1 //===--- UnwrappedLineParser.cpp - Format C++ code ------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// \brief This file contains the implementation of the UnwrappedLineParser,
12 /// which turns a stream of tokens into UnwrappedLines.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "UnwrappedLineParser.h"
17 #include "llvm/Support/Debug.h"
18 
19 #define DEBUG_TYPE "format-parser"
20 
21 namespace clang {
22 namespace format {
23 
24 class FormatTokenSource {
25 public:
26   virtual ~FormatTokenSource() {}
27   virtual FormatToken *getNextToken() = 0;
28 
29   virtual unsigned getPosition() = 0;
30   virtual FormatToken *setPosition(unsigned Position) = 0;
31 };
32 
33 namespace {
34 
35 class ScopedDeclarationState {
36 public:
37   ScopedDeclarationState(UnwrappedLine &Line, std::vector<bool> &Stack,
38                          bool MustBeDeclaration)
39       : Line(Line), Stack(Stack) {
40     Line.MustBeDeclaration = MustBeDeclaration;
41     Stack.push_back(MustBeDeclaration);
42   }
43   ~ScopedDeclarationState() {
44     Stack.pop_back();
45     if (!Stack.empty())
46       Line.MustBeDeclaration = Stack.back();
47     else
48       Line.MustBeDeclaration = true;
49   }
50 
51 private:
52   UnwrappedLine &Line;
53   std::vector<bool> &Stack;
54 };
55 
56 class ScopedMacroState : public FormatTokenSource {
57 public:
58   ScopedMacroState(UnwrappedLine &Line, FormatTokenSource *&TokenSource,
59                    FormatToken *&ResetToken, bool &StructuralError)
60       : Line(Line), TokenSource(TokenSource), ResetToken(ResetToken),
61         PreviousLineLevel(Line.Level), PreviousTokenSource(TokenSource),
62         StructuralError(StructuralError),
63         PreviousStructuralError(StructuralError), Token(nullptr) {
64     TokenSource = this;
65     Line.Level = 0;
66     Line.InPPDirective = true;
67   }
68 
69   ~ScopedMacroState() {
70     TokenSource = PreviousTokenSource;
71     ResetToken = Token;
72     Line.InPPDirective = false;
73     Line.Level = PreviousLineLevel;
74     StructuralError = PreviousStructuralError;
75   }
76 
77   FormatToken *getNextToken() override {
78     // The \c UnwrappedLineParser guards against this by never calling
79     // \c getNextToken() after it has encountered the first eof token.
80     assert(!eof());
81     Token = PreviousTokenSource->getNextToken();
82     if (eof())
83       return getFakeEOF();
84     return Token;
85   }
86 
87   unsigned getPosition() override { return PreviousTokenSource->getPosition(); }
88 
89   FormatToken *setPosition(unsigned Position) override {
90     Token = PreviousTokenSource->setPosition(Position);
91     return Token;
92   }
93 
94 private:
95   bool eof() { return Token && Token->HasUnescapedNewline; }
96 
97   FormatToken *getFakeEOF() {
98     static bool EOFInitialized = false;
99     static FormatToken FormatTok;
100     if (!EOFInitialized) {
101       FormatTok.Tok.startToken();
102       FormatTok.Tok.setKind(tok::eof);
103       EOFInitialized = true;
104     }
105     return &FormatTok;
106   }
107 
108   UnwrappedLine &Line;
109   FormatTokenSource *&TokenSource;
110   FormatToken *&ResetToken;
111   unsigned PreviousLineLevel;
112   FormatTokenSource *PreviousTokenSource;
113   bool &StructuralError;
114   bool PreviousStructuralError;
115 
116   FormatToken *Token;
117 };
118 
119 } // end anonymous namespace
120 
121 class ScopedLineState {
122 public:
123   ScopedLineState(UnwrappedLineParser &Parser,
124                   bool SwitchToPreprocessorLines = false)
125       : Parser(Parser), OriginalLines(Parser.CurrentLines) {
126     if (SwitchToPreprocessorLines)
127       Parser.CurrentLines = &Parser.PreprocessorDirectives;
128     else if (!Parser.Line->Tokens.empty())
129       Parser.CurrentLines = &Parser.Line->Tokens.back().Children;
130     PreBlockLine = std::move(Parser.Line);
131     Parser.Line = llvm::make_unique<UnwrappedLine>();
132     Parser.Line->Level = PreBlockLine->Level;
133     Parser.Line->InPPDirective = PreBlockLine->InPPDirective;
134   }
135 
136   ~ScopedLineState() {
137     if (!Parser.Line->Tokens.empty()) {
138       Parser.addUnwrappedLine();
139     }
140     assert(Parser.Line->Tokens.empty());
141     Parser.Line = std::move(PreBlockLine);
142     if (Parser.CurrentLines == &Parser.PreprocessorDirectives)
143       Parser.MustBreakBeforeNextToken = true;
144     Parser.CurrentLines = OriginalLines;
145   }
146 
147 private:
148   UnwrappedLineParser &Parser;
149 
150   std::unique_ptr<UnwrappedLine> PreBlockLine;
151   SmallVectorImpl<UnwrappedLine> *OriginalLines;
152 };
153 
154 class CompoundStatementIndenter {
155 public:
156   CompoundStatementIndenter(UnwrappedLineParser *Parser,
157                             const FormatStyle &Style, unsigned &LineLevel)
158       : LineLevel(LineLevel), OldLineLevel(LineLevel) {
159     if (Style.BreakBeforeBraces == FormatStyle::BS_Allman) {
160       Parser->addUnwrappedLine();
161     } else if (Style.BreakBeforeBraces == FormatStyle::BS_GNU) {
162       Parser->addUnwrappedLine();
163       ++LineLevel;
164     }
165   }
166   ~CompoundStatementIndenter() { LineLevel = OldLineLevel; }
167 
168 private:
169   unsigned &LineLevel;
170   unsigned OldLineLevel;
171 };
172 
173 namespace {
174 
175 class IndexedTokenSource : public FormatTokenSource {
176 public:
177   IndexedTokenSource(ArrayRef<FormatToken *> Tokens)
178       : Tokens(Tokens), Position(-1) {}
179 
180   FormatToken *getNextToken() override {
181     ++Position;
182     return Tokens[Position];
183   }
184 
185   unsigned getPosition() override {
186     assert(Position >= 0);
187     return Position;
188   }
189 
190   FormatToken *setPosition(unsigned P) override {
191     Position = P;
192     return Tokens[Position];
193   }
194 
195   void reset() { Position = -1; }
196 
197 private:
198   ArrayRef<FormatToken *> Tokens;
199   int Position;
200 };
201 
202 } // end anonymous namespace
203 
204 UnwrappedLineParser::UnwrappedLineParser(const FormatStyle &Style,
205                                          ArrayRef<FormatToken *> Tokens,
206                                          UnwrappedLineConsumer &Callback)
207     : Line(new UnwrappedLine), MustBreakBeforeNextToken(false),
208       CurrentLines(&Lines), StructuralError(false), Style(Style),
209       Tokens(nullptr), Callback(Callback), AllTokens(Tokens),
210       PPBranchLevel(-1) {}
211 
212 void UnwrappedLineParser::reset() {
213   PPBranchLevel = -1;
214   Line.reset(new UnwrappedLine);
215   CommentsBeforeNextToken.clear();
216   FormatTok = nullptr;
217   MustBreakBeforeNextToken = false;
218   PreprocessorDirectives.clear();
219   CurrentLines = &Lines;
220   DeclarationScopeStack.clear();
221   StructuralError = false;
222   PPStack.clear();
223 }
224 
225 bool UnwrappedLineParser::parse() {
226   IndexedTokenSource TokenSource(AllTokens);
227   do {
228     DEBUG(llvm::dbgs() << "----\n");
229     reset();
230     Tokens = &TokenSource;
231     TokenSource.reset();
232 
233     readToken();
234     parseFile();
235     // Create line with eof token.
