xref: /freebsd/contrib/llvm-project/clang/lib/AST/CommentSema.cpp (revision 994297b01b98816bea1abf45ae4bac1bc69ee7a0) 
1 //===--- CommentSema.cpp - Doxygen comment semantic analysis --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "clang/AST/CommentSema.h"
10 #include "clang/AST/Attr.h"
11 #include "clang/AST/CommentCommandTraits.h"
12 #include "clang/AST/CommentDiagnostic.h"
13 #include "clang/AST/Decl.h"
14 #include "clang/AST/DeclTemplate.h"
15 #include "clang/Basic/LLVM.h"
16 #include "clang/Basic/SourceManager.h"
17 #include "clang/Lex/Preprocessor.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/StringSwitch.h"
20 
21 namespace clang {
22 namespace comments {
23 
24 namespace {
25 #include "clang/AST/CommentHTMLTagsProperties.inc"
26 } // end anonymous namespace
27 
28 Sema::Sema(llvm::BumpPtrAllocator &Allocator, const SourceManager &SourceMgr,
29            DiagnosticsEngine &Diags, CommandTraits &Traits,
30            const Preprocessor *PP) :
31     Allocator(Allocator), SourceMgr(SourceMgr), Diags(Diags), Traits(Traits),
32     PP(PP), ThisDeclInfo(nullptr), BriefCommand(nullptr),
33     HeaderfileCommand(nullptr) {
34 }
35 
36 void Sema::setDecl(const Decl *D) {
37   if (!D)
38     return;
39 
40   ThisDeclInfo = new (Allocator) DeclInfo;
41   ThisDeclInfo->CommentDecl = D;
42   ThisDeclInfo->IsFilled = false;
43 }
44 
45 ParagraphComment *Sema::actOnParagraphComment(
46                               ArrayRef<InlineContentComment *> Content) {
47   return new (Allocator) ParagraphComment(Content);
48 }
49 
50 BlockCommandComment *Sema::actOnBlockCommandStart(
51                                       SourceLocation LocBegin,
52                                       SourceLocation LocEnd,
53                                       unsigned CommandID,
54                                       CommandMarkerKind CommandMarker) {
55   BlockCommandComment *BC = new (Allocator) BlockCommandComment(LocBegin, LocEnd,
56                                                                 CommandID,
57                                                                 CommandMarker);
58   checkContainerDecl(BC);
59   return BC;
60 }
61 
62 void Sema::actOnBlockCommandArgs(BlockCommandComment *Command,
63                                  ArrayRef<BlockCommandComment::Argument> Args) {
64   Command->setArgs(Args);
65 }
66 
67 void Sema::actOnBlockCommandFinish(BlockCommandComment *Command,
68                                    ParagraphComment *Paragraph) {
69   Command->setParagraph(Paragraph);
70   checkBlockCommandEmptyParagraph(Command);
71   checkBlockCommandDuplicate(Command);
72   if (ThisDeclInfo) {
73     // These checks only make sense if the comment is attached to a
74     // declaration.
75     checkReturnsCommand(Command);
76     checkDeprecatedCommand(Command);
77   }
78 }
79 
80 ParamCommandComment *Sema::actOnParamCommandStart(
81                                       SourceLocation LocBegin,
82                                       SourceLocation LocEnd,
83                                       unsigned CommandID,
84                                       CommandMarkerKind CommandMarker) {
85   ParamCommandComment *Command =
86       new (Allocator) ParamCommandComment(LocBegin, LocEnd, CommandID,
87                                           CommandMarker);
88 
89   if (!isFunctionDecl() && !isFunctionOrBlockPointerVarLikeDecl())
90     Diag(Command->getLocation(),
91          diag::warn_doc_param_not_attached_to_a_function_decl)
92       << CommandMarker
93       << Command->getCommandNameRange(Traits);
94 
95   return Command;
96 }
97 
98 void Sema::checkFunctionDeclVerbatimLine(const BlockCommandComment *Comment) {
99   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
100   if (!Info->IsFunctionDeclarationCommand)
101     return;
102 
103   unsigned DiagSelect;
104   switch (Comment->getCommandID()) {
105     case CommandTraits::KCI_function:
106       DiagSelect = (!isAnyFunctionDecl() && !isFunctionTemplateDecl())? 1 : 0;
107       break;
108     case CommandTraits::KCI_functiongroup:
109       DiagSelect = (!isAnyFunctionDecl() && !isFunctionTemplateDecl())? 2 : 0;
110       break;
111     case CommandTraits::KCI_method:
112       DiagSelect = !isObjCMethodDecl() ? 3 : 0;
113       break;
114     case CommandTraits::KCI_methodgroup:
115       DiagSelect = !isObjCMethodDecl() ? 4 : 0;
116       break;
117     case CommandTraits::KCI_callback:
118       DiagSelect = !isFunctionPointerVarDecl() ? 5 : 0;
119       break;
120     default:
121       DiagSelect = 0;
122       break;
123   }
124   if (DiagSelect)
125     Diag(Comment->getLocation(), diag::warn_doc_function_method_decl_mismatch)
126     << Comment->getCommandMarker()
127     << (DiagSelect-1) << (DiagSelect-1)
128     << Comment->getSourceRange();
129 }
130 
131 void Sema::checkContainerDeclVerbatimLine(const BlockCommandComment *Comment) {
132   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
133   if (!Info->IsRecordLikeDeclarationCommand)
134     return;
135   unsigned DiagSelect;
136   switch (Comment->getCommandID()) {
137     case CommandTraits::KCI_class:
138       DiagSelect =
139           (!isClassOrStructOrTagTypedefDecl() && !isClassTemplateDecl()) ? 1
140                                                                          : 0;
141       // Allow @class command on @interface declarations.
