1 //===--- TokenAnnotator.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 implements a token annotator, i.e. creates
12 /// \c AnnotatedTokens out of \c FormatTokens with required extra information.
13 ///
14 //===----------------------------------------------------------------------===//
15
16 #include "TokenAnnotator.h"
17 #include "clang/Basic/SourceManager.h"
18 #include "llvm/ADT/SmallPtrSet.h"
19 #include "llvm/Support/Debug.h"
20
21 #define DEBUG_TYPE "format-token-annotator"
22
23 namespace clang {
24 namespace format {
25
26 namespace {
27
28 /// \brief A parser that gathers additional information about tokens.
29 ///
30 /// The \c TokenAnnotator tries to match parenthesis and square brakets and
31 /// store a parenthesis levels. It also tries to resolve matching "<" and ">"
32 /// into template parameter lists.
33 class AnnotatingParser {
34 public:
AnnotatingParser(const FormatStyle & Style,AnnotatedLine & Line,const AdditionalKeywords & Keywords)35 AnnotatingParser(const FormatStyle &Style, AnnotatedLine &Line,
36 const AdditionalKeywords &Keywords)
37 : Style(Style), Line(Line), CurrentToken(Line.First), AutoFound(false),
38 Keywords(Keywords) {
39 Contexts.push_back(Context(tok::unknown, 1, /*IsExpression=*/false));
40 resetTokenMetadata(CurrentToken);
41 }
42
43 private:
parseAngle()44 bool parseAngle() {
45 if (!CurrentToken)
46 return false;
47 FormatToken *Left = CurrentToken->Previous;
48 Left->ParentBracket = Contexts.back().ContextKind;
49 ScopedContextCreator ContextCreator(*this, tok::less, 10);
50
51 // If this angle is in the context of an expression, we need to be more
52 // hesitant to detect it as opening template parameters.
53 bool InExprContext = Contexts.back().IsExpression;
54
55 Contexts.back().IsExpression = false;
56 // If there's a template keyword before the opening angle bracket, this is a
57 // template parameter, not an argument.
58 Contexts.back().InTemplateArgument =
59 Left->Previous && Left->Previous->Tok.isNot(tok::kw_template);
60
61 if (Style.Language == FormatStyle::LK_Java &&
62 CurrentToken->is(tok::question))
63 next();
64
65 while (CurrentToken) {
66 if (CurrentToken->is(tok::greater)) {
67 Left->MatchingParen = CurrentToken;
68 CurrentToken->MatchingParen = Left;
69 CurrentToken->Type = TT_TemplateCloser;
70 next();
71 return true;
72 }
73 if (CurrentToken->is(tok::question) &&
74 Style.Language == FormatStyle::LK_Java) {
75 next();
76 continue;
77 }
78 if (CurrentToken->isOneOf(tok::r_paren, tok::r_square, tok::r_brace) ||
79 (CurrentToken->isOneOf(tok::colon, tok::question) && InExprContext))
80 return false;
81 // If a && or || is found and interpreted as a binary operator, this set
82 // of angles is likely part of something like "a < b && c > d". If the
83 // angles are inside an expression, the ||/&& might also be a binary
84 // operator that was misinterpreted because we are parsing template
85 // parameters.
86 // FIXME: This is getting out of hand, write a decent parser.
87 if (CurrentToken->Previous->isOneOf(tok::pipepipe, tok::ampamp) &&
88 CurrentToken->Previous->is(TT_BinaryOperator) &&
89 Contexts[Contexts.size() - 2].IsExpression &&
90 !Line.startsWith(tok::kw_template))
91 return false;
92 updateParameterCount(Left, CurrentToken);
93 if (!consumeToken())
94 return false;
95 }
96 return false;
97 }
98
parseParens(bool LookForDecls=false)99 bool parseParens(bool LookForDecls = false) {
100 if (!CurrentToken)
101 return false;
102 FormatToken *Left = CurrentToken->Previous;
103 Left->ParentBracket = Contexts.back().ContextKind;
104 ScopedContextCreator ContextCreator(*this, tok::l_paren, 1);
105
106 // FIXME: This is a bit of a hack. Do better.
107 Contexts.back().ColonIsForRangeExpr =
108 Contexts.size() == 2 && Contexts[0].ColonIsForRangeExpr;
109
110 bool StartsObjCMethodExpr = false;
111 if (CurrentToken->is(tok::caret)) {
112 // (^ can start a block type.
113 Left->Type = TT_ObjCBlockLParen;
114 } else if (FormatToken *MaybeSel = Left->Previous) {
115 // @selector( starts a selector.
116 if (MaybeSel->isObjCAtKeyword(tok::objc_selector) && MaybeSel->Previous &&
117 MaybeSel->Previous->is(tok::at)) {
118 StartsObjCMethodExpr = true;
119 }
120 }
121
122 if (Left->Previous &&
123 (Left->Previous->isOneOf(tok::kw_static_assert, tok::kw_decltype,
124 tok::kw_if, tok::kw_while, tok::l_paren,
125 tok::comma) ||
126 Left->Previous->is(TT_BinaryOperator))) {
127 // static_assert, if and while usually contain expressions.
128 Contexts.back().IsExpression = true;
129 } else if (Left->Previous && Left->Previous->is(tok::r_square) &&
130 Left->Previous->MatchingParen &&
131 Left->Previous->MatchingParen->is(TT_LambdaLSquare)) {
132 // This is a parameter list of a lambda expression.
133 Contexts.back().IsExpression = false;
134 } else if (Line.InPPDirective &&
135 (!Left->Previous ||
136 !Left->Previous->isOneOf(tok::identifier,
137 TT_OverloadedOperator))) {
138 Contexts.back().IsExpression = true;
139 } else if (Contexts[Contexts.size() - 2].CaretFound) {
140 // This is the parameter list of an ObjC block.
141 Contexts.back().IsExpression = false;
142 } else if (Left->Previous && Left->Previous->is(tok::kw___attribute)) {
143 Left->Type = TT_AttributeParen;
144 } else if (Left->Previous && Left->Previous->is(TT_ForEachMacro)) {
145 // The first argument to a foreach macro is a declaration.
146 Contexts.back().IsForEachMacro = true;
147 Contexts.back().IsExpression = false;
148 } else if (Left->Previous && Left->Previous->MatchingParen &&
149 Left->Previous->MatchingParen->is(TT_ObjCBlockLParen)) {
150 Contexts.back().IsExpression = false;
151 }
152
153 if (StartsObjCMethodExpr) {
154 Contexts.back().ColonIsObjCMethodExpr = true;
155 Left->Type = TT_ObjCMethodExpr;
156 }
157
158 bool MightBeFunctionType = CurrentToken->isOneOf(tok::star, tok::amp);
159 bool HasMultipleLines = false;
160 bool HasMultipleParametersOnALine = false;
161 bool MightBeObjCForRangeLoop =
162 Left->Previous && Left->Previous->is(tok::kw_for);
163 while (CurrentToken) {
164 // LookForDecls is set when "if (" has been seen. Check for
165 // 'identifier' '*' 'identifier' followed by not '=' -- this
166 // '*' has to be a binary operator but determineStarAmpUsage() will
167 // categorize it as an unary operator, so set the right type here.
168 if (LookForDecls && CurrentToken->Next) {
169 FormatToken *Prev = CurrentToken->getPreviousNonComment();
170 if (Prev) {
171 FormatToken *PrevPrev = Prev->getPreviousNonComment();
172 FormatToken *Next = CurrentToken->Next;
173 if (PrevPrev && PrevPrev->is(tok::identifier) &&
174 Prev->isOneOf(tok::star, tok::amp, tok::ampamp) &&
175 CurrentToken->is(tok::identifier) && Next->isNot(tok::equal)) {
176 Prev->Type = TT_BinaryOperator;
177 LookForDecls = false;
178 }
179 }
180 }
181
182 if (CurrentToken->Previous->is(TT_PointerOrReference) &&
183 CurrentToken->Previous->Previous->isOneOf(tok::l_paren,
184 tok::coloncolon))
185 MightBeFunctionType = true;
186 if (CurrentToken->Previous->is(TT_BinaryOperator))
187 Contexts.back().IsExpression = true;
188 if (CurrentToken->is(tok::r_paren)) {
189 if (MightBeFunctionType && CurrentToken->Next &&
190 (CurrentToken->Next->is(tok::l_paren) ||
191 (CurrentToken->Next->is(tok::l_square) &&
192 !Contexts.back().IsExpression)))
193 Left->Type = TT_FunctionTypeLParen;
194 Left->MatchingParen = CurrentToken;
195 CurrentToken->MatchingParen = Left;
196
197 if (StartsObjCMethodExpr) {
198 CurrentToken->Type = TT_ObjCMethodExpr;
199 if (Contexts.back().FirstObjCSelectorName) {
200 Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
201 Contexts.back().LongestObjCSelectorName;
202 }
203 }
204
205 if (Left->is(TT_AttributeParen))
206 CurrentToken->Type = TT_AttributeParen;
207 if (Left->Previous && Left->Previous->is(TT_JavaAnnotation))
208 CurrentToken->Type = TT_JavaAnnotation;
209 if (Left->Previous && Left->Previous->is(TT_LeadingJavaAnnotation))
210 CurrentToken->Type = TT_LeadingJavaAnnotation;
211
212 if (!HasMultipleLines)
213 Left->PackingKind = PPK_Inconclusive;
214 else if (HasMultipleParametersOnALine)
215 Left->PackingKind = PPK_BinPacked;
216 else
217 Left->PackingKind = PPK_OnePerLine;
218
219 next();
220 return true;
221 }
222 if (CurrentToken->isOneOf(tok::r_square, tok::r_brace))
223 return false;
224
225 if (CurrentToken->is(tok::l_brace))
226 Left->Type = TT_Unknown; // Not TT_ObjCBlockLParen
227 if (CurrentToken->is(tok::comma) && CurrentToken->Next &&
228 !CurrentToken->Next->HasUnescapedNewline &&
229 !CurrentToken->Next->isTrailingComment())
230 HasMultipleParametersOnALine = true;
231 if (CurrentToken->isOneOf(tok::kw_const, tok::kw_auto) ||
232 CurrentToken->isSimpleTypeSpecifier())
233 Contexts.back().IsExpression = false;
234 if (CurrentToken->isOneOf(tok::semi, tok::colon))
235 MightBeObjCForRangeLoop = false;
236 if (MightBeObjCForRangeLoop && CurrentToken->is(Keywords.kw_in))
237 CurrentToken->Type = TT_ObjCForIn;
238 // When we discover a 'new', we set CanBeExpression to 'false' in order to
239 // parse the type correctly. Reset that after a comma.
240 if (CurrentToken->is(tok::comma))
241 Contexts.back().CanBeExpression = true;
242
243 FormatToken *Tok = CurrentToken;
244 if (!consumeToken())
245 return false;
246 updateParameterCount(Left, Tok);
247 if (CurrentToken && CurrentToken->HasUnescapedNewline)
248 HasMultipleLines = true;
249 }
250 return false;
251 }
252
parseSquare()253 bool parseSquare() {
254 if (!CurrentToken)
255 return false;
256
257 // A '[' could be an index subscript (after an identifier or after
258 // ')' or ']'), it could be the start of an Objective-C method
259 // expression, or it could the start of an Objective-C array literal.
260 FormatToken *Left = CurrentToken->Previous;
261 Left->ParentBracket = Contexts.back().ContextKind;
262 FormatToken *Parent = Left->getPreviousNonComment();
263 bool StartsObjCMethodExpr =
264 Style.Language == FormatStyle::LK_Cpp &&
265 Contexts.back().CanBeExpression && Left->isNot(TT_LambdaLSquare) &&
266 CurrentToken->isNot(tok::l_brace) &&
267 (!Parent ||
268 Parent->isOneOf(tok::colon, tok::l_square, tok::l_paren,
269 tok::kw_return, tok::kw_throw) ||
270 Parent->isUnaryOperator() ||
271 Parent->isOneOf(TT_ObjCForIn, TT_CastRParen) ||
272 getBinOpPrecedence(Parent->Tok.getKind(), true, true) > prec::Unknown);
273 bool ColonFound = false;
274
275 unsigned BindingIncrease = 1;
276 if (Left->is(TT_Unknown)) {
277 if (StartsObjCMethodExpr) {
278 Left->Type = TT_ObjCMethodExpr;
279 } else if (Style.Language == FormatStyle::LK_JavaScript && Parent &&
280 Contexts.back().ContextKind == tok::l_brace &&
281 Parent->isOneOf(tok::l_brace, tok::comma)) {
282 Left->Type = TT_JsComputedPropertyName;
283 } else if (Parent &&
284 Parent->isOneOf(tok::at, tok::equal, tok::comma, tok::l_paren,
285 tok::l_square, tok::question, tok::colon,
286 tok::kw_return)) {
287 Left->Type = TT_ArrayInitializerLSquare;
288 } else {
289 BindingIncrease = 10;
290 Left->Type = TT_ArraySubscriptLSquare;
291 }
292 }
293
294 ScopedContextCreator ContextCreator(*this, tok::l_square, BindingIncrease);
295 Contexts.back().IsExpression = true;
296 Contexts.back().ColonIsObjCMethodExpr = StartsObjCMethodExpr;
297
298 while (CurrentToken) {
299 if (CurrentToken->is(tok::r_square)) {
300 if (CurrentToken->Next && CurrentToken->Next->is(tok::l_paren) &&
301 Left->is(TT_ObjCMethodExpr)) {
302 // An ObjC method call is rarely followed by an open parenthesis.
303 // FIXME: Do we incorrectly label ":" with this?
304 StartsObjCMethodExpr = false;
305 Left->Type = TT_Unknown;
306 }
307 if (StartsObjCMethodExpr && CurrentToken->Previous != Left) {
308 CurrentToken->Type = TT_ObjCMethodExpr;
309 // determineStarAmpUsage() thinks that '*' '[' is allocating an
310 // array of pointers, but if '[' starts a selector then '*' is a
311 // binary operator.
