStyle::LK_Proto && Current.is(TT_SelectorName)) 127 return true; 128 return Previous.is(tok::comma) && !Current.isTrailingComment() && 129 ((Previous.isNot(TT_CtorInitializerComma) || 130 Style.BreakConstructorInitializers != 131 FormatStyle::BCIS_BeforeComma) && 132 (Previous.isNot(TT_InheritanceComma) || 133 Style.BreakInheritanceList != FormatStyle::BILS_BeforeComma)); 134 } 135 136 static bool opensProtoMessageField(const FormatToken &LessTok, 137 const FormatStyle &Style) { 138 if (LessTok.isNot(tok::less)) 139 return false; 140 return Style.Language == FormatStyle::LK_TextProto || 141 (Style.Language == FormatStyle::LK_Proto && 142 (LessTok.NestingLevel > 0 || 143 (LessTok.Previous && LessTok.Previous->is(tok::equal)))); 144 } 145 146 // Returns the delimiter of a raw string literal, or None if TokenText is not 147 // the text of a raw string literal. The delimiter could be the empty string. 148 // For example, the delimiter of R"deli(cont)deli" is deli. 149 static llvm::Optional<StringRef> getRawStringDelimiter(StringRef TokenText) { 150 if (TokenText.size() < 5 // The smallest raw string possible is 'R"()"'. 151 || !TokenText.startswith("R\"") || !TokenText.endswith("\"")) 152 return None; 153 154 // A raw string starts with 'R"<delimiter>(' and delimiter is ascii and has 155 // size at most 16 by the standard, so the first '(' must be among the first 156 // 19 bytes. 157 size_t LParenPos = TokenText.substr(0, 19).find_first_of('('); 158 if (LParenPos == StringRef::npos) 159 return None; 160 StringRef Delimiter = TokenText.substr(2, LParenPos - 2); 161 162 // Check that the string ends in ')Delimiter"'. 163 size_t RParenPos = TokenText.size() - Delimiter.size() - 2; 164 if (TokenText[RParenPos] != ')') 165 return None; 166 if (!TokenText.substr(RParenPos + 1).startswith(Delimiter)) 167 return None; 168 return Delimiter; 169 } 170 171 // Returns the canonical delimiter for \p Language, or the empty string if no 172 // canonical delimiter is specified. 173 static StringRef 174 getCanonicalRawStringDelimiter(const FormatStyle &Style, 175 FormatStyle::LanguageKind Language) { 176 for (const auto &Format : Style.RawStringFormats) { 177 if (Format.Language == Language) 178 return StringRef(Format.CanonicalDelimiter); 179 } 180 return ""; 181 } 182 183 RawStringFormatStyleManager::RawStringFormatStyleManager( 184 const FormatStyle &CodeStyle) { 185 for (const auto &RawStringFormat : CodeStyle.RawStringFormats) { 186 llvm::Optional<FormatStyle> LanguageStyle = 187 CodeStyle.GetLanguageStyle(RawStringFormat.Language); 188 if (!LanguageStyle) { 189 FormatStyle PredefinedStyle; 190 if (!getPredefinedStyle(RawStringFormat.BasedOnStyle, 191 RawStringFormat.Language, &PredefinedStyle)) { 192 PredefinedStyle = getLLVMStyle(); 193 PredefinedStyle.Language = RawStringFormat.Language; 194 } 195 LanguageStyle = PredefinedStyle; 196 } 197 LanguageStyle->ColumnLimit = CodeStyle.ColumnLimit; 198 for (StringRef Delimiter : RawStringFormat.Delimiters) { 199 DelimiterStyle.insert({Delimiter, *LanguageStyle}); 200 } 201 for (StringRef EnclosingFunction : RawStringFormat.EnclosingFunctions) { 202 EnclosingFunctionStyle.insert({EnclosingFunction, *LanguageStyle}); 203 } 204 } 205 } 206 207 llvm::Optional<FormatStyle> 208 RawStringFormatStyleManager::getDelimiterStyle(StringRef Delimiter) const { 209 auto It = DelimiterStyle.find(Delimiter); 210 if (It == DelimiterStyle.end()) 211 return None; 212 return It->second; 213 } 214 215 llvm::Optional<FormatStyle> 216 RawStringFormatStyleManager::getEnclosingFunctionStyle( 217 StringRef EnclosingFunction) const { 218 auto It = EnclosingFunctionStyle.find(EnclosingFunction); 219 if (It == EnclosingFunctionStyle.end()) 220 return None; 221 return It->second; 222 } 223 224 ContinuationIndenter::ContinuationIndenter(const FormatStyle &Style, 225 const AdditionalKeywords &Keywords, 226 const SourceManager &SourceMgr, 227 WhitespaceManager &Whitespaces, 228 encoding::Encoding Encoding, 229 bool BinPackInconclusiveFunctions) 230 : Style(Style), Keywords(Keywords), SourceMgr(SourceMgr), 231 Whitespaces(Whitespaces), Encoding(Encoding), 232 BinPackInconclusiveFunctions(BinPackInconclusiveFunctions), 233 CommentPragmasRegex(Style.CommentPragmas), RawStringFormats(Style) {} 234 235 LineState ContinuationIndenter::getInitialState(unsigned FirstIndent, 236 unsigned FirstStartColumn, 237 const AnnotatedLine *Line, 238 bool DryRun) { 239 LineState State; 240 State.FirstIndent = FirstIndent; 241 if (FirstStartColumn && Line->First->NewlinesBefore == 0) 242 State.Column = FirstStartColumn; 243 else 244 State.Column = FirstIndent; 245 // With preprocessor directive indentation, the line starts on column 0 246 // since it's indented after the hash, but FirstIndent is set to the 247 // preprocessor indent. 248 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash && 249 (Line->Type == LT_PreprocessorDirective || 250 Line->Type == LT_ImportStatement)) 251 State.Column = 0; 252 State.Line = Line; 253 State.NextToken = Line->First; 254 State.Stack.push_back(ParenState(/*Tok=*/nullptr, FirstIndent, FirstIndent, 255 /*AvoidBinPacking=*/false, 256 /*NoLineBreak=*/false)); 257 State.LineContainsContinuedForLoopSection = false; 258 State.NoContinuation = false; 259 State.StartOfStringLiteral = 0; 260 State.StartOfLineLevel = 0; 261 State.LowestLevelOnLine = 0; 262 State.IgnoreStackForComparison = false; 263 264 if (Style.Language == FormatStyle::LK_TextProto) { 265 // We need this in order to deal with the bin packing of text fields at 266 // global scope. 267 State.Stack.back().AvoidBinPacking = true; 268 State.Stack.back().BreakBeforeParameter = true; 269 State.Stack.back().AlignColons = false; 270 } 271 272 // The first token has already been indented and thus consumed. 273 moveStateToNextToken(State, DryRun, /*Newline=*/false); 274 return State; 275 } 276 277 bool ContinuationIndenter::canBreak(const LineState &State) { 278 const FormatToken &Current = *State.NextToken; 279 const FormatToken &Previous = *Current.Previous; 280 assert(&Previous == Current.Previous); 281 if (!Current.CanBreakBefore && !(State.Stack.back().BreakBeforeClosingBrace && 282 Current.closesBlockOrBlockTypeList(Style))) 283 return false; 284 // The opening "{" of a braced list has to be on the same line as the first 285 // element if it is nested in another braced init list or function call. 286 if (!Current.MustBreakBefore && Previous.is(tok::l_brace) && 287 Previous.isNot(TT_DictLiteral) && Previous.is(BK_BracedInit) && 288 Previous.Previous && 289 Previous.Previous->isOneOf(tok::l_brace, tok::l_paren, tok::comma)) 290 return false; 291 // This prevents breaks like: 292 // ... 293 // SomeParameter, OtherParameter).DoSomething( 294 // ... 295 // As they hide "DoSomething" and are generally bad for readability. 296 if (Previous.opensScope() && Previous.isNot(tok::l_brace) && 297 State.LowestLevelOnLine < State.StartOfLineLevel && 298 State.LowestLevelOnLine < Current.NestingLevel) 299 return false; 300 if (Current.isMemberAccess() && State.Stack.back().ContainsUnwrappedBuilder) 301 return false; 302 303 // Don't create a 'hanging' indent if there are multiple blocks in a single 304 // statement. 305 if (Previous.is(tok::l_brace) && State.Stack.size() > 1 && 306 State.Stack[State.Stack.size() - 2].NestedBlockInlined && 307 State.Stack[State.Stack.size() - 2].HasMultipleNestedBlocks) 308 return false; 309 310 // Don't break after very short return types (e.g. "void") as that is often 311 // unexpected. 312 if (Current.is(TT_FunctionDeclarationName) && State.Column < 6) { 313 if (Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_None) 314 return false; 315 } 316 317 // If binary operators are moved to the next line (including commas for some 318 // styles of constructor initializers), that's always ok. 319 if (!Current.isOneOf(TT_BinaryOperator, tok::comma) && 320 State.Stack.back().NoLineBreakInOperand) 321 return false; 322 323 if (Previous.is(tok::l_square) && Previous.is(TT_ObjCMethodExpr)) 324 return false; 325 326 return !State.Stack.back().NoLineBreak; 327 } 328 329 bool ContinuationIndenter::mustBreak(const LineState &State) { 330 const FormatToken &Current = *State.NextToken; 331 const FormatToken &Previous = *Current.Previous; 332 if (Style.BraceWrapping.BeforeLambdaBody && Current.CanBreakBefore && 333 Current.is(TT_LambdaLBrace) && Previous.isNot(TT_LineComment)) { 334 auto LambdaBodyLength = getLengthToMatchingParen(Current, State.Stack); 335 return (LambdaBodyLength > getColumnLimit(State)); 336 } 337 if (Current.MustBreakBefore || Current.is(TT_InlineASMColon)) 338 return true; 339 if (State.Stack.back().BreakBeforeClosingBrace && 340 Current.closesBlockOrBlockTypeList(Style)) 341 return true; 342 if (Previous.is(tok::semi) && State.LineContainsContinuedForLoopSection) 343 return true; 344 if (Style.Language == FormatStyle::LK_ObjC && 345 Style.ObjCBreakBeforeNestedBlockParam && 346 Current.ObjCSelectorNameParts > 1 && 347 Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)) { 348 return true; 349 } 350 // Avoid producing inconsistent states by requiring breaks where they are not 351 // permitted for C# generic type constraints. 352 if (State.Stack.back().IsCSharpGenericTypeConstraint && 353 Previous.isNot(TT_CSharpGenericTypeConstraintComma)) 354 return false; 355 if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) || 356 (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) && 357 Style.isCpp() && 358 // FIXME: This is a temporary workaround for the case where clang-format 359 // sets BreakBeforeParameter to avoid bin packing and this creates a 360 // completely unnecessary line break after a template type that isn't 361 // line-wrapped. 362 (Previous.NestingLevel == 1 || Style.BinPackParameters)) || 363 (Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) && 364 Previous.isNot(tok::question)) || 365 (!Style.BreakBeforeTernaryOperators && 366 Previous.is(TT_ConditionalExpr))) && 367 State.Stack.back().BreakBeforeParameter && !Current.isTrailingComment() && 368 !Current.isOneOf(tok::r_paren, tok::r_brace)) 369 return true; 370 if (State.Stack.back().IsChainedConditional && 371 ((Style.BreakBeforeTernaryOperators && Current.is(TT_ConditionalExpr) && 372 Current.is(tok::colon)) || 373 (!Style.BreakBeforeTernaryOperators && Previous.is(TT_ConditionalExpr) && 374 Previous.is(tok::colon)))) 375 return true; 376 if (((Previous.is(TT_DictLiteral) && Previous.is(tok::l_brace)) || 377 (Previous.is(TT_ArrayInitializerLSquare) && 378 Previous.ParameterCount > 1) || 379 opensProtoMessageField(Previous, Style)) && 380 Style.ColumnLimit > 0 && 381 getLengthToMatchingParen(Previous, State.Stack) + State.Column - 1 > 382 getColumnLimit(State)) 383 return true; 384 385 const FormatToken &BreakConstructorInitializersToken = 386 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon 387 ? Previous 388 : Current; 389 if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) && 390 (State.Column + State.Line->Last->TotalLength - Previous.TotalLength > 391 getColumnLimit(State) || 392 State.Stack.back().BreakBeforeParameter) && 393 (Style.AllowShortFunctionsOnASingleLine != FormatStyle::SFS_All || 394 Style.BreakConstructorInitializers != FormatStyle::BCIS_BeforeColon || 395 Style.ColumnLimit != 0)) 396 return true; 397 398 if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) && 399 State.Line->startsWith(TT_ObjCMethodSpecifier)) 400 return true; 401 if (Current.is(TT_SelectorName) && !Previous.is(tok::at) && 402 State.Stack.back().ObjCSelectorNameFound && 403 State.Stack.back().BreakBeforeParameter && 404 (Style.ObjCBreakBeforeNestedBlockParam || 405 !Current.startsSequence(TT_SelectorName, tok::colon, tok::caret))) 406 return true; 407 408 unsigned NewLineColumn = getNewLineColumn(State); 409 if (Current.isMemberAccess() && Style.ColumnLimit != 0 && 410 State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit && 411 (State.Column > NewLineColumn || 412 Current.NestingLevel < State.StartOfLineLevel)) 413 return true; 414 415 if (startsSegmentOfBuilderTypeCall(Current) && 416 (State.Stack.back().CallContinuation != 0 || 417 State.Stack.back().BreakBeforeParameter) && 418 // JavaScript is treated different here as there is a frequent pattern: 419 // SomeFunction(function() { 420 // ... 421 // }.bind(...)); 422 // FIXME: We should find a more generic solution to this problem. 