142       // FIXME. Currently, \class and @class are indistinguishable. So,
143       // \class is also allowed on an @interface declaration
144       if (DiagSelect && Comment->getCommandMarker() && isObjCInterfaceDecl())
145         DiagSelect = 0;
146       break;
147     case CommandTraits::KCI_interface:
148       DiagSelect = !isObjCInterfaceDecl() ? 2 : 0;
149       break;
150     case CommandTraits::KCI_protocol:
151       DiagSelect = !isObjCProtocolDecl() ? 3 : 0;
152       break;
153     case CommandTraits::KCI_struct:
154       DiagSelect = !isClassOrStructOrTagTypedefDecl() ? 4 : 0;
155       break;
156     case CommandTraits::KCI_union:
157       DiagSelect = !isUnionDecl() ? 5 : 0;
158       break;
159     default:
160       DiagSelect = 0;
161       break;
162   }
163   if (DiagSelect)
164     Diag(Comment->getLocation(), diag::warn_doc_api_container_decl_mismatch)
165     << Comment->getCommandMarker()
166     << (DiagSelect-1) << (DiagSelect-1)
167     << Comment->getSourceRange();
168 }
169 
170 void Sema::checkContainerDecl(const BlockCommandComment *Comment) {
171   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
172   if (!Info->IsRecordLikeDetailCommand || isRecordLikeDecl())
173     return;
174   unsigned DiagSelect;
175   switch (Comment->getCommandID()) {
176     case CommandTraits::KCI_classdesign:
177       DiagSelect = 1;
178       break;
179     case CommandTraits::KCI_coclass:
180       DiagSelect = 2;
181       break;
182     case CommandTraits::KCI_dependency:
183       DiagSelect = 3;
184       break;
185     case CommandTraits::KCI_helper:
186       DiagSelect = 4;
187       break;
188     case CommandTraits::KCI_helperclass:
189       DiagSelect = 5;
190       break;
191     case CommandTraits::KCI_helps:
192       DiagSelect = 6;
193       break;
194     case CommandTraits::KCI_instancesize:
195       DiagSelect = 7;
196       break;
197     case CommandTraits::KCI_ownership:
198       DiagSelect = 8;
199       break;
200     case CommandTraits::KCI_performance:
201       DiagSelect = 9;
202       break;
203     case CommandTraits::KCI_security:
204       DiagSelect = 10;
205       break;
206     case CommandTraits::KCI_superclass:
207       DiagSelect = 11;
208       break;
209     default:
210       DiagSelect = 0;
211       break;
212   }
213   if (DiagSelect)
214     Diag(Comment->getLocation(), diag::warn_doc_container_decl_mismatch)
215     << Comment->getCommandMarker()
216     << (DiagSelect-1)
217     << Comment->getSourceRange();
218 }
219 
220 /// Turn a string into the corresponding PassDirection or -1 if it's not
221 /// valid.
222 static int getParamPassDirection(StringRef Arg) {
223   return llvm::StringSwitch<int>(Arg)
224       .Case("[in]", ParamCommandComment::In)
225       .Case("[out]", ParamCommandComment::Out)
226       .Cases("[in,out]", "[out,in]", ParamCommandComment::InOut)
227       .Default(-1);
228 }
229 
230 void Sema::actOnParamCommandDirectionArg(ParamCommandComment *Command,
231                                          SourceLocation ArgLocBegin,
232                                          SourceLocation ArgLocEnd,
233                                          StringRef Arg) {
234   std::string ArgLower = Arg.lower();
235   int Direction = getParamPassDirection(ArgLower);
236 
237   if (Direction == -1) {
238     // Try again with whitespace removed.
239     ArgLower.erase(
240         std::remove_if(ArgLower.begin(), ArgLower.end(), clang::isWhitespace),
241         ArgLower.end());
242     Direction = getParamPassDirection(ArgLower);
243 
244     SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
245     if (Direction != -1) {
246       const char *FixedName = ParamCommandComment::getDirectionAsString(
247           (ParamCommandComment::PassDirection)Direction);
248       Diag(ArgLocBegin, diag::warn_doc_param_spaces_in_direction)
249           << ArgRange << FixItHint::CreateReplacement(ArgRange, FixedName);
250     } else {
251       Diag(ArgLocBegin, diag::warn_doc_param_invalid_direction) << ArgRange;
252       Direction = ParamCommandComment::In; // Sane fall back.
253     }
254   }
255   Command->setDirection((ParamCommandComment::PassDirection)Direction,
256                         /*Explicit=*/true);
257 }
258 
259 void Sema::actOnParamCommandParamNameArg(ParamCommandComment *Command,
260                                          SourceLocation ArgLocBegin,
261                                          SourceLocation ArgLocEnd,
262                                          StringRef Arg) {
263   // Parser will not feed us more arguments than needed.
264   assert(Command->getNumArgs() == 0);
265 
266   if (!Command->isDirectionExplicit()) {
267     // User didn't provide a direction argument.
268     Command->setDirection(ParamCommandComment::In, /* Explicit = */ false);
269   }
270   typedef BlockCommandComment::Argument Argument;
271   Argument *A = new (Allocator) Argument(SourceRange(ArgLocBegin,
272                                                      ArgLocEnd),
273                                          Arg);
274   Command->setArgs(llvm::makeArrayRef(A, 1));
275 }
276 
277 void Sema::actOnParamCommandFinish(ParamCommandComment *Command,
278                                    ParagraphComment *Paragraph) {
279   Command->setParagraph(Paragraph);
280   checkBlockCommandEmptyParagraph(Command);
281 }
282 
283 TParamCommandComment *Sema::actOnTParamCommandStart(
284                                       SourceLocation LocBegin,
285                                       SourceLocation LocEnd,
286                                       unsigned CommandID,
287                                       CommandMarkerKind CommandMarker) {
288   TParamCommandComment *Command =
289       new (Allocator) TParamCommandComment(LocBegin, LocEnd, CommandID,
290                                            CommandMarker);
291 
292   if (!isTemplateOrSpecialization())
293     Diag(Command->getLocation(),
294          diag::warn_doc_tparam_not_attached_to_a_template_decl)
295       << CommandMarker
296       << Command->getCommandNameRange(Traits);
297 
298   return Command;
299 }
300 
301 void Sema::actOnTParamCommandParamNameArg(TParamCommandComment *Command,
302                                           SourceLocation ArgLocBegin,
303                                           SourceLocation ArgLocEnd,
304                                           StringRef Arg) {
305   // Parser will not feed us more arguments than needed.