312 if (Parent && Parent->is(TT_PointerOrReference))
313 Parent->Type = TT_BinaryOperator;
314 }
315 Left->MatchingParen = CurrentToken;
316 CurrentToken->MatchingParen = Left;
317 if (Contexts.back().FirstObjCSelectorName) {
318 Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
319 Contexts.back().LongestObjCSelectorName;
320 if (Left->BlockParameterCount > 1)
321 Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName = 0;
322 }
323 next();
324 return true;
325 }
326 if (CurrentToken->isOneOf(tok::r_paren, tok::r_brace))
327 return false;
328 if (CurrentToken->is(tok::colon)) {
329 if (Left->is(TT_ArraySubscriptLSquare)) {
330 Left->Type = TT_ObjCMethodExpr;
331 StartsObjCMethodExpr = true;
332 Contexts.back().ColonIsObjCMethodExpr = true;
333 if (Parent && Parent->is(tok::r_paren))
334 Parent->Type = TT_CastRParen;
335 }
336 ColonFound = true;
337 }
338 if (CurrentToken->is(tok::comma) && Left->is(TT_ObjCMethodExpr) &&
339 !ColonFound)
340 Left->Type = TT_ArrayInitializerLSquare;
341 FormatToken *Tok = CurrentToken;
342 if (!consumeToken())
343 return false;
344 updateParameterCount(Left, Tok);
345 }
346 return false;
347 }
348
parseBrace()349 bool parseBrace() {
350 if (CurrentToken) {
351 FormatToken *Left = CurrentToken->Previous;
352 Left->ParentBracket = Contexts.back().ContextKind;
353
354 if (Contexts.back().CaretFound)
355 Left->Type = TT_ObjCBlockLBrace;
356 Contexts.back().CaretFound = false;
357
358 ScopedContextCreator ContextCreator(*this, tok::l_brace, 1);
359 Contexts.back().ColonIsDictLiteral = true;
360 if (Left->BlockKind == BK_BracedInit)
361 Contexts.back().IsExpression = true;
362
363 while (CurrentToken) {
364 if (CurrentToken->is(tok::r_brace)) {
365 Left->MatchingParen = CurrentToken;
366 CurrentToken->MatchingParen = Left;
367 next();
368 return true;
369 }
370 if (CurrentToken->isOneOf(tok::r_paren, tok::r_square))
371 return false;
372 updateParameterCount(Left, CurrentToken);
373 if (CurrentToken->isOneOf(tok::colon, tok::l_brace)) {
374 FormatToken *Previous = CurrentToken->getPreviousNonComment();
375 if (((CurrentToken->is(tok::colon) &&
376 (!Contexts.back().ColonIsDictLiteral ||
377 Style.Language != FormatStyle::LK_Cpp)) ||
378 Style.Language == FormatStyle::LK_Proto) &&
379 Previous->Tok.getIdentifierInfo())
380 Previous->Type = TT_SelectorName;
381 if (CurrentToken->is(tok::colon) ||
382 Style.Language == FormatStyle::LK_JavaScript)
383 Left->Type = TT_DictLiteral;
384 }
385 if (!consumeToken())
386 return false;
387 }
388 }
389 return true;
390 }
391
updateParameterCount(FormatToken * Left,FormatToken * Current)392 void updateParameterCount(FormatToken *Left, FormatToken *Current) {
393 if (Current->is(tok::l_brace) && !Current->is(TT_DictLiteral))
394 ++Left->BlockParameterCount;
395 if (Current->is(tok::comma)) {
396 ++Left->ParameterCount;
397 if (!Left->Role)
398 Left->Role.reset(new CommaSeparatedList(Style));
399 Left->Role->CommaFound(Current);
400 } else if (Left->ParameterCount == 0 && Current->isNot(tok::comment)) {
401 Left->ParameterCount = 1;
402 }
403 }
404
parseConditional()405 bool parseConditional() {
406 while (CurrentToken) {
407 if (CurrentToken->is(tok::colon)) {
408 CurrentToken->Type = TT_ConditionalExpr;
409 next();
410 return true;
411 }
412 if (!consumeToken())
413 return false;
414 }
415 return false;
416 }
417
parseTemplateDeclaration()418 bool parseTemplateDeclaration() {
419 if (CurrentToken && CurrentToken->is(tok::less)) {
420 CurrentToken->Type = TT_TemplateOpener;
421 next();
422 if (!parseAngle())
423 return false;
424 if (CurrentToken)
425 CurrentToken->Previous->ClosesTemplateDeclaration = true;
426 return true;
427 }
428 return false;
429 }
430
consumeToken()431 bool consumeToken() {
432 FormatToken *Tok = CurrentToken;
433 next();
434 switch (Tok->Tok.getKind()) {
435 case tok::plus:
436 case tok::minus:
437 if (!Tok->Previous && Line.MustBeDeclaration)
438 Tok->Type = TT_ObjCMethodSpecifier;
439 break;
440 case tok::colon:
441 if (!Tok->Previous)
442 return false;
443 // Colons from ?: are handled in parseConditional().
444 if (Style.Language == FormatStyle::LK_JavaScript) {
445 if (Contexts.back().ColonIsForRangeExpr || // colon in for loop
446 (Contexts.size() == 1 && // switch/case labels
447 !Line.First->isOneOf(tok::kw_enum, tok::kw_case)) ||
448 Contexts.back().ContextKind == tok::l_paren || // function params
449 Contexts.back().ContextKind == tok::l_square || // array type
450 (Contexts.size() == 1 &&
451 Line.MustBeDeclaration)) { // method/property declaration
452 Tok->Type = TT_JsTypeColon;
453 break;
454 }
455 }
456 if (Contexts.back().ColonIsDictLiteral) {
457 Tok->Type = TT_DictLiteral;
458 } else if (Contexts.back().ColonIsObjCMethodExpr ||
459 Line.startsWith(TT_ObjCMethodSpecifier)) {
460 Tok->Type = TT_ObjCMethodExpr;
461 Tok->Previous->Type = TT_SelectorName;
462 if (Tok->Previous->ColumnWidth >
463 Contexts.back().LongestObjCSelectorName) {
464 Contexts.back().LongestObjCSelectorName = Tok->Previous->ColumnWidth;
465 }
466 if (!Contexts.back().FirstObjCSelectorName)
467 Contexts.back().FirstObjCSelectorName = Tok->Previous;
468 } else if (Contexts.back().ColonIsForRangeExpr) {
469 Tok->Type = TT_RangeBasedForLoopColon;
470 } else if (CurrentToken && CurrentToken->is(tok::numeric_constant)) {
471 Tok->Type = TT_BitFieldColon;
472 } else if (Contexts.size() == 1 &&
473 !Line.First->isOneOf(tok::kw_enum, tok::kw_case)) {
474 if (Tok->Previous->is(tok::r_paren))
475 Tok->Type = TT_CtorInitializerColon;
476 else
477 Tok->Type = TT_InheritanceColon;
478 } else if (Tok->Previous->is(tok::identifier) && Tok->Next &&
479 Tok->Next->isOneOf(tok::r_paren, tok::comma)) {
480 // This handles a special macro in ObjC code where selectors including
481 // the colon are passed as macro arguments.
482 Tok->Type = TT_ObjCMethodExpr;
483 } else if (Contexts.back().ContextKind == tok::l_paren) {
484 Tok->Type = TT_InlineASMColon;
485 }
486 break;
487 case tok::kw_if:
488 case tok::kw_while:
489 if (CurrentToken && CurrentToken->is(tok::l_paren)) {
490 next();
491 if (!parseParens(/*LookForDecls=*/true))
492 return false;
493 }
494 break;
495 case tok::kw_for:
496 Contexts.back().ColonIsForRangeExpr = true;
497 next();
498 if (!parseParens())
499 return false;
500 break;
501 case tok::l_paren:
502 // When faced with 'operator()()', the kw_operator handler incorrectly
503 // marks the first l_paren as a OverloadedOperatorLParen. Here, we make
504 // the first two parens OverloadedOperators and the second l_paren an
505 // OverloadedOperatorLParen.
506 if (Tok->Previous &&
507 Tok->Previous->is(tok::r_paren) &&
508 Tok->Previous->MatchingParen &&
509 Tok->Previous->MatchingParen->is(TT_OverloadedOperatorLParen)) {
510 Tok->Previous->Type = TT_OverloadedOperator;
511 Tok->Previous->MatchingParen->Type = TT_OverloadedOperator;
512 Tok->Type = TT_OverloadedOperatorLParen;
513 }
514
515 if (!parseParens())
516 return false;
517 if (Line.MustBeDeclaration && Contexts.size() == 1 &&
518 !Contexts.back().IsExpression && !Line.startsWith(TT_ObjCProperty) &&
519 (!Tok->Previous ||
520 !Tok->Previous->isOneOf(tok::kw_decltype, tok::kw___attribute,
521 TT_LeadingJavaAnnotation)))
522 Line.MightBeFunctionDecl = true;
523 break;
524 case tok::l_square:
525 if (!parseSquare())
526 return false;
527 break;
528 case tok::l_brace:
529 if (!parseBrace())
530 return false;
531 break;
532 case tok::less:
533 if (!NonTemplateLess.count(Tok) &&
534 (!Tok->Previous ||
535 (!Tok->Previous->Tok.isLiteral() &&
536 !(Tok->Previous->is(tok::r_paren) && Contexts.size() > 1))) &&
537 parseAngle()) {
538 Tok->Type = TT_TemplateOpener;
539 } else {
540 Tok->Type = TT_BinaryOperator;
541 NonTemplateLess.insert(Tok);
542 CurrentToken = Tok;
543 next();
544 }
545 break;
546 case tok::r_paren:
547 case tok::r_square:
548 return false;
549 case tok::r_brace:
550 // Lines can start with '}'.
551 if (Tok->Previous)
552 return false;
553 break;
554 case tok::greater:
555 Tok->Type = TT_BinaryOperator;
556 break;
557 case tok::kw_operator:
558 while (CurrentToken &&
559 !CurrentToken->isOneOf(tok::l_paren, tok::semi, tok::r_paren)) {
560 if (CurrentToken->isOneOf(tok::star, tok::amp))
561 CurrentToken->Type = TT_PointerOrReference;
562 consumeToken();
563 if (CurrentToken && CurrentToken->Previous->is(TT_BinaryOperator))
564 CurrentToken->Previous->Type = TT_OverloadedOperator;
565 }
566 if (CurrentToken) {
567 CurrentToken->Type = TT_OverloadedOperatorLParen;
568 if (CurrentToken->Previous->is(TT_BinaryOperator))
569 CurrentToken->Previous->Type = TT_OverloadedOperator;
570 }
571 break;
572 case tok::question:
573 if (Style.Language == FormatStyle::LK_JavaScript && Tok->Next &&
574 Tok->Next->isOneOf(tok::semi, tok::comma, tok::colon, tok::r_paren,
575 tok::r_brace)) {
576 // Question marks before semicolons, colons, etc. indicate optional
577 // types (fields, parameters), e.g.
578 // function(x?: string, y?) {...}
579 // class X { y?; }
580 Tok->Type = TT_JsTypeOptionalQuestion;
581 break;
582 }
583 // Declarations cannot be conditional expressions, this can only be part
584 // of a type declaration.
585 if (Line.MustBeDeclaration &&
586 Style.Language == FormatStyle::LK_JavaScript)
587 break;
588 parseConditional();
589 break;
590 case tok::kw_template:
591 parseTemplateDeclaration();
592 break;
593 case tok::comma:
594 if (Contexts.back().InCtorInitializer)
595 Tok->Type = TT_CtorInitializerComma;
596 else if (Contexts.back().FirstStartOfName &&
597 (Contexts.size() == 1 || Line.startsWith(tok::kw_for))) {
598 Contexts.back().FirstStartOfName->PartOfMultiVariableDeclStmt = true;
599 Line.IsMultiVariableDeclStmt = true;
600 }
601 if (Contexts.back().IsForEachMacro)
602 Contexts.back().IsExpression = true;
603 break;
604 default:
605 break;
606 }
607 return true;
608 }
609
parseIncludeDirective()610 void parseIncludeDirective() {
611 if (CurrentToken && CurrentToken->is(tok::less)) {
612 next();
613 while (CurrentToken) {
614 if (CurrentToken->isNot(tok::comment) || CurrentToken->Next)
615 CurrentToken->Type = TT_ImplicitStringLiteral;
616 next();
617 }
618 }
619 }
620
parseWarningOrError()621 void parseWarningOrError() {
622 next();
623 // We still want to format the whitespace left of the first token of the
624 // warning or error.
625 next();
626 while (CurrentToken) {
627 CurrentToken->Type = TT_ImplicitStringLiteral;
628 next();
629 }
630 }
631
parsePragma()632 void parsePragma() {
633 next(); // Consume "pragma".
634 if (CurrentToken &&
635 CurrentToken->isOneOf(Keywords.kw_mark, Keywords.kw_option)) {
636 bool IsMark = CurrentToken->is(Keywords.kw_mark);
637 next(); // Consume "mark".
638 next(); // Consume first token (so we fix leading whitespace).
639 while (CurrentToken) {
640 if (IsMark || CurrentToken->Previous->is(TT_BinaryOperator))
641 CurrentToken->Type = TT_ImplicitStringLiteral;
642 next();
643 }
644 }
645 }
646
parsePreprocessorDirective()647 LineType parsePreprocessorDirective() {
648 LineType Type = LT_PreprocessorDirective;
649 next();
650 if (!CurrentToken)
651 return Type;
652 if (CurrentToken->Tok.is(tok::numeric_constant)) {
653 CurrentToken->SpacesRequiredBefore = 1;
654 return Type;
655 }
656 // Hashes in the middle of a line can lead to any strange token
657 // sequence.