423 !(State.Column <= NewLineColumn && 424 Style.Language == FormatStyle::LK_JavaScript) && 425 !(Previous.closesScopeAfterBlock() && State.Column <= NewLineColumn)) 426 return true; 427 428 // If the template declaration spans multiple lines, force wrap before the 429 // function/class declaration 430 if (Previous.ClosesTemplateDeclaration && 431 State.Stack.back().BreakBeforeParameter && Current.CanBreakBefore) 432 return true; 433 434 if (!State.Line->First->is(tok::kw_enum) && State.Column <= NewLineColumn) 435 return false; 436 437 if (Style.AlwaysBreakBeforeMultilineStrings && 438 (NewLineColumn == State.FirstIndent + Style.ContinuationIndentWidth || 439 Previous.is(tok::comma) || Current.NestingLevel < 2) && 440 !Previous.isOneOf(tok::kw_return, tok::lessless, tok::at, 441 Keywords.kw_dollar) && 442 !Previous.isOneOf(TT_InlineASMColon, TT_ConditionalExpr) && 443 nextIsMultilineString(State)) 444 return true; 445 446 // Using CanBreakBefore here and below takes care of the decision whether the 447 // current style uses wrapping before or after operators for the given 448 // operator. 449 if (Previous.is(TT_BinaryOperator) && Current.CanBreakBefore) { 450 // If we need to break somewhere inside the LHS of a binary expression, we 451 // should also break after the operator. Otherwise, the formatting would 452 // hide the operator precedence, e.g. in: 453 // if (aaaaaaaaaaaaaa == 454 // bbbbbbbbbbbbbb && c) {.. 455 // For comparisons, we only apply this rule, if the LHS is a binary 456 // expression itself as otherwise, the line breaks seem superfluous. 457 // We need special cases for ">>" which we have split into two ">" while 458 // lexing in order to make template parsing easier. 459 bool IsComparison = (Previous.getPrecedence() == prec::Relational || 460 Previous.getPrecedence() == prec::Equality || 461 Previous.getPrecedence() == prec::Spaceship) && 462 Previous.Previous && 463 Previous.Previous->isNot(TT_BinaryOperator); // For >>. 464 bool LHSIsBinaryExpr = 465 Previous.Previous && Previous.Previous->EndsBinaryExpression; 466 if ((!IsComparison || LHSIsBinaryExpr) && !Current.isTrailingComment() && 467 Previous.getPrecedence() != prec::Assignment && 468 State.Stack.back().BreakBeforeParameter) 469 return true; 470 } else if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore && 471 State.Stack.back().BreakBeforeParameter) { 472 return true; 473 } 474 475 // Same as above, but for the first "<<" operator. 476 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator) && 477 State.Stack.back().BreakBeforeParameter && 478 State.Stack.back().FirstLessLess == 0) 479 return true; 480 481 if (Current.NestingLevel == 0 && !Current.isTrailingComment()) { 482 // Always break after "template <...>" and leading annotations. This is only 483 // for cases where the entire line does not fit on a single line as a 484 // different LineFormatter would be used otherwise. 485 if (Previous.ClosesTemplateDeclaration) 486 return Style.AlwaysBreakTemplateDeclarations != FormatStyle::BTDS_No; 487 if (Previous.is(TT_FunctionAnnotationRParen)) 488 return true; 489 if (Previous.is(TT_LeadingJavaAnnotation) && Current.isNot(tok::l_paren) && 490 Current.isNot(TT_LeadingJavaAnnotation)) 491 return true; 492 } 493 494 // If the return type spans multiple lines, wrap before the function name. 495 if (((Current.is(TT_FunctionDeclarationName) && 496 // Don't break before a C# function when no break after return type 497 (!Style.isCSharp() || 498 Style.AlwaysBreakAfterReturnType != FormatStyle::RTBS_None)) || 499 (Current.is(tok::kw_operator) && !Previous.is(tok::coloncolon))) && 500 !Previous.is(tok::kw_template) && State.Stack.back().BreakBeforeParameter) 501 return true; 502 503 // The following could be precomputed as they do not depend on the state. 504 // However, as they should take effect only if the UnwrappedLine does not fit 505 // into the ColumnLimit, they are checked here in the ContinuationIndenter. 506 if (Style.ColumnLimit != 0 && Previous.is(BK_Block) && 507 Previous.is(tok::l_brace) && !Current.isOneOf(tok::r_brace, tok::comment)) 508 return true; 509 510 if (Current.is(tok::lessless) && 511 ((Previous.is(tok::identifier) && Previous.TokenText == "endl") || 512 (Previous.Tok.isLiteral() && (Previous.TokenText.endswith("\\n\"") || 513 Previous.TokenText == "\'\\n\'")))) 514 return true; 515 516 if (Previous.is(TT_BlockComment) && Previous.IsMultiline) 517 return true; 518 519 if (State.NoContinuation) 520 return true; 521 522 return false; 523 } 524 525 unsigned ContinuationIndenter::addTokenToState(LineState &State, bool Newline, 526 bool DryRun, 527 unsigned ExtraSpaces) { 528 const FormatToken &Current = *State.NextToken; 529 530 assert(!State.Stack.empty()); 531 State.NoContinuation = false; 532 533 if ((Current.is(TT_ImplicitStringLiteral) && 534 (Current.Previous->Tok.getIdentifierInfo() == nullptr || 535 Current.Previous->Tok.getIdentifierInfo()->getPPKeywordID() == 536 tok::pp_not_keyword))) { 537 unsigned EndColumn = 538 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getEnd()); 539 if (Current.LastNewlineOffset != 0) { 540 // If there is a newline within this token, the final column will solely 541 // determined by the current end column. 542 State.Column = EndColumn; 543 } else { 544 unsigned StartColumn = 545 SourceMgr.getSpellingColumnNumber(Current.WhitespaceRange.getBegin()); 546 assert(EndColumn >= StartColumn); 547 State.Column += EndColumn - StartColumn; 548 } 549 moveStateToNextToken(State, DryRun, /*Newline=*/false); 550 return 0; 551 } 552 553 unsigned Penalty = 0; 554 if (Newline) 555 Penalty = addTokenOnNewLine(State, DryRun); 556 else 557 addTokenOnCurrentLine(State, DryRun, ExtraSpaces); 558 559 return moveStateToNextToken(State, DryRun, Newline) + Penalty; 560 } 561 562 void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun, 563 unsigned ExtraSpaces) { 564 FormatToken &Current = *State.NextToken; 565 const FormatToken &Previous = *State.NextToken->Previous; 566 if (Current.is(tok::equal) && 567 (State.Line->First->is(tok::kw_for) || Current.NestingLevel == 0) && 568 State.Stack.back().VariablePos == 0) { 569 State.Stack.back().VariablePos = State.Column; 570 // Move over * and & if they are bound to the variable name. 571 const FormatToken *Tok = &Previous; 572 while (Tok && State.Stack.back().VariablePos >= Tok->ColumnWidth) { 573 State.Stack.back().VariablePos -= Tok->ColumnWidth; 574 if (Tok->SpacesRequiredBefore != 0) 575 break; 576 Tok = Tok->Previous; 577 } 578 if (Previous.PartOfMultiVariableDeclStmt) 579 State.Stack.back().LastSpace = State.Stack.back().VariablePos; 580 } 581 582 unsigned Spaces = Current.SpacesRequiredBefore + ExtraSpaces; 583 584 // Indent preprocessor directives after the hash if required. 585 int PPColumnCorrection = 0; 586 if (Style.IndentPPDirectives == FormatStyle::PPDIS_AfterHash && 587 Previous.is(tok::hash) && State.FirstIndent > 0 && 588 (State.Line->Type == LT_PreprocessorDirective || 589 State.Line->Type == LT_ImportStatement)) { 590 Spaces += State.FirstIndent; 591 592 // For preprocessor indent with tabs, State.Column will be 1 because of the 593 // hash. This causes second-level indents onward to have an extra space 594 // after the tabs. We avoid this misalignment by subtracting 1 from the 595 // column value passed to replaceWhitespace(). 596 if (Style.UseTab != FormatStyle::UT_Never) 597 PPColumnCorrection = -1; 598 } 599 600 if (!DryRun) 601 Whitespaces.replaceWhitespace(Current, /*Newlines=*/0, Spaces, 602 State.Column + Spaces + PPColumnCorrection); 603 604 // If "BreakBeforeInheritanceComma" mode, don't break within the inheritance 605 // declaration unless there is multiple inheritance. 606 if (Style.BreakInheritanceList == FormatStyle::BILS_BeforeComma && 607 Current.is(TT_InheritanceColon)) 608 State.Stack.back().NoLineBreak = true; 609 if (Style.BreakInheritanceList == FormatStyle::BILS_AfterColon && 610 Previous.is(TT_InheritanceColon)) 611 State.Stack.back().NoLineBreak = true; 612 613 if (Current.is(TT_SelectorName) && 614 !State.Stack.back().ObjCSelectorNameFound) { 615 unsigned MinIndent = 616 std::max(State.FirstIndent + Style.ContinuationIndentWidth, 617 State.Stack.back().Indent); 618 unsigned FirstColonPos = State.Column + Spaces + Current.ColumnWidth; 619 if (Current.LongestObjCSelectorName == 0) 620 State.Stack.back().AlignColons = false; 621 else if (MinIndent + Current.LongestObjCSelectorName > FirstColonPos) 622 State.Stack.back().ColonPos = MinIndent + Current.LongestObjCSelectorName; 623 else 624 State.Stack.back().ColonPos = FirstColonPos; 625 } 626 627 // In "AlwaysBreak" mode, enforce wrapping directly after the parenthesis by 628 // disallowing any further line breaks if there is no line break after the 629 // opening parenthesis. Don't break if it doesn't conserve columns. 630 if (Style.AlignAfterOpenBracket == FormatStyle::BAS_AlwaysBreak && 631 (Previous.isOneOf(tok::l_paren, TT_TemplateOpener, tok::l_square) || 632 (Previous.is(tok::l_brace) && Previous.isNot(BK_Block) && 633 Style.Cpp11BracedListStyle)) && 634 State.Column > getNewLineColumn(State) && 635 (!Previous.Previous || !Previous.Previous->isOneOf( 636 tok::kw_for, tok::kw_while, tok::kw_switch)) && 637 // Don't do this for simple (no expressions) one-argument function calls 638 // as that feels like needlessly wasting whitespace, e.g.: 639 // 640 // caaaaaaaaaaaall( 641 // caaaaaaaaaaaall( 642 // caaaaaaaaaaaall( 643 // caaaaaaaaaaaaaaaaaaaaaaall(aaaaaaaaaaaaaa, aaaaaaaaa)))); 644 Current.FakeLParens.size() > 0 && 645 Current.FakeLParens.back() > prec::Unknown) 646 State.Stack.back().NoLineBreak = true; 647 if (Previous.is(TT_TemplateString) && Previous.opensScope()) 648 State.Stack.back().NoLineBreak = true; 649 650 if (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign && 651 !State.Stack.back().IsCSharpGenericTypeConstraint && 652 Previous.opensScope() && Previous.isNot(TT_ObjCMethodExpr) && 653 (Current.isNot(TT_LineComment) || Previous.is(BK_BracedInit))) { 654 State.Stack.back().Indent = State.Column + Spaces; 655 State.Stack.back().IsAligned = true; 656 } 657 if (State.Stack.back().AvoidBinPacking && startsNextParameter(Current, Style)) 658 State.Stack.back().NoLineBreak = true; 659 if (startsSegmentOfBuilderTypeCall(Current) && 660 State.Column > getNewLineColumn(State)) 661 State.Stack.back().ContainsUnwrappedBuilder = true; 662 663 if (Current.is(TT_LambdaArrow) && Style.Language == FormatStyle::LK_Java) 664 State.Stack.back().NoLineBreak = true; 665 if (Current.isMemberAccess() && Previous.is(tok::r_paren) && 666 (Previous.MatchingParen && 667 (Previous.TotalLength - Previous.MatchingParen->TotalLength > 10))) 668 // If there is a function call with long parameters, break before trailing 669 // calls. This prevents things like: 670 // EXPECT_CALL(SomeLongParameter).Times( 671 // 2); 672 // We don't want to do this for short parameters as they can just be 673 // indexes. 674 State.Stack.back().NoLineBreak = true; 675 676 // Don't allow the RHS of an operator to be split over multiple lines unless 677 // there is a line-break right after the operator. 678 // Exclude relational operators, as there, it is always more desirable to 679 // have the LHS 'left' of the RHS. 680 const FormatToken *P = Current.getPreviousNonComment(); 681 if (!Current.is(tok::comment) && P && 682 (P->isOneOf(TT_BinaryOperator, tok::comma) || 683 (P->is(TT_ConditionalExpr) && P->is(tok::colon))) && 684 !P->isOneOf(TT_OverloadedOperator, TT_CtorInitializerComma) && 685 P->getPrecedence() != prec::Assignment && 686 P->getPrecedence() != prec::Relational && 687 P->getPrecedence() != prec::Spaceship) { 688 bool BreakBeforeOperator = 689 P->MustBreakBefore || P->is(tok::lessless) || 690 (P->is(TT_BinaryOperator) && 691 Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None) || 692 (P->is(TT_ConditionalExpr) && Style.BreakBeforeTernaryOperators); 693 // Don't do this if there are only two operands. In these cases, there is 694 // always a nice vertical separation between them and the extra line break 695 // does not help. 696 bool HasTwoOperands = 697 P->OperatorIndex == 0 && !P->NextOperator && !P->is(TT_ConditionalExpr); 698 if ((!BreakBeforeOperator && 699 !