xref: /llvm-project/clang/lib/AST/CommentSema.cpp (revision efe4bfa623d40f8221f449c3dd38392101a53599) 
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/Decl.h"
13 #include "clang/AST/DeclTemplate.h"
14 #include "clang/Basic/DiagnosticComment.h"
15 #include "clang/Basic/LLVM.h"
16 #include "clang/Basic/SourceManager.h"
17 #include "clang/Lex/Preprocessor.h"
18 #include "llvm/ADT/StringSwitch.h"
19 
20 namespace clang {
21 namespace comments {
22 
23 namespace {
24 #include "clang/AST/CommentHTMLTagsProperties.inc"
25 } // end anonymous namespace
26 
27 Sema::Sema(llvm::BumpPtrAllocator &Allocator, const SourceManager &SourceMgr,
28            DiagnosticsEngine &Diags, CommandTraits &Traits,
29            const Preprocessor *PP) :
30     Allocator(Allocator), SourceMgr(SourceMgr), Diags(Diags), Traits(Traits),
31     PP(PP), ThisDeclInfo(nullptr), BriefCommand(nullptr),
32     HeaderfileCommand(nullptr) {
33 }
34 
35 void Sema::setDecl(const Decl *D) {
36   if (!D)
37     return;
38 
39   ThisDeclInfo = new (Allocator) DeclInfo;
40   ThisDeclInfo->CommentDecl = D;
41   ThisDeclInfo->IsFilled = false;
42 }
43 
44 ParagraphComment *Sema::actOnParagraphComment(
45                               ArrayRef<InlineContentComment *> Content) {
46   return new (Allocator) ParagraphComment(Content);
47 }
48 
49 BlockCommandComment *Sema::actOnBlockCommandStart(
50                                       SourceLocation LocBegin,
51                                       SourceLocation LocEnd,
52                                       unsigned CommandID,
53                                       CommandMarkerKind CommandMarker) {
54   BlockCommandComment *BC = new (Allocator) BlockCommandComment(LocBegin, LocEnd,
55                                                                 CommandID,
56                                                                 CommandMarker);
57   checkContainerDecl(BC);
58   return BC;
59 }
60 
61 void Sema::actOnBlockCommandArgs(BlockCommandComment *Command,
62                                  ArrayRef<BlockCommandComment::Argument> Args) {
63   Command->setArgs(Args);
64 }
65 
66 void Sema::actOnBlockCommandFinish(BlockCommandComment *Command,
67                                    ParagraphComment *Paragraph) {
68   Command->setParagraph(Paragraph);
69   checkBlockCommandEmptyParagraph(Command);
70   checkBlockCommandDuplicate(Command);
71   if (ThisDeclInfo) {
72     // These checks only make sense if the comment is attached to a
73     // declaration.
74     checkReturnsCommand(Command);
75     checkDeprecatedCommand(Command);
76   }
77 }
78 
79 ParamCommandComment *Sema::actOnParamCommandStart(
80                                       SourceLocation LocBegin,
81                                       SourceLocation LocEnd,
82                                       unsigned CommandID,
83                                       CommandMarkerKind CommandMarker) {
84   ParamCommandComment *Command =
85       new (Allocator) ParamCommandComment(LocBegin, LocEnd, CommandID,
86                                           CommandMarker);
87 
88   if (!involvesFunctionType())
89     Diag(Command->getLocation(),
90          diag::warn_doc_param_not_attached_to_a_function_decl)
91       << CommandMarker
92       << Command->getCommandNameRange(Traits);
93 
94   return Command;
95 }
96 
97 void Sema::checkFunctionDeclVerbatimLine(const BlockCommandComment *Comment) {
98   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
99   if (!Info->IsFunctionDeclarationCommand)
100     return;
101 
102   unsigned DiagSelect;
103   switch (Comment->getCommandID()) {
104     case CommandTraits::KCI_function:
105       DiagSelect = (!isAnyFunctionDecl() && !isFunctionTemplateDecl())? 1 : 0;
106       break;
107     case CommandTraits::KCI_functiongroup:
108       DiagSelect = (!isAnyFunctionDecl() && !isFunctionTemplateDecl())? 2 : 0;