306   assert(Command->getNumArgs() == 0);
307 
308   typedef BlockCommandComment::Argument Argument;
309   Argument *A = new (Allocator) Argument(SourceRange(ArgLocBegin,
310                                                      ArgLocEnd),
311                                          Arg);
312   Command->setArgs(llvm::makeArrayRef(A, 1));
313 
314   if (!isTemplateOrSpecialization()) {
315     // We already warned that this \\tparam is not attached to a template decl.
316     return;
317   }
318 
319   const TemplateParameterList *TemplateParameters =
320       ThisDeclInfo->TemplateParameters;
321   SmallVector<unsigned, 2> Position;
322   if (resolveTParamReference(Arg, TemplateParameters, &Position)) {
323     Command->setPosition(copyArray(llvm::makeArrayRef(Position)));
324     TParamCommandComment *&PrevCommand = TemplateParameterDocs[Arg];
325     if (PrevCommand) {
326       SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
327       Diag(ArgLocBegin, diag::warn_doc_tparam_duplicate)
328         << Arg << ArgRange;
329       Diag(PrevCommand->getLocation(), diag::note_doc_tparam_previous)
330         << PrevCommand->getParamNameRange();
331     }
332     PrevCommand = Command;
333     return;
334   }
335 
336   SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
337   Diag(ArgLocBegin, diag::warn_doc_tparam_not_found)
338     << Arg << ArgRange;
339 
340   if (!TemplateParameters || TemplateParameters->size() == 0)
341     return;
342 
343   StringRef CorrectedName;
344   if (TemplateParameters->size() == 1) {
345     const NamedDecl *Param = TemplateParameters->getParam(0);
346     const IdentifierInfo *II = Param->getIdentifier();
347     if (II)
348       CorrectedName = II->getName();
349   } else {
350     CorrectedName = correctTypoInTParamReference(Arg, TemplateParameters);
351   }
352 
353   if (!CorrectedName.empty()) {
354     Diag(ArgLocBegin, diag::note_doc_tparam_name_suggestion)
355       << CorrectedName
356       << FixItHint::CreateReplacement(ArgRange, CorrectedName);
357   }
358 }
359 
360 void Sema::actOnTParamCommandFinish(TParamCommandComment *Command,
361                                     ParagraphComment *Paragraph) {
362   Command->setParagraph(Paragraph);
363   checkBlockCommandEmptyParagraph(Command);
364 }
365 
366 InlineCommandComment *Sema::actOnInlineCommand(SourceLocation CommandLocBegin,
367                                                SourceLocation CommandLocEnd,
368                                                unsigned CommandID) {
369   ArrayRef<InlineCommandComment::Argument> Args;
370   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
371   return new (Allocator) InlineCommandComment(
372                                   CommandLocBegin,
373                                   CommandLocEnd,
374                                   CommandID,
375                                   getInlineCommandRenderKind(CommandName),
376                                   Args);
377 }
378 
379 InlineCommandComment *Sema::actOnInlineCommand(SourceLocation CommandLocBegin,
380                                                SourceLocation CommandLocEnd,
381                                                unsigned CommandID,
382                                                SourceLocation ArgLocBegin,
383                                                SourceLocation ArgLocEnd,
384                                                StringRef Arg) {
385   typedef InlineCommandComment::Argument Argument;
386   Argument *A = new (Allocator) Argument(SourceRange(ArgLocBegin,
387                                                      ArgLocEnd),
388                                          Arg);
389   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
390 
391   return new (Allocator) InlineCommandComment(
392                                   CommandLocBegin,
393                                   CommandLocEnd,
394                                   CommandID,
395                                   getInlineCommandRenderKind(CommandName),
396                                   llvm::makeArrayRef(A, 1));
397 }
398 
399 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
400                                                 SourceLocation LocEnd,
401                                                 StringRef CommandName) {
402   unsigned CommandID = Traits.registerUnknownCommand(CommandName)->getID();
403   return actOnUnknownCommand(LocBegin, LocEnd, CommandID);
404 }
405 
406 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
407                                                 SourceLocation LocEnd,
408                                                 unsigned CommandID) {
409   ArrayRef<InlineCommandComment::Argument> Args;
410   return new (Allocator) InlineCommandComment(
411                                   LocBegin, LocEnd, CommandID,
412                                   InlineCommandComment::RenderNormal,
413                                   Args);
414 }
415 
416 TextComment *Sema::actOnText(SourceLocation LocBegin,
417                              SourceLocation LocEnd,
418                              StringRef Text) {
419   return new (Allocator) TextComment(LocBegin, LocEnd, Text);
420 }
421 
422 VerbatimBlockComment *Sema::actOnVerbatimBlockStart(SourceLocation Loc,
423                                                     unsigned CommandID) {
424   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
425   return new (Allocator) VerbatimBlockComment(
426                                   Loc,
427                                   Loc.getLocWithOffset(1 + CommandName.size()),
428                                   CommandID);
429 }
430 
431 VerbatimBlockLineComment *Sema::actOnVerbatimBlockLine(SourceLocation Loc,
432                                                        StringRef Text) {
433   return new (Allocator) VerbatimBlockLineComment(Loc, Text);
434 }
435 
436 void Sema::actOnVerbatimBlockFinish(
437                             VerbatimBlockComment *Block,
438                             SourceLocation CloseNameLocBegin,