(HasTwoOperands && 700 Style.AlignOperands != FormatStyle::OAS_DontAlign)) || 701 (!State.Stack.back().LastOperatorWrapped && BreakBeforeOperator)) 702 State.Stack.back().NoLineBreakInOperand = true; 703 } 704 705 State.Column += Spaces; 706 if (Current.isNot(tok::comment) && Previous.is(tok::l_paren) && 707 Previous.Previous && 708 (Previous.Previous->is(tok::kw_for) || Previous.Previous->isIf())) { 709 // Treat the condition inside an if as if it was a second function 710 // parameter, i.e. let nested calls have a continuation indent. 711 State.Stack.back().LastSpace = State.Column; 712 State.Stack.back().NestedBlockIndent = State.Column; 713 } else if (!Current.isOneOf(tok::comment, tok::caret) && 714 ((Previous.is(tok::comma) && 715 !Previous.is(TT_OverloadedOperator)) || 716 (Previous.is(tok::colon) && Previous.is(TT_ObjCMethodExpr)))) { 717 State.Stack.back().LastSpace = State.Column; 718 } else if (Previous.is(TT_CtorInitializerColon) && 719 Style.BreakConstructorInitializers == 720 FormatStyle::BCIS_AfterColon) { 721 State.Stack.back().Indent = State.Column; 722 State.Stack.back().LastSpace = State.Column; 723 } else if ((Previous.isOneOf(TT_BinaryOperator, TT_ConditionalExpr, 724 TT_CtorInitializerColon)) && 725 ((Previous.getPrecedence() != prec::Assignment && 726 (Previous.isNot(tok::lessless) || Previous.OperatorIndex != 0 || 727 Previous.NextOperator)) || 728 Current.StartsBinaryExpression)) { 729 // Indent relative to the RHS of the expression unless this is a simple 730 // assignment without binary expression on the RHS. Also indent relative to 731 // unary operators and the colons of constructor initializers. 732 if (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None) 733 State.Stack.back().LastSpace = State.Column; 734 } else if (Previous.is(TT_InheritanceColon)) { 735 State.Stack.back().Indent = State.Column; 736 State.Stack.back().LastSpace = State.Column; 737 } else if (Current.is(TT_CSharpGenericTypeConstraintColon)) { 738 State.Stack.back().ColonPos = State.Column; 739 } else if (Previous.opensScope()) { 740 // If a function has a trailing call, indent all parameters from the 741 // opening parenthesis. This avoids confusing indents like: 742 // OuterFunction(InnerFunctionCall( // break 743 // ParameterToInnerFunction)) // break 744 // .SecondInnerFunctionCall(); 745 bool HasTrailingCall = false; 746 if (Previous.MatchingParen) { 747 const FormatToken *Next = Previous.MatchingParen->getNextNonComment(); 748 HasTrailingCall = Next && Next->isMemberAccess(); 749 } 750 if (HasTrailingCall && State.Stack.size() > 1 && 751 State.Stack[State.Stack.size() - 2].CallContinuation == 0) 752 State.Stack.back().LastSpace = State.Column; 753 } 754 } 755 756 unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State, 757 bool DryRun) { 758 FormatToken &Current = *State.NextToken; 759 const FormatToken &Previous = *State.NextToken->Previous; 760 761 // Extra penalty that needs to be added because of the way certain line 762 // breaks are chosen. 763 unsigned Penalty = 0; 764 765 const FormatToken *PreviousNonComment = Current.getPreviousNonComment(); 766 const FormatToken *NextNonComment = Previous.getNextNonComment(); 767 if (!NextNonComment) 768 NextNonComment = &Current; 769 // The first line break on any NestingLevel causes an extra penalty in order 770 // prefer similar line breaks. 771 if (!State.Stack.back().ContainsLineBreak) 772 Penalty += 15; 773 State.Stack.back().ContainsLineBreak = true; 774 775 Penalty += State.NextToken->SplitPenalty; 776 777 // Breaking before the first "<<" is generally not desirable if the LHS is 778 // short. Also always add the penalty if the LHS is split over multiple lines 779 // to avoid unnecessary line breaks that just work around this penalty. 780 if (NextNonComment->is(tok::lessless) && 781 State.Stack.back().FirstLessLess == 0 && 782 (State.Column <= Style.ColumnLimit / 3 || 783 State.Stack.back().BreakBeforeParameter)) 784 Penalty += Style.PenaltyBreakFirstLessLess; 785 786 State.Column = getNewLineColumn(State); 787 788 // Add Penalty proportional to amount of whitespace away from FirstColumn 789 // This tends to penalize several lines that are far-right indented, 790 // and prefers a line-break prior to such a block, e.g: 791 // 792 // Constructor() : 793 // member(value), looooooooooooooooong_member( 794 // looooooooooong_call(param_1, param_2, param_3)) 795 // would then become 796 // Constructor() : 797 // member(value), 798 // looooooooooooooooong_member( 799 // looooooooooong_call(param_1, param_2, param_3)) 800 if (State.Column > State.FirstIndent) 801 Penalty += 802 Style.PenaltyIndentedWhitespace * (State.Column - State.FirstIndent); 803 804 // Indent nested blocks relative to this column, unless in a very specific 805 // JavaScript special case where: 806 // 807 // var loooooong_name = 808 // function() { 809 // // code 810 // } 811 // 812 // is common and should be formatted like a free-standing function. The same 813 // goes for wrapping before the lambda return type arrow. 814 if (!Current.is(TT_LambdaArrow) && 815 (Style.Language != FormatStyle::LK_JavaScript || 816 Current.NestingLevel != 0 || !PreviousNonComment || 817 !PreviousNonComment->is(tok::equal) || 818 !Current.isOneOf(Keywords.kw_async, Keywords.kw_function))) 819 State.Stack.back().NestedBlockIndent = State.Column; 820 821 if (NextNonComment->isMemberAccess()) { 822 if (State.Stack.back().CallContinuation == 0) 823 State.Stack.back().CallContinuation = State.Column; 824 } else if (NextNonComment->is(TT_SelectorName)) { 825 if (!State.Stack.back().ObjCSelectorNameFound) { 826 if (NextNonComment->LongestObjCSelectorName == 0) { 827 State.Stack.back().AlignColons = false; 828 } else { 829 State.Stack.back().ColonPos = 830 (shouldIndentWrappedSelectorName(Style, State.Line->Type) 831 ? std::max(State.Stack.back().Indent, 832 State.FirstIndent + Style.ContinuationIndentWidth) 833 : State.Stack.back().Indent) + 834 std::max(NextNonComment->LongestObjCSelectorName, 835 NextNonComment->ColumnWidth); 836 } 837 } else if (State.Stack.back().AlignColons && 838 State.Stack.back().ColonPos <= NextNonComment->ColumnWidth) { 839 State.Stack.back().ColonPos = State.Column + NextNonComment->ColumnWidth; 840 } 841 } else if (PreviousNonComment && PreviousNonComment->is(tok::colon) && 842 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) { 843 // FIXME: This is hacky, find a better way. The problem is that in an ObjC 844 // method expression, the block should be aligned to the line starting it, 845 // e.g.: 846 // [aaaaaaaaaaaaaaa aaaaaaaaa: \\ break for some reason 847 // ^(int *i) { 848 // // ... 849 // }]; 850 // Thus, we set LastSpace of the next higher NestingLevel, to which we move 851 // when we consume all of the "}"'s FakeRParens at the "{". 852 if (State.Stack.size() > 1) 853 State.Stack[State.Stack.size() - 2].LastSpace = 854 std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) + 855 Style.ContinuationIndentWidth; 856 } 857 858 if ((PreviousNonComment && 859 PreviousNonComment->isOneOf(tok::comma, tok::semi) && 860 !State.Stack.back().AvoidBinPacking) || 861 Previous.is(TT_BinaryOperator)) 862 State.Stack.back().BreakBeforeParameter = false; 863 if (PreviousNonComment && 864 PreviousNonComment->isOneOf(TT_TemplateCloser, TT_JavaAnnotation) && 865 Current.NestingLevel == 0) 866 State.Stack.back().BreakBeforeParameter = false; 867 if (NextNonComment->is(tok::question) || 868 (PreviousNonComment && PreviousNonComment->is(tok::question))) 869 State.Stack.back().BreakBeforeParameter = true; 870 if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore) 871 State.Stack.back().BreakBeforeParameter = false; 872 873 if (!DryRun) { 874 unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1; 875 if (Current.is(tok::r_brace) && Current.MatchingParen && 876 // Only strip trailing empty lines for l_braces that have children, i.e. 877 // for function expressions (lambdas, arrows, etc). 878 !Current.MatchingParen->Children.empty()) { 879 // lambdas and arrow functions are expressions, thus their r_brace is not 880 // on its own line, and thus not covered by UnwrappedLineFormatter's logic 881 // about removing empty lines on closing blocks. Special case them here. 882 MaxEmptyLinesToKeep = 1; 883 } 884 unsigned Newlines = 885 std::max(1u, std::min(Current.NewlinesBefore, MaxEmptyLinesToKeep)); 886 bool ContinuePPDirective = 887 State.Line->InPPDirective && State.Line->Type != LT_ImportStatement; 888 Whitespaces.replaceWhitespace(Current, Newlines, State.Column, State.Column, 889 State.Stack.back().IsAligned, 890 ContinuePPDirective); 891 } 892 893 if (!Current.isTrailingComment()) 894 State.Stack.back().LastSpace = State.Column; 895 if (Current.is(tok::lessless)) 896 // If we are breaking before a "<<", we always want to indent relative to 897 // RHS. This is necessary only for "<<", as we special-case it and don't 898 // always indent relative to the RHS. 899 State.Stack.back().LastSpace += 3; // 3 -> width of "<< ". 900 901 State.StartOfLineLevel = Current.NestingLevel; 902 State.LowestLevelOnLine = Current.NestingLevel; 903 904 // Any break on this level means that the parent level has been broken 905 // and we need to avoid bin packing there. 906 bool NestedBlockSpecialCase = 907 (!Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 && 908 State.Stack[State.Stack.size() - 2].NestedBlockInlined) || 909 (Style.Language == FormatStyle::LK_ObjC && Current.is(tok::r_brace) && 910 State.Stack.size() > 1 && !Style.ObjCBreakBeforeNestedBlockParam); 911 if (!NestedBlockSpecialCase) 912 for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i) 913 State.Stack[i].BreakBeforeParameter = true; 914 915 if (PreviousNonComment && 916 !PreviousNonComment->isOneOf(tok::comma, tok::colon, tok::semi) && 917 (PreviousNonComment->isNot(TT_TemplateCloser) || 918 Current.NestingLevel != 0) && 919 !PreviousNonComment->isOneOf( 920 TT_BinaryOperator, TT_FunctionAnnotationRParen, TT_JavaAnnotation, 921 TT_LeadingJavaAnnotation) && 922 Current.isNot(TT_BinaryOperator) && !PreviousNonComment->opensScope()) 923 State.Stack.back().BreakBeforeParameter = true; 924 925 // If we break after { or the [ of an array initializer, we should also break 926 // before the corresponding } or ]. 927 if (PreviousNonComment && 928 (PreviousNonComment->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) || 929 opensProtoMessageField(*PreviousNonComment, Style))) 930 State.Stack.back().BreakBeforeClosingBrace = true; 931 932 if (State.Stack.back().AvoidBinPacking) { 933 // If we are breaking after '(', '{', '<', or this is the break after a ':' 934 // to start a member initializater list in a constructor, this should not 935 // be considered bin packing unless the relevant AllowAll option is false or 936 // this is a dict/object literal. 937 bool PreviousIsBreakingCtorInitializerColon = 938 Previous.is(TT_CtorInitializerColon) && 939 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon; 940 if (!(Previous.isOneOf(tok::l_paren, tok::l_brace, TT_BinaryOperator) || 941 PreviousIsBreakingCtorInitializerColon) || 942 (!Style.AllowAllParametersOfDeclarationOnNextLine && 943 State.Line->MustBeDeclaration) || 944 (!Style.AllowAllArgumentsOnNextLine && 945 !State.Line->MustBeDeclaration) || 946 (!Style.AllowAllConstructorInitializersOnNextLine && 947 PreviousIsBreakingCtorInitializerColon) || 948 Previous.is(TT_DictLiteral)) 949 State.Stack.back().BreakBeforeParameter = true; 950 951 // If we are breaking after a ':' to start a member initializer list, 952 // and we allow all arguments on the next line, we should not break 953 // before the next parameter. 954 if (PreviousIsBreakingCtorInitializerColon && 955 Style.AllowAllConstructorInitializersOnNextLine) 956 State.Stack.back().BreakBeforeParameter = false; 957 } 958 959 return Penalty; 960 } 961 962 unsigned ContinuationIndenter::getNewLineColumn(const LineState &State) { 963 if (!State.NextToken || !State.NextToken->Previous) 964 return 0; 965 966 FormatToken &Current = *State.NextToken; 967 968 if (State.Stack.back().IsCSharpGenericTypeConstraint && 969 Current.isNot(TT_CSharpGenericTypeConstraint)) 970 return State.Stack.back().ColonPos + 2; 971 972 const FormatToken &Previous = *Current.Previous; 973 // If we are continuing an expression, we want to use the continuation indent. 