658 if (!CurrentToken->Tok.getIdentifierInfo())
659 return Type;
660 switch (CurrentToken->Tok.getIdentifierInfo()->getPPKeywordID()) {
661 case tok::pp_include:
662 case tok::pp_include_next:
663 case tok::pp_import:
664 next();
665 parseIncludeDirective();
666 Type = LT_ImportStatement;
667 break;
668 case tok::pp_error:
669 case tok::pp_warning:
670 parseWarningOrError();
671 break;
672 case tok::pp_pragma:
673 parsePragma();
674 break;
675 case tok::pp_if:
676 case tok::pp_elif:
677 Contexts.back().IsExpression = true;
678 parseLine();
679 break;
680 default:
681 break;
682 }
683 while (CurrentToken)
684 next();
685 return Type;
686 }
687
688 public:
parseLine()689 LineType parseLine() {
690 NonTemplateLess.clear();
691 if (CurrentToken->is(tok::hash))
692 return parsePreprocessorDirective();
693
694 // Directly allow to 'import <string-literal>' to support protocol buffer
695 // definitions (code.google.com/p/protobuf) or missing "#" (either way we
696 // should not break the line).
697 IdentifierInfo *Info = CurrentToken->Tok.getIdentifierInfo();
698 if ((Style.Language == FormatStyle::LK_Java &&
699 CurrentToken->is(Keywords.kw_package)) ||
700 (Info && Info->getPPKeywordID() == tok::pp_import &&
701 CurrentToken->Next &&
702 CurrentToken->Next->isOneOf(tok::string_literal, tok::identifier,
703 tok::kw_static))) {
704 next();
705 parseIncludeDirective();
706 return LT_ImportStatement;
707 }
708
709 // If this line starts and ends in '<' and '>', respectively, it is likely
710 // part of "#define <a/b.h>".
711 if (CurrentToken->is(tok::less) && Line.Last->is(tok::greater)) {
712 parseIncludeDirective();
713 return LT_ImportStatement;
714 }
715
716 // In .proto files, top-level options are very similar to import statements
717 // and should not be line-wrapped.
718 if (Style.Language == FormatStyle::LK_Proto && Line.Level == 0 &&
719 CurrentToken->is(Keywords.kw_option)) {
720 next();
721 if (CurrentToken && CurrentToken->is(tok::identifier))
722 return LT_ImportStatement;
723 }
724
725 bool KeywordVirtualFound = false;
726 bool ImportStatement = false;
727 while (CurrentToken) {
728 if (CurrentToken->is(tok::kw_virtual))
729 KeywordVirtualFound = true;
730 if (isImportStatement(*CurrentToken))
731 ImportStatement = true;
732 if (!consumeToken())
733 return LT_Invalid;
734 }
735 if (KeywordVirtualFound)
736 return LT_VirtualFunctionDecl;
737 if (ImportStatement)
738 return LT_ImportStatement;
739
740 if (Line.startsWith(TT_ObjCMethodSpecifier)) {
741 if (Contexts.back().FirstObjCSelectorName)
742 Contexts.back().FirstObjCSelectorName->LongestObjCSelectorName =
743 Contexts.back().LongestObjCSelectorName;
744 return LT_ObjCMethodDecl;
745 }
746
747 return LT_Other;
748 }
749
750 private:
isImportStatement(const FormatToken & Tok)751 bool isImportStatement(const FormatToken &Tok) {
752 // FIXME: Closure-library specific stuff should not be hard-coded but be
753 // configurable.
754 return Style.Language == FormatStyle::LK_JavaScript &&
755 Tok.TokenText == "goog" && Tok.Next && Tok.Next->is(tok::period) &&
756 Tok.Next->Next && (Tok.Next->Next->TokenText == "module" ||
757 Tok.Next->Next->TokenText == "provide" ||
758 Tok.Next->Next->TokenText == "require" ||
759 Tok.Next->Next->TokenText == "setTestOnly") &&
760 Tok.Next->Next->Next && Tok.Next->Next->Next->is(tok::l_paren);
761 }
762
resetTokenMetadata(FormatToken * Token)763 void resetTokenMetadata(FormatToken *Token) {
764 if (!Token)
765 return;
766
767 // Reset token type in case we have already looked at it and then
768 // recovered from an error (e.g. failure to find the matching >).
769 if (!CurrentToken->isOneOf(TT_LambdaLSquare, TT_ForEachMacro,
770 TT_FunctionLBrace, TT_ImplicitStringLiteral,
771 TT_InlineASMBrace, TT_JsFatArrow, TT_LambdaArrow,
772 TT_RegexLiteral))
773 CurrentToken->Type = TT_Unknown;
774 CurrentToken->Role.reset();
775 CurrentToken->MatchingParen = nullptr;
776 CurrentToken->FakeLParens.clear();
777 CurrentToken->FakeRParens = 0;
778 }
779
next()780 void next() {
781 if (CurrentToken) {
782 CurrentToken->NestingLevel = Contexts.size() - 1;
783 CurrentToken->BindingStrength = Contexts.back().BindingStrength;
784 modifyContext(*CurrentToken);
785 determineTokenType(*CurrentToken);
786 CurrentToken = CurrentToken->Next;
787 }
788
789 resetTokenMetadata(CurrentToken);
790 }
791
792 /// \brief A struct to hold information valid in a specific context, e.g.
793 /// a pair of parenthesis.
794 struct Context {
Contextclang::format::__anon7c513deb0111::AnnotatingParser::Context795 Context(tok::TokenKind ContextKind, unsigned BindingStrength,
796 bool IsExpression)
797 : ContextKind(ContextKind), BindingStrength(BindingStrength),
798 IsExpression(IsExpression) {}
799
800 tok::TokenKind ContextKind;
801 unsigned BindingStrength;
802 bool IsExpression;
803 unsigned LongestObjCSelectorName = 0;
804 bool ColonIsForRangeExpr = false;
805 bool ColonIsDictLiteral = false;
806 bool ColonIsObjCMethodExpr = false;
807 FormatToken *FirstObjCSelectorName = nullptr;
808 FormatToken *FirstStartOfName = nullptr;
809 bool CanBeExpression = true;
810 bool InTemplateArgument = false;
811 bool InCtorInitializer = false;
812 bool CaretFound = false;
813 bool IsForEachMacro = false;
814 };
815
816 /// \brief Puts a new \c Context onto the stack \c Contexts for the lifetime
817 /// of each instance.
818 struct ScopedContextCreator {
819 AnnotatingParser &P;
820
ScopedContextCreatorclang::format::__anon7c513deb0111::AnnotatingParser::ScopedContextCreator821 ScopedContextCreator(AnnotatingParser &P, tok::TokenKind ContextKind,
822 unsigned Increase)
823 : P(P) {
824 P.Contexts.push_back(Context(ContextKind,
825 P.Contexts.back().BindingStrength + Increase,
826 P.Contexts.back().IsExpression));
827 }
828
~ScopedContextCreatorclang::format::__anon7c513deb0111::AnnotatingParser::ScopedContextCreator829 ~ScopedContextCreator() { P.Contexts.pop_back(); }
830 };
831
modifyContext(const FormatToken & Current)832 void modifyContext(const FormatToken &Current) {
833 if (Current.getPrecedence() == prec::Assignment &&
834 !Line.First->isOneOf(tok::kw_template, tok::kw_using) &&
835 (!Current.Previous || Current.Previous->isNot(tok::kw_operator))) {
836 Contexts.back().IsExpression = true;
837 if (!Line.startsWith(TT_UnaryOperator)) {
838 for (FormatToken *Previous = Current.Previous;
839 Previous && Previous->Previous &&
840 !Previous->Previous->isOneOf(tok::comma, tok::semi);
841 Previous = Previous->Previous) {
842 if (Previous->isOneOf(tok::r_square, tok::r_paren)) {
843 Previous = Previous->MatchingParen;
844 if (!Previous)
845 break;
846 }
847 if (Previous->opensScope())
848 break;
849 if (Previous->isOneOf(TT_BinaryOperator, TT_UnaryOperator) &&
850 Previous->isOneOf(tok::star, tok::amp, tok::ampamp) &&
851 Previous->Previous && Previous->Previous->isNot(tok::equal))
852 Previous->Type = TT_PointerOrReference;
853 }
854 }
855 } else if (Current.is(tok::lessless) &&
856 (!Current.Previous || !Current.Previous->is(tok::kw_operator))) {
857 Contexts.back().IsExpression = true;
858 } else if (Current.isOneOf(tok::kw_return, tok::kw_throw)) {
859 Contexts.back().IsExpression = true;
860 } else if (Current.is(TT_TrailingReturnArrow)) {
861 Contexts.back().IsExpression = false;
862 } else if (Current.is(TT_LambdaArrow) || Current.is(Keywords.kw_assert)) {
863 Contexts.back().IsExpression = Style.Language == FormatStyle::LK_Java;
864 } else if (Current.is(tok::l_paren) && !Line.MustBeDeclaration &&
865 !Line.InPPDirective &&
866 (!Current.Previous ||
867 Current.Previous->isNot(tok::kw_decltype))) {
868 bool ParametersOfFunctionType =
869 Current.Previous && Current.Previous->is(tok::r_paren) &&
870 Current.Previous->MatchingParen &&
871 Current.Previous->MatchingParen->is(TT_FunctionTypeLParen);
872 bool IsForOrCatch = Current.Previous &&
873 Current.Previous->isOneOf(tok::kw_for, tok::kw_catch);
874 Contexts.back().IsExpression = !ParametersOfFunctionType && !IsForOrCatch;
875 } else if (Current.isOneOf(tok::r_paren, tok::greater, tok::comma)) {
876 for (FormatToken *Previous = Current.Previous;
877 Previous && Previous->isOneOf(tok::star, tok::amp);
878 Previous = Previous->Previous)
879 Previous->Type = TT_PointerOrReference;
880 if (Line.MustBeDeclaration)
881 Contexts.back().IsExpression = Contexts.front().InCtorInitializer;
882 } else if (Current.Previous &&
883 Current.Previous->is(TT_CtorInitializerColon)) {
884 Contexts.back().IsExpression = true;
885 Contexts.back().InCtorInitializer = true;
886 } else if (Current.is(tok::kw_new)) {
887 Contexts.back().CanBeExpression = false;
888 } else if (Current.isOneOf(tok::semi, tok::exclaim)) {
889 // This should be the condition or increment in a for-loop.
890 Contexts.back().IsExpression = true;
891 }
892 }
893
determineTokenType(FormatToken & Current)894 void determineTokenType(FormatToken &Current) {
895 if (!Current.is(TT_Unknown))
896 // The token type is already known.
897 return;
898
899 // Line.MightBeFunctionDecl can only be true after the parentheses of a
900 // function declaration have been found. In this case, 'Current' is a
901 // trailing token of this declaration and thus cannot be a name.
902 if (Current.is(Keywords.kw_instanceof)) {
903 Current.Type = TT_BinaryOperator;
904 } else if (isStartOfName(Current) &&
905 (!Line.MightBeFunctionDecl || Current.NestingLevel != 0)) {
906 Contexts.back().FirstStartOfName = &Current;
907 Current.Type = TT_StartOfName;
908 } else if (Current.isOneOf(tok::kw_auto, tok::kw___auto_type)) {
909 AutoFound = true;
910 } else if (Current.is(tok::arrow) &&
911 Style.Language == FormatStyle::LK_Java) {
912 Current.Type = TT_LambdaArrow;
913 } else if (Current.is(tok::arrow) && AutoFound && Line.MustBeDeclaration &&
914 Current.NestingLevel == 0) {
915 Current.Type = TT_TrailingReturnArrow;
916 } else if (Current.isOneOf(tok::star, tok::amp, tok::ampamp)) {
917 Current.Type =
918 determineStarAmpUsage(Current, Contexts.back().CanBeExpression &&
919 Contexts.back().IsExpression,
920 Contexts.back().InTemplateArgument);
921 } else if (Current.isOneOf(tok::minus, tok::plus, tok::caret)) {
922 Current.Type = determinePlusMinusCaretUsage(Current);
923 if (Current.is(TT_UnaryOperator) && Current.is(tok::caret))
924 Contexts.back().CaretFound = true;
925 } else if (Current.isOneOf(tok::minusminus, tok::plusplus)) {
926 Current.Type = determineIncrementUsage(Current);
927 } else if (Current.isOneOf(tok::exclaim, tok::tilde)) {
928 Current.Type = TT_UnaryOperator;
929 } else if (Current.is(tok::question)) {
930 if (Style.Language == FormatStyle::LK_JavaScript &&
931 Line.MustBeDeclaration) {
932 // In JavaScript, `interface X { foo?(): bar; }` is an optional method
933 // on the interface, not a ternary expression.
934 Current.Type = TT_JsTypeOptionalQuestion;
935 } else {
936 Current.Type = TT_ConditionalExpr;
937 }
938 } else if (Current.isBinaryOperator() &&
939 (!Current.Previous || Current.Previous->isNot(tok::l_square))) {
940 Current.Type = TT_BinaryOperator;
941 } else if (Current.is(tok::comment)) {
942 if (Current.TokenText.startswith("/*")) {
943 if (Current.TokenText.endswith("*/"))
944 Current.Type = TT_BlockComment;
945 else
946 // The lexer has for some reason determined a comment here. But we
947 // cannot really handle it, if it isn't properly terminated.
948 Current.Tok.setKind(tok::unknown);
949 } else {
950 Current.Type = TT_LineComment;
951 }
952 } else if (Current.is(tok::r_paren)) {
953 if (rParenEndsCast(Current))
954 Current.Type = TT_CastRParen;
955 if (Current.MatchingParen && Current.Next &&
956 !Current.Next->isBinaryOperator() &&
957 !Current.Next->isOneOf(tok::semi, tok::colon, tok::l_brace))
958 if (FormatToken *BeforeParen = Current.MatchingParen->Previous)
959 if (BeforeParen->is(tok::identifier) &&
960 BeforeParen->TokenText == BeforeParen->TokenText.upper() &&
961 (!BeforeParen->Previous ||
962 BeforeParen->Previous->ClosesTemplateDeclaration))
963 Current.Type = TT_FunctionAnnotationRParen;
964 } else if (Current.is(tok::at) && Current.Next) {
965 if (Current.Next->isStringLiteral()) {
966 Current.Type = TT_ObjCStringLiteral;
967 } else {
968 switch (Current.Next->Tok.getObjCKeywordID()) {
969 case tok::objc_interface:
970 case tok::objc_implementation:
971 case tok::objc_protocol:
972 Current.Type = TT_ObjCDecl;
973 break;
974 case tok::objc_property:
975 Current.Type = TT_ObjCProperty;
976 break;
977 default:
978 break;
979 }
980 }
981 } else if (Current.is(tok::period)) {
982 FormatToken *PreviousNoComment = Current.getPreviousNonComment();
983 if (PreviousNoComment &&
984 PreviousNoComment->isOneOf(tok::comma, tok::l_brace))
985 Current.Type = TT_DesignatedInitializerPeriod;
986 else if (Style.Language == FormatStyle::LK_Java && Current.Previous &&
987 Current.Previous->isOneOf(TT_JavaAnnotation,
988 TT_LeadingJavaAnnotation)) {
989 Current.Type = Current.Previous->Type;
990 }
991 } else if (Current.isOneOf(tok::identifier, tok::kw_const) &&
992 Current.Previous &&
993 !Current.Previous->isOneOf(tok::equal, tok::at) &&
994 Line.MightBeFunctionDecl && Contexts.size() == 1) {
995 // Line.MightBeFunctionDecl can only be true after the parentheses of a
996 // function declaration have been found.