109       break;
110     case CommandTraits::KCI_method:
111       DiagSelect = !isObjCMethodDecl() ? 3 : 0;
112       break;
113     case CommandTraits::KCI_methodgroup:
114       DiagSelect = !isObjCMethodDecl() ? 4 : 0;
115       break;
116     case CommandTraits::KCI_callback:
117       DiagSelect = !isFunctionPointerVarDecl() ? 5 : 0;
118       break;
119     default:
120       DiagSelect = 0;
121       break;
122   }
123   if (DiagSelect)
124     Diag(Comment->getLocation(), diag::warn_doc_function_method_decl_mismatch)
125     << Comment->getCommandMarker()
126     << (DiagSelect-1) << (DiagSelect-1)
127     << Comment->getSourceRange();
128 }
129 
130 void Sema::checkContainerDeclVerbatimLine(const BlockCommandComment *Comment) {
131   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
132   if (!Info->IsRecordLikeDeclarationCommand)
133     return;
134   unsigned DiagSelect;
135   switch (Comment->getCommandID()) {
136     case CommandTraits::KCI_class:
137       DiagSelect =
138           (!isClassOrStructOrTagTypedefDecl() && !isClassTemplateDecl()) ? 1
139                                                                          : 0;
140       // Allow @class command on @interface declarations.
141       // FIXME. Currently, \class and @class are indistinguishable. So,
142       // \class is also allowed on an @interface declaration
143       if (DiagSelect && Comment->getCommandMarker() && isObjCInterfaceDecl())
144         DiagSelect = 0;
145       break;
146     case CommandTraits::KCI_interface:
147       DiagSelect = !isObjCInterfaceDecl() ? 2 : 0;
148       break;
149     case CommandTraits::KCI_protocol:
150       DiagSelect = !isObjCProtocolDecl() ? 3 : 0;
151       break;
152     case CommandTraits::KCI_struct:
153       DiagSelect = !isClassOrStructOrTagTypedefDecl() ? 4 : 0;
154       break;
155     case CommandTraits::KCI_union:
156       DiagSelect = !isUnionDecl() ? 5 : 0;
157       break;
158     default:
159       DiagSelect = 0;
160       break;
161   }
162   if (DiagSelect)
163     Diag(Comment->getLocation(), diag::warn_doc_api_container_decl_mismatch)
164     << Comment->getCommandMarker()
165     << (DiagSelect-1) << (DiagSelect-1)
166     << Comment->getSourceRange();
167 }
168 
169 void Sema::checkContainerDecl(const BlockCommandComment *Comment) {
170   const CommandInfo *Info = Traits.getCommandInfo(Comment->getCommandID());
171   if (!Info->IsRecordLikeDetailCommand || isRecordLikeDecl())
172     return;
173   unsigned DiagSelect;
174   switch (Comment->getCommandID()) {
175     case CommandTraits::KCI_classdesign:
176       DiagSelect = 1;
177       break;
178     case CommandTraits::KCI_coclass:
179       DiagSelect = 2;
180       break;
181     case CommandTraits::KCI_dependency:
182       DiagSelect = 3;
183       break;
184     case CommandTraits::KCI_helper:
185       DiagSelect = 4;
186       break;
187     case CommandTraits::KCI_helperclass:
188       DiagSelect = 5;
189       break;
190     case CommandTraits::KCI_helps:
191       DiagSelect = 6;
192       break;
193     case CommandTraits::KCI_instancesize:
194       DiagSelect = 7;
195       break;
196     case CommandTraits::KCI_ownership:
197       DiagSelect = 8;
198       break;
199     case CommandTraits::KCI_performance:
200       DiagSelect = 9;
201       break;
202     case CommandTraits::KCI_security:
203       DiagSelect = 10;
204       break;
205     case CommandTraits::KCI_superclass:
206       DiagSelect = 11;
207       break;
208     default:
209       DiagSelect = 0;
210       break;
211   }
212   if (DiagSelect)
213     Diag(Comment->getLocation(), diag::warn_doc_container_decl_mismatch)
214     << Comment->getCommandMarker()
215     << (DiagSelect-1)
216     << Comment->getSourceRange();
217 }
218 
219 /// Turn a string into the corresponding PassDirection or -1 if it's not
220 /// valid.