974 unsigned ContinuationIndent = 975 std::max(State.Stack.back().LastSpace, State.Stack.back().Indent) + 976 Style.ContinuationIndentWidth; 977 const FormatToken *PreviousNonComment = Current.getPreviousNonComment(); 978 const FormatToken *NextNonComment = Previous.getNextNonComment(); 979 if (!NextNonComment) 980 NextNonComment = &Current; 981 982 // Java specific bits. 983 if (Style.Language == FormatStyle::LK_Java && 984 Current.isOneOf(Keywords.kw_implements, Keywords.kw_extends)) 985 return std::max(State.Stack.back().LastSpace, 986 State.Stack.back().Indent + Style.ContinuationIndentWidth); 987 988 if (Style.BreakBeforeBraces == FormatStyle::BS_Whitesmiths && 989 State.Line->First->is(tok::kw_enum)) 990 return (Style.IndentWidth * State.Line->First->IndentLevel) + 991 Style.IndentWidth; 992 993 if (NextNonComment->is(tok::l_brace) && NextNonComment->is(BK_Block)) 994 return Current.NestingLevel == 0 ? State.FirstIndent 995 : State.Stack.back().Indent; 996 if ((Current.isOneOf(tok::r_brace, tok::r_square) || 997 (Current.is(tok::greater) && 998 (Style.Language == FormatStyle::LK_Proto || 999 Style.Language == FormatStyle::LK_TextProto))) && 1000 State.Stack.size() > 1) { 1001 if (Current.closesBlockOrBlockTypeList(Style)) 1002 return State.Stack[State.Stack.size() - 2].NestedBlockIndent; 1003 if (Current.MatchingParen && Current.MatchingParen->is(BK_BracedInit)) 1004 return State.Stack[State.Stack.size() - 2].LastSpace; 1005 return State.FirstIndent; 1006 } 1007 // Indent a closing parenthesis at the previous level if followed by a semi, 1008 // const, or opening brace. This allows indentations such as: 1009 // foo( 1010 // a, 1011 // ); 1012 // int Foo::getter( 1013 // // 1014 // ) const { 1015 // return foo; 1016 // } 1017 // function foo( 1018 // a, 1019 // ) { 1020 // code(); // 1021 // } 1022 if (Current.is(tok::r_paren) && State.Stack.size() > 1 && 1023 (!Current.Next || 1024 Current.Next->isOneOf(tok::semi, tok::kw_const, tok::l_brace))) 1025 return State.Stack[State.Stack.size() - 2].LastSpace; 1026 if (NextNonComment->is(TT_TemplateString) && NextNonComment->closesScope()) 1027 return State.Stack[State.Stack.size() - 2].LastSpace; 1028 if (Current.is(tok::identifier) && Current.Next && 1029 (Current.Next->is(TT_DictLiteral) || 1030 ((Style.Language == FormatStyle::LK_Proto || 1031 Style.Language == FormatStyle::LK_TextProto) && 1032 Current.Next->isOneOf(tok::less, tok::l_brace)))) 1033 return State.Stack.back().Indent; 1034 if (NextNonComment->is(TT_ObjCStringLiteral) && 1035 State.StartOfStringLiteral != 0) 1036 return State.StartOfStringLiteral - 1; 1037 if (NextNonComment->isStringLiteral() && State.StartOfStringLiteral != 0) 1038 return State.StartOfStringLiteral; 1039 if (NextNonComment->is(tok::lessless) && 1040 State.Stack.back().FirstLessLess != 0) 1041 return State.Stack.back().FirstLessLess; 1042 if (NextNonComment->isMemberAccess()) { 1043 if (State.Stack.back().CallContinuation == 0) 1044 return ContinuationIndent; 1045 return State.Stack.back().CallContinuation; 1046 } 1047 if (State.Stack.back().QuestionColumn != 0 && 1048 ((NextNonComment->is(tok::colon) && 1049 NextNonComment->is(TT_ConditionalExpr)) || 1050 Previous.is(TT_ConditionalExpr))) { 1051 if (((NextNonComment->is(tok::colon) && NextNonComment->Next && 1052 !NextNonComment->Next->FakeLParens.empty() && 1053 NextNonComment->Next->FakeLParens.back() == prec::Conditional) || 1054 (Previous.is(tok::colon) && !Current.FakeLParens.empty() && 1055 Current.FakeLParens.back() == prec::Conditional)) && 1056 !State.Stack.back().IsWrappedConditional) { 1057 // NOTE: we may tweak this slightly: 1058 // * not remove the 'lead' ContinuationIndentWidth 1059 // * always un-indent by the operator when 1060 // BreakBeforeTernaryOperators=true 1061 unsigned Indent = State.Stack.back().Indent; 1062 if (Style.AlignOperands != FormatStyle::OAS_DontAlign) { 1063 Indent -= Style.ContinuationIndentWidth; 1064 } 1065 if (Style.BreakBeforeTernaryOperators && 1066 State.Stack.back().UnindentOperator) 1067 Indent -= 2; 1068 return Indent; 1069 } 1070 return State.Stack.back().QuestionColumn; 1071 } 1072 if (Previous.is(tok::comma) && State.Stack.back().VariablePos != 0) 1073 return State.Stack.back().VariablePos; 1074 if ((PreviousNonComment && 1075 (PreviousNonComment->ClosesTemplateDeclaration || 1076 PreviousNonComment->isOneOf( 1077 TT_AttributeParen, TT_AttributeSquare, TT_FunctionAnnotationRParen, 1078 TT_JavaAnnotation, TT_LeadingJavaAnnotation))) || 1079 (!Style.IndentWrappedFunctionNames && 1080 NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName))) 1081 return std::max(State.Stack.back().LastSpace, State.Stack.back().Indent); 1082 if (NextNonComment->is(TT_SelectorName)) { 1083 if (!State.Stack.back().ObjCSelectorNameFound) { 1084 unsigned MinIndent = State.Stack.back().Indent; 1085 if (shouldIndentWrappedSelectorName(Style, State.Line->Type)) 1086 MinIndent = std::max(MinIndent, 1087 State.FirstIndent + Style.ContinuationIndentWidth); 1088 // If LongestObjCSelectorName is 0, we are indenting the first 1089 // part of an ObjC selector (or a selector component which is 1090 // not colon-aligned due to block formatting). 1091 // 1092 // Otherwise, we are indenting a subsequent part of an ObjC 1093 // selector which should be colon-aligned to the longest 1094 // component of the ObjC selector. 1095 // 1096 // In either case, we want to respect Style.IndentWrappedFunctionNames. 1097 return MinIndent + 1098 std::max(NextNonComment->LongestObjCSelectorName, 1099 NextNonComment->ColumnWidth) - 1100 NextNonComment->ColumnWidth; 1101 } 1102 if (!State.Stack.back().AlignColons) 1103 return State.Stack.back().Indent; 1104 if (State.Stack.back().ColonPos > NextNonComment->ColumnWidth) 1105 return State.Stack.back().ColonPos - NextNonComment->ColumnWidth; 1106 return State.Stack.back().Indent; 1107 } 1108 if (NextNonComment->is(tok::colon) && NextNonComment->is(TT_ObjCMethodExpr)) 1109 return State.Stack.back().ColonPos; 1110 if (NextNonComment->is(TT_ArraySubscriptLSquare)) { 1111 if (State.Stack.back().StartOfArraySubscripts != 0) 1112 return State.Stack.back().StartOfArraySubscripts; 1113 else if (Style.isCSharp()) // C# allows `["key"] = value` inside object 1114 // initializers. 1115 return State.Stack.back().Indent; 1116 return ContinuationIndent; 1117 } 1118 1119 // This ensure that we correctly format ObjC methods calls without inputs, 1120 // i.e. where the last element isn't selector like: [callee method]; 1121 if (NextNonComment->is(tok::identifier) && NextNonComment->FakeRParens == 0 && 1122 NextNonComment->Next && NextNonComment->Next->is(TT_ObjCMethodExpr)) 1123 return State.Stack.back().Indent; 1124 1125 if (NextNonComment->isOneOf(TT_StartOfName, TT_PointerOrReference) || 1126 Previous.isOneOf(tok::coloncolon, tok::equal, TT_JsTypeColon)) 1127 return ContinuationIndent; 1128 if (PreviousNonComment && PreviousNonComment->is(tok::colon) && 1129 PreviousNonComment->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral)) 1130 return ContinuationIndent; 1131 if (NextNonComment->is(TT_CtorInitializerComma)) 1132 return State.Stack.back().Indent; 1133 if (PreviousNonComment && PreviousNonComment->is(TT_CtorInitializerColon) && 1134 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) 1135 return State.Stack.back().Indent; 1136 if (PreviousNonComment && PreviousNonComment->is(TT_InheritanceColon) && 1137 Style.BreakInheritanceList == FormatStyle::BILS_AfterColon) 1138 return State.Stack.back().Indent; 1139 if (NextNonComment->isOneOf(TT_CtorInitializerColon, TT_InheritanceColon, 1140 TT_InheritanceComma)) 1141 return State.FirstIndent + Style.ConstructorInitializerIndentWidth; 1142 if (Previous.is(tok::r_paren) && !Current.isBinaryOperator() && 1143 !Current.isOneOf(tok::colon, tok::comment)) 1144 return ContinuationIndent; 1145 if (Current.is(TT_ProtoExtensionLSquare)) 1146 return State.Stack.back().Indent; 1147 if (Current.isBinaryOperator() && State.Stack.back().UnindentOperator) 1148 return State.Stack.back().Indent - Current.Tok.getLength() - 1149 Current.SpacesRequiredBefore; 1150 if (Current.isOneOf(tok::comment, TT_BlockComment, TT_LineComment) && 1151 NextNonComment->isBinaryOperator() && State.Stack.back().UnindentOperator) 1152 return State.Stack.back().Indent - NextNonComment->Tok.getLength() - 1153 NextNonComment->SpacesRequiredBefore; 1154 if (State.Stack.back().Indent == State.FirstIndent && PreviousNonComment && 1155 !PreviousNonComment->isOneOf(tok::r_brace, TT_CtorInitializerComma)) 1156 // Ensure that we fall back to the continuation indent width instead of 1157 // just flushing continuations left. 1158 return State.Stack.back().Indent + Style.ContinuationIndentWidth; 1159 return State.Stack.back().Indent; 1160 } 1161 1162 static bool hasNestedBlockInlined(const FormatToken *Previous, 1163 const FormatToken &Current, 1164 const FormatStyle &Style) { 1165 if (Previous->isNot(tok::l_paren)) 1166 return true; 1167 if (Previous->ParameterCount > 1) 1168 return true; 1169 1170 // Also a nested block if contains a lambda inside function with 1 parameter 1171 return (Style.BraceWrapping.BeforeLambdaBody && Current.is(TT_LambdaLSquare)); 1172 } 1173 1174 unsigned ContinuationIndenter::moveStateToNextToken(LineState &State, 1175 bool DryRun, bool Newline) { 1176 assert(State.Stack.size()); 1177 const FormatToken &Current = *State.NextToken; 1178 1179 if (Current.is(TT_CSharpGenericTypeConstraint)) 1180 State.Stack.back().IsCSharpGenericTypeConstraint = true; 1181 if (Current.isOneOf(tok::comma, TT_BinaryOperator)) 1182 State.Stack.back().NoLineBreakInOperand = false; 1183 if (Current.isOneOf(TT_InheritanceColon, TT_CSharpGenericTypeConstraintColon)) 1184 State.Stack.back().AvoidBinPacking = true; 1185 if (Current.is(tok::lessless) && Current.isNot(TT_OverloadedOperator)) { 1186 if (State.Stack.back().FirstLessLess == 0) 1187 State.Stack.back().FirstLessLess = State.Column; 1188 else 1189 State.Stack.back().LastOperatorWrapped = Newline; 1190 } 1191 if (Current.is(TT_BinaryOperator) && Current.isNot(tok::lessless)) 1192 State.Stack.back().LastOperatorWrapped = Newline; 1193 if (Current.is(TT_ConditionalExpr) && Current.Previous && 1194 !Current.Previous->is(TT_ConditionalExpr)) 1195 State.Stack.back().LastOperatorWrapped = Newline; 1196 if (Current.is(TT_ArraySubscriptLSquare) && 1197 State.Stack.back().StartOfArraySubscripts == 0) 1198 State.Stack.back().StartOfArraySubscripts = State.Column; 1199 if (Current.is(TT_ConditionalExpr) && Current.is(tok::question) && 1200 ((Current.MustBreakBefore) || 1201 (Current.getNextNonComment() && 1202 Current.getNextNonComment()->MustBreakBefore))) 1203 State.Stack.back().IsWrappedConditional = true; 1204 if (Style.BreakBeforeTernaryOperators && Current.is(tok::question)) 1205 State.Stack.back().QuestionColumn = State.Column; 1206 if (!Style.BreakBeforeTernaryOperators && Current.isNot(tok::colon)) { 1207 const FormatToken *Previous = Current.Previous; 1208 while (Previous && Previous->isTrailingComment()) 1209 Previous = Previous->Previous; 1210 if (Previous && Previous->is(tok::question)) 1211 State.Stack.back().QuestionColumn = State.Column; 1212 } 1213 if (!Current.opensScope() && !Current.closesScope() && 1214 !Current.is(TT_PointerOrReference)) 1215 State.LowestLevelOnLine = 1216 std::min(State.LowestLevelOnLine, Current.NestingLevel); 1217 if (Current.isMemberAccess()) 1218 State.Stack.back().StartOfFunctionCall = 1219 !Current.NextOperator ? 0 : State.Column; 1220 if (Current.is(TT_SelectorName)) 1221 State.Stack.back().ObjCSelectorNameFound = true; 1222 if (Current.is(TT_CtorInitializerColon) && 1223 Style.BreakConstructorInitializers != FormatStyle::BCIS_AfterColon) { 1224 // Indent 2 from the column, so: 1225 // SomeClass::SomeClass() 1226 // : First(...), ... 1227 // Next(...) 1228 // ^ line up here. 1229 State.Stack.back().Indent = 1230 State.Column + 1231 (Style.BreakConstructorInitializers == FormatStyle::BCIS_BeforeComma 1232 ? 0 1233 : 2); 1234 State.Stack.back().NestedBlockIndent = State.Stack.back().Indent; 1235 if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) { 1236 State.Stack.back().AvoidBinPacking = true; 1237 State.Stack.back().BreakBeforeParameter = 1238 !Style.AllowAllConstructorInitializersOnNextLine; 1239 } else { 1240 State.Stack.back().BreakBeforeParameter = false; 1241 } 1242 } 1243 if (Current.is(TT_CtorInitializerColon) && 1244 Style.BreakConstructorInitializers == FormatStyle::BCIS_AfterColon) { 1245 State.Stack.back().Indent = 1246 State.FirstIndent + Style.ConstructorInitializerIndentWidth; 1247 State.Stack.back().NestedBlockIndent = State.Stack.back().Indent; 1248 if (Style.ConstructorInitializerAllOnOneLineOrOnePerLine) 1249 State.Stack.back().AvoidBinPacking = true; 1250 } 1251 if (Current.is(TT_InheritanceColon)) 1252 State.Stack.back().Indent = 1253 State.FirstIndent + Style.ConstructorInitializerIndentWidth; 1254 if (Current.