439                             StringRef CloseName,
440                             ArrayRef<VerbatimBlockLineComment *> Lines) {
441   Block->setCloseName(CloseName, CloseNameLocBegin);
442   Block->setLines(Lines);
443 }
444 
445 VerbatimLineComment *Sema::actOnVerbatimLine(SourceLocation LocBegin,
446                                              unsigned CommandID,
447                                              SourceLocation TextBegin,
448                                              StringRef Text) {
449   VerbatimLineComment *VL = new (Allocator) VerbatimLineComment(
450                               LocBegin,
451                               TextBegin.getLocWithOffset(Text.size()),
452                               CommandID,
453                               TextBegin,
454                               Text);
455   checkFunctionDeclVerbatimLine(VL);
456   checkContainerDeclVerbatimLine(VL);
457   return VL;
458 }
459 
460 HTMLStartTagComment *Sema::actOnHTMLStartTagStart(SourceLocation LocBegin,
461                                                   StringRef TagName) {
462   return new (Allocator) HTMLStartTagComment(LocBegin, TagName);
463 }
464 
465 void Sema::actOnHTMLStartTagFinish(
466                               HTMLStartTagComment *Tag,
467                               ArrayRef<HTMLStartTagComment::Attribute> Attrs,
468                               SourceLocation GreaterLoc,
469                               bool IsSelfClosing) {
470   Tag->setAttrs(Attrs);
471   Tag->setGreaterLoc(GreaterLoc);
472   if (IsSelfClosing)
473     Tag->setSelfClosing();
474   else if (!isHTMLEndTagForbidden(Tag->getTagName()))
475     HTMLOpenTags.push_back(Tag);
476 }
477 
478 HTMLEndTagComment *Sema::actOnHTMLEndTag(SourceLocation LocBegin,
479                                          SourceLocation LocEnd,
480                                          StringRef TagName) {
481   HTMLEndTagComment *HET =
482       new (Allocator) HTMLEndTagComment(LocBegin, LocEnd, TagName);
483   if (isHTMLEndTagForbidden(TagName)) {
484     Diag(HET->getLocation(), diag::warn_doc_html_end_forbidden)
485       << TagName << HET->getSourceRange();
486     HET->setIsMalformed();
487     return HET;
488   }
489 
490   bool FoundOpen = false;
491   for (SmallVectorImpl<HTMLStartTagComment *>::const_reverse_iterator
492        I = HTMLOpenTags.rbegin(), E = HTMLOpenTags.rend();
493        I != E; ++I) {
494     if ((*I)->getTagName() == TagName) {
495       FoundOpen = true;
496       break;
497     }
498   }
499   if (!FoundOpen) {
500     Diag(HET->getLocation(), diag::warn_doc_html_end_unbalanced)
501       << HET->getSourceRange();
502     HET->setIsMalformed();
503     return HET;
504   }
505 
506   while (!HTMLOpenTags.empty()) {
507     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
508     StringRef LastNotClosedTagName = HST->getTagName();
509     if (LastNotClosedTagName == TagName) {
510       // If the start tag is malformed, end tag is malformed as well.
511       if (HST->isMalformed())
512         HET->setIsMalformed();
513       break;
514     }
515 
516     if (isHTMLEndTagOptional(LastNotClosedTagName))
517       continue;
518 
519     bool OpenLineInvalid;
520     const unsigned OpenLine = SourceMgr.getPresumedLineNumber(
521                                                 HST->getLocation(),
522                                                 &OpenLineInvalid);
523     bool CloseLineInvalid;
524     const unsigned CloseLine = SourceMgr.getPresumedLineNumber(
525                                                 HET->getLocation(),
526                                                 &CloseLineInvalid);
527 
528     if (OpenLineInvalid || CloseLineInvalid || OpenLine == CloseLine) {
529       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
530         << HST->getTagName() << HET->getTagName()
531         << HST->getSourceRange() << HET->getSourceRange();
532       HST->setIsMalformed();
533     } else {
534       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
535         << HST->getTagName() << HET->getTagName()
536         << HST->getSourceRange();
537       Diag(HET->getLocation(), diag::note_doc_html_end_tag)
538         << HET->getSourceRange();
539       HST->setIsMalformed();
540     }
541   }
542 
543   return HET;
544 }
545 
546 FullComment *Sema::actOnFullComment(
547                               ArrayRef<BlockContentComment *> Blocks) {
548   FullComment *FC = new (Allocator) FullComment(Blocks, ThisDeclInfo);
549   resolveParamCommandIndexes(FC);
550 
551   // Complain about HTML tags that are not closed.
552   while (!HTMLOpenTags.empty()) {
553     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
554     if (isHTMLEndTagOptional(HST->getTagName()))
555       continue;
556 
557     Diag(HST->getLocation(), diag::warn_doc_html_missing_end_tag)
558       << HST->getTagName() << HST->getSourceRange();
559     HST->setIsMalformed();
560   }
561 
562   return FC;
563 }
564 
565 void Sema::checkBlockCommandEmptyParagraph(BlockCommandComment *Command) {
566   if (Traits.getCommandInfo(Command->getCommandID())->IsEmptyParagraphAllowed)
567     return;
568 
569   ParagraphComment *Paragraph = Command->getParagraph();
570   if (Paragraph->isWhitespace()) {
571     SourceLocation DiagLoc;
572     if (Command->getNumArgs() > 0)
573       DiagLoc = Command->getArgRange(Command->getNumArgs() - 1).getEnd();
574     if (!DiagLoc.isValid())
575       DiagLoc = Command->getCommandNameRange(Traits).getEnd();
576     Diag(DiagLoc, diag::warn_doc_block_command_empty_paragraph)
577       << Command->getCommandMarker()
578       << Command->getCommandName(Traits)
579       << Command->getSourceRange();
580   }
581 }
582 
583 void Sema::checkReturnsCommand(const BlockCommandComment *Command) {
584   if (!Traits.getCommandInfo(Command->getCommandID())->IsReturnsCommand)
585     return;
586 
587   assert(ThisDeclInfo && "should not call this check on a bare comment");
588 
589   // We allow the return command for all @properties because it can be used
590   // to document the value that the property getter returns.