236     pushToken(FormatTok);
237     addUnwrappedLine();
238 
239     for (SmallVectorImpl<UnwrappedLine>::iterator I = Lines.begin(),
240                                                   E = Lines.end();
241          I != E; ++I) {
242       Callback.consumeUnwrappedLine(*I);
243     }
244     Callback.finishRun();
245     Lines.clear();
246     while (!PPLevelBranchIndex.empty() &&
247            PPLevelBranchIndex.back() + 1 >= PPLevelBranchCount.back()) {
248       PPLevelBranchIndex.resize(PPLevelBranchIndex.size() - 1);
249       PPLevelBranchCount.resize(PPLevelBranchCount.size() - 1);
250     }
251     if (!PPLevelBranchIndex.empty()) {
252       ++PPLevelBranchIndex.back();
253       assert(PPLevelBranchIndex.size() == PPLevelBranchCount.size());
254       assert(PPLevelBranchIndex.back() <= PPLevelBranchCount.back());
255     }
256   } while (!PPLevelBranchIndex.empty());
257 
258   return StructuralError;
259 }
260 
261 void UnwrappedLineParser::parseFile() {
262   ScopedDeclarationState DeclarationState(
263       *Line, DeclarationScopeStack,
264       /*MustBeDeclaration=*/ !Line->InPPDirective);
265   parseLevel(/*HasOpeningBrace=*/false);
266   // Make sure to format the remaining tokens.
267   flushComments(true);
268   addUnwrappedLine();
269 }
270 
271 void UnwrappedLineParser::parseLevel(bool HasOpeningBrace) {
272   bool SwitchLabelEncountered = false;
273   do {
274     switch (FormatTok->Tok.getKind()) {
275     case tok::comment:
276       nextToken();
277       addUnwrappedLine();
278       break;
279     case tok::l_brace:
280       // FIXME: Add parameter whether this can happen - if this happens, we must
281       // be in a non-declaration context.
282       parseBlock(/*MustBeDeclaration=*/false);
283       addUnwrappedLine();
284       break;
285     case tok::r_brace:
286       if (HasOpeningBrace)
287         return;
288       StructuralError = true;
289       nextToken();
290       addUnwrappedLine();
291       break;
292     case tok::kw_default:
293     case tok::kw_case:
294       if (!SwitchLabelEncountered &&
295           (Style.IndentCaseLabels || (Line->InPPDirective && Line->Level == 1)))
296         ++Line->Level;
297       SwitchLabelEncountered = true;
298       parseStructuralElement();
299       break;
300     default:
301       parseStructuralElement();
302       break;
303     }
304   } while (!eof());
305 }
306 
307 void UnwrappedLineParser::calculateBraceTypes() {
308   // We'll parse forward through the tokens until we hit
309   // a closing brace or eof - note that getNextToken() will
310   // parse macros, so this will magically work inside macro
311   // definitions, too.
312   unsigned StoredPosition = Tokens->getPosition();
313   unsigned Position = StoredPosition;
314   FormatToken *Tok = FormatTok;
315   // Keep a stack of positions of lbrace tokens. We will
316   // update information about whether an lbrace starts a
317   // braced init list or a different block during the loop.
318   SmallVector<FormatToken *, 8> LBraceStack;
319   assert(Tok->Tok.is(tok::l_brace));
320   do {
321     // Get next none-comment token.
322     FormatToken *NextTok;
323     unsigned ReadTokens = 0;
324     do {
325       NextTok = Tokens->getNextToken();
326       ++ReadTokens;
327     } while (NextTok->is(tok::comment));
328 
329     switch (Tok->Tok.getKind()) {
330     case tok::l_brace:
331       LBraceStack.push_back(Tok);
332       break;
333     case tok::r_brace:
334       if (!LBraceStack.empty()) {
335         if (LBraceStack.back()->BlockKind == BK_Unknown) {
336           bool ProbablyBracedList = false;
337           if (Style.Language == FormatStyle::LK_Proto) {
338             ProbablyBracedList = NextTok->isOneOf(tok::comma, tok::r_square);
339           } else {
340             // Using OriginalColumn to distinguish between ObjC methods and
341             // binary operators is a bit hacky.
342             bool NextIsObjCMethod = NextTok->isOneOf(tok::plus, tok::minus) &&
343                                     NextTok->OriginalColumn == 0;
344 
345             // If there is a comma, semicolon or right paren after the closing
346             // brace, we assume this is a braced initializer list.  Note that
347             // regardless how we mark inner braces here, we will overwrite the
348             // BlockKind later if we parse a braced list (where all blocks
349             // inside are by default braced lists), or when we explicitly detect
350             // blocks (for example while parsing lambdas).
351             //
352             // We exclude + and - as they can be ObjC visibility modifiers.
353             ProbablyBracedList =
354                 NextTok->isOneOf(tok::comma, tok::semi, tok::period, tok::colon,
355                                  tok::r_paren, tok::r_square, tok::l_brace,
356                                  tok::l_paren, tok::ellipsis) ||
357                 (NextTok->isBinaryOperator() && !NextIsObjCMethod);
358           }
359           if (ProbablyBracedList) {
360             Tok->BlockKind = BK_BracedInit;
361             LBraceStack.back()->BlockKind = BK_BracedInit;
362           } else {
363             Tok->BlockKind = BK_Block;
364             LBraceStack.back()->BlockKind = BK_Block;
365           }
366         }
367         LBraceStack.pop_back();
368       }
369       break;
370     case tok::at:
371     case tok::semi:
372     case tok::kw_if:
373     case tok::kw_while:
374     case tok::kw_for:
375     case tok::kw_switch:
376     case tok::kw_try:
377       if (!LBraceStack.empty())
378         LBraceStack.back()->BlockKind = BK_Block;
379       break;
380     default:
381       break;
382     }
383     Tok = NextTok;
384     Position += ReadTokens;
385   } while (Tok->Tok.isNot(tok::eof) && !LBraceStack.empty());
386   // Assume other blocks for all unclosed opening braces.
387   for (unsigned i = 0, e = LBraceStack.size(); i != e; ++i) {
388     if (LBraceStack[i]->BlockKind == BK_Unknown)
389       LBraceStack[i]->BlockKind = BK_Block;
390   }
391 
392   FormatTok = Tokens->setPosition(StoredPosition);
393 }
394 
395 void UnwrappedLineParser::parseBlock(bool MustBeDeclaration, bool AddLevel,
396                                      bool MunchSemi) {
397   assert(FormatTok->Tok.is(tok::l_brace) && "'{' expected");
398   unsigned InitialLevel = Line->Level;
399   nextToken();
400 
401   addUnwrappedLine();
402 
403   ScopedDeclarationState DeclarationState(*Line, DeclarationScopeStack,
404                                           MustBeDeclaration);
405   if (AddLevel)
406     ++Line->Level;
407   parseLevel(/*HasOpeningBrace=*/true);
408 
409   if (!FormatTok->Tok.is(tok::r_brace)) {
410     Line->Level = InitialLevel;
411     StructuralError = true;
412     return;
413   }
414 
415   nextToken(); // Munch the closing brace.