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) && Newline) 1255 State.Stack.back().NestedBlockIndent = 1256 State.Column + Current.ColumnWidth + 1; 1257 if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow)) 1258 State.Stack.back().LastSpace = State.Column; 1259 1260 // Insert scopes created by fake parenthesis. 1261 const FormatToken *Previous = Current.getPreviousNonComment(); 1262 1263 // Add special behavior to support a format commonly used for JavaScript 1264 // closures: 1265 // SomeFunction(function() { 1266 // foo(); 1267 // bar(); 1268 // }, a, b, c); 1269 if (Current.isNot(tok::comment) && Previous && 1270 Previous->isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) && 1271 !Previous->is(TT_DictLiteral) && State.Stack.size() > 1 && 1272 !State.Stack.back().HasMultipleNestedBlocks) { 1273 if (State.Stack[State.Stack.size() - 2].NestedBlockInlined && Newline) 1274 for (unsigned i = 0, e = State.Stack.size() - 1; i != e; ++i) 1275 State.Stack[i].NoLineBreak = true; 1276 State.Stack[State.Stack.size() - 2].NestedBlockInlined = false; 1277 } 1278 if (Previous && 1279 (Previous->isOneOf(tok::l_paren, tok::comma, tok::colon) || 1280 Previous->isOneOf(TT_BinaryOperator, TT_ConditionalExpr)) && 1281 !Previous->isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)) { 1282 State.Stack.back().NestedBlockInlined = 1283 !Newline && hasNestedBlockInlined(Previous, Current, Style); 1284 } 1285 1286 moveStatePastFakeLParens(State, Newline); 1287 moveStatePastScopeCloser(State); 1288 bool AllowBreak = !State.Stack.back().NoLineBreak && 1289 !State.Stack.back().NoLineBreakInOperand; 1290 moveStatePastScopeOpener(State, Newline); 1291 moveStatePastFakeRParens(State); 1292 1293 if (Current.is(TT_ObjCStringLiteral) && State.StartOfStringLiteral == 0) 1294 State.StartOfStringLiteral = State.Column + 1; 1295 if (Current.is(TT_CSharpStringLiteral) && State.StartOfStringLiteral == 0) 1296 State.StartOfStringLiteral = State.Column + 1; 1297 else if (Current.isStringLiteral() && State.StartOfStringLiteral == 0) 1298 State.StartOfStringLiteral = State.Column; 1299 else if (!Current.isOneOf(tok::comment, tok::identifier, tok::hash) && 1300 !Current.isStringLiteral()) 1301 State.StartOfStringLiteral = 0; 1302 1303 State.Column += Current.ColumnWidth; 1304 State.NextToken = State.NextToken->Next; 1305 1306 unsigned Penalty = 1307 handleEndOfLine(Current, State, DryRun, AllowBreak, Newline); 1308 1309 if (Current.Role) 1310 Current.Role->formatFromToken(State, this, DryRun); 1311 // If the previous has a special role, let it consume tokens as appropriate. 1312 // It is necessary to start at the previous token for the only implemented 1313 // role (comma separated list). That way, the decision whether or not to break 1314 // after the "{" is already done and both options are tried and evaluated. 1315 // FIXME: This is ugly, find a better way. 1316 if (Previous && Previous->Role) 1317 Penalty += Previous->Role->formatAfterToken(State, this, DryRun); 1318 1319 return Penalty; 1320 } 1321 1322 void ContinuationIndenter::moveStatePastFakeLParens(LineState &State, 1323 bool Newline) { 1324 const FormatToken &Current = *State.NextToken; 1325 const FormatToken *Previous = Current.getPreviousNonComment(); 1326 1327 // Don't add extra indentation for the first fake parenthesis after 1328 // 'return', assignments or opening <({[. The indentation for these cases 1329 // is special cased. 1330 bool SkipFirstExtraIndent = 1331 (Previous && (Previous->opensScope() || 1332 Previous->isOneOf(tok::semi, tok::kw_return) || 1333 (Previous->getPrecedence() == prec::Assignment && 1334 Style.AlignOperands != FormatStyle::OAS_DontAlign) || 1335 Previous->is(TT_ObjCMethodExpr))); 1336 for (SmallVectorImpl<prec::Level>::const_reverse_iterator 1337 I = Current.FakeLParens.rbegin(), 1338 E = Current.FakeLParens.rend(); 1339 I != E; ++I) { 1340 ParenState NewParenState = State.Stack.back(); 1341 NewParenState.Tok = nullptr; 1342 NewParenState.ContainsLineBreak = false; 1343 NewParenState.LastOperatorWrapped = true; 1344 NewParenState.IsChainedConditional = false; 1345 NewParenState.IsWrappedConditional = false; 1346 NewParenState.UnindentOperator = false; 1347 NewParenState.NoLineBreak = 1348 NewParenState.NoLineBreak || State.Stack.back().NoLineBreakInOperand; 1349 1350 // Don't propagate AvoidBinPacking into subexpressions of arg/param lists. 1351 if (*I > prec::Comma) 1352 NewParenState.AvoidBinPacking = false; 1353 1354 // Indent from 'LastSpace' unless these are fake parentheses encapsulating 1355 // a builder type call after 'return' or, if the alignment after opening 1356 // brackets is disabled. 1357 if (!Current.isTrailingComment() && 1358 (Style.AlignOperands != FormatStyle::OAS_DontAlign || 1359 *I < prec::Assignment) && 1360 (!Previous || Previous->isNot(tok::kw_return) || 1361 (Style.Language != FormatStyle::LK_Java && *I > 0)) && 1362 (Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign || 1363 *I != prec::Comma || Current.NestingLevel == 0)) { 1364 NewParenState.Indent = 1365 std::max(std::max(State.Column, NewParenState.Indent), 1366 State.Stack.back().LastSpace); 1367 } 1368 1369 if (Previous && 1370 (Previous->getPrecedence() == prec::Assignment || 1371 Previous->is(tok::kw_return) || 1372 (*I == prec::Conditional && Previous->is(tok::question) && 1373 Previous->is(TT_ConditionalExpr))) && 1374 !Newline) { 1375 // If BreakBeforeBinaryOperators is set, un-indent a bit to account for 1376 // the operator and keep the operands aligned 1377 if (Style.AlignOperands == FormatStyle::OAS_AlignAfterOperator) 1378 NewParenState.UnindentOperator = true; 1379 // Mark indentation as alignment if the expression is aligned. 1380 if (Style.AlignOperands != FormatStyle::OAS_DontAlign) 1381 NewParenState.IsAligned = true; 1382 } 1383 1384 // Do not indent relative to the fake parentheses inserted for "." or "->". 1385 // This is a special case to make the following to statements consistent: 1386 // OuterFunction(InnerFunctionCall( // break 1387 // ParameterToInnerFunction)); 1388 // OuterFunction(SomeObject.InnerFunctionCall( // break 1389 // ParameterToInnerFunction)); 1390 if (*I > prec::Unknown) 1391 NewParenState.LastSpace = std::max(NewParenState.LastSpace, State.Column); 1392 if (*I != prec::Conditional && !Current.is(TT_UnaryOperator) && 1393 Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign) 1394 NewParenState.StartOfFunctionCall = State.Column; 1395 1396 // Indent conditional expressions, unless they are chained "else-if" 1397 // conditionals. Never indent expression where the 'operator' is ',', ';' or 1398 // an assignment (i.e. *I <= prec::Assignment) as those have different 1399 // indentation rules. Indent other expression, unless the indentation needs 1400 // to be skipped. 1401 if (*I == prec::Conditional && Previous && Previous->is(tok::colon) && 1402 Previous->is(TT_ConditionalExpr) && I == Current.FakeLParens.rbegin() && 1403 !State.Stack.back().IsWrappedConditional) { 1404 NewParenState.IsChainedConditional = true; 1405 NewParenState.UnindentOperator = State.Stack.back().UnindentOperator; 1406 } else if (*I == prec::Conditional || 1407 (!SkipFirstExtraIndent && *I > prec::Assignment && 1408 !Current.isTrailingComment())) { 1409 NewParenState.Indent += Style.ContinuationIndentWidth; 1410 } 1411 if ((Previous && !Previous->opensScope()) || *I != prec::Comma) 1412 NewParenState.BreakBeforeParameter = false; 1413 State.Stack.push_back(NewParenState); 1414 SkipFirstExtraIndent = false; 1415 } 1416 } 1417 1418 void ContinuationIndenter::moveStatePastFakeRParens(LineState &State) { 1419 for (unsigned i = 0, e = State.NextToken->FakeRParens; i != e; ++i) { 1420 unsigned VariablePos = State.Stack.back().VariablePos; 1421 if (State.Stack.size() == 1) { 1422 // Do not pop the last element. 1423 break; 1424 } 1425 State.Stack.pop_back(); 1426 State.Stack.back().VariablePos = VariablePos; 1427 } 1428 } 1429 1430 void ContinuationIndenter::moveStatePastScopeOpener(LineState &State, 1431 bool Newline) { 1432 const FormatToken &Current = *State.NextToken; 1433 if (!Current.opensScope()) 1434 return; 1435 1436 // Don't allow '<' or '(' in C# generic type constraints to start new scopes. 1437 if (Current.isOneOf(tok::less, tok::l_paren) && 1438 State.Stack.back().IsCSharpGenericTypeConstraint) 1439 return; 1440 1441 if (Current.MatchingParen && Current.is(BK_Block)) { 1442 moveStateToNewBlock(State); 1443 return; 1444 } 1445 1446 unsigned NewIndent; 1447 unsigned LastSpace = State.Stack.back().LastSpace; 1448 bool AvoidBinPacking; 1449 bool BreakBeforeParameter = false; 1450 unsigned NestedBlockIndent = std::max(State.Stack.back().StartOfFunctionCall, 1451 State.Stack.back().NestedBlockIndent); 1452 if (Current.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) || 1453 opensProtoMessageField(Current, Style)) { 1454 if (Current.opensBlockOrBlockTypeList(Style)) { 1455 NewIndent = Style.IndentWidth + 1456 std::min(State.Column, State.Stack.back().NestedBlockIndent); 1457 } else { 1458 NewIndent = State.Stack.back().LastSpace + Style.ContinuationIndentWidth; 1459 } 1460 const FormatToken *NextNoComment = Current.getNextNonComment(); 1461 bool EndsInComma = Current.MatchingParen && 1462 Current.MatchingParen->Previous && 1463 Current.MatchingParen->Previous->is(tok::comma); 1464 AvoidBinPacking = EndsInComma || Current.is(TT_DictLiteral) || 1465 Style.Language == FormatStyle::LK_Proto || 1466 Style.Language == FormatStyle::LK_TextProto || 1467 !Style.BinPackArguments || 1468 (NextNoComment && 1469 NextNoComment->isOneOf(TT_DesignatedInitializerPeriod, 1470 TT_DesignatedInitializerLSquare)); 1471 BreakBeforeParameter = EndsInComma; 1472 if (Current.ParameterCount > 1) 1473 NestedBlockIndent = std::max(NestedBlockIndent, State.Column + 1); 1474 } else { 1475 NewIndent = Style.ContinuationIndentWidth + 1476 std::max(State.Stack.back().LastSpace, 1477 State.Stack.back().StartOfFunctionCall); 1478 1479 // Ensure that different different brackets force relative alignment, e.g.: 1480 // void SomeFunction(vector< // break 1481 // int> v); 1482 // FIXME: We likely want to do this for more combinations of brackets. 1483 if (Current.is(tok::less) && Current.ParentBracket == tok::l_paren) { 1484 NewIndent = std::max(NewIndent, State.Stack.back().Indent); 1485 LastSpace = std::max(LastSpace, State.Stack.back().Indent); 1486 } 1487 1488 bool EndsInComma = 1489 Current.MatchingParen && 1490 Current.MatchingParen->getPreviousNonComment() && 1491 Current.MatchingParen->getPreviousNonComment()->is(tok::comma); 1492 1493 // If ObjCBinPackProtocolList is unspecified, fall back to BinPackParameters 1494 // for backwards compatibility. 1495 bool ObjCBinPackProtocolList = 1496 (Style.ObjCBinPackProtocolList == FormatStyle::BPS_Auto && 1497 Style.BinPackParameters) || 1498 Style.ObjCBinPackProtocolList == FormatStyle::BPS_Always; 1499 1500 bool BinPackDeclaration = 1501 (State.Line->Type != LT_ObjCDecl && Style.BinPackParameters) || 1502 (State.Line->Type == LT_ObjCDecl && ObjCBinPackProtocolList); 1503 1504 AvoidBinPacking = 1505 (State.Stack.back().IsCSharpGenericTypeConstraint) || 1506 (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) || 1507 (State.Line->MustBeDeclaration && !BinPackDeclaration) || 1508 (!State.Line->MustBeDeclaration && !Style.BinPackArguments) || 1509 (Style.ExperimentalAutoDetectBinPacking && 1510 (Current.is(PPK_OnePerLine) || 1511 (!BinPackInconclusiveFunctions && Current.is(PPK_Inconclusive)))); 1512 1513 if (Current.is(TT_ObjCMethodExpr) && Current.MatchingParen && 1514 Style.ObjCBreakBeforeNestedBlockParam) { 1515 if (Style.ColumnLimit) { 1516 // If this '[' opens an ObjC call, determine whether all parameters fit 1517 // into one line and put one per line if they don't. 1518 if (getLengthToMatchingParen(Current, State.Stack) + State.Column > 1519 getColumnLimit(State)) 1520 BreakBeforeParameter = true; 1521 } else { 1522 // For ColumnLimit = 0, we have to figure out whether there is or has to 1523 // be a line break within this call. 1524 for (const FormatToken *Tok = &Current; 1525 Tok && Tok != Current.MatchingParen; Tok = Tok->Next) { 1526 if (Tok->MustBreakBefore || 1527 (Tok->CanBreakBefore && Tok->NewlinesBefore > 0)) { 1528 BreakBeforeParameter = true; 1529 break; 1530 } 1531 } 1532 } 1533 } 1534 1535 if (Style.Language == FormatStyle::LK_JavaScript && EndsInComma) 1536 BreakBeforeParameter = true; 1537 } 1538 // Generally inherit NoLineBreak from the current scope to nested scope. 