591   if (isObjCPropertyDecl())
592     return;
593   if (isFunctionDecl() || isFunctionOrBlockPointerVarLikeDecl()) {
594     assert(!ThisDeclInfo->ReturnType.isNull() &&
595            "should have a valid return type");
596     if (ThisDeclInfo->ReturnType->isVoidType()) {
597       unsigned DiagKind;
598       switch (ThisDeclInfo->CommentDecl->getKind()) {
599       default:
600         if (ThisDeclInfo->IsObjCMethod)
601           DiagKind = 3;
602         else
603           DiagKind = 0;
604         break;
605       case Decl::CXXConstructor:
606         DiagKind = 1;
607         break;
608       case Decl::CXXDestructor:
609         DiagKind = 2;
610         break;
611       }
612       Diag(Command->getLocation(),
613            diag::warn_doc_returns_attached_to_a_void_function)
614         << Command->getCommandMarker()
615         << Command->getCommandName(Traits)
616         << DiagKind
617         << Command->getSourceRange();
618     }
619     return;
620   }
621 
622   Diag(Command->getLocation(),
623        diag::warn_doc_returns_not_attached_to_a_function_decl)
624     << Command->getCommandMarker()
625     << Command->getCommandName(Traits)
626     << Command->getSourceRange();
627 }
628 
629 void Sema::checkBlockCommandDuplicate(const BlockCommandComment *Command) {
630   const CommandInfo *Info = Traits.getCommandInfo(Command->getCommandID());
631   const BlockCommandComment *PrevCommand = nullptr;
632   if (Info->IsBriefCommand) {
633     if (!BriefCommand) {
634       BriefCommand = Command;
635       return;
636     }
637     PrevCommand = BriefCommand;
638   } else if (Info->IsHeaderfileCommand) {
639     if (!HeaderfileCommand) {
640       HeaderfileCommand = Command;
641       return;
642     }
643     PrevCommand = HeaderfileCommand;
644   } else {
645     // We don't want to check this command for duplicates.
646     return;
647   }
648   StringRef CommandName = Command->getCommandName(Traits);
649   StringRef PrevCommandName = PrevCommand->getCommandName(Traits);
650   Diag(Command->getLocation(), diag::warn_doc_block_command_duplicate)
651       << Command->getCommandMarker()
652       << CommandName
653       << Command->getSourceRange();
654   if (CommandName == PrevCommandName)
655     Diag(PrevCommand->getLocation(), diag::note_doc_block_command_previous)
656         << PrevCommand->getCommandMarker()
657         << PrevCommandName
658         << PrevCommand->getSourceRange();
659   else
660     Diag(PrevCommand->getLocation(),
661          diag::note_doc_block_command_previous_alias)
662         << PrevCommand->getCommandMarker()
663         << PrevCommandName
664         << CommandName;
665 }
666 
667 void Sema::checkDeprecatedCommand(const BlockCommandComment *Command) {
668   if (!Traits.getCommandInfo(Command->getCommandID())->IsDeprecatedCommand)
669     return;
670 
671   assert(ThisDeclInfo && "should not call this check on a bare comment");
672 
673   const Decl *D = ThisDeclInfo->CommentDecl;
674   if (!D)
675     return;
676 
677   if (D->hasAttr<DeprecatedAttr>() ||
678       D->hasAttr<AvailabilityAttr>() ||
679       D->hasAttr<UnavailableAttr>())
680     return;
681 
682   Diag(Command->getLocation(), diag::warn_doc_deprecated_not_sync)
683       << Command->getSourceRange() << Command->getCommandMarker();
684 
685   // Try to emit a fixit with a deprecation attribute.
686   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
687     // Don't emit a Fix-It for non-member function definitions.  GCC does not
688     // accept attributes on them.
689     const DeclContext *Ctx = FD->getDeclContext();
690     if ((!Ctx || !Ctx->isRecord()) &&
691         FD->doesThisDeclarationHaveABody())
692       return;
693 
694     const LangOptions &LO = FD->getLangOpts();
695     const bool DoubleSquareBracket = LO.CPlusPlus14 || LO.C2x;
696     StringRef AttributeSpelling =
697         DoubleSquareBracket ? "[[deprecated]]" : "__attribute__((deprecated))";
698     if (PP) {
699       // Try to find a replacement macro:
700       // - In C2x/C++14 we prefer [[deprecated]].
701       // - If not found or an older C/C++ look for __attribute__((deprecated)).
702       StringRef MacroName;
703       if (DoubleSquareBracket) {
704         TokenValue Tokens[] = {tok::l_square, tok::l_square,
705                                PP->getIdentifierInfo("deprecated"),
706                                tok::r_square, tok::r_square};
707         MacroName = PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
708         if (!MacroName.empty())
709           AttributeSpelling = MacroName;
710       }
711 
712       if (MacroName.empty()) {
713         TokenValue Tokens[] = {
714             tok::kw___attribute, tok::l_paren,
715             tok::l_paren,        PP->getIdentifierInfo("deprecated"),
716             tok::r_paren,        tok::r_paren};
717         StringRef MacroName =
718             PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
719         if (!MacroName.empty())
720           AttributeSpelling = MacroName;
721       }
722     }
723 
724     SmallString<64> TextToInsert = AttributeSpelling;
725     TextToInsert += " ";
726     SourceLocation Loc = FD->getSourceRange().getBegin();
727     Diag(Loc, diag::note_add_deprecation_attr)
728         << FixItHint::CreateInsertion(Loc, TextToInsert);
729   }
730 }
731 
732 void Sema::resolveParamCommandIndexes(const FullComment *FC) {
733   if (!isFunctionDecl()) {
734     // We already warned that \\param commands are not attached to a function
735     // decl.
736     return;
737   }
738 
739   SmallVector<ParamCommandComment *, 8> UnresolvedParamCommands;
740 
741   // Comment AST nodes that correspond to \c ParamVars for which we have
742   // found a \\param command or NULL if no documentation was found so far.
743   SmallVector<ParamCommandComment *, 8> ParamVarDocs;
744 
745   ArrayRef<const ParmVarDecl *> ParamVars = getParamVars();
746   ParamVarDocs.resize(ParamVars.size(), nullptr);
747 
748   // First pass over all \\param commands: resolve all parameter names.