221 static ParamCommandPassDirection getParamPassDirection(StringRef Arg) {
222   return llvm::StringSwitch<ParamCommandPassDirection>(Arg)
223       .Case("[in]", ParamCommandPassDirection::In)
224       .Case("[out]", ParamCommandPassDirection::Out)
225       .Cases("[in,out]", "[out,in]", ParamCommandPassDirection::InOut)
226       .Default(static_cast<ParamCommandPassDirection>(-1));
227 }
228 
229 void Sema::actOnParamCommandDirectionArg(ParamCommandComment *Command,
230                                          SourceLocation ArgLocBegin,
231                                          SourceLocation ArgLocEnd,
232                                          StringRef Arg) {
233   std::string ArgLower = Arg.lower();
234   ParamCommandPassDirection Direction = getParamPassDirection(ArgLower);
235 
236   if (Direction == static_cast<ParamCommandPassDirection>(-1)) {
237     // Try again with whitespace removed.
238     llvm::erase_if(ArgLower, clang::isWhitespace);
239     Direction = getParamPassDirection(ArgLower);
240 
241     SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
242     if (Direction != static_cast<ParamCommandPassDirection>(-1)) {
243       const char *FixedName =
244           ParamCommandComment::getDirectionAsString(Direction);
245       Diag(ArgLocBegin, diag::warn_doc_param_spaces_in_direction)
246           << ArgRange << FixItHint::CreateReplacement(ArgRange, FixedName);
247     } else {
248       Diag(ArgLocBegin, diag::warn_doc_param_invalid_direction) << ArgRange;
249       Direction = ParamCommandPassDirection::In; // Sane fall back.
250     }
251   }
252   Command->setDirection(Direction,
253                         /*Explicit=*/true);
254 }
255 
256 void Sema::actOnParamCommandParamNameArg(ParamCommandComment *Command,
257                                          SourceLocation ArgLocBegin,
258                                          SourceLocation ArgLocEnd,
259                                          StringRef Arg) {
260   // Parser will not feed us more arguments than needed.
261   assert(Command->getNumArgs() == 0);
262 
263   if (!Command->isDirectionExplicit()) {
264     // User didn't provide a direction argument.
265     Command->setDirection(ParamCommandPassDirection::In,
266                           /* Explicit = */ false);
267   }
268   auto *A = new (Allocator)
269       Comment::Argument{SourceRange(ArgLocBegin, ArgLocEnd), Arg};
270   Command->setArgs(llvm::ArrayRef(A, 1));
271 }
272 
273 void Sema::actOnParamCommandFinish(ParamCommandComment *Command,
274                                    ParagraphComment *Paragraph) {
275   Command->setParagraph(Paragraph);
276   checkBlockCommandEmptyParagraph(Command);
277 }
278 
279 TParamCommandComment *Sema::actOnTParamCommandStart(
280                                       SourceLocation LocBegin,
281                                       SourceLocation LocEnd,
282                                       unsigned CommandID,
283                                       CommandMarkerKind CommandMarker) {
284   TParamCommandComment *Command =
285       new (Allocator) TParamCommandComment(LocBegin, LocEnd, CommandID,
286                                            CommandMarker);
287 
288   if (!isTemplateOrSpecialization())
289     Diag(Command->getLocation(),
290          diag::warn_doc_tparam_not_attached_to_a_template_decl)
291       << CommandMarker
292       << Command->getCommandNameRange(Traits);
293 
294   return Command;
295 }
296 
297 void Sema::actOnTParamCommandParamNameArg(TParamCommandComment *Command,
298                                           SourceLocation ArgLocBegin,
299                                           SourceLocation ArgLocEnd,
300                                           StringRef Arg) {
301   // Parser will not feed us more arguments than needed.
302   assert(Command->getNumArgs() == 0);
303 
304   auto *A = new (Allocator)
305       Comment::Argument{SourceRange(ArgLocBegin, ArgLocEnd), Arg};
306   Command->setArgs(llvm::ArrayRef(A, 1));
307 
308   if (!isTemplateOrSpecialization()) {
309     // We already warned that this \\tparam is not attached to a template decl.