997 Current.Type = TT_TrailingAnnotation;
998 } else if ((Style.Language == FormatStyle::LK_Java ||
999 Style.Language == FormatStyle::LK_JavaScript) &&
1000 Current.Previous) {
1001 if (Current.Previous->is(tok::at) &&
1002 Current.isNot(Keywords.kw_interface)) {
1003 const FormatToken &AtToken = *Current.Previous;
1004 const FormatToken *Previous = AtToken.getPreviousNonComment();
1005 if (!Previous || Previous->is(TT_LeadingJavaAnnotation))
1006 Current.Type = TT_LeadingJavaAnnotation;
1007 else
1008 Current.Type = TT_JavaAnnotation;
1009 } else if (Current.Previous->is(tok::period) &&
1010 Current.Previous->isOneOf(TT_JavaAnnotation,
1011 TT_LeadingJavaAnnotation)) {
1012 Current.Type = Current.Previous->Type;
1013 }
1014 }
1015 }
1016
1017 /// \brief Take a guess at whether \p Tok starts a name of a function or
1018 /// variable declaration.
1019 ///
1020 /// This is a heuristic based on whether \p Tok is an identifier following
1021 /// something that is likely a type.
isStartOfName(const FormatToken & Tok)1022 bool isStartOfName(const FormatToken &Tok) {
1023 if (Tok.isNot(tok::identifier) || !Tok.Previous)
1024 return false;
1025
1026 if (Tok.Previous->isOneOf(TT_LeadingJavaAnnotation, Keywords.kw_instanceof))
1027 return false;
1028
1029 // Skip "const" as it does not have an influence on whether this is a name.
1030 FormatToken *PreviousNotConst = Tok.Previous;
1031 while (PreviousNotConst && PreviousNotConst->is(tok::kw_const))
1032 PreviousNotConst = PreviousNotConst->Previous;
1033
1034 if (!PreviousNotConst)
1035 return false;
1036
1037 bool IsPPKeyword = PreviousNotConst->is(tok::identifier) &&
1038 PreviousNotConst->Previous &&
1039 PreviousNotConst->Previous->is(tok::hash);
1040
1041 if (PreviousNotConst->is(TT_TemplateCloser))
1042 return PreviousNotConst && PreviousNotConst->MatchingParen &&
1043 PreviousNotConst->MatchingParen->Previous &&
1044 PreviousNotConst->MatchingParen->Previous->isNot(tok::period) &&
1045 PreviousNotConst->MatchingParen->Previous->isNot(tok::kw_template);
1046
1047 if (PreviousNotConst->is(tok::r_paren) && PreviousNotConst->MatchingParen &&
1048 PreviousNotConst->MatchingParen->Previous &&
1049 PreviousNotConst->MatchingParen->Previous->is(tok::kw_decltype))
1050 return true;
1051
1052 return (!IsPPKeyword &&
1053 PreviousNotConst->isOneOf(tok::identifier, tok::kw_auto)) ||
1054 PreviousNotConst->is(TT_PointerOrReference) ||
1055 PreviousNotConst->isSimpleTypeSpecifier();
1056 }
1057
1058 /// \brief Determine whether ')' is ending a cast.
rParenEndsCast(const FormatToken & Tok)1059 bool rParenEndsCast(const FormatToken &Tok) {
1060 // C-style casts are only used in C++ and Java.
1061 if (Style.Language != FormatStyle::LK_Cpp &&
1062 Style.Language != FormatStyle::LK_Java)
1063 return false;
1064
1065 // Empty parens aren't casts and there are no casts at the end of the line.
1066 if (Tok.Previous == Tok.MatchingParen || !Tok.Next || !Tok.MatchingParen)
1067 return false;
1068
1069 FormatToken *LeftOfParens = Tok.MatchingParen->getPreviousNonComment();
1070 if (LeftOfParens) {
1071 // If there is an opening parenthesis left of the current parentheses,
1072 // look past it as these might be chained casts.
1073 if (LeftOfParens->is(tok::r_paren)) {
1074 if (!LeftOfParens->MatchingParen ||
1075 !LeftOfParens->MatchingParen->Previous)
1076 return false;
1077 LeftOfParens = LeftOfParens->MatchingParen->Previous;
1078 }
1079
1080 // If there is an identifier (or with a few exceptions a keyword) right
1081 // before the parentheses, this is unlikely to be a cast.
1082 if (LeftOfParens->Tok.getIdentifierInfo() &&
1083 !LeftOfParens->isOneOf(Keywords.kw_in, tok::kw_return, tok::kw_case,
1084 tok::kw_delete))
1085 return false;
1086
1087 // Certain other tokens right before the parentheses are also signals that
1088 // this cannot be a cast.
1089 if (LeftOfParens->isOneOf(tok::at, tok::r_square, TT_OverloadedOperator,
1090 TT_TemplateCloser))
1091 return false;
1092 }
1093
1094 if (Tok.Next->is(tok::question))
1095 return false;
1096
1097 // As Java has no function types, a "(" after the ")" likely means that this
1098 // is a cast.
1099 if (Style.Language == FormatStyle::LK_Java && Tok.Next->is(tok::l_paren))
1100 return true;
1101
1102 // If a (non-string) literal follows, this is likely a cast.
1103 if (Tok.Next->isNot(tok::string_literal) &&
1104 (Tok.Next->Tok.isLiteral() ||
1105 Tok.Next->isOneOf(tok::kw_sizeof, tok::kw_alignof)))
1106 return true;
1107
1108 // Heuristically try to determine whether the parentheses contain a type.
1109 bool ParensAreType =
1110 !Tok.Previous ||
1111 Tok.Previous->isOneOf(TT_PointerOrReference, TT_TemplateCloser) ||
1112 Tok.Previous->isSimpleTypeSpecifier();
1113 bool ParensCouldEndDecl =
1114 Tok.Next->isOneOf(tok::equal, tok::semi, tok::l_brace, tok::greater);
1115 if (ParensAreType && !ParensCouldEndDecl &&
1116 (Contexts.size() > 1 && Contexts[Contexts.size() - 2].IsExpression))
1117 return true;
1118
1119 // At this point, we heuristically assume that there are no casts at the
1120 // start of the line. We assume that we have found most cases where there
1121 // are by the logic above, e.g. "(void)x;".
1122 if (!LeftOfParens)
1123 return false;
1124
1125 // If the following token is an identifier, this is a cast. All cases where
1126 // this can be something else are handled above.
1127 if (Tok.Next->is(tok::identifier))
1128 return true;
1129
1130 if (!Tok.Next->Next)
1131 return false;
1132
1133 // If the next token after the parenthesis is a unary operator, assume
1134 // that this is cast, unless there are unexpected tokens inside the
1135 // parenthesis.
1136 bool NextIsUnary =
1137 Tok.Next->isUnaryOperator() || Tok.Next->isOneOf(tok::amp, tok::star);
1138 if (!NextIsUnary || Tok.Next->is(tok::plus) ||
1139 !Tok.Next->Next->isOneOf(tok::identifier, tok::numeric_constant))
1140 return false;
1141 // Search for unexpected tokens.
1142 for (FormatToken *Prev = Tok.Previous; Prev != Tok.MatchingParen;
1143 Prev = Prev->Previous) {
1144 if (!Prev->isOneOf(tok::kw_const, tok::identifier, tok::coloncolon))
1145 return false;
1146 }
1147 return true;
1148 }
1149
1150 /// \brief Return the type of the given token assuming it is * or &.
determineStarAmpUsage(const FormatToken & Tok,bool IsExpression,bool InTemplateArgument)1151 TokenType determineStarAmpUsage(const FormatToken &Tok, bool IsExpression,
1152 bool InTemplateArgument) {
1153 if (Style.Language == FormatStyle::LK_JavaScript)
1154 return TT_BinaryOperator;
1155
1156 const FormatToken *PrevToken = Tok.getPreviousNonComment();
1157 if (!PrevToken)
1158 return TT_UnaryOperator;
1159
1160 const FormatToken *NextToken = Tok.getNextNonComment();
1161 if (!NextToken ||
1162 NextToken->isOneOf(tok::arrow, Keywords.kw_final,
1163 Keywords.kw_override) ||
1164 (NextToken->is(tok::l_brace) && !NextToken->getNextNonComment()))
1165 return TT_PointerOrReference;
1166
1167 if (PrevToken->is(tok::coloncolon))
1168 return TT_PointerOrReference;
1169
1170 if (PrevToken->isOneOf(tok::l_paren, tok::l_square, tok::l_brace,
1171 tok::comma, tok::semi, tok::kw_return, tok::colon,
1172 tok::equal, tok::kw_delete, tok::kw_sizeof) ||
1173 PrevToken->isOneOf(TT_BinaryOperator, TT_ConditionalExpr,
1174 TT_UnaryOperator, TT_CastRParen))
1175 return TT_UnaryOperator;
1176
1177 if (NextToken->is(tok::l_square) && NextToken->isNot(TT_LambdaLSquare))
1178 return TT_PointerOrReference;
1179 if (NextToken->is(tok::kw_operator) && !IsExpression)
1180 return TT_PointerOrReference;
1181 if (NextToken->isOneOf(tok::comma, tok::semi))
1182 return TT_PointerOrReference;
1183
1184 if (PrevToken->is(tok::r_paren) && PrevToken->MatchingParen &&
1185 PrevToken->MatchingParen->Previous &&
1186 PrevToken->MatchingParen->Previous->isOneOf(tok::kw_typeof,
1187 tok::kw_decltype))
1188 return TT_PointerOrReference;
1189
1190 if (PrevToken->Tok.isLiteral() ||
1191 PrevToken->isOneOf(tok::r_paren, tok::r_square, tok::kw_true,
1192 tok::kw_false, tok::r_brace) ||
1193 NextToken->Tok.isLiteral() ||
1194 NextToken->isOneOf(tok::kw_true, tok::kw_false) ||
1195 NextToken->isUnaryOperator() ||
1196 // If we know we're in a template argument, there are no named
1197 // declarations. Thus, having an identifier on the right-hand side
1198 // indicates a binary operator.
1199 (InTemplateArgument && NextToken->Tok.isAnyIdentifier()))
1200 return TT_BinaryOperator;
1201
1202 // "&&(" is quite unlikely to be two successive unary "&".
1203 if (Tok.is(tok::ampamp) && NextToken && NextToken->is(tok::l_paren))
1204 return TT_BinaryOperator;
1205
1206 // This catches some cases where evaluation order is used as control flow:
1207 // aaa && aaa->f();
1208 const FormatToken *NextNextToken = NextToken->getNextNonComment();
1209 if (NextNextToken && NextNextToken->is(tok::arrow))
1210 return TT_BinaryOperator;
1211
1212 // It is very unlikely that we are going to find a pointer or reference type
1213 // definition on the RHS of an assignment.
1214 if (IsExpression && !Contexts.back().CaretFound)
1215 return TT_BinaryOperator;
1216
1217 return TT_PointerOrReference;
1218 }
1219
determinePlusMinusCaretUsage(const FormatToken & Tok)1220 TokenType determinePlusMinusCaretUsage(const FormatToken &Tok) {
1221 const FormatToken *PrevToken = Tok.getPreviousNonComment();
1222 if (!PrevToken || PrevToken->is(TT_CastRParen))
1223 return TT_UnaryOperator;
1224
1225 // Use heuristics to recognize unary operators.
1226 if (PrevToken->isOneOf(tok::equal, tok::l_paren, tok::comma, tok::l_square,
1227 tok::question, tok::colon, tok::kw_return,
1228 tok::kw_case, tok::at, tok::l_brace))
1229 return TT_UnaryOperator;
1230
1231 // There can't be two consecutive binary operators.
1232 if (PrevToken->is(TT_BinaryOperator))
1233 return TT_UnaryOperator;
1234
1235 // Fall back to marking the token as binary operator.
1236 return TT_BinaryOperator;
1237 }
1238
1239 /// \brief Determine whether ++/-- are pre- or post-increments/-decrements.
determineIncrementUsage(const FormatToken & Tok)1240 TokenType determineIncrementUsage(const FormatToken &Tok) {
1241 const FormatToken *PrevToken = Tok.getPreviousNonComment();
1242 if (!PrevToken || PrevToken->is(TT_CastRParen))
1243 return TT_UnaryOperator;
1244 if (PrevToken->isOneOf(tok::r_paren, tok::r_square, tok::identifier))
1245 return TT_TrailingUnaryOperator;
1246
1247 return TT_UnaryOperator;
1248 }
1249
1250 SmallVector<Context, 8> Contexts;
1251
1252 const FormatStyle &Style;
1253 AnnotatedLine &Line;
1254 FormatToken *CurrentToken;
1255 bool AutoFound;
1256 const AdditionalKeywords &Keywords;
1257
1258 // Set of "<" tokens that do not open a template parameter list. If parseAngle
1259 // determines that a specific token can't be a template opener, it will make
1260 // same decision irrespective of the decisions for tokens leading up to it.