416   if (MunchSemi && FormatTok->Tok.is(tok::semi))
417     nextToken();
418   Line->Level = InitialLevel;
419 }
420 
421 static bool IsGoogScope(const UnwrappedLine &Line) {
422   if (Line.Tokens.size() < 4)
423     return false;
424   auto I = Line.Tokens.begin();
425   if (I->Tok->TokenText != "goog")
426     return false;
427   ++I;
428   if (I->Tok->isNot(tok::period))
429     return false;
430   ++I;
431   if (I->Tok->TokenText != "scope")
432     return false;
433   ++I;
434   return I->Tok->is(tok::l_paren);
435 }
436 
437 static bool ShouldBreakBeforeBrace(const FormatStyle &Style,
438                                    const FormatToken &InitialToken) {
439   switch (Style.BreakBeforeBraces) {
440   case FormatStyle::BS_Linux:
441     return InitialToken.isOneOf(tok::kw_namespace, tok::kw_class);
442   case FormatStyle::BS_Allman:
443   case FormatStyle::BS_GNU:
444     return true;
445   default:
446     return false;
447   }
448 }
449 
450 void UnwrappedLineParser::parseChildBlock() {
451   FormatTok->BlockKind = BK_Block;
452   nextToken();
453   {
454     bool GoogScope =
455         Style.Language == FormatStyle::LK_JavaScript && IsGoogScope(*Line);
456     ScopedLineState LineState(*this);
457     ScopedDeclarationState DeclarationState(*Line, DeclarationScopeStack,
458                                             /*MustBeDeclaration=*/false);
459     Line->Level += GoogScope ? 0 : 1;
460     parseLevel(/*HasOpeningBrace=*/true);
461     Line->Level -= GoogScope ? 0 : 1;
462   }
463   nextToken();
464 }
465 
466 void UnwrappedLineParser::parsePPDirective() {
467   assert(FormatTok->Tok.is(tok::hash) && "'#' expected");
468   ScopedMacroState MacroState(*Line, Tokens, FormatTok, StructuralError);
469   nextToken();
470 
471   if (!FormatTok->Tok.getIdentifierInfo()) {
472     parsePPUnknown();
473     return;
474   }
475 
476   switch (FormatTok->Tok.getIdentifierInfo()->getPPKeywordID()) {
477   case tok::pp_define:
478     parsePPDefine();
479     return;
480   case tok::pp_if:
481     parsePPIf(/*IfDef=*/false);
482     break;
483   case tok::pp_ifdef:
484   case tok::pp_ifndef:
485     parsePPIf(/*IfDef=*/true);
486     break;
487   case tok::pp_else:
488     parsePPElse();
489     break;
490   case tok::pp_elif:
491     parsePPElIf();
492     break;
493   case tok::pp_endif:
494     parsePPEndIf();
495     break;
496   default:
497     parsePPUnknown();
498     break;
499   }
500 }
501 
502 void UnwrappedLineParser::conditionalCompilationCondition(bool Unreachable) {
503   if (Unreachable || (!PPStack.empty() && PPStack.back() == PP_Unreachable))
504     PPStack.push_back(PP_Unreachable);
505   else
506     PPStack.push_back(PP_Conditional);
507 }
508 
509 void UnwrappedLineParser::conditionalCompilationStart(bool Unreachable) {
510   ++PPBranchLevel;
511   assert(PPBranchLevel >= 0 && PPBranchLevel <= (int)PPLevelBranchIndex.size());
512   if (PPBranchLevel == (int)PPLevelBranchIndex.size()) {
513     PPLevelBranchIndex.push_back(0);
514     PPLevelBranchCount.push_back(0);
515   }
516   PPChainBranchIndex.push(0);
517   bool Skip = PPLevelBranchIndex[PPBranchLevel] > 0;
518   conditionalCompilationCondition(Unreachable || Skip);
519 }
520 
521 void UnwrappedLineParser::conditionalCompilationAlternative() {
522   if (!PPStack.empty())
523     PPStack.pop_back();
524   assert(PPBranchLevel < (int)PPLevelBranchIndex.size());
525   if (!PPChainBranchIndex.empty())
526     ++PPChainBranchIndex.top();
527   conditionalCompilationCondition(
528       PPBranchLevel >= 0 && !PPChainBranchIndex.empty() &&
529       PPLevelBranchIndex[PPBranchLevel] != PPChainBranchIndex.top());
530 }
531 
532 void UnwrappedLineParser::conditionalCompilationEnd() {
533   assert(PPBranchLevel < (int)PPLevelBranchIndex.size());
534   if (PPBranchLevel >= 0 && !PPChainBranchIndex.empty()) {
535     if (PPChainBranchIndex.top() + 1 > PPLevelBranchCount[PPBranchLevel]) {
536       PPLevelBranchCount[PPBranchLevel] = PPChainBranchIndex.top() + 1;
537     }
538   }
539   // Guard against #endif's without #if.
540   if (PPBranchLevel > 0)
541     --PPBranchLevel;
542   if (!PPChainBranchIndex.empty())
543     PPChainBranchIndex.pop();
544   if (!PPStack.empty())
545     PPStack.pop_back();
546 }
547 
548 void UnwrappedLineParser::parsePPIf(bool IfDef) {
549   nextToken();
550   bool IsLiteralFalse = (FormatTok->Tok.isLiteral() &&
551                          StringRef(FormatTok->Tok.getLiteralData(),
552                                    FormatTok->Tok.getLength()) == "0") ||
553                         FormatTok->Tok.is(tok::kw_false);
554   conditionalCompilationStart(!IfDef && IsLiteralFalse);
555   parsePPUnknown();
556 }
557 
558 void UnwrappedLineParser::parsePPElse() {
559   conditionalCompilationAlternative();
560   parsePPUnknown();
561 }
562 
563 void UnwrappedLineParser::parsePPElIf() { parsePPElse(); }
564 
565 void UnwrappedLineParser::parsePPEndIf() {
566   conditionalCompilationEnd();
567   parsePPUnknown();
568 }
569 
570 void UnwrappedLineParser::parsePPDefine() {
571   nextToken();
572 
573   if (FormatTok->Tok.getKind() != tok::identifier) {
574     parsePPUnknown();
575     return;
576   }
577   nextToken();
578   if (FormatTok->Tok.getKind() == tok::l_paren &&
579       FormatTok->WhitespaceRange.getBegin() ==
580           FormatTok->WhitespaceRange.getEnd()) {
581     parseParens();
582   }
583   addUnwrappedLine();
584   Line->Level = 1;
585 
586   // Errors during a preprocessor directive can only affect the layout of the
587   // preprocessor directive, and thus we ignore them. An alternative approach
588   // would be to use the same approach we use on the file level (no
589   // re-indentation if there was a structural error) within the macro
590   // definition.
591   parseFile();
592 }
593 
594 void UnwrappedLineParser::parsePPUnknown() {
595   do {
596     nextToken();
597   } while (!eof());
598   addUnwrappedLine();
599 }
600 
601 // Here we blacklist certain tokens that are not usually the first token in an
602 // unwrapped line. This is used in attempt to distinguish macro calls without
603 // trailing semicolons from other constructs split to several lines.