749   for (Comment::child_iterator I = FC->child_begin(), E = FC->child_end();
750        I != E; ++I) {
751     ParamCommandComment *PCC = dyn_cast<ParamCommandComment>(*I);
752     if (!PCC || !PCC->hasParamName())
753       continue;
754     StringRef ParamName = PCC->getParamNameAsWritten();
755 
756     // Check that referenced parameter name is in the function decl.
757     const unsigned ResolvedParamIndex = resolveParmVarReference(ParamName,
758                                                                 ParamVars);
759     if (ResolvedParamIndex == ParamCommandComment::VarArgParamIndex) {
760       PCC->setIsVarArgParam();
761       continue;
762     }
763     if (ResolvedParamIndex == ParamCommandComment::InvalidParamIndex) {
764       UnresolvedParamCommands.push_back(PCC);
765       continue;
766     }
767     PCC->setParamIndex(ResolvedParamIndex);
768     if (ParamVarDocs[ResolvedParamIndex]) {
769       SourceRange ArgRange = PCC->getParamNameRange();
770       Diag(ArgRange.getBegin(), diag::warn_doc_param_duplicate)
771         << ParamName << ArgRange;
772       ParamCommandComment *PrevCommand = ParamVarDocs[ResolvedParamIndex];
773       Diag(PrevCommand->getLocation(), diag::note_doc_param_previous)
774         << PrevCommand->getParamNameRange();
775     }
776     ParamVarDocs[ResolvedParamIndex] = PCC;
777   }
778 
779   // Find parameter declarations that have no corresponding \\param.
780   SmallVector<const ParmVarDecl *, 8> OrphanedParamDecls;
781   for (unsigned i = 0, e = ParamVarDocs.size(); i != e; ++i) {
782     if (!ParamVarDocs[i])
783       OrphanedParamDecls.push_back(ParamVars[i]);
784   }
785 
786   // Second pass over unresolved \\param commands: do typo correction.
787   // Suggest corrections from a set of parameter declarations that have no
788   // corresponding \\param.
789   for (unsigned i = 0, e = UnresolvedParamCommands.size(); i != e; ++i) {
790     const ParamCommandComment *PCC = UnresolvedParamCommands[i];
791 
792     SourceRange ArgRange = PCC->getParamNameRange();
793     StringRef ParamName = PCC->getParamNameAsWritten();
794     Diag(ArgRange.getBegin(), diag::warn_doc_param_not_found)
795       << ParamName << ArgRange;
796 
797     // All parameters documented -- can't suggest a correction.
798     if (OrphanedParamDecls.size() == 0)
799       continue;
800 
801     unsigned CorrectedParamIndex = ParamCommandComment::InvalidParamIndex;
802     if (OrphanedParamDecls.size() == 1) {
803       // If one parameter is not documented then that parameter is the only
804       // possible suggestion.
805       CorrectedParamIndex = 0;
806     } else {
807       // Do typo correction.
808       CorrectedParamIndex = correctTypoInParmVarReference(ParamName,
809                                                           OrphanedParamDecls);
810     }
811     if (CorrectedParamIndex != ParamCommandComment::InvalidParamIndex) {
812       const ParmVarDecl *CorrectedPVD = OrphanedParamDecls[CorrectedParamIndex];
813       if (const IdentifierInfo *CorrectedII = CorrectedPVD->getIdentifier())
814         Diag(ArgRange.getBegin(), diag::note_doc_param_name_suggestion)
815           << CorrectedII->getName()
816           << FixItHint::CreateReplacement(ArgRange, CorrectedII->getName());
817     }
818   }
819 }
820 
821 bool Sema::isFunctionDecl() {
822   if (!ThisDeclInfo)
823     return false;
824   if (!ThisDeclInfo->IsFilled)
825     inspectThisDecl();
826   return ThisDeclInfo->getKind() == DeclInfo::FunctionKind;
827 }
828 
829 bool Sema::isAnyFunctionDecl() {
830   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
831          isa<FunctionDecl>(ThisDeclInfo->CurrentDecl);
832 }
833 
834 bool Sema::isFunctionOrMethodVariadic() {
835   if (!isFunctionDecl() || !ThisDeclInfo->CurrentDecl)
836     return false;
837   if (const FunctionDecl *FD =
838         dyn_cast<FunctionDecl>(ThisDeclInfo->CurrentDecl))
839     return FD->isVariadic();
840   if (const FunctionTemplateDecl *FTD =
841         dyn_cast<FunctionTemplateDecl>(ThisDeclInfo->CurrentDecl))
842     return FTD->getTemplatedDecl()->isVariadic();
843   if (const ObjCMethodDecl *MD =
844         dyn_cast<ObjCMethodDecl>(ThisDeclInfo->CurrentDecl))
845     return MD->isVariadic();
846   if (const TypedefNameDecl *TD =
847           dyn_cast<TypedefNameDecl>(ThisDeclInfo->CurrentDecl)) {
848     QualType Type = TD->getUnderlyingType();
849     if (Type->isFunctionPointerType() || Type->isBlockPointerType())
850       Type = Type->getPointeeType();
851     if (const auto *FT = Type->getAs<FunctionProtoType>())
852       return FT->isVariadic();
853   }
854   return false;
855 }
856 
857 bool Sema::isObjCMethodDecl() {
858   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
859          isa<ObjCMethodDecl>(ThisDeclInfo->CurrentDecl);
860 }
861 
862 bool Sema::isFunctionPointerVarDecl() {
863   if (!ThisDeclInfo)
864     return false;
865   if (!ThisDeclInfo->IsFilled)
866     inspectThisDecl();
867   if (ThisDeclInfo->getKind() == DeclInfo::VariableKind) {
868     if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDeclInfo->CurrentDecl)) {
869       QualType QT = VD->getType();
870       return QT->isFunctionPointerType();
871     }
872   }
873   return false;
874 }
875 
876 bool Sema::isFunctionOrBlockPointerVarLikeDecl() {
877   if (!ThisDeclInfo)
878     return false;
879   if (!ThisDeclInfo->IsFilled)
880     inspectThisDecl();
881   if (ThisDeclInfo->getKind() != DeclInfo::VariableKind ||
882       !ThisDeclInfo->CurrentDecl)
883     return false;
884   QualType QT;
885   if (const auto *VD = dyn_cast<DeclaratorDecl>(ThisDeclInfo->CurrentDecl))
886     QT = VD->getType();
887   else if (const auto *PD =
888                dyn_cast<ObjCPropertyDecl>(ThisDeclInfo->CurrentDecl))
889     QT = PD->getType();
890   else
891     return false;
892   // We would like to warn about the 'returns'/'param' commands for
893   // variables that don't directly specify the function type, so type aliases
894   // can be ignored.