1261 // Store this information to prevent this from causing exponential runtime.
1262 llvm::SmallPtrSet<FormatToken *, 16> NonTemplateLess;
1263 };
1264
1265 static const int PrecedenceUnaryOperator = prec::PointerToMember + 1;
1266 static const int PrecedenceArrowAndPeriod = prec::PointerToMember + 2;
1267
1268 /// \brief Parses binary expressions by inserting fake parenthesis based on
1269 /// operator precedence.
1270 class ExpressionParser {
1271 public:
ExpressionParser(const FormatStyle & Style,const AdditionalKeywords & Keywords,AnnotatedLine & Line)1272 ExpressionParser(const FormatStyle &Style, const AdditionalKeywords &Keywords,
1273 AnnotatedLine &Line)
1274 : Style(Style), Keywords(Keywords), Current(Line.First) {}
1275
1276 /// \brief Parse expressions with the given operatore precedence.
parse(int Precedence=0)1277 void parse(int Precedence = 0) {
1278 // Skip 'return' and ObjC selector colons as they are not part of a binary
1279 // expression.
1280 while (Current && (Current->is(tok::kw_return) ||
1281 (Current->is(tok::colon) &&
1282 Current->isOneOf(TT_ObjCMethodExpr, TT_DictLiteral))))
1283 next();
1284
1285 if (!Current || Precedence > PrecedenceArrowAndPeriod)
1286 return;
1287
1288 // Conditional expressions need to be parsed separately for proper nesting.
1289 if (Precedence == prec::Conditional) {
1290 parseConditionalExpr();
1291 return;
1292 }
1293
1294 // Parse unary operators, which all have a higher precedence than binary
1295 // operators.
1296 if (Precedence == PrecedenceUnaryOperator) {
1297 parseUnaryOperator();
1298 return;
1299 }
1300
1301 FormatToken *Start = Current;
1302 FormatToken *LatestOperator = nullptr;
1303 unsigned OperatorIndex = 0;
1304
1305 while (Current) {
1306 // Consume operators with higher precedence.
1307 parse(Precedence + 1);
1308
1309 int CurrentPrecedence = getCurrentPrecedence();
1310
1311 if (Current && Current->is(TT_SelectorName) &&
1312 Precedence == CurrentPrecedence) {
1313 if (LatestOperator)
1314 addFakeParenthesis(Start, prec::Level(Precedence));
1315 Start = Current;
1316 }
1317
1318 // At the end of the line or when an operator with higher precedence is
1319 // found, insert fake parenthesis and return.
1320 if (!Current || (Current->closesScope() && Current->MatchingParen) ||
1321 (CurrentPrecedence != -1 && CurrentPrecedence < Precedence) ||
1322 (CurrentPrecedence == prec::Conditional &&
1323 Precedence == prec::Assignment && Current->is(tok::colon))) {
1324 break;
1325 }
1326
1327 // Consume scopes: (), [], <> and {}
1328 if (Current->opensScope()) {
1329 while (Current && !Current->closesScope()) {
1330 next();
1331 parse();
1332 }
1333 next();
1334 } else {
1335 // Operator found.
1336 if (CurrentPrecedence == Precedence) {
1337 LatestOperator = Current;
1338 Current->OperatorIndex = OperatorIndex;
1339 ++OperatorIndex;
1340 }
1341 next(/*SkipPastLeadingComments=*/Precedence > 0);
1342 }
1343 }
1344
1345 if (LatestOperator && (Current || Precedence > 0)) {
1346 LatestOperator->LastOperator = true;
1347 if (Precedence == PrecedenceArrowAndPeriod) {
1348 // Call expressions don't have a binary operator precedence.
1349 addFakeParenthesis(Start, prec::Unknown);
1350 } else {
1351 addFakeParenthesis(Start, prec::Level(Precedence));
1352 }
1353 }
1354 }
1355
1356 private:
1357 /// \brief Gets the precedence (+1) of the given token for binary operators
1358 /// and other tokens that we treat like binary operators.
getCurrentPrecedence()1359 int getCurrentPrecedence() {
1360 if (Current) {
1361 const FormatToken *NextNonComment = Current->getNextNonComment();
1362 if (Current->is(TT_ConditionalExpr))
1363 return prec::Conditional;
1364 if (NextNonComment && NextNonComment->is(tok::colon) &&
1365 NextNonComment->is(TT_DictLiteral))
1366 return prec::Comma;
1367 if (Current->is(TT_LambdaArrow))
1368 return prec::Comma;
1369 if (Current->is(TT_JsFatArrow))
1370 return prec::Assignment;
1371 if (Current->isOneOf(tok::semi, TT_InlineASMColon, TT_SelectorName,
1372 TT_JsComputedPropertyName) ||
1373 (Current->is(tok::comment) && NextNonComment &&
1374 NextNonComment->is(TT_SelectorName)))
1375 return 0;
1376 if (Current->is(TT_RangeBasedForLoopColon))
1377 return prec::Comma;
1378 if ((Style.Language == FormatStyle::LK_Java ||
1379 Style.Language == FormatStyle::LK_JavaScript) &&
1380 Current->is(Keywords.kw_instanceof))
1381 return prec::Relational;
1382 if (Current->is(TT_BinaryOperator) || Current->is(tok::comma))
1383 return Current->getPrecedence();
1384 if (Current->isOneOf(tok::period, tok::arrow))
1385 return PrecedenceArrowAndPeriod;
1386 if (Style.Language == FormatStyle::LK_Java &&
1387 Current->isOneOf(Keywords.kw_extends, Keywords.kw_implements,
1388 Keywords.kw_throws))
1389 return 0;
1390 }
1391 return -1;
1392 }
1393
addFakeParenthesis(FormatToken * Start,prec::Level Precedence)1394 void addFakeParenthesis(FormatToken *Start, prec::Level Precedence) {
1395 Start->FakeLParens.push_back(Precedence);
1396 if (Precedence > prec::Unknown)
1397 Start->StartsBinaryExpression = true;
1398 if (Current) {
1399 FormatToken *Previous = Current->Previous;
1400 while (Previous->is(tok::comment) && Previous->Previous)
1401 Previous = Previous->Previous;
1402 ++Previous->FakeRParens;
1403 if (Precedence > prec::Unknown)
1404 Previous->EndsBinaryExpression = true;
1405 }
1406 }
1407
1408 /// \brief Parse unary operator expressions and surround them with fake
1409 /// parentheses if appropriate.
parseUnaryOperator()1410 void parseUnaryOperator() {
1411 if (!Current || Current->isNot(TT_UnaryOperator)) {
1412 parse(PrecedenceArrowAndPeriod);
1413 return;
1414 }
1415
1416 FormatToken *Start = Current;
1417 next();
1418 parseUnaryOperator();
1419
1420 // The actual precedence doesn't matter.
1421 addFakeParenthesis(Start, prec::Unknown);
1422 }
1423
parseConditionalExpr()1424 void parseConditionalExpr() {
1425 while (Current && Current->isTrailingComment()) {
1426 next();
1427 }
1428 FormatToken *Start = Current;
1429 parse(prec::LogicalOr);
1430 if (!Current || !Current->is(tok::question))
1431 return;
1432 next();
1433 parse(prec::Assignment);
1434 if (!Current || Current->isNot(TT_ConditionalExpr))
1435 return;
1436 next();
1437 parse(prec::Assignment);
1438 addFakeParenthesis(Start, prec::Conditional);
1439 }
1440
next(bool SkipPastLeadingComments=true)1441 void next(bool SkipPastLeadingComments = true) {
1442 if (Current)
1443 Current = Current->Next;
1444 while (Current &&
1445 (Current->NewlinesBefore == 0 || SkipPastLeadingComments) &&
1446 Current->isTrailingComment())
1447 Current = Current->Next;
1448 }
1449
1450 const FormatStyle &Style;
1451 const AdditionalKeywords &Keywords;
1452 FormatToken *Current;
1453 };
1454
1455 } // end anonymous namespace
1456
setCommentLineLevels(SmallVectorImpl<AnnotatedLine * > & Lines)1457 void TokenAnnotator::setCommentLineLevels(
1458 SmallVectorImpl<AnnotatedLine *> &Lines) {
1459 const AnnotatedLine *NextNonCommentLine = nullptr;
1460 for (SmallVectorImpl<AnnotatedLine *>::reverse_iterator I = Lines.rbegin(),
1461 E = Lines.rend();
1462 I != E; ++I) {
1463 if (NextNonCommentLine && (*I)->First->is(tok::comment) &&
1464 (*I)->First->Next == nullptr)
1465 (*I)->Level = NextNonCommentLine->Level;
1466 else
1467 NextNonCommentLine = (*I)->First->isNot(tok::r_brace) ? (*I) : nullptr;
1468
1469 setCommentLineLevels((*I)->Children);
1470 }
1471 }
1472
annotate(AnnotatedLine & Line)1473 void TokenAnnotator::annotate(AnnotatedLine &Line) {
1474 for (SmallVectorImpl<AnnotatedLine *>::iterator I = Line.Children.begin(),
1475 E = Line.Children.end();
1476 I != E; ++I) {
1477 annotate(**I);
1478 }
1479 AnnotatingParser Parser(Style, Line, Keywords);
1480 Line.Type = Parser.parseLine();
1481 if (Line.Type == LT_Invalid)
1482 return;
1483
1484 ExpressionParser ExprParser(Style, Keywords, Line);
1485 ExprParser.parse();
1486
1487 if (Line.startsWith(TT_ObjCMethodSpecifier))
1488 Line.Type = LT_ObjCMethodDecl;
1489 else if (Line.startsWith(TT_ObjCDecl))
1490 Line.Type = LT_ObjCDecl;
1491 else if (Line.startsWith(TT_ObjCProperty))
1492 Line.Type = LT_ObjCProperty;
1493
1494 Line.First->SpacesRequiredBefore = 1;
1495 Line.First->CanBreakBefore = Line.First->MustBreakBefore;
1496 }
1497
1498 // This function heuristically determines whether 'Current' starts the name of a
1499 // function declaration.
isFunctionDeclarationName(const FormatToken & Current)1500 static bool isFunctionDeclarationName(const FormatToken &Current) {
1501 auto skipOperatorName = [](const FormatToken* Next) -> const FormatToken* {
1502 for (; Next; Next = Next->Next) {
1503 if (Next->is(TT_OverloadedOperatorLParen))
1504 return Next;
1505 if (Next->is(TT_OverloadedOperator))
1506 continue;
1507 if (Next->isOneOf(tok::kw_new, tok::kw_delete)) {
1508 // For 'new[]' and 'delete[]'.
1509 if (Next->Next && Next->Next->is(tok::l_square) &&
1510 Next->Next->Next && Next->Next->Next->is(tok::r_square))
1511 Next = Next->Next->Next;
1512 continue;
1513 }
1514
1515 break;
1516 }
1517 return nullptr;
1518 };
1519
1520 const FormatToken *Next = Current.Next;
1521 if (Current.is(tok::kw_operator)) {
1522 if (Current.Previous && Current.Previous->is(tok::coloncolon))
1523 return false;
1524 Next = skipOperatorName(Next);
1525 } else {
1526 if (!Current.is(TT_StartOfName) || Current.NestingLevel != 0)
1527 return false;
1528 for (; Next; Next = Next->Next) {
1529 if (Next->is(TT_TemplateOpener)) {
1530 Next = Next->MatchingParen;
1531 } else if (Next->is(tok::coloncolon)) {
1532 Next = Next->Next;
1533 if (!Next)
1534 return false;
1535 if (Next->is(tok::kw_operator)) {
1536 Next = skipOperatorName(Next->Next);
1537 break;
1538 }
1539 if (!Next->is(tok::identifier))
1540 return false;
1541 } else if (Next->is(tok::l_paren)) {
1542 break;
1543 } else {
1544 return false;
1545 }
1546 }
1547 }
1548
1549 if (!Next || !Next->is(tok::l_paren))
1550 return false;
1551 if (Next->Next == Next->MatchingParen)
1552 return true;
1553 for (const FormatToken *Tok = Next->Next; Tok && Tok != Next->MatchingParen;
1554 Tok = Tok->Next) {
1555 if (Tok->is(tok::kw_const) || Tok->isSimpleTypeSpecifier() ||
1556 Tok->isOneOf(TT_PointerOrReference, TT_StartOfName))
1557 return true;
1558 if (Tok->isOneOf(tok::l_brace, tok::string_literal, TT_ObjCMethodExpr) ||
1559 Tok->Tok.isLiteral())
1560 return false;
1561 }
1562 return false;
1563 }
1564
mustBreakForReturnType(const AnnotatedLine & Line) const1565 bool TokenAnnotator::mustBreakForReturnType(const AnnotatedLine &Line) const {
1566 assert(Line.MightBeFunctionDecl);
1567
1568 if ((Style.AlwaysBreakAfterReturnType == FormatStyle::RTBS_TopLevel ||
1569 Style.AlwaysBreakAfterReturnType ==
1570 FormatStyle::RTBS_TopLevelDefinitions) &&
1571 Line.Level > 0)
1572 return false;
1573
1574 switch (Style.AlwaysBreakAfterReturnType) {
1575 case FormatStyle::RTBS_None:
1576 return false;
1577 case FormatStyle::RTBS_All:
1578 case FormatStyle::RTBS_TopLevel:
1579 return true;
1580 case FormatStyle::RTBS_AllDefinitions:
1581 case FormatStyle::RTBS_TopLevelDefinitions:
1582 return Line.mightBeFunctionDefinition();
1583 }
1584
1585 return false;
1586 }
1587
calculateFormattingInformation(AnnotatedLine & Line)1588 void TokenAnnotator::calculateFormattingInformation(AnnotatedLine &Line) {
1589 for (SmallVectorImpl<AnnotatedLine *>::iterator I = Line.Children.begin(),
1590 E = Line.Children.end();
1591 I != E; ++I) {
1592 calculateFormattingInformation(**I);
1593 }
1594
1595 Line.First->TotalLength =
1596 Line.First->IsMultiline ? Style.ColumnLimit : Line.First->ColumnWidth;
1597 if (!Line.First->Next)
1598 return;
1599 FormatToken *Current = Line.First->Next;
1600 bool InFunctionDecl = Line.MightBeFunctionDecl;
1601 while (Current) {
1602 if (isFunctionDeclarationName(*Current))
1603 Current->Type = TT_FunctionDeclarationName;
1604 if (Current->is(TT_LineComment)) {
1605 if (Current->Previous->BlockKind == BK_BracedInit &&
1606 Current->Previous->opensScope())
1607 Current->SpacesRequiredBefore = Style.Cpp11BracedListStyle ? 0 : 1;
1608 else
1609 Current->SpacesRequiredBefore = Style.SpacesBeforeTrailingComments;
1610
1611 // If we find a trailing comment, iterate backwards to determine whether
1612 // it seems to relate to a specific parameter. If so, break before that
1613 // parameter to avoid changing the comment's meaning. E.g. don't move 'b'
1614 // to the previous line in:
1615 // SomeFunction(a,
1616 // b, // comment
1617 // c);
1618 if (!Current->HasUnescapedNewline) {
1619 for (FormatToken *Parameter = Current->Previous; Parameter;
1620 Parameter = Parameter->Previous) {
1621 if (Parameter->isOneOf(tok::comment, tok::r_brace))
1622 break;
1623 if (Parameter->Previous && Parameter->Previous->is(tok::comma)) {
1624 if (!Parameter->Previous->is(TT_CtorInitializerComma) &&
1625 Parameter->HasUnescapedNewline)
1626 Parameter->MustBreakBefore = true;
1627 break;
1628 }
1629 }
1630 }
1631 } else if (Current->SpacesRequiredBefore == 0 &&
1632 spaceRequiredBefore(Line, *Current)) {
1633 Current->SpacesRequiredBefore = 1;
1634 }
1635
1636 Current->MustBreakBefore =
1637 Current->MustBreakBefore || mustBreakBefore(Line, *Current);
1638
1639 if (!Current->MustBreakBefore && InFunctionDecl &&
1640 Current->is(TT_FunctionDeclarationName))
1641 Current->MustBreakBefore = mustBreakForReturnType(Line);
1642
1643 Current->CanBreakBefore =
1644 Current->MustBreakBefore || canBreakBefore(Line, *Current);
1645 unsigned ChildSize = 0;
1646 if (Current->Previous->Children.size() == 1) {
1647 FormatToken &LastOfChild = *Current->Previous->Children[0]->Last;
1648 ChildSize = LastOfChild.isTrailingComment() ? Style.ColumnLimit
1649 : LastOfChild.TotalLength + 1;
1650 }
1651 const FormatToken *Prev = Current->Previous;
1652 if (Current->MustBreakBefore || Prev->Children.size() > 1 ||
1653 (Prev->Children.size() == 1 &&
1654 Prev->Children[0]->First->MustBreakBefore) ||
1655 Current->IsMultiline)
1656 Current->TotalLength = Prev->TotalLength + Style.ColumnLimit;
1657 else
1658 Current->TotalLength = Prev->TotalLength + Current->ColumnWidth +
1659 ChildSize + Current->SpacesRequiredBefore;
1660
1661 if (Current->is(TT_CtorInitializerColon))
1662 InFunctionDecl = false;
1663
1664 // FIXME: Only calculate this if CanBreakBefore is true once static
1665 // initializers etc. are sorted out.