1539 // However, don't do this for non-empty nested blocks, dict literals and 1540 // array literals as these follow different indentation rules. 1541 bool NoLineBreak = 1542 Current.Children.empty() && 1543 !Current.isOneOf(TT_DictLiteral, TT_ArrayInitializerLSquare) && 1544 (State.Stack.back().NoLineBreak || 1545 State.Stack.back().NoLineBreakInOperand || 1546 (Current.is(TT_TemplateOpener) && 1547 State.Stack.back().ContainsUnwrappedBuilder)); 1548 State.Stack.push_back( 1549 ParenState(&Current, NewIndent, LastSpace, AvoidBinPacking, NoLineBreak)); 1550 State.Stack.back().NestedBlockIndent = NestedBlockIndent; 1551 State.Stack.back().BreakBeforeParameter = BreakBeforeParameter; 1552 State.Stack.back().HasMultipleNestedBlocks = 1553 (Current.BlockParameterCount > 1); 1554 1555 if (Style.BraceWrapping.BeforeLambdaBody && Current.Next != nullptr && 1556 Current.Tok.is(tok::l_paren)) { 1557 // Search for any parameter that is a lambda 1558 FormatToken const *next = Current.Next; 1559 while (next != nullptr) { 1560 if (next->is(TT_LambdaLSquare)) { 1561 State.Stack.back().HasMultipleNestedBlocks = true; 1562 break; 1563 } 1564 next = next->Next; 1565 } 1566 } 1567 1568 State.Stack.back().IsInsideObjCArrayLiteral = 1569 Current.is(TT_ArrayInitializerLSquare) && Current.Previous && 1570 Current.Previous->is(tok::at); 1571 } 1572 1573 void ContinuationIndenter::moveStatePastScopeCloser(LineState &State) { 1574 const FormatToken &Current = *State.NextToken; 1575 if (!Current.closesScope()) 1576 return; 1577 1578 // If we encounter a closing ), ], } or >, we can remove a level from our 1579 // stacks. 1580 if (State.Stack.size() > 1 && 1581 (Current.isOneOf(tok::r_paren, tok::r_square, TT_TemplateString) || 1582 (Current.is(tok::r_brace) && State.NextToken != State.Line->First) || 1583 State.NextToken->is(TT_TemplateCloser) || 1584 (Current.is(tok::greater) && Current.is(TT_DictLiteral)))) 1585 State.Stack.pop_back(); 1586 1587 // Reevaluate whether ObjC message arguments fit into one line. 1588 // If a receiver spans multiple lines, e.g.: 1589 // [[object block:^{ 1590 // return 42; 1591 // }] a:42 b:42]; 1592 // BreakBeforeParameter is calculated based on an incorrect assumption 1593 // (it is checked whether the whole expression fits into one line without 1594 // considering a line break inside a message receiver). 1595 // We check whether arguements fit after receiver scope closer (into the same 1596 // line). 1597 if (State.Stack.back().BreakBeforeParameter && Current.MatchingParen && 1598 Current.MatchingParen->Previous) { 1599 const FormatToken &CurrentScopeOpener = *Current.MatchingParen->Previous; 1600 if (CurrentScopeOpener.is(TT_ObjCMethodExpr) && 1601 CurrentScopeOpener.MatchingParen) { 1602 int NecessarySpaceInLine = 1603 getLengthToMatchingParen(CurrentScopeOpener, State.Stack) + 1604 CurrentScopeOpener.TotalLength - Current.TotalLength - 1; 1605 if (State.Column + Current.ColumnWidth + NecessarySpaceInLine <= 1606 Style.ColumnLimit) 1607 State.Stack.back().BreakBeforeParameter = false; 1608 } 1609 } 1610 1611 if (Current.is(tok::r_square)) { 1612 // If this ends the array subscript expr, reset the corresponding value. 1613 const FormatToken *NextNonComment = Current.getNextNonComment(); 1614 if (NextNonComment && NextNonComment->isNot(tok::l_square)) 1615 State.Stack.back().StartOfArraySubscripts = 0; 1616 } 1617 } 1618 1619 void ContinuationIndenter::moveStateToNewBlock(LineState &State) { 1620 unsigned NestedBlockIndent = State.Stack.back().NestedBlockIndent; 1621 // ObjC block sometimes follow special indentation rules. 1622 unsigned NewIndent = 1623 NestedBlockIndent + (State.NextToken->is(TT_ObjCBlockLBrace) 1624 ? Style.ObjCBlockIndentWidth 1625 : Style.IndentWidth); 1626 State.Stack.push_back(ParenState(State.NextToken, NewIndent, 1627 State.Stack.back().LastSpace, 1628 /*AvoidBinPacking=*/true, 1629 /*NoLineBreak=*/false)); 1630 State.Stack.back().NestedBlockIndent = NestedBlockIndent; 1631 State.Stack.back().BreakBeforeParameter = true; 1632 } 1633 1634 static unsigned getLastLineEndColumn(StringRef Text, unsigned StartColumn, 1635 unsigned TabWidth, 1636 encoding::Encoding Encoding) { 1637 size_t LastNewlinePos = Text.find_last_of("\n"); 1638 if (LastNewlinePos == StringRef::npos) { 1639 return StartColumn + 1640 encoding::columnWidthWithTabs(Text, StartColumn, TabWidth, Encoding); 1641 } else { 1642 return encoding::columnWidthWithTabs(Text.substr(LastNewlinePos), 1643 /*StartColumn=*/0, TabWidth, Encoding); 1644 } 1645 } 1646 1647 unsigned ContinuationIndenter::reformatRawStringLiteral( 1648 const FormatToken &Current, LineState &State, 1649 const FormatStyle &RawStringStyle, bool DryRun, bool Newline) { 1650 unsigned StartColumn = State.Column - Current.ColumnWidth; 1651 StringRef OldDelimiter = *getRawStringDelimiter(Current.TokenText); 1652 StringRef NewDelimiter = 1653 getCanonicalRawStringDelimiter(Style, RawStringStyle.Language); 1654 if (NewDelimiter.empty() || OldDelimiter.empty()) 1655 NewDelimiter = OldDelimiter; 1656 // The text of a raw string is between the leading 'R"delimiter(' and the 1657 // trailing 'delimiter)"'. 1658 unsigned OldPrefixSize = 3 + OldDelimiter.size(); 1659 unsigned OldSuffixSize = 2 + OldDelimiter.size(); 1660 // We create a virtual text environment which expects a null-terminated 1661 // string, so we cannot use StringRef. 1662 std::string RawText = std::string( 1663 Current.TokenText.substr(OldPrefixSize).drop_back(OldSuffixSize)); 1664 if (NewDelimiter != OldDelimiter) { 1665 // Don't update to the canonical delimiter 'deli' if ')deli"' occurs in the 1666 // raw string. 1667 std::string CanonicalDelimiterSuffix = (")" + NewDelimiter + "\"").str(); 1668 if (StringRef(RawText).contains(CanonicalDelimiterSuffix)) 1669 NewDelimiter = OldDelimiter; 1670 } 1671 1672 unsigned NewPrefixSize = 3 + NewDelimiter.size(); 1673 unsigned NewSuffixSize = 2 + NewDelimiter.size(); 1674 1675 // The first start column is the column the raw text starts after formatting. 1676 unsigned FirstStartColumn = StartColumn + NewPrefixSize; 1677 1678 // The next start column is the intended indentation a line break inside 1679 // the raw string at level 0. It is determined by the following rules: 1680 // - if the content starts on newline, it is one level more than the current 1681 // indent, and 1682 // - if the content does not start on a newline, it is the first start 1683 // column. 1684 // These rules have the advantage that the formatted content both does not 1685 // violate the rectangle rule and visually flows within the surrounding 1686 // source. 1687 bool ContentStartsOnNewline = Current.TokenText[OldPrefixSize] == '\n'; 1688 // If this token is the last parameter (checked by looking if it's followed by 1689 // `)` and is not on a newline, the base the indent off the line's nested 1690 // block indent. Otherwise, base the indent off the arguments indent, so we 1691 // can achieve: 1692 // 1693 // fffffffffff(1, 2, 3, R"pb( 1694 // key1: 1 # 1695 // key2: 2)pb"); 1696 // 1697 // fffffffffff(1, 2, 3, 1698 // R"pb( 1699 // key1: 1 # 1700 // key2: 2 1701 // )pb"); 1702 // 1703 // fffffffffff(1, 2, 3, 1704 // R"pb( 1705 // key1: 1 # 1706 // key2: 2 1707 // )pb", 1708 // 5); 1709 unsigned CurrentIndent = 1710 (!Newline && Current.Next && Current.Next->is(tok::r_paren)) 1711 ? State.Stack.back().NestedBlockIndent 1712 : State.Stack.back().Indent; 1713 unsigned NextStartColumn = ContentStartsOnNewline 1714 ? CurrentIndent + Style.IndentWidth 1715 : FirstStartColumn; 1716 1717 // The last start column is the column the raw string suffix starts if it is 1718 // put on a newline. 1719 // The last start column is the intended indentation of the raw string postfix 1720 // if it is put on a newline. It is determined by the following rules: 1721 // - if the raw string prefix starts on a newline, it is the column where 1722 // that raw string prefix starts, and 1723 // - if the raw string prefix does not start on a newline, it is the current 1724 // indent. 1725 unsigned LastStartColumn = 1726 Current.NewlinesBefore ? FirstStartColumn - NewPrefixSize : CurrentIndent; 1727 1728 std::pair<tooling::Replacements, unsigned> Fixes = internal::reformat( 1729 RawStringStyle, RawText, {tooling::Range(0, RawText.size())}, 1730 FirstStartColumn, NextStartColumn, LastStartColumn, "<stdin>", 1731 /*Status=*/nullptr); 1732 1733 auto NewCode = applyAllReplacements(RawText, Fixes.first); 1734 tooling::Replacements NoFixes; 1735 if (!NewCode) { 1736 return addMultilineToken(Current, State); 1737 } 1738 if (!DryRun) { 1739 if (NewDelimiter != OldDelimiter) { 1740 // In 'R"delimiter(...', the delimiter starts 2 characters after the start 1741 // of the token. 1742 SourceLocation PrefixDelimiterStart = 1743 Current.Tok.getLocation().getLocWithOffset(2); 1744 auto PrefixErr = Whitespaces.addReplacement(tooling::Replacement( 1745 SourceMgr, PrefixDelimiterStart, OldDelimiter.size(), NewDelimiter)); 1746 if (PrefixErr) { 1747 llvm::errs() 1748 << "Failed to update the prefix delimiter of a raw string: " 1749 << llvm::toString(std::move(PrefixErr)) << "\n"; 1750 } 1751 // In 'R"delimiter(...)delimiter"', the suffix delimiter starts at 1752 // position length - 1 - |delimiter|. 1753 SourceLocation SuffixDelimiterStart = 1754 Current.Tok.getLocation().getLocWithOffset(Current.TokenText.size() - 1755 1 - OldDelimiter.size()); 1756 auto SuffixErr = Whitespaces.addReplacement(tooling::Replacement( 1757 SourceMgr, SuffixDelimiterStart, OldDelimiter.size(), NewDelimiter)); 1758 if (SuffixErr) { 1759 llvm::errs() 1760 << "Failed to update the suffix delimiter of a raw string: " 1761 << llvm::toString(std::move(SuffixErr)) << "\n"; 1762 } 1763 } 1764 SourceLocation OriginLoc = 1765 Current.Tok.getLocation().getLocWithOffset(OldPrefixSize); 1766 for (const tooling::Replacement &Fix : Fixes.first) { 1767 auto Err = Whitespaces.addReplacement(tooling::Replacement( 1768 SourceMgr, OriginLoc.getLocWithOffset(Fix.getOffset()), 1769 Fix.getLength(), Fix.getReplacementText())); 1770 if (Err) { 1771 llvm::errs() << "Failed to reformat raw string: " 1772 << llvm::toString(std::move(Err)) << "\n"; 1773 } 1774 } 1775 } 1776 unsigned RawLastLineEndColumn = getLastLineEndColumn( 1777 *NewCode, FirstStartColumn, Style.TabWidth, Encoding); 1778 State.Column = RawLastLineEndColumn + NewSuffixSize; 1779 // Since we're updating the column to after the raw string literal here, we 1780 // have to manually add the penalty for the prefix R"delim( over the column 1781 // limit. 1782 unsigned PrefixExcessCharacters = 1783 StartColumn + NewPrefixSize > Style.ColumnLimit 1784 ? StartColumn + NewPrefixSize - Style.ColumnLimit 1785 : 0; 1786 bool IsMultiline = 1787 ContentStartsOnNewline || (NewCode->find('\n') != std::string::npos); 1788 if (IsMultiline) { 1789 // Break before further function parameters on all levels. 1790 for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) 1791 State.Stack[i].BreakBeforeParameter = true; 1792 } 1793 return Fixes.second + PrefixExcessCharacters * Style.PenaltyExcessCharacter; 1794 } 1795 1796 unsigned ContinuationIndenter::addMultilineToken(const FormatToken &Current, 1797 LineState &State) { 1798 // Break before further function parameters on all levels. 1799 for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) 1800 State.Stack[i].BreakBeforeParameter = true; 1801 1802 unsigned ColumnsUsed = State.Column; 1803 // We can only affect layout of the first and the last line, so the penalty 1804 // for all other lines is constant, and we ignore it. 1805 State.Column = Current.LastLineColumnWidth; 1806 1807 if (ColumnsUsed > getColumnLimit(State)) 1808 return Style.PenaltyExcessCharacter * (ColumnsUsed - getColumnLimit(State)); 1809 return 0; 1810 } 1811 1812 unsigned ContinuationIndenter::handleEndOfLine(const FormatToken &Current, 1813 LineState &State, bool DryRun, 1814 bool AllowBreak, bool Newline) { 1815 unsigned Penalty = 0; 1816 // Compute the raw string style to use in case this is a raw string literal 1817 // that can be reformatted. 