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