1666 // FIXME: Move magic numbers to a better place.
1667 Current->SplitPenalty = 20 * Current->BindingStrength +
1668 splitPenalty(Line, *Current, InFunctionDecl);
1669
1670 Current = Current->Next;
1671 }
1672
1673 calculateUnbreakableTailLengths(Line);
1674 for (Current = Line.First; Current != nullptr; Current = Current->Next) {
1675 if (Current->Role)
1676 Current->Role->precomputeFormattingInfos(Current);
1677 }
1678
1679 DEBUG({ printDebugInfo(Line); });
1680 }
1681
calculateUnbreakableTailLengths(AnnotatedLine & Line)1682 void TokenAnnotator::calculateUnbreakableTailLengths(AnnotatedLine &Line) {
1683 unsigned UnbreakableTailLength = 0;
1684 FormatToken *Current = Line.Last;
1685 while (Current) {
1686 Current->UnbreakableTailLength = UnbreakableTailLength;
1687 if (Current->CanBreakBefore ||
1688 Current->isOneOf(tok::comment, tok::string_literal)) {
1689 UnbreakableTailLength = 0;
1690 } else {
1691 UnbreakableTailLength +=
1692 Current->ColumnWidth + Current->SpacesRequiredBefore;
1693 }
1694 Current = Current->Previous;
1695 }
1696 }
1697
splitPenalty(const AnnotatedLine & Line,const FormatToken & Tok,bool InFunctionDecl)1698 unsigned TokenAnnotator::splitPenalty(const AnnotatedLine &Line,
1699 const FormatToken &Tok,
1700 bool InFunctionDecl) {
1701 const FormatToken &Left = *Tok.Previous;
1702 const FormatToken &Right = Tok;
1703
1704 if (Left.is(tok::semi))
1705 return 0;
1706
1707 if (Style.Language == FormatStyle::LK_Java) {
1708 if (Right.isOneOf(Keywords.kw_extends, Keywords.kw_throws))
1709 return 1;
1710 if (Right.is(Keywords.kw_implements))
1711 return 2;
1712 if (Left.is(tok::comma) && Left.NestingLevel == 0)
1713 return 3;
1714 } else if (Style.Language == FormatStyle::LK_JavaScript) {
1715 if (Right.is(Keywords.kw_function) && Left.isNot(tok::comma))
1716 return 100;
1717 if (Left.is(TT_JsTypeColon))
1718 return 100;
1719 }
1720
1721 if (Left.is(tok::comma) || (Right.is(tok::identifier) && Right.Next &&
1722 Right.Next->is(TT_DictLiteral)))
1723 return 1;
1724 if (Right.is(tok::l_square)) {
1725 if (Style.Language == FormatStyle::LK_Proto)
1726 return 1;
1727 // Slightly prefer formatting local lambda definitions like functions.
1728 if (Right.is(TT_LambdaLSquare) && Left.is(tok::equal))
1729 return 50;
1730 if (!Right.isOneOf(TT_ObjCMethodExpr, TT_LambdaLSquare,
1731 TT_ArrayInitializerLSquare))
1732 return 500;
1733 }
1734
1735 if (Right.isOneOf(TT_StartOfName, TT_FunctionDeclarationName) ||
1736 Right.is(tok::kw_operator)) {
1737 if (Line.startsWith(tok::kw_for) && Right.PartOfMultiVariableDeclStmt)
1738 return 3;
1739 if (Left.is(TT_StartOfName))
1740 return 110;
1741 if (InFunctionDecl && Right.NestingLevel == 0)
1742 return Style.PenaltyReturnTypeOnItsOwnLine;
1743 return 200;
1744 }
1745 if (Right.is(TT_PointerOrReference))
1746 return 190;
1747 if (Right.is(TT_LambdaArrow))
1748 return 110;
1749 if (Left.is(tok::equal) && Right.is(tok::l_brace))
1750 return 150;
1751 if (Left.is(TT_CastRParen))
1752 return 100;
1753 if (Left.is(tok::coloncolon) ||
1754 (Right.is(tok::period) && Style.Language == FormatStyle::LK_Proto))
1755 return 500;
1756 if (Left.isOneOf(tok::kw_class, tok::kw_struct))
1757 return 5000;
1758
1759 if (Left.isOneOf(TT_RangeBasedForLoopColon, TT_InheritanceColon))
1760 return 2;
1761
1762 if (Right.isMemberAccess()) {
1763 // Breaking before the "./->" of a chained call/member access is reasonably
1764 // cheap, as formatting those with one call per line is generally
1765 // desirable. In particular, it should be cheaper to break before the call
1766 // than it is to break inside a call's parameters, which could lead to weird
1767 // "hanging" indents. The exception is the very last "./->" to support this
1768 // frequent pattern:
1769 //
1770 // aaaaaaaa.aaaaaaaa.bbbbbbb().ccccccccccccccccccccc(
1771 // dddddddd);
1772 //
1773 // which might otherwise be blown up onto many lines. Here, clang-format
1774 // won't produce "hanging" indents anyway as there is no other trailing
1775 // call.
1776 return Right.LastOperator ? 150 : 40;
1777 }
1778
1779 if (Right.is(TT_TrailingAnnotation) &&
1780 (!Right.Next || Right.Next->isNot(tok::l_paren))) {
1781 // Moving trailing annotations to the next line is fine for ObjC method
1782 // declarations.
1783 if (Line.startsWith(TT_ObjCMethodSpecifier))
1784 return 10;
1785 // Generally, breaking before a trailing annotation is bad unless it is
1786 // function-like. It seems to be especially preferable to keep standard
1787 // annotations (i.e. "const", "final" and "override") on the same line.
1788 // Use a slightly higher penalty after ")" so that annotations like
1789 // "const override" are kept together.
1790 bool is_short_annotation = Right.TokenText.size() < 10;
1791 return (Left.is(tok::r_paren) ? 100 : 120) + (is_short_annotation ? 50 : 0);
1792 }
1793
1794 // In for-loops, prefer breaking at ',' and ';'.
1795 if (Line.startsWith(tok::kw_for) && Left.is(tok::equal))
1796 return 4;
1797
1798 // In Objective-C method expressions, prefer breaking before "param:" over
1799 // breaking after it.
1800 if (Right.is(TT_SelectorName))
1801 return 0;
1802 if (Left.is(tok::colon) && Left.is(TT_ObjCMethodExpr))
1803 return Line.MightBeFunctionDecl ? 50 : 500;
1804
1805 if (Left.is(tok::l_paren) && InFunctionDecl &&
1806 Style.AlignAfterOpenBracket != FormatStyle::BAS_DontAlign)
1807 return 100;
1808 if (Left.is(tok::l_paren) && Left.Previous &&
1809 Left.Previous->isOneOf(tok::kw_if, tok::kw_for))
1810 return 1000;
1811 if (Left.is(tok::equal) && InFunctionDecl)
1812 return 110;
1813 if (Right.is(tok::r_brace))
1814 return 1;
1815 if (Left.is(TT_TemplateOpener))
1816 return 100;
1817 if (Left.opensScope()) {
1818 if (Style.AlignAfterOpenBracket == FormatStyle::BAS_DontAlign)
1819 return 0;
1820 return Left.ParameterCount > 1 ? Style.PenaltyBreakBeforeFirstCallParameter
1821 : 19;
1822 }
1823 if (Left.is(TT_JavaAnnotation))
1824 return 50;
1825
1826 if (Right.is(tok::lessless)) {
1827 if (Left.is(tok::string_literal) &&
1828 (!Right.LastOperator || Right.OperatorIndex != 1)) {
1829 StringRef Content = Left.TokenText;
1830 if (Content.startswith("\""))
1831 Content = Content.drop_front(1);
1832 if (Content.endswith("\""))
1833 Content = Content.drop_back(1);
1834 Content = Content.trim();
1835 if (Content.size() > 1 &&
1836 (Content.back() == ':' || Content.back() == '='))
1837 return 25;
1838 }
1839 return 1; // Breaking at a << is really cheap.
1840 }
1841 if (Left.is(TT_ConditionalExpr))
1842 return prec::Conditional;
1843 prec::Level Level = Left.getPrecedence();
1844 if (Level != prec::Unknown)
1845 return Level;
1846 Level = Right.getPrecedence();
1847 if (Level != prec::Unknown)
1848 return Level;
1849
1850 return 3;
1851 }
1852
spaceRequiredBetween(const AnnotatedLine & Line,const FormatToken & Left,const FormatToken & Right)1853 bool TokenAnnotator::spaceRequiredBetween(const AnnotatedLine &Line,
1854 const FormatToken &Left,
1855 const FormatToken &Right) {
1856 if (Left.is(tok::kw_return) && Right.isNot(tok::semi))
1857 return true;
1858 if (Style.ObjCSpaceAfterProperty && Line.Type == LT_ObjCProperty &&
1859 Left.Tok.getObjCKeywordID() == tok::objc_property)
1860 return true;
1861 if (Right.is(tok::hashhash))
1862 return Left.is(tok::hash);
1863 if (Left.isOneOf(tok::hashhash, tok::hash))
1864 return Right.is(tok::hash);
1865 if (Left.is(tok::l_paren) && Right.is(tok::r_paren))
1866 return Style.SpaceInEmptyParentheses;
1867 if (Left.is(tok::l_paren) || Right.is(tok::r_paren))
1868 return (Right.is(TT_CastRParen) ||
1869 (Left.MatchingParen && Left.MatchingParen->is(TT_CastRParen)))
1870 ? Style.SpacesInCStyleCastParentheses
1871 : Style.SpacesInParentheses;
1872 if (Right.isOneOf(tok::semi, tok::comma))
1873 return false;
1874 if (Right.is(tok::less) &&
1875 (Left.is(tok::kw_template) ||
1876 (Line.Type == LT_ObjCDecl && Style.ObjCSpaceBeforeProtocolList)))
1877 return true;
1878 if (Left.isOneOf(tok::exclaim, tok::tilde))
1879 return false;
1880 if (Left.is(tok::at) &&
1881 Right.isOneOf(tok::identifier, tok::string_literal, tok::char_constant,
1882 tok::numeric_constant, tok::l_paren, tok::l_brace,
1883 tok::kw_true, tok::kw_false))
1884 return false;
1885 if (Left.is(tok::coloncolon))
1886 return false;
1887 if (Left.is(tok::less) || Right.isOneOf(tok::greater, tok::less))
1888 return false;
1889 if (Right.is(tok::ellipsis))
1890 return Left.Tok.isLiteral();
1891 if (Left.is(tok::l_square) && Right.is(tok::amp))
1892 return false;
1893 if (Right.is(TT_PointerOrReference))
1894 return (Left.is(tok::r_paren) && Left.MatchingParen &&
1895 (Left.MatchingParen->is(TT_OverloadedOperatorLParen) ||
1896 (Left.MatchingParen->Previous &&
1897 Left.MatchingParen->Previous->is(TT_FunctionDeclarationName)))) ||
1898 (Left.Tok.isLiteral() ||
1899 (!Left.isOneOf(TT_PointerOrReference, tok::l_paren) &&
1900 (Style.PointerAlignment != FormatStyle::PAS_Left ||
1901 Line.IsMultiVariableDeclStmt)));
1902 if (Right.is(TT_FunctionTypeLParen) && Left.isNot(tok::l_paren) &&
1903 (!Left.is(TT_PointerOrReference) ||
1904 (Style.PointerAlignment != FormatStyle::PAS_Right &&
1905 !Line.IsMultiVariableDeclStmt)))
1906 return true;
1907 if (Left.is(TT_PointerOrReference))
1908 return Right.Tok.isLiteral() ||
1909 Right.isOneOf(TT_BlockComment, Keywords.kw_final,
1910 Keywords.kw_override) ||
1911 (Right.is(tok::l_brace) && Right.BlockKind == BK_Block) ||
1912 (!Right.isOneOf(TT_PointerOrReference, TT_ArraySubscriptLSquare,
1913 tok::l_paren) &&
1914 (Style.PointerAlignment != FormatStyle::PAS_Right &&
1915 !Line.IsMultiVariableDeclStmt) &&
1916 Left.Previous &&
1917 !Left.Previous->isOneOf(tok::l_paren, tok::coloncolon));
1918 if (Right.is(tok::star) && Left.is(tok::l_paren))
1919 return false;
1920 if (Left.is(tok::l_square))
1921 return (Left.is(TT_ArrayInitializerLSquare) &&
1922 Style.SpacesInContainerLiterals && Right.isNot(tok::r_square)) ||
1923 (Left.is(TT_ArraySubscriptLSquare) && Style.SpacesInSquareBrackets &&
1924 Right.isNot(tok::r_square));
1925 if (Right.is(tok::r_square))
1926 return Right.MatchingParen &&
1927 ((Style.SpacesInContainerLiterals &&
1928 Right.MatchingParen->is(TT_ArrayInitializerLSquare)) ||
1929 (Style.SpacesInSquareBrackets &&
1930 Right.MatchingParen->is(TT_ArraySubscriptLSquare)));
1931 if (Right.is(tok::l_square) &&
1932 !Right.isOneOf(TT_ObjCMethodExpr, TT_LambdaLSquare) &&
1933 !Left.isOneOf(tok::numeric_constant, TT_DictLiteral))
1934 return false;
1935 if (Left.is(tok::colon))
1936 return !Left.is(TT_ObjCMethodExpr);
1937 if (Left.is(tok::l_brace) && Right.is(tok::r_brace))
1938 return !Left.Children.empty(); // No spaces in "{}".