1818 auto RawStringStyle = getRawStringStyle(Current, State); 1819 if (RawStringStyle && !Current.Finalized) { 1820 Penalty = reformatRawStringLiteral(Current, State, *RawStringStyle, DryRun, 1821 Newline); 1822 } else if (Current.IsMultiline && Current.isNot(TT_BlockComment)) { 1823 // Don't break multi-line tokens other than block comments and raw string 1824 // literals. Instead, just update the state. 1825 Penalty = addMultilineToken(Current, State); 1826 } else if (State.Line->Type != LT_ImportStatement) { 1827 // We generally don't break import statements. 1828 LineState OriginalState = State; 1829 1830 // Whether we force the reflowing algorithm to stay strictly within the 1831 // column limit. 1832 bool Strict = false; 1833 // Whether the first non-strict attempt at reflowing did intentionally 1834 // exceed the column limit. 1835 bool Exceeded = false; 1836 std::tie(Penalty, Exceeded) = breakProtrudingToken( 1837 Current, State, AllowBreak, /*DryRun=*/true, Strict); 1838 if (Exceeded) { 1839 // If non-strict reflowing exceeds the column limit, try whether strict 1840 // reflowing leads to an overall lower penalty. 1841 LineState StrictState = OriginalState; 1842 unsigned StrictPenalty = 1843 breakProtrudingToken(Current, StrictState, AllowBreak, 1844 /*DryRun=*/true, /*Strict=*/true) 1845 .first; 1846 Strict = StrictPenalty <= Penalty; 1847 if (Strict) { 1848 Penalty = StrictPenalty; 1849 State = StrictState; 1850 } 1851 } 1852 if (!DryRun) { 1853 // If we're not in dry-run mode, apply the changes with the decision on 1854 // strictness made above. 1855 breakProtrudingToken(Current, OriginalState, AllowBreak, /*DryRun=*/false, 1856 Strict); 1857 } 1858 } 1859 if (State.Column > getColumnLimit(State)) { 1860 unsigned ExcessCharacters = State.Column - getColumnLimit(State); 1861 Penalty += Style.PenaltyExcessCharacter * ExcessCharacters; 1862 } 1863 return Penalty; 1864 } 1865 1866 // Returns the enclosing function name of a token, or the empty string if not 1867 // found. 1868 static StringRef getEnclosingFunctionName(const FormatToken &Current) { 1869 // Look for: 'function(' or 'function<templates>(' before Current. 1870 auto Tok = Current.getPreviousNonComment(); 1871 if (!Tok || !Tok->is(tok::l_paren)) 1872 return ""; 1873 Tok = Tok->getPreviousNonComment(); 1874 if (!Tok) 1875 return ""; 1876 if (Tok->is(TT_TemplateCloser)) { 1877 Tok = Tok->MatchingParen; 1878 if (Tok) 1879 Tok = Tok->getPreviousNonComment(); 1880 } 1881 if (!Tok || !Tok->is(tok::identifier)) 1882 return ""; 1883 return Tok->TokenText; 1884 } 1885 1886 llvm::Optional<FormatStyle> 1887 ContinuationIndenter::getRawStringStyle(const FormatToken &Current, 1888 const LineState &State) { 1889 if (!Current.isStringLiteral()) 1890 return None; 1891 auto Delimiter = getRawStringDelimiter(Current.TokenText); 1892 if (!Delimiter) 1893 return None; 1894 auto RawStringStyle = RawStringFormats.getDelimiterStyle(*Delimiter); 1895 if (!RawStringStyle && Delimiter->empty()) 1896 RawStringStyle = RawStringFormats.getEnclosingFunctionStyle( 1897 getEnclosingFunctionName(Current)); 1898 if (!RawStringStyle) 1899 return None; 1900 RawStringStyle->ColumnLimit = getColumnLimit(State); 1901 return RawStringStyle; 1902 } 1903 1904 std::unique_ptr<BreakableToken> 1905 ContinuationIndenter::createBreakableToken(const FormatToken &Current, 1906 LineState &State, bool AllowBreak) { 1907 unsigned StartColumn = State.Column - Current.ColumnWidth; 1908 if (Current.isStringLiteral()) { 1909 // FIXME: String literal breaking is currently disabled for C#, Java and 1910 // JavaScript, as it requires strings to be merged using "+" which we 1911 // don't support. 1912 if (Style.Language == FormatStyle::LK_Java || 1913 Style.Language == FormatStyle::LK_JavaScript || Style.isCSharp() || 1914 !Style.BreakStringLiterals || !AllowBreak) 1915 return nullptr; 1916 1917 // Don't break string literals inside preprocessor directives (except for 1918 // #define directives, as their contents are stored in separate lines and 1919 // are not affected by this check). 1920 // This way we avoid breaking code with line directives and unknown 1921 // preprocessor directives that contain long string literals. 1922 if (State.Line->Type == LT_PreprocessorDirective) 1923 return nullptr; 1924 // Exempts unterminated string literals from line breaking. The user will 1925 // likely want to terminate the string before any line breaking is done. 1926 if (Current.IsUnterminatedLiteral) 1927 return nullptr; 1928 // Don't break string literals inside Objective-C array literals (doing so 1929 // raises the warning -Wobjc-string-concatenation). 1930 if (State.Stack.back().IsInsideObjCArrayLiteral) { 1931 return nullptr; 1932 } 1933 1934 StringRef Text = Current.TokenText; 1935 StringRef Prefix; 1936 StringRef Postfix; 1937 // FIXME: Handle whitespace between '_T', '(', '"..."', and ')'. 1938 // FIXME: Store Prefix and Suffix (or PrefixLength and SuffixLength to 1939 // reduce the overhead) for each FormatToken, which is a string, so that we 1940 // don't run multiple checks here on the hot path. 1941 if ((Text.endswith(Postfix = "\"") && 1942 (Text.startswith(Prefix = "@\"") || Text.startswith(Prefix = "\"") || 1943 Text.startswith(Prefix = "u\"") || Text.startswith(Prefix = "U\"") || 1944 Text.startswith(Prefix = "u8\"") || 1945 Text.startswith(Prefix = "L\""))) || 1946 (Text.startswith(Prefix = "_T(\"") && Text.endswith(Postfix = "\")"))) { 1947 // We need this to address the case where there is an unbreakable tail 1948 // only if certain other formatting decisions have been taken. The 1949 // UnbreakableTailLength of Current is an overapproximation is that case 1950 // and we need to be correct here. 1951 unsigned UnbreakableTailLength = (State.NextToken && canBreak(State)) 1952 ? 0 1953 : Current.UnbreakableTailLength; 1954 return std::make_unique<BreakableStringLiteral>( 1955 Current, StartColumn, Prefix, Postfix, UnbreakableTailLength, 1956 State.Line->InPPDirective, Encoding, Style); 1957 } 1958 } else if (Current.is(TT_BlockComment)) { 1959 if (!Style.ReflowComments || 1960 // If a comment token switches formatting, like 1961 // /* clang-format on */, we don't want to break it further, 1962 // but we may still want to adjust its indentation. 1963 switchesFormatting(Current)) { 1964 return nullptr; 1965 } 1966 return std::make_unique<BreakableBlockComment>( 1967 Current, StartColumn, Current.OriginalColumn, !Current.Previous, 1968 State.Line->InPPDirective, Encoding, Style, Whitespaces.useCRLF()); 1969 } else if (Current.is(TT_LineComment) && 1970 (Current.Previous == nullptr || 1971 Current.Previous->isNot(TT_ImplicitStringLiteral))) { 1972 if (!Style.ReflowComments || 1973 CommentPragmasRegex.match(Current.TokenText.substr(2)) || 1974 switchesFormatting(Current)) 1975 return nullptr; 1976 return std::make_unique<BreakableLineCommentSection>( 1977 Current, StartColumn, /*InPPDirective=*/false, Encoding, Style); 1978 } 1979 return nullptr; 1980 } 1981 1982 std::pair<unsigned, bool> 1983 ContinuationIndenter::breakProtrudingToken(const FormatToken &Current, 1984 LineState &State, bool AllowBreak, 1985 bool DryRun, bool Strict) { 1986 std::unique_ptr<const BreakableToken> Token = 1987 createBreakableToken(Current, State, AllowBreak); 1988 if (!Token) 1989 return {0, false}; 1990 assert(Token->getLineCount() > 0); 1991 unsigned ColumnLimit = getColumnLimit(State); 1992 if (Current.is(TT_LineComment)) { 1993 // We don't insert backslashes when breaking line comments. 1994 ColumnLimit = Style.ColumnLimit; 1995 } 1996 if (Current.UnbreakableTailLength >= ColumnLimit) 1997 return {0, false}; 1998 // ColumnWidth was already accounted into State.Column before calling 1999 // breakProtrudingToken. 2000 unsigned StartColumn = State.Column - Current.ColumnWidth; 2001 unsigned NewBreakPenalty = Current.isStringLiteral() 2002 ? Style.PenaltyBreakString 2003 : Style.PenaltyBreakComment; 2004 // Stores whether we intentionally decide to let a line exceed the column 2005 // limit. 2006 bool Exceeded = false; 2007 // Stores whether we introduce a break anywhere in the token. 2008 bool BreakInserted = Token->introducesBreakBeforeToken(); 2009 // Store whether we inserted a new line break at the end of the previous 2010 // logical line. 2011 bool NewBreakBefore = false; 2012 // We use a conservative reflowing strategy. Reflow starts after a line is 2013 // broken or the corresponding whitespace compressed. Reflow ends as soon as a 2014 // line that doesn't get reflown with the previous line is reached. 2015 bool Reflow = false; 2016 // Keep track of where we are in the token: 2017 // Where we are in the content of the current logical line. 2018 unsigned TailOffset = 0; 2019 // The column number we're currently at. 2020 unsigned ContentStartColumn = 2021 Token->getContentStartColumn(0, /*Break=*/false); 2022 // The number of columns left in the current logical line after TailOffset. 2023 unsigned RemainingTokenColumns = 2024 Token->getRemainingLength(0, TailOffset, ContentStartColumn); 2025 // Adapt the start of the token, for example indent. 2026 if (!DryRun) 2027 Token->adaptStartOfLine(0, Whitespaces); 2028 2029 unsigned ContentIndent = 0; 2030 unsigned Penalty = 0; 2031 LLVM_DEBUG(llvm::dbgs() << "Breaking protruding token at column " 2032 << StartColumn << ".\n"); 2033 for (unsigned LineIndex = 0, EndIndex = Token->getLineCount(); 2034 LineIndex != EndIndex; ++LineIndex) { 2035 LLVM_DEBUG(llvm::dbgs() 2036 << " Line: " << LineIndex << " (Reflow: " << Reflow << ")\n"); 2037 NewBreakBefore = false; 2038 // If we did reflow the previous line, we'll try reflowing again. Otherwise 2039 // we'll start reflowing if the current line is broken or whitespace is 2040 // compressed. 2041 bool TryReflow = Reflow; 2042 // Break the current token until we can fit the rest of the line. 2043 while (ContentStartColumn + RemainingTokenColumns > ColumnLimit) { 2044 LLVM_DEBUG(llvm::dbgs() << " Over limit, need: " 2045 << (ContentStartColumn + RemainingTokenColumns) 2046 << ", space: " << ColumnLimit 2047 << ", reflown prefix: " << ContentStartColumn 2048 << ", offset in line: " << TailOffset << "\n"); 2049 // If the current token doesn't fit, find the latest possible split in the 2050 // current line so that breaking at it will be under the column limit. 2051 // FIXME: Use the earliest possible split while reflowing to correctly 2052 // compress whitespace within a line. 2053 BreakableToken::Split Split = 2054 Token->getSplit(LineIndex, TailOffset, ColumnLimit, 2055 ContentStartColumn, CommentPragmasRegex); 2056 if (Split.first == StringRef::npos) { 2057 // No break opportunity - update the penalty and continue with the next 2058 // logical line. 2059 if (LineIndex < EndIndex - 1) 2060 // The last line's penalty is handled in addNextStateToQueue() or when 2061 // calling replaceWhitespaceAfterLastLine below. 2062 Penalty += Style.PenaltyExcessCharacter * 2063 (ContentStartColumn + RemainingTokenColumns - ColumnLimit); 2064 LLVM_DEBUG(llvm::dbgs() << " No break opportunity.\n"); 2065 break; 2066 } 2067 assert(Split.first != 0); 2068 2069 if (Token->supportsReflow()) { 2070 // Check whether the next natural split point after the current one can 2071 // still fit the line, either because we can compress away whitespace, 2072 // or because the penalty the excess characters introduce is lower than 2073 // the break penalty. 2074 // We only do this for tokens that support reflowing, and thus allow us 2075 // to change the whitespace arbitrarily (e.g. comments). 2076 // Other tokens, like string literals, can be broken on arbitrary 2077 // positions. 2078 2079 // First, compute the columns from TailOffset to the next possible split 2080 // position. 