604 bool tokenCanStartNewLine(clang::Token Tok) {
605   // Semicolon can be a null-statement, l_square can be a start of a macro or
606   // a C++11 attribute, but this doesn't seem to be common.
607   return Tok.isNot(tok::semi) && Tok.isNot(tok::l_brace) &&
608          Tok.isNot(tok::l_square) &&
609          // Tokens that can only be used as binary operators and a part of
610          // overloaded operator names.
611          Tok.isNot(tok::period) && Tok.isNot(tok::periodstar) &&
612          Tok.isNot(tok::arrow) && Tok.isNot(tok::arrowstar) &&
613          Tok.isNot(tok::less) && Tok.isNot(tok::greater) &&
614          Tok.isNot(tok::slash) && Tok.isNot(tok::percent) &&
615          Tok.isNot(tok::lessless) && Tok.isNot(tok::greatergreater) &&
616          Tok.isNot(tok::equal) && Tok.isNot(tok::plusequal) &&
617          Tok.isNot(tok::minusequal) && Tok.isNot(tok::starequal) &&
618          Tok.isNot(tok::slashequal) && Tok.isNot(tok::percentequal) &&
619          Tok.isNot(tok::ampequal) && Tok.isNot(tok::pipeequal) &&
620          Tok.isNot(tok::caretequal) && Tok.isNot(tok::greatergreaterequal) &&
621          Tok.isNot(tok::lesslessequal) &&
622          // Colon is used in labels, base class lists, initializer lists,
623          // range-based for loops, ternary operator, but should never be the
624          // first token in an unwrapped line.
625          Tok.isNot(tok::colon) &&
626          // 'noexcept' is a trailing annotation.
627          Tok.isNot(tok::kw_noexcept);
628 }
629 
630 void UnwrappedLineParser::parseStructuralElement() {
631   assert(!FormatTok->Tok.is(tok::l_brace));
632   switch (FormatTok->Tok.getKind()) {
633   case tok::at:
634     nextToken();
635     if (FormatTok->Tok.is(tok::l_brace)) {
636       parseBracedList();
637       break;
638     }
639     switch (FormatTok->Tok.getObjCKeywordID()) {
640     case tok::objc_public:
641     case tok::objc_protected:
642     case tok::objc_package:
643     case tok::objc_private:
644       return parseAccessSpecifier();
645     case tok::objc_interface:
646     case tok::objc_implementation:
647       return parseObjCInterfaceOrImplementation();
648     case tok::objc_protocol:
649       return parseObjCProtocol();
650     case tok::objc_end:
651       return; // Handled by the caller.
652     case tok::objc_optional:
653     case tok::objc_required:
654       nextToken();
655       addUnwrappedLine();
656       return;
657     default:
658       break;
659     }
660     break;
661   case tok::kw_namespace:
662     parseNamespace();
663     return;
664   case tok::kw_inline:
665     nextToken();
666     if (FormatTok->Tok.is(tok::kw_namespace)) {
667       parseNamespace();
668       return;
669     }
670     break;
671   case tok::kw_public:
672   case tok::kw_protected:
673   case tok::kw_private:
674     parseAccessSpecifier();
675     return;
676   case tok::kw_if:
677     parseIfThenElse();
678     return;
679   case tok::kw_for:
680   case tok::kw_while:
681     parseForOrWhileLoop();
682     return;
683   case tok::kw_do:
684     parseDoWhile();
685     return;
686   case tok::kw_switch:
687     parseSwitch();
688     return;
689   case tok::kw_default:
690     nextToken();
691     parseLabel();
692     return;
693   case tok::kw_case:
694     parseCaseLabel();
695     return;
696   case tok::kw_try:
697     parseTryCatch();
698     return;
699   case tok::kw_extern:
700     nextToken();
701     if (FormatTok->Tok.is(tok::string_literal)) {
702       nextToken();
703       if (FormatTok->Tok.is(tok::l_brace)) {
704         parseBlock(/*MustBeDeclaration=*/true, /*AddLevel=*/false);
705         addUnwrappedLine();
706         return;
707       }
708     }
709     break;
710   case tok::identifier:
711     if (FormatTok->IsForEachMacro) {
712       parseForOrWhileLoop();
713       return;
714     }
715     // In all other cases, parse the declaration.
716     break;
717   default:
718     break;
719   }
720   do {
721     switch (FormatTok->Tok.getKind()) {
722     case tok::at:
723       nextToken();
724       if (FormatTok->Tok.is(tok::l_brace))
725         parseBracedList();
726       break;
727     case tok::kw_enum:
728       parseEnum();
729       break;
730     case tok::kw_typedef:
731       nextToken();
732       // FIXME: Use the IdentifierTable instead.
733       if (FormatTok->TokenText == "NS_ENUM")
734         parseEnum();
735       break;
736     case tok::kw_struct:
737     case tok::kw_union:
738     case tok::kw_class:
739       parseRecord();
740       // A record declaration or definition is always the start of a structural
741       // element.
742       break;
743     case tok::semi:
744       nextToken();
745       addUnwrappedLine();
746       return;
747     case tok::r_brace:
748       addUnwrappedLine();
749       return;
750     case tok::l_paren:
751       parseParens();
752       break;
753     case tok::caret:
754       nextToken();
755       if (FormatTok->Tok.isAnyIdentifier() ||
756           FormatTok->isSimpleTypeSpecifier())
757         nextToken();
758       if (FormatTok->is(tok::l_paren))
759         parseParens();
760       if (FormatTok->is(tok::l_brace))
761         parseChildBlock();
762       break;
763     case tok::l_brace:
764       if (!tryToParseBracedList()) {
765         // A block outside of parentheses must be the last part of a
766         // structural element.
767         // FIXME: Figure out cases where this is not true, and add projections
768         // for them (the one we know is missing are lambdas).
769         if (Style.BreakBeforeBraces != FormatStyle::BS_Attach)
770           addUnwrappedLine();
771         FormatTok->Type = TT_FunctionLBrace;
772         parseBlock(/*MustBeDeclaration=*/false);
773         addUnwrappedLine();
774         return;
775       }
776       // Otherwise this was a braced init list, and the structural
777       // element continues.
778       break;
779     case tok::kw_try:
780       // We arrive here when parsing function-try blocks.
781       parseTryCatch();
782       return;
783     case tok::identifier: {
784       StringRef Text = FormatTok->TokenText;
785       // Parse function literal unless 'function' is the first token in a line
786       // in which case this should be treated as a free-standing function.
787       if (Style.Language == FormatStyle::LK_JavaScript && Text == "function" &&
788           Line->Tokens.size() > 0) {
789         tryToParseJSFunction();
790         break;
791       }
792       nextToken();
793       if (Line->Tokens.size() == 1) {
794         if (FormatTok->Tok.is(tok::colon)) {
795           parseLabel();
796           return;
797         }
798         // Recognize function-like macro usages without trailing semicolon.
799         if (FormatTok->Tok.is(tok::l_paren)) {
800           parseParens();
801           if (FormatTok->NewlinesBefore > 0 &&
802               tokenCanStartNewLine(FormatTok->Tok) && Text == Text.upper()) {
803             addUnwrappedLine();
804             return;
805           }
806         } else if (FormatTok->HasUnescapedNewline && Text.size() >= 5 &&
807                    Text == Text.upper()) {
808           // Recognize free-standing macros like Q_OBJECT.