1939 if ((Left.is(tok::l_brace) && Left.BlockKind != BK_Block) ||
1940 (Right.is(tok::r_brace) && Right.MatchingParen &&
1941 Right.MatchingParen->BlockKind != BK_Block))
1942 return !Style.Cpp11BracedListStyle;
1943 if (Left.is(TT_BlockComment))
1944 return !Left.TokenText.endswith("=*/");
1945 if (Right.is(tok::l_paren)) {
1946 if (Left.is(tok::r_paren) && Left.is(TT_AttributeParen))
1947 return true;
1948 return Line.Type == LT_ObjCDecl || Left.is(tok::semi) ||
1949 (Style.SpaceBeforeParens != FormatStyle::SBPO_Never &&
1950 (Left.isOneOf(tok::kw_if, tok::pp_elif, tok::kw_for, tok::kw_while,
1951 tok::kw_switch, tok::kw_case, TT_ForEachMacro,
1952 TT_ObjCForIn) ||
1953 (Left.isOneOf(tok::kw_try, Keywords.kw___except, tok::kw_catch,
1954 tok::kw_new, tok::kw_delete) &&
1955 (!Left.Previous || Left.Previous->isNot(tok::period))))) ||
1956 (Style.SpaceBeforeParens == FormatStyle::SBPO_Always &&
1957 (Left.is(tok::identifier) || Left.isFunctionLikeKeyword() ||
1958 Left.is(tok::r_paren)) &&
1959 Line.Type != LT_PreprocessorDirective);
1960 }
1961 if (Left.is(tok::at) && Right.Tok.getObjCKeywordID() != tok::objc_not_keyword)
1962 return false;
1963 if (Right.is(TT_UnaryOperator))
1964 return !Left.isOneOf(tok::l_paren, tok::l_square, tok::at) &&
1965 (Left.isNot(tok::colon) || Left.isNot(TT_ObjCMethodExpr));
1966 if ((Left.isOneOf(tok::identifier, tok::greater, tok::r_square,
1967 tok::r_paren) ||
1968 Left.isSimpleTypeSpecifier()) &&
1969 Right.is(tok::l_brace) && Right.getNextNonComment() &&
1970 Right.BlockKind != BK_Block)
1971 return false;
1972 if (Left.is(tok::period) || Right.is(tok::period))
1973 return false;
1974 if (Right.is(tok::hash) && Left.is(tok::identifier) && Left.TokenText == "L")
1975 return false;
1976 if (Left.is(TT_TemplateCloser) && Left.MatchingParen &&
1977 Left.MatchingParen->Previous &&
1978 Left.MatchingParen->Previous->is(tok::period))
1979 // A.<B>DoSomething();
1980 return false;
1981 if (Left.is(TT_TemplateCloser) && Right.is(tok::l_square))
1982 return false;
1983 return true;
1984 }
1985
spaceRequiredBefore(const AnnotatedLine & Line,const FormatToken & Right)1986 bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
1987 const FormatToken &Right) {
1988 const FormatToken &Left = *Right.Previous;
1989 if (Right.Tok.getIdentifierInfo() && Left.Tok.getIdentifierInfo())
1990 return true; // Never ever merge two identifiers.
1991 if (Style.Language == FormatStyle::LK_Cpp) {
1992 if (Left.is(tok::kw_operator))
1993 return Right.is(tok::coloncolon);
1994 } else if (Style.Language == FormatStyle::LK_Proto) {
1995 if (Right.is(tok::period) &&
1996 Left.isOneOf(Keywords.kw_optional, Keywords.kw_required,
1997 Keywords.kw_repeated, Keywords.kw_extend))
1998 return true;
1999 if (Right.is(tok::l_paren) &&
2000 Left.isOneOf(Keywords.kw_returns, Keywords.kw_option))
2001 return true;
2002 } else if (Style.Language == FormatStyle::LK_JavaScript) {
2003 if (Left.isOneOf(Keywords.kw_let, Keywords.kw_var, TT_JsFatArrow,
2004 Keywords.kw_in))
2005 return true;
2006 if (Right.isOneOf(TT_JsTypeColon, TT_JsTypeOptionalQuestion))
2007 return false;
2008 if ((Left.is(tok::l_brace) || Right.is(tok::r_brace)) &&
2009 Line.First->isOneOf(Keywords.kw_import, tok::kw_export))
2010 return false;
2011 if (Left.is(tok::ellipsis))
2012 return false;
2013 if (Left.is(TT_TemplateCloser) &&
2014 !Right.isOneOf(tok::equal, tok::l_brace, tok::comma, tok::l_square,
2015 Keywords.kw_implements, Keywords.kw_extends))
2016 // Type assertions ('<type>expr') are not followed by whitespace. Other
2017 // locations that should have whitespace following are identified by the
2018 // above set of follower tokens.
2019 return false;
2020 } else if (Style.Language == FormatStyle::LK_Java) {
2021 if (Left.is(tok::r_square) && Right.is(tok::l_brace))
2022 return true;
2023 if (Left.is(Keywords.kw_synchronized) && Right.is(tok::l_paren))
2024 return Style.SpaceBeforeParens != FormatStyle::SBPO_Never;
2025 if ((Left.isOneOf(tok::kw_static, tok::kw_public, tok::kw_private,
2026 tok::kw_protected) ||
2027 Left.isOneOf(Keywords.kw_final, Keywords.kw_abstract,
2028 Keywords.kw_native)) &&
2029 Right.is(TT_TemplateOpener))
2030 return true;
2031 }
2032 if (Left.is(TT_ImplicitStringLiteral))
2033 return Right.WhitespaceRange.getBegin() != Right.WhitespaceRange.getEnd();
2034 if (Line.Type == LT_ObjCMethodDecl) {
2035 if (Left.is(TT_ObjCMethodSpecifier))
2036 return true;
2037 if (Left.is(tok::r_paren) && Right.is(tok::identifier))
2038 // Don't space between ')' and <id>
2039 return false;
2040 }
2041 if (Line.Type == LT_ObjCProperty &&
2042 (Right.is(tok::equal) || Left.is(tok::equal)))
2043 return false;
2044
2045 if (Right.isOneOf(TT_TrailingReturnArrow, TT_LambdaArrow) ||
2046 Left.isOneOf(TT_TrailingReturnArrow, TT_LambdaArrow))
2047 return true;
2048 if (Left.is(tok::comma))
2049 return true;
2050 if (Right.is(tok::comma))
2051 return false;
2052 if (Right.isOneOf(TT_CtorInitializerColon, TT_ObjCBlockLParen))
2053 return true;
2054 if (Right.is(TT_OverloadedOperatorLParen))
2055 return Style.SpaceBeforeParens == FormatStyle::SBPO_Always;
2056 if (Right.is(tok::colon)) {
2057 if (Line.First->isOneOf(tok::kw_case, tok::kw_default) ||
2058 !Right.getNextNonComment() || Right.getNextNonComment()->is(tok::semi))
2059 return false;
2060 if (Right.is(TT_ObjCMethodExpr))
2061 return false;
2062 if (Left.is(tok::question))
2063 return false;
2064 if (Right.is(TT_InlineASMColon) && Left.is(tok::coloncolon))
2065 return false;
2066 if (Right.is(TT_DictLiteral))
2067 return Style.SpacesInContainerLiterals;
2068 return true;
2069 }
2070 if (Left.is(TT_UnaryOperator))
2071 return Right.is(TT_BinaryOperator);
2072
2073 // If the next token is a binary operator or a selector name, we have
2074 // incorrectly classified the parenthesis as a cast. FIXME: Detect correctly.
2075 if (Left.is(TT_CastRParen))
2076 return Style.SpaceAfterCStyleCast ||
2077 Right.isOneOf(TT_BinaryOperator, TT_SelectorName);
2078
2079 if (Left.is(tok::greater) && Right.is(tok::greater))
2080 return Right.is(TT_TemplateCloser) && Left.is(TT_TemplateCloser) &&
2081 (Style.Standard != FormatStyle::LS_Cpp11 || Style.SpacesInAngles);
2082 if (Right.isOneOf(tok::arrow, tok::period, tok::arrowstar, tok::periodstar) ||
2083 Left.isOneOf(tok::arrow, tok::period, tok::arrowstar, tok::periodstar))
2084 return false;
2085 if (!Style.SpaceBeforeAssignmentOperators &&
2086 Right.getPrecedence() == prec::Assignment)
2087 return false;
2088 if (Right.is(tok::coloncolon) && Left.isNot(tok::l_brace))
2089 return (Left.is(TT_TemplateOpener) &&
2090 Style.Standard == FormatStyle::LS_Cpp03) ||
2091 !(Left.isOneOf(tok::identifier, tok::l_paren, tok::r_paren) ||
2092 Left.isOneOf(TT_TemplateCloser, TT_TemplateOpener));
2093 if ((Left.is(TT_TemplateOpener)) != (Right.is(TT_TemplateCloser)))
2094 return Style.SpacesInAngles;
2095 if ((Right.is(TT_BinaryOperator) && !Left.is(tok::l_paren)) ||
2096 (Left.isOneOf(TT_BinaryOperator, TT_ConditionalExpr) &&
2097 !Right.is(tok::r_paren)))
2098 return true;
2099 if (Left.is(TT_TemplateCloser) && Right.is(tok::l_paren) &&
2100 Right.isNot(TT_FunctionTypeLParen))
2101 return Style.SpaceBeforeParens == FormatStyle::SBPO_Always;
2102 if (Right.is(TT_TemplateOpener) && Left.is(tok::r_paren) &&
2103 Left.MatchingParen && Left.MatchingParen->is(TT_OverloadedOperatorLParen))
2104 return false;
2105 if (Right.is(tok::less) && Left.isNot(tok::l_paren) &&
2106 Line.startsWith(tok::hash))
2107 return true;
2108 if (Right.is(TT_TrailingUnaryOperator))
2109 return false;
2110 if (Left.is(TT_RegexLiteral))
2111 return false;
2112 return spaceRequiredBetween(Line, Left, Right);
2113 }
2114
2115 // Returns 'true' if 'Tok' is a brace we'd want to break before in Allman style.
isAllmanBrace(const FormatToken & Tok)2116 static bool isAllmanBrace(const FormatToken &Tok) {
2117 return Tok.is(tok::l_brace) && Tok.BlockKind == BK_Block &&
2118 !Tok.isOneOf(TT_ObjCBlockLBrace, TT_DictLiteral);
2119 }
2120
mustBreakBefore(const AnnotatedLine & Line,const FormatToken & Right)2121 bool TokenAnnotator::mustBreakBefore(const AnnotatedLine &Line,
2122 const FormatToken &Right) {
2123 const FormatToken &Left = *Right.Previous;
2124 if (Right.NewlinesBefore > 1 && Style.MaxEmptyLinesToKeep > 0)
2125 return true;
2126
2127 if (Style.Language == FormatStyle::LK_JavaScript) {
2128 // FIXME: This might apply to other languages and token kinds.
2129 if (Right.is(tok::char_constant) && Left.is(tok::plus) && Left.Previous &&
2130 Left.Previous->is(tok::char_constant))
2131 return true;
2132 if (Left.is(TT_DictLiteral) && Left.is(tok::l_brace) && Line.Level == 0 &&
2133 Left.Previous && Left.Previous->is(tok::equal) &&
2134 Line.First->isOneOf(tok::identifier, Keywords.kw_import, tok::kw_export,
2135 tok::kw_const) &&
2136 // kw_var/kw_let are pseudo-tokens that are tok::identifier, so match
2137 // above.