310     return;
311   }
312 
313   const TemplateParameterList *TemplateParameters =
314       ThisDeclInfo->TemplateParameters;
315   SmallVector<unsigned, 2> Position;
316   if (resolveTParamReference(Arg, TemplateParameters, &Position)) {
317     Command->setPosition(copyArray(llvm::ArrayRef(Position)));
318     TParamCommandComment *&PrevCommand = TemplateParameterDocs[Arg];
319     if (PrevCommand) {
320       SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
321       Diag(ArgLocBegin, diag::warn_doc_tparam_duplicate)
322         << Arg << ArgRange;
323       Diag(PrevCommand->getLocation(), diag::note_doc_tparam_previous)
324         << PrevCommand->getParamNameRange();
325     }
326     PrevCommand = Command;
327     return;
328   }
329 
330   SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
331   Diag(ArgLocBegin, diag::warn_doc_tparam_not_found)
332     << Arg << ArgRange;
333 
334   if (!TemplateParameters || TemplateParameters->size() == 0)
335     return;
336 
337   StringRef CorrectedName;
338   if (TemplateParameters->size() == 1) {
339     const NamedDecl *Param = TemplateParameters->getParam(0);
340     const IdentifierInfo *II = Param->getIdentifier();
341     if (II)
342       CorrectedName = II->getName();
343   } else {
344     CorrectedName = correctTypoInTParamReference(Arg, TemplateParameters);
345   }
346 
347   if (!CorrectedName.empty()) {
348     Diag(ArgLocBegin, diag::note_doc_tparam_name_suggestion)
349       << CorrectedName
350       << FixItHint::CreateReplacement(ArgRange, CorrectedName);
351   }
352 }
353 
354 void Sema::actOnTParamCommandFinish(TParamCommandComment *Command,
355                                     ParagraphComment *Paragraph) {
356   Command->setParagraph(Paragraph);
357   checkBlockCommandEmptyParagraph(Command);
358 }
359 
360 InlineCommandComment *
361 Sema::actOnInlineCommand(SourceLocation CommandLocBegin,
362                          SourceLocation CommandLocEnd, unsigned CommandID,
363                          ArrayRef<Comment::Argument> Args) {
364   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
365 
366   return new (Allocator)
367       InlineCommandComment(CommandLocBegin, CommandLocEnd, CommandID,
368                            getInlineCommandRenderKind(CommandName), Args);
369 }
370 
371 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
372                                                 SourceLocation LocEnd,
373                                                 StringRef CommandName) {
374   unsigned CommandID = Traits.registerUnknownCommand(CommandName)->getID();
375   return actOnUnknownCommand(LocBegin, LocEnd, CommandID);
376 }
377 
378 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
379                                                 SourceLocation LocEnd,
380                                                 unsigned CommandID) {
381   ArrayRef<InlineCommandComment::Argument> Args;
382   return new (Allocator) InlineCommandComment(
383       LocBegin, LocEnd, CommandID, InlineCommandRenderKind::Normal, Args);
384 }
385 
386 TextComment *Sema::actOnText(SourceLocation LocBegin,
387                              SourceLocation LocEnd,
388                              StringRef Text) {
389   return new (Allocator) TextComment(LocBegin, LocEnd, Text);
390 }
391 
392 VerbatimBlockComment *Sema::actOnVerbatimBlockStart(SourceLocation Loc,
393                                                     unsigned CommandID) {
394   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
395   return new (Allocator) VerbatimBlockComment(
396                                   Loc,
397                                   Loc.getLocWithOffset(1 + CommandName.size()),
398                                   CommandID);
399 }
400 
401 VerbatimBlockLineComment *Sema::actOnVerbatimBlockLine(SourceLocation Loc,
402                                                        StringRef Text) {
403   return new (Allocator) VerbatimBlockLineComment(Loc, Text);
404 }
405 
406 void Sema::actOnVerbatimBlockFinish(
407                             VerbatimBlockComment *Block,
408                             SourceLocation CloseNameLocBegin,
409                             StringRef CloseName,
410                             ArrayRef<VerbatimBlockLineComment *> Lines) {