809           addUnwrappedLine();
810           return;
811         }
812       }
813       break;
814     }
815     case tok::equal:
816       nextToken();
817       if (FormatTok->Tok.is(tok::l_brace)) {
818         parseBracedList();
819       }
820       break;
821     case tok::l_square:
822       parseSquare();
823       break;
824     default:
825       nextToken();
826       break;
827     }
828   } while (!eof());
829 }
830 
831 bool UnwrappedLineParser::tryToParseLambda() {
832   // FIXME: This is a dirty way to access the previous token. Find a better
833   // solution.
834   if (!Line->Tokens.empty() &&
835       (Line->Tokens.back().Tok->isOneOf(tok::identifier, tok::kw_operator) ||
836        Line->Tokens.back().Tok->closesScope() ||
837        Line->Tokens.back().Tok->isSimpleTypeSpecifier())) {
838     nextToken();
839     return false;
840   }
841   assert(FormatTok->is(tok::l_square));
842   FormatToken &LSquare = *FormatTok;
843   if (!tryToParseLambdaIntroducer())
844     return false;
845 
846   while (FormatTok->isNot(tok::l_brace)) {
847     if (FormatTok->isSimpleTypeSpecifier()) {
848       nextToken();
849       continue;
850     }
851     switch (FormatTok->Tok.getKind()) {
852     case tok::l_brace:
853       break;
854     case tok::l_paren:
855       parseParens();
856       break;
857     case tok::less:
858     case tok::greater:
859     case tok::identifier:
860     case tok::coloncolon:
861     case tok::kw_mutable:
862       nextToken();
863       break;
864     case tok::arrow:
865       FormatTok->Type = TT_TrailingReturnArrow;
866       nextToken();
867       break;
868     default:
869       return true;
870     }
871   }
872   LSquare.Type = TT_LambdaLSquare;
873   parseChildBlock();
874   return true;
875 }
876 
877 bool UnwrappedLineParser::tryToParseLambdaIntroducer() {
878   nextToken();
879   if (FormatTok->is(tok::equal)) {
880     nextToken();
881     if (FormatTok->is(tok::r_square)) {
882       nextToken();
883       return true;
884     }
885     if (FormatTok->isNot(tok::comma))
886       return false;
887     nextToken();
888   } else if (FormatTok->is(tok::amp)) {
889     nextToken();
890     if (FormatTok->is(tok::r_square)) {
891       nextToken();
892       return true;
893     }
894     if (!FormatTok->isOneOf(tok::comma, tok::identifier)) {
895       return false;
896     }
897     if (FormatTok->is(tok::comma))
898       nextToken();
899   } else if (FormatTok->is(tok::r_square)) {
900     nextToken();
901     return true;
902   }
903   do {
904     if (FormatTok->is(tok::amp))
905       nextToken();
906     if (!FormatTok->isOneOf(tok::identifier, tok::kw_this))
907       return false;
908     nextToken();
909     if (FormatTok->is(tok::ellipsis))
910       nextToken();
911     if (FormatTok->is(tok::comma)) {
912       nextToken();
913     } else if (FormatTok->is(tok::r_square)) {
914       nextToken();
915       return true;
916     } else {
917       return false;
918     }
919   } while (!eof());
920   return false;
921 }
922 
923 void UnwrappedLineParser::tryToParseJSFunction() {
924   nextToken();
925 
926   // Consume function name.
927   if (FormatTok->is(tok::identifier))
928       nextToken();
929 
930   if (FormatTok->isNot(tok::l_paren))
931     return;
932   nextToken();
933   while (FormatTok->isNot(tok::l_brace)) {
934     // Err on the side of caution in order to avoid consuming the full file in
935     // case of incomplete code.
936     if (!FormatTok->isOneOf(tok::identifier, tok::comma, tok::r_paren,
937                             tok::comment))
938       return;
939     nextToken();
940   }
941   parseChildBlock();
942 }
943 
944 bool UnwrappedLineParser::tryToParseBracedList() {
945   if (FormatTok->BlockKind == BK_Unknown)
946     calculateBraceTypes();
947   assert(FormatTok->BlockKind != BK_Unknown);
948   if (FormatTok->BlockKind == BK_Block)
949     return false;
950   parseBracedList();
951   return true;
952 }
953 
954 bool UnwrappedLineParser::parseBracedList(bool ContinueOnSemicolons) {
955   bool HasError = false;
956   nextToken();
957 
958   // FIXME: Once we have an expression parser in the UnwrappedLineParser,
959   // replace this by using parseAssigmentExpression() inside.
960   do {
961     if (Style.Language == FormatStyle::LK_JavaScript &&
962         FormatTok->TokenText == "function") {
963       tryToParseJSFunction();
964       continue;
965     }
966     switch (FormatTok->Tok.getKind()) {
967     case tok::caret:
968       nextToken();
969       if (FormatTok->is(tok::l_brace)) {
970         parseChildBlock();
971       }
972       break;
973     case tok::l_square:
974       tryToParseLambda();
975       break;
976     case tok::l_brace:
977       // Assume there are no blocks inside a braced init list apart
978       // from the ones we explicitly parse out (like lambdas).
979       FormatTok->BlockKind = BK_BracedInit;
980       parseBracedList();
981       break;
982     case tok::r_brace:
983       nextToken();
984       return !HasError;
985     case tok::semi:
986       HasError = true;
987       if (!ContinueOnSemicolons)
988         return !HasError;
989       nextToken();
990       break;
991     case tok::comma:
992       nextToken();
993       break;
994     default:
995       nextToken();
996       break;
997     }
998   } while (!eof());
999   return false;
1000 }
1001 
1002 void UnwrappedLineParser::parseParens() {
1003   assert(FormatTok->Tok.is(tok::l_paren) && "'(' expected.");
1004   nextToken();
1005   do {
1006     switch (FormatTok->Tok.getKind()) {
1007     case tok::l_paren:
1008       parseParens();
1009       break;
1010     case tok::r_paren:
1011       nextToken();
1012       return;
1013     case tok::r_brace:
1014       // A "}" inside parenthesis is an error if there wasn't a matching "{".
1015       return;
1016     case tok::l_square:
1017       tryToParseLambda();
1018       break;
1019     case tok::l_brace: {
1020       if (!tryToParseBracedList()) {
1021         parseChildBlock();
1022       }
1023       break;
1024     }
1025     case tok::at:
1026       nextToken();
1027       if (FormatTok->Tok.is(tok::l_brace))
1028         parseBracedList();
1029       break;
1030     default:
1031       nextToken();
1032       break;
1033     }
1034   } while (!eof());
1035 }
1036 
1037 void UnwrappedLineParser::parseSquare() {
1038   assert(FormatTok->Tok.is(tok::l_square) && "'[' expected.");
1039   if (tryToParseLambda())
1040     return;
1041   do {
1042     switch (FormatTok->Tok.getKind()) {
1043     case tok::l_paren:
1044       parseParens();
1045       break;
1046     case tok::r_square:
1047       nextToken();
1048       return;
1049     case tok::r_brace:
1050       // A "}" inside parenthesis is an error if there wasn't a matching "{".