2138 !Line.First->isOneOf(Keywords.kw_var, Keywords.kw_let))
2139 // Object literals on the top level of a file are treated as "enum-style".
2140 // Each key/value pair is put on a separate line, instead of bin-packing.
2141 return true;
2142 if (Left.is(tok::l_brace) && Line.Level == 0 &&
2143 (Line.startsWith(tok::kw_enum) ||
2144 Line.startsWith(tok::kw_export, tok::kw_enum)))
2145 // JavaScript top-level enum key/value pairs are put on separate lines
2146 // instead of bin-packing.
2147 return true;
2148 if (Right.is(tok::r_brace) && Left.is(tok::l_brace) &&
2149 !Left.Children.empty())
2150 // Support AllowShortFunctionsOnASingleLine for JavaScript.
2151 return Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_None ||
2152 Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_Empty ||
2153 (Left.NestingLevel == 0 && Line.Level == 0 &&
2154 Style.AllowShortFunctionsOnASingleLine ==
2155 FormatStyle::SFS_Inline);
2156 } else if (Style.Language == FormatStyle::LK_Java) {
2157 if (Right.is(tok::plus) && Left.is(tok::string_literal) && Right.Next &&
2158 Right.Next->is(tok::string_literal))
2159 return true;
2160 }
2161
2162 // If the last token before a '}' is a comma or a trailing comment, the
2163 // intention is to insert a line break after it in order to make shuffling
2164 // around entries easier.
2165 const FormatToken *BeforeClosingBrace = nullptr;
2166 if (Left.isOneOf(tok::l_brace, TT_ArrayInitializerLSquare) &&
2167 Left.BlockKind != BK_Block && Left.MatchingParen)
2168 BeforeClosingBrace = Left.MatchingParen->Previous;
2169 else if (Right.MatchingParen &&
2170 Right.MatchingParen->isOneOf(tok::l_brace,
2171 TT_ArrayInitializerLSquare))
2172 BeforeClosingBrace = &Left;
2173 if (BeforeClosingBrace && (BeforeClosingBrace->is(tok::comma) ||
2174 BeforeClosingBrace->isTrailingComment()))
2175 return true;
2176
2177 if (Right.is(tok::comment))
2178 return Left.BlockKind != BK_BracedInit &&
2179 Left.isNot(TT_CtorInitializerColon) &&
2180 (Right.NewlinesBefore > 0 && Right.HasUnescapedNewline);
2181 if (Left.isTrailingComment())
2182 return true;
2183 if (Left.isStringLiteral() &&
2184 (Right.isStringLiteral() || Right.is(TT_ObjCStringLiteral)))
2185 return true;
2186 if (Right.Previous->IsUnterminatedLiteral)
2187 return true;
2188 if (Right.is(tok::lessless) && Right.Next &&
2189 Right.Previous->is(tok::string_literal) &&
2190 Right.Next->is(tok::string_literal))
2191 return true;
2192 if (Right.Previous->ClosesTemplateDeclaration &&
2193 Right.Previous->MatchingParen &&
2194 Right.Previous->MatchingParen->NestingLevel == 0 &&
2195 Style.AlwaysBreakTemplateDeclarations)
2196 return true;
2197 if ((Right.isOneOf(TT_CtorInitializerComma, TT_CtorInitializerColon)) &&
2198 Style.BreakConstructorInitializersBeforeComma &&
2199 !Style.ConstructorInitializerAllOnOneLineOrOnePerLine)
2200 return true;
2201 if (Right.is(tok::string_literal) && Right.TokenText.startswith("R\""))
2202 // Raw string literals are special wrt. line breaks. The author has made a
2203 // deliberate choice and might have aligned the contents of the string
2204 // literal accordingly. Thus, we try keep existing line breaks.
2205 return Right.NewlinesBefore > 0;
2206 if (Right.Previous->is(tok::l_brace) && Right.NestingLevel == 1 &&
2207 Style.Language == FormatStyle::LK_Proto)
2208 // Don't put enums onto single lines in protocol buffers.
2209 return true;
2210 if (Right.is(TT_InlineASMBrace))
2211 return Right.HasUnescapedNewline;
2212 if (isAllmanBrace(Left) || isAllmanBrace(Right))
2213 return (Line.startsWith(tok::kw_enum) && Style.BraceWrapping.AfterEnum) ||
2214 (Line.startsWith(tok::kw_class) && Style.BraceWrapping.AfterClass) ||
2215 (Line.startsWith(tok::kw_struct) && Style.BraceWrapping.AfterStruct);
2216 if (Style.Language == FormatStyle::LK_Proto && Left.isNot(tok::l_brace) &&
2217 Right.is(TT_SelectorName))
2218 return true;
2219 if (Left.is(TT_ObjCBlockLBrace) && !Style.AllowShortBlocksOnASingleLine)
2220 return true;
2221
2222 if ((Style.Language == FormatStyle::LK_Java ||
2223 Style.Language == FormatStyle::LK_JavaScript) &&
2224 Left.is(TT_LeadingJavaAnnotation) &&
2225 Right.isNot(TT_LeadingJavaAnnotation) && Right.isNot(tok::l_paren) &&
2226 (Line.Last->is(tok::l_brace) || Style.BreakAfterJavaFieldAnnotations))
2227 return true;
2228
2229 return false;
2230 }
2231
canBreakBefore(const AnnotatedLine & Line,const FormatToken & Right)2232 bool TokenAnnotator::canBreakBefore(const AnnotatedLine &Line,
2233 const FormatToken &Right) {
2234 const FormatToken &Left = *Right.Previous;
2235
2236 // Language-specific stuff.
2237 if (Style.Language == FormatStyle::LK_Java) {
2238 if (Left.isOneOf(Keywords.kw_throws, Keywords.kw_extends,
2239 Keywords.kw_implements))
2240 return false;
2241 if (Right.isOneOf(Keywords.kw_throws, Keywords.kw_extends,
2242 Keywords.kw_implements))
2243 return true;
2244 } else if (Style.Language == FormatStyle::LK_JavaScript) {
2245 if (Left.is(TT_JsFatArrow) && Right.is(tok::l_brace))
2246 return false;
2247 if (Left.is(TT_JsTypeColon))
2248 return true;
2249 }
2250
2251 if (Left.is(tok::at))
2252 return false;
2253 if (Left.Tok.getObjCKeywordID() == tok::objc_interface)
2254 return false;
2255 if (Left.isOneOf(TT_JavaAnnotation, TT_LeadingJavaAnnotation))
2256 return !Right.is(tok::l_paren);
2257 if (Right.is(TT_PointerOrReference))
2258 return Line.IsMultiVariableDeclStmt ||
2259 (Style.PointerAlignment == FormatStyle::PAS_Right &&
2260 (!Right.Next || Right.Next->isNot(TT_FunctionDeclarationName)));
2261 if (Right.isOneOf(TT_StartOfName, TT_FunctionDeclarationName) ||
2262 Right.is(tok::kw_operator))
2263 return true;
2264 if (Left.is(TT_PointerOrReference))
2265 return false;
2266 if (Right.isTrailingComment())
2267 // We rely on MustBreakBefore being set correctly here as we should not
2268 // change the "binding" behavior of a comment.
2269 // The first comment in a braced lists is always interpreted as belonging to
2270 // the first list element. Otherwise, it should be placed outside of the
2271 // list.
2272 return Left.BlockKind == BK_BracedInit;
2273 if (Left.is(tok::question) && Right.is(tok::colon))
2274 return false;
2275 if (Right.is(TT_ConditionalExpr) || Right.is(tok::question))
2276 return Style.BreakBeforeTernaryOperators;
2277 if (Left.is(TT_ConditionalExpr) || Left.is(tok::question))
2278 return !Style.BreakBeforeTernaryOperators;
2279 if (Right.is(TT_InheritanceColon))
2280 return true;
2281 if (Right.is(tok::colon) &&
2282 !Right.isOneOf(TT_CtorInitializerColon, TT_InlineASMColon))
2283 return false;
2284 if (Left.is(tok::colon) && (Left.isOneOf(TT_DictLiteral, TT_ObjCMethodExpr)))
2285 return true;
2286 if (Right.is(TT_SelectorName) || (Right.is(tok::identifier) && Right.Next &&
2287 Right.Next->is(TT_ObjCMethodExpr)))
2288 return Left.isNot(tok::period); // FIXME: Properly parse ObjC calls.
2289 if (Left.is(tok::r_paren) && Line.Type == LT_ObjCProperty)
2290 return true;
2291 if (Left.ClosesTemplateDeclaration || Left.is(TT_FunctionAnnotationRParen))
2292 return true;
2293 if (Right.isOneOf(TT_RangeBasedForLoopColon, TT_OverloadedOperatorLParen,
2294 TT_OverloadedOperator))
2295 return false;
2296 if (Left.is(TT_RangeBasedForLoopColon))
2297 return true;
2298 if (Right.is(TT_RangeBasedForLoopColon))
2299 return false;
2300 if (Left.isOneOf(TT_TemplateCloser, TT_UnaryOperator) ||
2301 Left.is(tok::kw_operator))
2302 return false;
2303 if (Left.is(tok::equal) && !Right.isOneOf(tok::kw_default, tok::kw_delete) &&
2304 Line.Type == LT_VirtualFunctionDecl && Left.NestingLevel == 0)
2305 return false;
2306 if (Left.is(tok::l_paren) && Left.is(TT_AttributeParen))
2307 return false;
2308 if (Left.is(tok::l_paren) && Left.Previous &&
2309 (Left.Previous->isOneOf(TT_BinaryOperator, TT_CastRParen)))
2310 return false;
2311 if (Right.is(TT_ImplicitStringLiteral))
2312 return false;
2313
2314 if (Right.is(tok::r_paren) || Right.is(TT_TemplateCloser))
2315 return false;
2316 if (Right.is(tok::r_square) && Right.MatchingParen &&
2317 Right.MatchingParen->is(TT_LambdaLSquare))
2318 return false;
2319
2320 // We only break before r_brace if there was a corresponding break before
2321 // the l_brace, which is tracked by BreakBeforeClosingBrace.
2322 if (Right.is(tok::r_brace))
2323 return Right.MatchingParen && Right.MatchingParen->BlockKind == BK_Block;
2324
2325 // Allow breaking after a trailing annotation, e.g. after a method
2326 // declaration.
2327 if (Left.is(TT_TrailingAnnotation))
2328 return !Right.isOneOf(tok::l_brace, tok::semi, tok::equal, tok::l_paren,
2329 tok::less, tok::coloncolon);
2330
2331 if (Right.is(tok::kw___attribute))
2332 return true;
2333
2334 if (Left.is(tok::identifier) && Right.is(tok::string_literal))
2335 return true;
2336
2337 if (Right.is(tok::identifier) && Right.Next && Right.Next->is(TT_DictLiteral))
2338 return true;
2339
2340 if (Left.is(TT_CtorInitializerComma) &&
2341 Style.BreakConstructorInitializersBeforeComma)
2342 return false;
2343 if (Right.is(TT_CtorInitializerComma) &&
2344 Style.BreakConstructorInitializersBeforeComma)
2345 return true;
2346 if ((Left.is(tok::greater) && Right.is(tok::greater)) ||
2347 (Left.is(tok::less) && Right.is(tok::less)))
2348 return false;
2349 if (Right.is(TT_BinaryOperator) &&
2350 Style.BreakBeforeBinaryOperators != FormatStyle::BOS_None &&
2351 (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_All ||
2352 Right.getPrecedence() != prec::Assignment))
2353 return true;
2354 if (Left.is(TT_ArrayInitializerLSquare))
2355 return true;
2356 if (Right.is(tok::kw_typename) && Left.isNot(tok::kw_const))
2357 return true;
2358 if ((Left.isBinaryOperator() || Left.is(TT_BinaryOperator)) &&
2359 !Left.isOneOf(tok::arrowstar, tok::lessless) &&
2360 Style.BreakBeforeBinaryOperators != FormatStyle::BOS_All &&
2361 (Style.BreakBeforeBinaryOperators == FormatStyle::BOS_None ||
2362 Left.getPrecedence() == prec::Assignment))
2363 return true;
2364 return Left.isOneOf(tok::comma, tok::coloncolon, tok::semi, tok::l_brace,
2365 tok::kw_class, tok::kw_struct) ||
2366 Right.isMemberAccess() ||
2367 Right.isOneOf(TT_TrailingReturnArrow, TT_LambdaArrow, tok::lessless,
2368 tok::colon, tok::l_square, tok::at) ||
2369 (Left.is(tok::r_paren) &&
2370 Right.isOneOf(tok::identifier, tok::kw_const)) ||
2371 (Left.is(tok::l_paren) && !Right.is(tok::r_paren));
2372 }
2373
printDebugInfo(const AnnotatedLine & Line)2374 void TokenAnnotator::printDebugInfo(const AnnotatedLine &Line) {
2375 llvm::errs() << "AnnotatedTokens:\n";
2376 const FormatToken *Tok = Line.First;
2377 while (Tok) {
2378 llvm::errs() << " M=" << Tok->MustBreakBefore
2379 << " C=" << Tok->CanBreakBefore
2380 << " T=" << getTokenTypeName(Tok->Type)
2381 << " S=" << Tok->SpacesRequiredBefore
2382 << " B=" << Tok->BlockParameterCount
2383 << " P=" << Tok->SplitPenalty << " Name=" << Tok->Tok.getName()
2384 << " L=" << Tok->TotalLength << " PPK=" << Tok->PackingKind
2385 << " FakeLParens=";
2386 for (unsigned i = 0, e = Tok->FakeLParens.size(); i != e; ++i)
2387 llvm::errs() << Tok->FakeLParens[i] << "/";
2388 llvm::errs() << " FakeRParens=" << Tok->FakeRParens << "\n";
2389 if (!Tok->Next)
2390 assert(Tok == Line.Last);
2391 Tok = Tok->Next;
2392 }
2393 llvm::errs() << "----\n";
2394 }
2395
2396 } // namespace format
2397 } // namespace clang
2398