895   if (QT->getAs<TypedefType>())
896     return false;
897   if (const auto *P = QT->getAs<PointerType>())
898     if (P->getPointeeType()->getAs<TypedefType>())
899       return false;
900   if (const auto *P = QT->getAs<BlockPointerType>())
901     if (P->getPointeeType()->getAs<TypedefType>())
902       return false;
903   return QT->isFunctionPointerType() || QT->isBlockPointerType();
904 }
905 
906 bool Sema::isObjCPropertyDecl() {
907   if (!ThisDeclInfo)
908     return false;
909   if (!ThisDeclInfo->IsFilled)
910     inspectThisDecl();
911   return ThisDeclInfo->CurrentDecl->getKind() == Decl::ObjCProperty;
912 }
913 
914 bool Sema::isTemplateOrSpecialization() {
915   if (!ThisDeclInfo)
916     return false;
917   if (!ThisDeclInfo->IsFilled)
918     inspectThisDecl();
919   return ThisDeclInfo->getTemplateKind() != DeclInfo::NotTemplate;
920 }
921 
922 bool Sema::isRecordLikeDecl() {
923   if (!ThisDeclInfo)
924     return false;
925   if (!ThisDeclInfo->IsFilled)
926     inspectThisDecl();
927   return isUnionDecl() || isClassOrStructDecl() || isObjCInterfaceDecl() ||
928          isObjCProtocolDecl();
929 }
930 
931 bool Sema::isUnionDecl() {
932   if (!ThisDeclInfo)
933     return false;
934   if (!ThisDeclInfo->IsFilled)
935     inspectThisDecl();
936   if (const RecordDecl *RD =
937         dyn_cast_or_null<RecordDecl>(ThisDeclInfo->CurrentDecl))
938     return RD->isUnion();
939   return false;
940 }
941 static bool isClassOrStructDeclImpl(const Decl *D) {
942   if (auto *record = dyn_cast_or_null<RecordDecl>(D))
943     return !record->isUnion();
944 
945   return false;
946 }
947 
948 bool Sema::isClassOrStructDecl() {
949   if (!ThisDeclInfo)
950     return false;
951   if (!ThisDeclInfo->IsFilled)
952     inspectThisDecl();
953 
954   if (!ThisDeclInfo->CurrentDecl)
955     return false;
956 
957   return isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl);
958 }
959 
960 bool Sema::isClassOrStructOrTagTypedefDecl() {
961   if (!ThisDeclInfo)
962     return false;
963   if (!ThisDeclInfo->IsFilled)
964     inspectThisDecl();
965 
966   if (!ThisDeclInfo->CurrentDecl)
967     return false;
968 
969   if (isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl))
970     return true;
971 
972   if (auto *ThisTypedefDecl = dyn_cast<TypedefDecl>(ThisDeclInfo->CurrentDecl)) {
973     auto UnderlyingType = ThisTypedefDecl->getUnderlyingType();
974     if (auto ThisElaboratedType = dyn_cast<ElaboratedType>(UnderlyingType)) {
975       auto DesugaredType = ThisElaboratedType->desugar();
976       if (auto *DesugaredTypePtr = DesugaredType.getTypePtrOrNull()) {
977         if (auto *ThisRecordType = dyn_cast<RecordType>(DesugaredTypePtr)) {
978           return isClassOrStructDeclImpl(ThisRecordType->getAsRecordDecl());
979         }
980       }
981     }
982   }
983 
984   return false;
985 }
986 
987 bool Sema::isClassTemplateDecl() {
988   if (!ThisDeclInfo)
989     return false;
990   if (!ThisDeclInfo->IsFilled)
991     inspectThisDecl();
992   return ThisDeclInfo->CurrentDecl &&
993           (isa<ClassTemplateDecl>(ThisDeclInfo->CurrentDecl));
994 }
995 
996 bool Sema::isFunctionTemplateDecl() {
997   if (!ThisDeclInfo)
998     return false;
999   if (!ThisDeclInfo->IsFilled)
1000     inspectThisDecl();
1001   return ThisDeclInfo->CurrentDecl &&
1002          (isa<FunctionTemplateDecl>(ThisDeclInfo->CurrentDecl));
1003 }
1004 
1005 bool Sema::isObjCInterfaceDecl() {
1006   if (!ThisDeclInfo)
1007     return false;
1008   if (!ThisDeclInfo->IsFilled)
1009     inspectThisDecl();
1010   return ThisDeclInfo->CurrentDecl &&
1011          isa<ObjCInterfaceDecl>(ThisDeclInfo->CurrentDecl);
1012 }
1013 
1014 bool Sema::isObjCProtocolDecl() {
1015   if (!ThisDeclInfo)
1016     return false;
1017   if (!ThisDeclInfo->IsFilled)
1018     inspectThisDecl();
1019   return ThisDeclInfo->CurrentDecl &&
1020          isa<ObjCProtocolDecl>(ThisDeclInfo->CurrentDecl);
1021 }
1022 
1023 ArrayRef<const ParmVarDecl *> Sema::getParamVars() {
1024   if (!ThisDeclInfo->IsFilled)
1025     inspectThisDecl();
1026   return ThisDeclInfo->ParamVars;
1027 }
1028 
1029 void Sema::inspectThisDecl() {
1030   ThisDeclInfo->fill();
1031 }
1032 
1033 unsigned Sema::resolveParmVarReference(StringRef Name,
1034                                        ArrayRef<const ParmVarDecl *> ParamVars) {
1035   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i) {
1036     const IdentifierInfo *II = ParamVars[i]->getIdentifier();
1037     if (II && II->getName() == Name)
1038       return i;
1039   }
1040   if (Name == "..." && isFunctionOrMethodVariadic())
1041     return ParamCommandComment::VarArgParamIndex;
1042   return ParamCommandComment::InvalidParamIndex;
1043 }
1044 
1045 namespace {
1046 class SimpleTypoCorrector {
1047   const NamedDecl *BestDecl;
1048 
1049   StringRef Typo;
1050   const unsigned MaxEditDistance;
1051 
1052   unsigned BestEditDistance;
1053   unsigned BestIndex;
1054   unsigned NextIndex;
1055 
1056 public:
1057   explicit SimpleTypoCorrector(StringRef Typo)