1051       return;
1052     case tok::l_square:
1053       parseSquare();
1054       break;
1055     case tok::l_brace: {
1056       if (!tryToParseBracedList()) {
1057         parseChildBlock();
1058       }
1059       break;
1060     }
1061     case tok::at:
1062       nextToken();
1063       if (FormatTok->Tok.is(tok::l_brace))
1064         parseBracedList();
1065       break;
1066     default:
1067       nextToken();
1068       break;
1069     }
1070   } while (!eof());
1071 }
1072 
1073 void UnwrappedLineParser::parseIfThenElse() {
1074   assert(FormatTok->Tok.is(tok::kw_if) && "'if' expected");
1075   nextToken();
1076   if (FormatTok->Tok.is(tok::l_paren))
1077     parseParens();
1078   bool NeedsUnwrappedLine = false;
1079   if (FormatTok->Tok.is(tok::l_brace)) {
1080     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1081     parseBlock(/*MustBeDeclaration=*/false);
1082     if (Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
1083         Style.BreakBeforeBraces == FormatStyle::BS_GNU) {
1084       addUnwrappedLine();
1085     } else {
1086       NeedsUnwrappedLine = true;
1087     }
1088   } else {
1089     addUnwrappedLine();
1090     ++Line->Level;
1091     parseStructuralElement();
1092     --Line->Level;
1093   }
1094   if (FormatTok->Tok.is(tok::kw_else)) {
1095     if (Style.BreakBeforeBraces == FormatStyle::BS_Stroustrup)
1096       addUnwrappedLine();
1097     nextToken();
1098     if (FormatTok->Tok.is(tok::l_brace)) {
1099       CompoundStatementIndenter Indenter(this, Style, Line->Level);
1100       parseBlock(/*MustBeDeclaration=*/false);
1101       addUnwrappedLine();
1102     } else if (FormatTok->Tok.is(tok::kw_if)) {
1103       parseIfThenElse();
1104     } else {
1105       addUnwrappedLine();
1106       ++Line->Level;
1107       parseStructuralElement();
1108       --Line->Level;
1109     }
1110   } else if (NeedsUnwrappedLine) {
1111     addUnwrappedLine();
1112   }
1113 }
1114 
1115 void UnwrappedLineParser::parseTryCatch() {
1116   assert(FormatTok->is(tok::kw_try) && "'try' expected");
1117   nextToken();
1118   bool NeedsUnwrappedLine = false;
1119   if (FormatTok->is(tok::colon)) {
1120     // We are in a function try block, what comes is an initializer list.
1121     nextToken();
1122     while (FormatTok->is(tok::identifier)) {
1123       nextToken();
1124       if (FormatTok->is(tok::l_paren))
1125         parseParens();
1126       else
1127         StructuralError = true;
1128       if (FormatTok->is(tok::comma))
1129         nextToken();
1130     }
1131   }
1132   if (FormatTok->is(tok::l_brace)) {
1133     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1134     parseBlock(/*MustBeDeclaration=*/false);
1135     if (Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
1136         Style.BreakBeforeBraces == FormatStyle::BS_GNU ||
1137         Style.BreakBeforeBraces == FormatStyle::BS_Stroustrup) {
1138       addUnwrappedLine();
1139     } else {
1140       NeedsUnwrappedLine = true;
1141     }
1142   } else if (!FormatTok->is(tok::kw_catch)) {
1143     // The C++ standard requires a compound-statement after a try.
1144     // If there's none, we try to assume there's a structuralElement
1145     // and try to continue.
1146     StructuralError = true;
1147     addUnwrappedLine();
1148     ++Line->Level;
1149     parseStructuralElement();
1150     --Line->Level;
1151   }
1152   while (FormatTok->is(tok::kw_catch) ||
1153          (Style.Language == FormatStyle::LK_JavaScript &&
1154           FormatTok->TokenText == "finally")) {
1155     nextToken();
1156     while (FormatTok->isNot(tok::l_brace)) {
1157       if (FormatTok->is(tok::l_paren)) {
1158         parseParens();
1159         continue;
1160       }
1161       if (FormatTok->isOneOf(tok::semi, tok::r_brace))
1162         return;
1163       nextToken();
1164     }
1165     NeedsUnwrappedLine = false;
1166     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1167     parseBlock(/*MustBeDeclaration=*/false);
1168     if (Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
1169         Style.BreakBeforeBraces == FormatStyle::BS_GNU ||
1170         Style.BreakBeforeBraces == FormatStyle::BS_Stroustrup) {
1171       addUnwrappedLine();
1172     } else {
1173       NeedsUnwrappedLine = true;
1174     }
1175   }
1176   if (NeedsUnwrappedLine) {
1177     addUnwrappedLine();
1178   }
1179 }
1180 
1181 void UnwrappedLineParser::parseNamespace() {
1182   assert(FormatTok->Tok.is(tok::kw_namespace) && "'namespace' expected");
1183 
1184   const FormatToken &InitialToken = *FormatTok;
1185   nextToken();
1186   if (FormatTok->Tok.is(tok::identifier))
1187     nextToken();
1188   if (FormatTok->Tok.is(tok::l_brace)) {
1189     if (ShouldBreakBeforeBrace(Style, InitialToken))
1190       addUnwrappedLine();
1191 
1192     bool AddLevel = Style.NamespaceIndentation == FormatStyle::NI_All ||
1193                     (Style.NamespaceIndentation == FormatStyle::NI_Inner &&
1194                      DeclarationScopeStack.size() > 1);
1195     parseBlock(/*MustBeDeclaration=*/true, AddLevel);
1196     // Munch the semicolon after a namespace. This is more common than one would
1197     // think. Puttin the semicolon into its own line is very ugly.
1198     if (FormatTok->Tok.is(tok::semi))
1199       nextToken();
1200     addUnwrappedLine();
1201   }
1202   // FIXME: Add error handling.
1203 }
1204 
1205 void UnwrappedLineParser::parseForOrWhileLoop() {
1206   assert((FormatTok->Tok.is(tok::kw_for) || FormatTok->Tok.is(tok::kw_while) ||
1207           FormatTok->IsForEachMacro) &&
1208          "'for', 'while' or foreach macro expected");
1209   nextToken();
1210   if (FormatTok->Tok.is(tok::l_paren))
1211     parseParens();
1212   if (FormatTok->Tok.is(tok::l_brace)) {
1213     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1214     parseBlock(/*MustBeDeclaration=*/false);
1215     addUnwrappedLine();
1216   } else {
1217     addUnwrappedLine();
1218     ++Line->Level;
1219     parseStructuralElement();
1220     --Line->Level;
1221   }
1222 }
1223 
1224 void UnwrappedLineParser::parseDoWhile() {
1225   assert(FormatTok->Tok.is(tok::kw_do) && "'do' expected");
1226   nextToken();
1227   if (FormatTok->Tok.is(tok::l_brace)) {
1228     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1229     parseBlock(/*MustBeDeclaration=*/false);
1230     if (Style.BreakBeforeBraces == FormatStyle::BS_GNU)
1231       addUnwrappedLine();
1232   } else {
1233     addUnwrappedLine();
1234     ++Line->Level;
1235     parseStructuralElement();
1236     --Line->Level;
1237   }
1238 
1239   // FIXME: Add error handling.