2081 // For example: 2082 // ColumnLimit: | 2083 // // Some text that breaks 2084 // ^ tail offset 2085 // ^-- split 2086 // ^-------- to split columns 2087 // ^--- next split 2088 // ^--------------- to next split columns 2089 unsigned ToSplitColumns = Token->getRangeLength( 2090 LineIndex, TailOffset, Split.first, ContentStartColumn); 2091 LLVM_DEBUG(llvm::dbgs() << " ToSplit: " << ToSplitColumns << "\n"); 2092 2093 BreakableToken::Split NextSplit = Token->getSplit( 2094 LineIndex, TailOffset + Split.first + Split.second, ColumnLimit, 2095 ContentStartColumn + ToSplitColumns + 1, CommentPragmasRegex); 2096 // Compute the columns necessary to fit the next non-breakable sequence 2097 // into the current line. 2098 unsigned ToNextSplitColumns = 0; 2099 if (NextSplit.first == StringRef::npos) { 2100 ToNextSplitColumns = Token->getRemainingLength(LineIndex, TailOffset, 2101 ContentStartColumn); 2102 } else { 2103 ToNextSplitColumns = Token->getRangeLength( 2104 LineIndex, TailOffset, 2105 Split.first + Split.second + NextSplit.first, ContentStartColumn); 2106 } 2107 // Compress the whitespace between the break and the start of the next 2108 // unbreakable sequence. 2109 ToNextSplitColumns = 2110 Token->getLengthAfterCompression(ToNextSplitColumns, Split); 2111 LLVM_DEBUG(llvm::dbgs() 2112 << " ContentStartColumn: " << ContentStartColumn << "\n"); 2113 LLVM_DEBUG(llvm::dbgs() 2114 << " ToNextSplit: " << ToNextSplitColumns << "\n"); 2115 // If the whitespace compression makes us fit, continue on the current 2116 // line. 2117 bool ContinueOnLine = 2118 ContentStartColumn + ToNextSplitColumns <= ColumnLimit; 2119 unsigned ExcessCharactersPenalty = 0; 2120 if (!ContinueOnLine && !Strict) { 2121 // Similarly, if the excess characters' penalty is lower than the 2122 // penalty of introducing a new break, continue on the current line. 2123 ExcessCharactersPenalty = 2124 (ContentStartColumn + ToNextSplitColumns - ColumnLimit) * 2125 Style.PenaltyExcessCharacter; 2126 LLVM_DEBUG(llvm::dbgs() 2127 << " Penalty excess: " << ExcessCharactersPenalty 2128 << "\n break : " << NewBreakPenalty << "\n"); 2129 if (ExcessCharactersPenalty < NewBreakPenalty) { 2130 Exceeded = true; 2131 ContinueOnLine = true; 2132 } 2133 } 2134 if (ContinueOnLine) { 2135 LLVM_DEBUG(llvm::dbgs() << " Continuing on line...\n"); 2136 // The current line fits after compressing the whitespace - reflow 2137 // the next line into it if possible. 2138 TryReflow = true; 2139 if (!DryRun) 2140 Token->compressWhitespace(LineIndex, TailOffset, Split, 2141 Whitespaces); 2142 // When we continue on the same line, leave one space between content. 2143 ContentStartColumn += ToSplitColumns + 1; 2144 Penalty += ExcessCharactersPenalty; 2145 TailOffset += Split.first + Split.second; 2146 RemainingTokenColumns = Token->getRemainingLength( 2147 LineIndex, TailOffset, ContentStartColumn); 2148 continue; 2149 } 2150 } 2151 LLVM_DEBUG(llvm::dbgs() << " Breaking...\n"); 2152 // Update the ContentIndent only if the current line was not reflown with 2153 // the previous line, since in that case the previous line should still 2154 // determine the ContentIndent. Also never intent the last line. 2155 if (!Reflow) 2156 ContentIndent = Token->getContentIndent(LineIndex); 2157 LLVM_DEBUG(llvm::dbgs() 2158 << " ContentIndent: " << ContentIndent << "\n"); 2159 ContentStartColumn = ContentIndent + Token->getContentStartColumn( 2160 LineIndex, /*Break=*/true); 2161 2162 unsigned NewRemainingTokenColumns = Token->getRemainingLength( 2163 LineIndex, TailOffset + Split.first + Split.second, 2164 ContentStartColumn); 2165 if (NewRemainingTokenColumns == 0) { 2166 // No content to indent. 2167 ContentIndent = 0; 2168 ContentStartColumn = 2169 Token->getContentStartColumn(LineIndex, /*Break=*/true); 2170 NewRemainingTokenColumns = Token->getRemainingLength( 2171 LineIndex, TailOffset + Split.first + Split.second, 2172 ContentStartColumn); 2173 } 2174 2175 // When breaking before a tab character, it may be moved by a few columns, 2176 // but will still be expanded to the next tab stop, so we don't save any 2177 // columns. 2178 if (NewRemainingTokenColumns == RemainingTokenColumns) { 2179 // FIXME: Do we need to adjust the penalty? 2180 break; 2181 } 2182 assert(NewRemainingTokenColumns < RemainingTokenColumns); 2183 2184 LLVM_DEBUG(llvm::dbgs() << " Breaking at: " << TailOffset + Split.first 2185 << ", " << Split.second << "\n"); 2186 if (!DryRun) 2187 Token->insertBreak(LineIndex, TailOffset, Split, ContentIndent, 2188 Whitespaces); 2189 2190 Penalty += NewBreakPenalty; 2191 TailOffset += Split.first + Split.second; 2192 RemainingTokenColumns = NewRemainingTokenColumns; 2193 BreakInserted = true; 2194 NewBreakBefore = true; 2195 } 2196 // In case there's another line, prepare the state for the start of the next 2197 // line. 2198 if (LineIndex + 1 != EndIndex) { 2199 unsigned NextLineIndex = LineIndex + 1; 2200 if (NewBreakBefore) 2201 // After breaking a line, try to reflow the next line into the current 2202 // one once RemainingTokenColumns fits. 2203 TryReflow = true; 2204 if (TryReflow) { 2205 // We decided that we want to try reflowing the next line into the 2206 // current one. 2207 // We will now adjust the state as if the reflow is successful (in 2208 // preparation for the next line), and see whether that works. If we 2209 // decide that we cannot reflow, we will later reset the state to the 2210 // start of the next line. 2211 Reflow = false; 2212 // As we did not continue breaking the line, RemainingTokenColumns is 2213 // known to fit after ContentStartColumn. Adapt ContentStartColumn to 2214 // the position at which we want to format the next line if we do 2215 // actually reflow. 2216 // When we reflow, we need to add a space between the end of the current 2217 // line and the next line's start column. 2218 ContentStartColumn += RemainingTokenColumns + 1; 2219 // Get the split that we need to reflow next logical line into the end 2220 // of the current one; the split will include any leading whitespace of 2221 // the next logical line. 2222 BreakableToken::Split SplitBeforeNext = 2223 Token->getReflowSplit(NextLineIndex, CommentPragmasRegex); 2224 LLVM_DEBUG(llvm::dbgs() 2225 << " Size of reflown text: " << ContentStartColumn 2226 << "\n Potential reflow split: "); 2227 if (SplitBeforeNext.first != StringRef::npos) { 2228 LLVM_DEBUG(llvm::dbgs() << SplitBeforeNext.first << ", " 2229 << SplitBeforeNext.second << "\n"); 2230 TailOffset = SplitBeforeNext.first + SplitBeforeNext.second; 2231 // If the rest of the next line fits into the current line below the 2232 // column limit, we can safely reflow. 2233 RemainingTokenColumns = Token->getRemainingLength( 2234 NextLineIndex, TailOffset, ContentStartColumn); 2235 Reflow = true; 2236 if (ContentStartColumn + RemainingTokenColumns > ColumnLimit) { 2237 LLVM_DEBUG(llvm::dbgs() 2238 << " Over limit after reflow, need: " 2239 << (ContentStartColumn + RemainingTokenColumns) 2240 << ", space: " << ColumnLimit 2241 << ", reflown prefix: " << ContentStartColumn 2242 << ", offset in line: " << TailOffset << "\n"); 2243 // If the whole next line does not fit, try to find a point in 2244 // the next line at which we can break so that attaching the part 2245 // of the next line to that break point onto the current line is 2246 // below the column limit. 2247 BreakableToken::Split Split = 2248 Token->getSplit(NextLineIndex, TailOffset, ColumnLimit, 2249 ContentStartColumn, CommentPragmasRegex); 2250 if (Split.first == StringRef::npos) { 2251 LLVM_DEBUG(llvm::dbgs() << " Did not find later break\n"); 2252 Reflow = false; 2253 } else { 2254 // Check whether the first split point gets us below the column 2255 // limit. Note that we will execute this split below as part of 2256 // the normal token breaking and reflow logic within the line. 2257 unsigned ToSplitColumns = Token->getRangeLength( 2258 NextLineIndex, TailOffset, Split.first, ContentStartColumn); 2259 if (ContentStartColumn + ToSplitColumns > ColumnLimit) { 2260 LLVM_DEBUG(llvm::dbgs() << " Next split protrudes, need: " 2261 << (ContentStartColumn + ToSplitColumns) 2262 << ", space: " << ColumnLimit); 2263 unsigned ExcessCharactersPenalty = 2264 (ContentStartColumn + ToSplitColumns - ColumnLimit) * 2265 Style.PenaltyExcessCharacter; 2266 if (NewBreakPenalty < ExcessCharactersPenalty) { 2267 Reflow = false; 2268 } 2269 } 2270 } 2271 } 2272 } else { 2273 LLVM_DEBUG(llvm::dbgs() << "not found.\n"); 2274 } 2275 } 2276 if (!Reflow) { 2277 // If we didn't reflow into the next line, the only space to consider is 2278 // the next logical line. Reset our state to match the start of the next 2279 // line. 2280 TailOffset = 0; 2281 ContentStartColumn = 2282 Token->getContentStartColumn(NextLineIndex, /*Break=*/false); 2283 RemainingTokenColumns = Token->getRemainingLength( 2284 NextLineIndex, TailOffset, ContentStartColumn); 2285 // Adapt the start of the token, for example indent. 2286 if (!DryRun) 2287 Token->adaptStartOfLine(NextLineIndex, Whitespaces); 2288 } else { 2289 // If we found a reflow split and have added a new break before the next 2290 // line, we are going to remove the line break at the start of the next 2291 // logical line. For example, here we'll add a new line break after 2292 // 'text', and subsequently delete the line break between 'that' and 2293 // 'reflows'. 2294 // // some text that 2295 // // reflows 2296 // -> 2297 // // some text 2298 // // that reflows 2299 // When adding the line break, we also added the penalty for it, so we 2300 // need to subtract that penalty again when we remove the line break due 2301 // to reflowing. 2302 if (NewBreakBefore) { 2303 assert(Penalty >= NewBreakPenalty); 2304 Penalty -= NewBreakPenalty; 2305 } 2306 if (!DryRun) 2307 Token->reflow(NextLineIndex, Whitespaces); 2308 } 2309 } 2310 } 2311 2312 BreakableToken::Split SplitAfterLastLine = 2313 Token->getSplitAfterLastLine(TailOffset); 2314 if (SplitAfterLastLine.first != StringRef::npos) { 2315 LLVM_DEBUG(llvm::dbgs() << "Replacing whitespace after last line.\n"); 2316 2317 // We add the last line's penalty here, since that line is going to be split 2318 // now. 2319 Penalty += Style.PenaltyExcessCharacter * 2320 (ContentStartColumn + RemainingTokenColumns - ColumnLimit); 2321 2322 if (!DryRun) 2323 Token->replaceWhitespaceAfterLastLine(TailOffset, SplitAfterLastLine, 2324 Whitespaces); 2325 ContentStartColumn = 2326 Token->getContentStartColumn(Token->getLineCount() - 1, /*Break=*/true); 2327 RemainingTokenColumns = Token->getRemainingLength( 2328 Token->getLineCount() - 1, 2329 TailOffset + SplitAfterLastLine.first + SplitAfterLastLine.second, 2330 ContentStartColumn); 2331 } 2332 2333 State.Column = ContentStartColumn + RemainingTokenColumns - 2334 Current.UnbreakableTailLength; 2335 2336 if (BreakInserted) { 2337 // If we break the token inside a parameter list, we need to break before 2338 // the next parameter on all levels, so that the next parameter is clearly 2339 // visible. Line comments already introduce a break. 2340 if (Current.isNot(TT_LineComment)) { 2341 for (unsigned i = 0, e = State.Stack.size(); i != e; ++i) 2342 State.Stack[i].BreakBeforeParameter = true; 2343 } 2344 2345 if (Current.is(TT_BlockComment)) 2346 State.NoContinuation = true; 2347 2348 State.Stack.back().LastSpace = StartColumn; 2349 } 2350 2351 Token->updateNextToken(State); 2352 2353 return {Penalty, Exceeded}; 2354 } 2355 2356 unsigned ContinuationIndenter::getColumnLimit(const LineState &State) const { 2357 // In preprocessor directives reserve two chars for trailing " \" 2358 return Style.ColumnLimit - (State.Line->InPPDirective ? 2 : 0); 2359 } 2360 2361 bool ContinuationIndenter::nextIsMultilineString(const LineState &State) { 2362 const FormatToken &Current = *State.NextToken; 2363 if (!Current.isStringLiteral() || Current.is(TT_ImplicitStringLiteral)) 2364 return false; 2365 // We never consider raw string literals "multiline" for the purpose of 2366 // AlwaysBreakBeforeMultilineStrings implementation as they are special-cased 2367 // (see TokenAnnotator::mustBreakBefore(). 2368 if (Current.TokenText.startswith("R\"")) 2369 return false; 2370 if (Current.IsMultiline) 2371 return true; 2372 if (Current.getNextNonComment() && 2373 Current.getNextNonComment()->isStringLiteral()) 2374 return true; // Implicit concatenation. 2375 if (Style.ColumnLimit != 0 && Style.BreakStringLiterals && 2376 State.Column + Current.ColumnWidth + Current.UnbreakableTailLength > 2377 Style.ColumnLimit) 2378 return true; // String will be split. 2379 return false; 2380 } 2381 2382 } // namespace format 2383 } // namespace clang 2384