1058       : BestDecl(nullptr), Typo(Typo), MaxEditDistance((Typo.size() + 2) / 3),
1059         BestEditDistance(MaxEditDistance + 1), BestIndex(0), NextIndex(0) {}
1060 
1061   void addDecl(const NamedDecl *ND);
1062 
1063   const NamedDecl *getBestDecl() const {
1064     if (BestEditDistance > MaxEditDistance)
1065       return nullptr;
1066 
1067     return BestDecl;
1068   }
1069 
1070   unsigned getBestDeclIndex() const {
1071     assert(getBestDecl());
1072     return BestIndex;
1073   }
1074 };
1075 
1076 void SimpleTypoCorrector::addDecl(const NamedDecl *ND) {
1077   unsigned CurrIndex = NextIndex++;
1078 
1079   const IdentifierInfo *II = ND->getIdentifier();
1080   if (!II)
1081     return;
1082 
1083   StringRef Name = II->getName();
1084   unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size());
1085   if (MinPossibleEditDistance > 0 &&
1086       Typo.size() / MinPossibleEditDistance < 3)
1087     return;
1088 
1089   unsigned EditDistance = Typo.edit_distance(Name, true, MaxEditDistance);
1090   if (EditDistance < BestEditDistance) {
1091     BestEditDistance = EditDistance;
1092     BestDecl = ND;
1093     BestIndex = CurrIndex;
1094   }
1095 }
1096 } // end anonymous namespace
1097 
1098 unsigned Sema::correctTypoInParmVarReference(
1099                                     StringRef Typo,
1100                                     ArrayRef<const ParmVarDecl *> ParamVars) {
1101   SimpleTypoCorrector Corrector(Typo);
1102   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i)
1103     Corrector.addDecl(ParamVars[i]);
1104   if (Corrector.getBestDecl())
1105     return Corrector.getBestDeclIndex();
1106   else
1107     return ParamCommandComment::InvalidParamIndex;
1108 }
1109 
1110 namespace {
1111 bool ResolveTParamReferenceHelper(
1112                             StringRef Name,
1113                             const TemplateParameterList *TemplateParameters,
1114                             SmallVectorImpl<unsigned> *Position) {
1115   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1116     const NamedDecl *Param = TemplateParameters->getParam(i);
1117     const IdentifierInfo *II = Param->getIdentifier();
1118     if (II && II->getName() == Name) {
1119       Position->push_back(i);
1120       return true;
1121     }
1122 
1123     if (const TemplateTemplateParmDecl *TTP =
1124             dyn_cast<TemplateTemplateParmDecl>(Param)) {
1125       Position->push_back(i);
1126       if (ResolveTParamReferenceHelper(Name, TTP->getTemplateParameters(),
1127                                        Position))
1128         return true;
1129       Position->pop_back();
1130     }
1131   }
1132   return false;
1133 }
1134 } // end anonymous namespace
1135 
1136 bool Sema::resolveTParamReference(
1137                             StringRef Name,
1138                             const TemplateParameterList *TemplateParameters,
1139                             SmallVectorImpl<unsigned> *Position) {
1140   Position->clear();
1141   if (!TemplateParameters)
1142     return false;
1143 
1144   return ResolveTParamReferenceHelper(Name, TemplateParameters, Position);
1145 }
1146 
1147 namespace {
1148 void CorrectTypoInTParamReferenceHelper(
1149                             const TemplateParameterList *TemplateParameters,
1150                             SimpleTypoCorrector &Corrector) {
1151   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1152     const NamedDecl *Param = TemplateParameters->getParam(i);
1153     Corrector.addDecl(Param);
1154 
1155     if (const TemplateTemplateParmDecl *TTP =
1156             dyn_cast<TemplateTemplateParmDecl>(Param))
1157       CorrectTypoInTParamReferenceHelper(TTP->getTemplateParameters(),
1158                                          Corrector);
1159   }
1160 }
1161 } // end anonymous namespace
1162 
1163 StringRef Sema::correctTypoInTParamReference(
1164                             StringRef Typo,
1165                             const TemplateParameterList *TemplateParameters) {
1166   SimpleTypoCorrector Corrector(Typo);
1167   CorrectTypoInTParamReferenceHelper(TemplateParameters, Corrector);
1168   if (const NamedDecl *ND = Corrector.getBestDecl()) {
1169     const IdentifierInfo *II = ND->getIdentifier();
1170     assert(II && "SimpleTypoCorrector should not return this decl");
1171     return II->getName();
1172   }
1173   return StringRef();
1174 }
1175 
1176 InlineCommandComment::RenderKind
1177 Sema::getInlineCommandRenderKind(StringRef Name) const {
1178   assert(Traits.getCommandInfo(Name)->IsInlineCommand);
1179 
1180   return llvm::StringSwitch<InlineCommandComment::RenderKind>(Name)
1181       .Case("b", InlineCommandComment::RenderBold)
1182       .Cases("c", "p", InlineCommandComment::RenderMonospaced)
1183       .Cases("a", "e", "em", InlineCommandComment::RenderEmphasized)
1184       .Case("anchor", InlineCommandComment::RenderAnchor)
1185       .Default(InlineCommandComment::RenderNormal);
1186 }
1187 
1188 } // end namespace comments
1189 } // end namespace clang
1190