1240   if (!FormatTok->Tok.is(tok::kw_while)) {
1241     addUnwrappedLine();
1242     return;
1243   }
1244 
1245   nextToken();
1246   parseStructuralElement();
1247 }
1248 
1249 void UnwrappedLineParser::parseLabel() {
1250   nextToken();
1251   unsigned OldLineLevel = Line->Level;
1252   if (Line->Level > 1 || (!Line->InPPDirective && Line->Level > 0))
1253     --Line->Level;
1254   if (CommentsBeforeNextToken.empty() && FormatTok->Tok.is(tok::l_brace)) {
1255     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1256     parseBlock(/*MustBeDeclaration=*/false);
1257     if (FormatTok->Tok.is(tok::kw_break)) {
1258       // "break;" after "}" on its own line only for BS_Allman and BS_GNU
1259       if (Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
1260           Style.BreakBeforeBraces == FormatStyle::BS_GNU) {
1261         addUnwrappedLine();
1262       }
1263       parseStructuralElement();
1264     }
1265     addUnwrappedLine();
1266   } else {
1267     addUnwrappedLine();
1268   }
1269   Line->Level = OldLineLevel;
1270 }
1271 
1272 void UnwrappedLineParser::parseCaseLabel() {
1273   assert(FormatTok->Tok.is(tok::kw_case) && "'case' expected");
1274   // FIXME: fix handling of complex expressions here.
1275   do {
1276     nextToken();
1277   } while (!eof() && !FormatTok->Tok.is(tok::colon));
1278   parseLabel();
1279 }
1280 
1281 void UnwrappedLineParser::parseSwitch() {
1282   assert(FormatTok->Tok.is(tok::kw_switch) && "'switch' expected");
1283   nextToken();
1284   if (FormatTok->Tok.is(tok::l_paren))
1285     parseParens();
1286   if (FormatTok->Tok.is(tok::l_brace)) {
1287     CompoundStatementIndenter Indenter(this, Style, Line->Level);
1288     parseBlock(/*MustBeDeclaration=*/false);
1289     addUnwrappedLine();
1290   } else {
1291     addUnwrappedLine();
1292     ++Line->Level;
1293     parseStructuralElement();
1294     --Line->Level;
1295   }
1296 }
1297 
1298 void UnwrappedLineParser::parseAccessSpecifier() {
1299   nextToken();
1300   // Understand Qt's slots.
1301   if (FormatTok->is(tok::identifier) &&
1302       (FormatTok->TokenText == "slots" || FormatTok->TokenText == "Q_SLOTS"))
1303     nextToken();
1304   // Otherwise, we don't know what it is, and we'd better keep the next token.
1305   if (FormatTok->Tok.is(tok::colon))
1306     nextToken();
1307   addUnwrappedLine();
1308 }
1309 
1310 void UnwrappedLineParser::parseEnum() {
1311   if (FormatTok->Tok.is(tok::kw_enum)) {
1312     // Won't be 'enum' for NS_ENUMs.
1313     nextToken();
1314   }
1315   // Eat up enum class ...
1316   if (FormatTok->Tok.is(tok::kw_class) || FormatTok->Tok.is(tok::kw_struct))
1317     nextToken();
1318   while (FormatTok->Tok.getIdentifierInfo() ||
1319          FormatTok->isOneOf(tok::colon, tok::coloncolon)) {
1320     nextToken();
1321     // We can have macros or attributes in between 'enum' and the enum name.
1322     if (FormatTok->Tok.is(tok::l_paren)) {
1323       parseParens();
1324     }
1325     if (FormatTok->Tok.is(tok::identifier))
1326       nextToken();
1327   }
1328   if (FormatTok->Tok.is(tok::l_brace)) {
1329     FormatTok->BlockKind = BK_Block;
1330     bool HasError = !parseBracedList(/*ContinueOnSemicolons=*/true);
1331     if (HasError) {
1332       if (FormatTok->is(tok::semi))
1333         nextToken();
1334       addUnwrappedLine();
1335     }
1336   }
1337   // We fall through to parsing a structural element afterwards, so that in
1338   // enum A {} n, m;
1339   // "} n, m;" will end up in one unwrapped line.
1340 }
1341 
1342 void UnwrappedLineParser::parseRecord() {
1343   const FormatToken &InitialToken = *FormatTok;
1344   nextToken();
1345   if (FormatTok->isOneOf(tok::identifier, tok::coloncolon, tok::kw___attribute,
1346                          tok::kw___declspec, tok::kw_alignas)) {
1347     nextToken();
1348     // We can have macros or attributes in between 'class' and the class name.
1349     if (FormatTok->Tok.is(tok::l_paren)) {
1350       parseParens();
1351     }
1352     // The actual identifier can be a nested name specifier, and in macros
1353     // it is often token-pasted.
1354     while (FormatTok->Tok.is(tok::identifier) ||
1355            FormatTok->Tok.is(tok::coloncolon) ||
1356            FormatTok->Tok.is(tok::hashhash))
1357       nextToken();
1358 
1359     // Note that parsing away template declarations here leads to incorrectly
1360     // accepting function declarations as record declarations.
1361     // In general, we cannot solve this problem. Consider:
1362     // class A<int> B() {}
1363     // which can be a function definition or a class definition when B() is a
1364     // macro. If we find enough real-world cases where this is a problem, we
1365     // can parse for the 'template' keyword in the beginning of the statement,
1366     // and thus rule out the record production in case there is no template
1367     // (this would still leave us with an ambiguity between template function
1368     // and class declarations).
1369     if (FormatTok->Tok.is(tok::colon) || FormatTok->Tok.is(tok::less)) {
1370       while (!eof() && FormatTok->Tok.isNot(tok::l_brace)) {
1371         if (FormatTok->Tok.is(tok::semi))
1372           return;
1373         nextToken();
1374       }
1375     }
1376   }
1377   if (FormatTok->Tok.is(tok::l_brace)) {
1378     if (ShouldBreakBeforeBrace(Style, InitialToken))
1379       addUnwrappedLine();
1380 
1381     parseBlock(/*MustBeDeclaration=*/true, /*AddLevel=*/true,
1382                /*MunchSemi=*/false);
1383   }
1384   // We fall through to parsing a structural element afterwards, so
1385   // class A {} n, m;
1386   // will end up in one unwrapped line.
1387 }
1388 
1389 void UnwrappedLineParser::parseObjCProtocolList() {
1390   assert(FormatTok->Tok.is(tok::less) && "'<' expected.");
1391   do
1392     nextToken();
1393   while (!eof() && FormatTok->Tok.isNot(tok::greater));
1394   nextToken(); // Skip '>'.
1395 }
1396 
1397 void UnwrappedLineParser::parseObjCUntilAtEnd() {
1398   do {
1399     if (FormatTok->Tok.isObjCAtKeyword(tok::objc_end)) {
1400       nextToken();
1401       addUnwrappedLine();
1402       break;
1403     }
1404     if (FormatTok->is(tok::l_brace)) {
1405       parseBlock(/*MustBeDeclaration=*/false);
1406       // In ObjC interfaces, nothing should be following the "}".
1407       addUnwrappedLine();
1408     } else if (FormatTok->is(tok::r_brace)) {
1409       // Ignore stray "}". parseStructuralElement doesn't consume them.
1410       nextToken();
1411       addUnwrappedLine();
1412     } else {
1413       parseStructuralElement();
1414     }
1415   } while (!eof());
1416 }
1417 
1418 void UnwrappedLineParser::parseObjCInterfaceOrImplementation() {
1419   nextToken();
1420   nextToken(); // interface name
1421 
1422   // @interface can be followed by either a base class, or a category.
1423   if (FormatTok->Tok.is(tok::colon)) {
1424     nextToken();
1425     nextToken(); // base class name
1426   } else if (FormatTok->Tok.is(tok::l_paren))
1427     // Skip category, if present.
1428     parseParens();
1429 
1430   if (FormatTok->Tok.is(tok::less))
1431     parseObjCProtocolList();
1432 
1433   if (FormatTok->Tok.is(tok::l_brace)) {
1434     if (Style.BreakBeforeBraces == FormatStyle::BS_Allman ||
1435         Style.BreakBeforeBraces == FormatStyle::BS_GNU)
1436       addUnwrappedLine();
1437     parseBlock(/*MustBeDeclaration=*/true);
1438   }
1439 
1440   // With instance variables, this puts '}' on its own line.  Without instance
1441   // variables, this ends the @interface line.
1442   addUnwrappedLine();
1443 
1444   parseObjCUntilAtEnd();
1445 }
1446 
1447 void UnwrappedLineParser::parseObjCProtocol() {
1448   nextToken();
1449   nextToken(); // protocol name
1450 
1451   if (FormatTok->Tok.is(tok::less))
1452     parseObjCProtocolList();
1453 
1454   // Check for protocol declaration.
1455   if (FormatTok->Tok.is(tok::semi)) {
1456     nextToken();
1457     return addUnwrappedLine();
1458   }
1459 
1460   addUnwrappedLine();
1461   parseObjCUntilAtEnd();
1462 }
1463 
1464 LLVM_ATTRIBUTE_UNUSED static void printDebugInfo(const UnwrappedLine &Line,
1465                                                  StringRef Prefix = "") {
1466   llvm::dbgs() << Prefix << "Line(" << Line.Level << ")"
1467                << (Line.InPPDirective ? " MACRO" : "") << ": ";
1468   for (std::list<UnwrappedLineNode>::const_iterator I = Line.Tokens.begin(),
1469                                                     E = Line.Tokens.end();
1470        I != E; ++I) {
1471     llvm::dbgs() << I->Tok->Tok.getName() << "[" << I->Tok->Type << "] ";
1472   }
1473   for (std::list<UnwrappedLineNode>::const_iterator I = Line.Tokens.begin(),
1474                                                     E = Line.Tokens.end();
1475        I != E; ++I) {
1476     const UnwrappedLineNode &Node = *I;
1477     for (SmallVectorImpl<UnwrappedLine>::const_iterator
1478              I = Node.Children.begin(),
1479              E = Node.Children.end();
1480          I != E; ++I) {
1481       printDebugInfo(*I, "\nChild: ");
1482     }
1483   }
1484   llvm::dbgs() << "\n";
1485 }
1486 
1487 void UnwrappedLineParser::addUnwrappedLine() {
1488   if (Line->Tokens.empty())
1489     return;
1490   DEBUG({
1491     if (CurrentLines == &Lines)
1492       printDebugInfo(*Line);
1493   });
1494   CurrentLines->push_back(*Line);
1495   Line->Tokens.clear();
1496   if (CurrentLines == &Lines && !PreprocessorDirectives.empty()) {
1497     for (SmallVectorImpl<UnwrappedLine>::iterator
1498              I = PreprocessorDirectives.begin(),
1499              E = PreprocessorDirectives.end();
1500          I != E; ++I) {
1501       CurrentLines->push_back(*I);
1502     }
1503     PreprocessorDirectives.clear();
1504   }
1505 }
1506 
1507 bool UnwrappedLineParser::eof() const { return FormatTok->Tok.is(tok::eof); }
1508 
1509 bool UnwrappedLineParser::isOnNewLine(const FormatToken &FormatTok) {
1510   return (Line->InPPDirective || FormatTok.HasUnescapedNewline) &&
1511          FormatTok.NewlinesBefore > 0;
1512 }
1513 
1514 void UnwrappedLineParser::flushComments(bool NewlineBeforeNext) {
1515   bool JustComments = Line->Tokens.empty();
1516   for (SmallVectorImpl<FormatToken *>::const_iterator
1517            I = CommentsBeforeNextToken.begin(),
1518            E = CommentsBeforeNextToken.end();
1519        I != E; ++I) {
1520     if (isOnNewLine(**I) && JustComments) {
1521       addUnwrappedLine();
1522     }
1523     pushToken(*I);
1524   }
1525   if (NewlineBeforeNext && JustComments) {
1526     addUnwrappedLine();
1527   }
1528   CommentsBeforeNextToken.clear();
1529 }
1530 
1531 void UnwrappedLineParser::nextToken() {
1532   if (eof())
1533     return;
1534   flushComments(isOnNewLine(*FormatTok));
1535   pushToken(FormatTok);
1536   readToken();
1537 }
1538 
1539 void UnwrappedLineParser::readToken() {
1540   bool CommentsInCurrentLine = true;
1541   do {
1542     FormatTok = Tokens->getNextToken();
1543     assert(FormatTok);
1544     while (!Line->InPPDirective && FormatTok->Tok.is(tok::hash) &&
1545            (FormatTok->HasUnescapedNewline || FormatTok->IsFirst)) {
1546       // If there is an unfinished unwrapped line, we flush the preprocessor
1547       // directives only after that unwrapped line was finished later.
1548       bool SwitchToPreprocessorLines =
1549           !Line->Tokens.empty() && CurrentLines == &Lines;
1550       ScopedLineState BlockState(*this, SwitchToPreprocessorLines);
1551       // Comments stored before the preprocessor directive need to be output
1552       // before the preprocessor directive, at the same level as the
1553       // preprocessor directive, as we consider them to apply to the directive.
1554       flushComments(isOnNewLine(*FormatTok));
1555       parsePPDirective();
1556     }
1557     while (FormatTok->Type == TT_ConflictStart ||
1558            FormatTok->Type == TT_ConflictEnd ||
1559            FormatTok->Type == TT_ConflictAlternative) {
1560       if (FormatTok->Type == TT_ConflictStart) {
1561         conditionalCompilationStart(/*Unreachable=*/false);
1562       } else if (FormatTok->Type == TT_ConflictAlternative) {
1563         conditionalCompilationAlternative();
1564       } else if (FormatTok->Type == TT_ConflictEnd) {
1565         conditionalCompilationEnd();
1566       }
1567       FormatTok = Tokens->getNextToken();
1568       FormatTok->MustBreakBefore = true;
1569     }
1570 
1571     if (!PPStack.empty() && (PPStack.back() == PP_Unreachable) &&
1572         !Line->InPPDirective) {
1573       continue;
1574     }
1575 
1576     if (!FormatTok->Tok.is(tok::comment))
1577       return;
1578     if (isOnNewLine(*FormatTok) || FormatTok->IsFirst) {
1579       CommentsInCurrentLine = false;
1580     }
1581     if (CommentsInCurrentLine) {
1582       pushToken(FormatTok);
1583     } else {
1584       CommentsBeforeNextToken.push_back(FormatTok);
1585     }
1586   } while (!eof());
1587 }
1588 
1589 void UnwrappedLineParser::pushToken(FormatToken *Tok) {
1590   Line->Tokens.push_back(UnwrappedLineNode(Tok));
1591   if (MustBreakBeforeNextToken) {
1592     Line->Tokens.back().Tok->MustBreakBefore = true;
1593     MustBreakBeforeNextToken = false;
1594   }
1595 }
1596 
1597 } // end namespace format
1598 } // end namespace clang
1599