411   Block->setCloseName(CloseName, CloseNameLocBegin);
412   Block->setLines(Lines);
413 }
414 
415 VerbatimLineComment *Sema::actOnVerbatimLine(SourceLocation LocBegin,
416                                              unsigned CommandID,
417                                              SourceLocation TextBegin,
418                                              StringRef Text) {
419   VerbatimLineComment *VL = new (Allocator) VerbatimLineComment(
420                               LocBegin,
421                               TextBegin.getLocWithOffset(Text.size()),
422                               CommandID,
423                               TextBegin,
424                               Text);
425   checkFunctionDeclVerbatimLine(VL);
426   checkContainerDeclVerbatimLine(VL);
427   return VL;
428 }
429 
430 HTMLStartTagComment *Sema::actOnHTMLStartTagStart(SourceLocation LocBegin,
431                                                   StringRef TagName) {
432   return new (Allocator) HTMLStartTagComment(LocBegin, TagName);
433 }
434 
435 void Sema::actOnHTMLStartTagFinish(
436                               HTMLStartTagComment *Tag,
437                               ArrayRef<HTMLStartTagComment::Attribute> Attrs,
438                               SourceLocation GreaterLoc,
439                               bool IsSelfClosing) {
440   Tag->setAttrs(Attrs);
441   Tag->setGreaterLoc(GreaterLoc);
442   if (IsSelfClosing)
443     Tag->setSelfClosing();
444   else if (!isHTMLEndTagForbidden(Tag->getTagName()))
445     HTMLOpenTags.push_back(Tag);
446 }
447 
448 HTMLEndTagComment *Sema::actOnHTMLEndTag(SourceLocation LocBegin,
449                                          SourceLocation LocEnd,
450                                          StringRef TagName) {
451   HTMLEndTagComment *HET =
452       new (Allocator) HTMLEndTagComment(LocBegin, LocEnd, TagName);
453   if (isHTMLEndTagForbidden(TagName)) {
454     Diag(HET->getLocation(), diag::warn_doc_html_end_forbidden)
455       << TagName << HET->getSourceRange();
456     HET->setIsMalformed();
457     return HET;
458   }
459 
460   bool FoundOpen = false;
461   for (SmallVectorImpl<HTMLStartTagComment *>::const_reverse_iterator
462        I = HTMLOpenTags.rbegin(), E = HTMLOpenTags.rend();
463        I != E; ++I) {
464     if ((*I)->getTagName() == TagName) {
465       FoundOpen = true;
466       break;
467     }
468   }
469   if (!FoundOpen) {
470     Diag(HET->getLocation(), diag::warn_doc_html_end_unbalanced)
471       << HET->getSourceRange();
472     HET->setIsMalformed();
473     return HET;
474   }
475 
476   while (!HTMLOpenTags.empty()) {
477     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
478     StringRef LastNotClosedTagName = HST->getTagName();
479     if (LastNotClosedTagName == TagName) {
480       // If the start tag is malformed, end tag is malformed as well.
481       if (HST->isMalformed())
482         HET->setIsMalformed();
483       break;
484     }
485 
486     if (isHTMLEndTagOptional(LastNotClosedTagName))
487       continue;
488 
489     bool OpenLineInvalid;
490     const unsigned OpenLine = SourceMgr.getPresumedLineNumber(
491                                                 HST->getLocation(),
492                                                 &OpenLineInvalid);
493     bool CloseLineInvalid;
494     const unsigned CloseLine = SourceMgr.getPresumedLineNumber(
495                                                 HET->getLocation(),
496                                                 &CloseLineInvalid);
497 
498     if (OpenLineInvalid || CloseLineInvalid || OpenLine == CloseLine) {
499       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
500         << HST->getTagName() << HET->getTagName()
501         << HST->getSourceRange() << HET->getSourceRange();
502       HST->setIsMalformed();
503     } else {
504       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
505         << HST->getTagName() << HET->getTagName()
506         << HST->getSourceRange();
507       Diag(HET->getLocation(), diag::note_doc_html_end_tag)
508         << HET->getSourceRange();
509       HST->setIsMalformed();
510     }
511   }
512 
513   return HET;
514 }
515 
516 FullComment *Sema::actOnFullComment(
517                               ArrayRef<BlockContentComment *> Blocks) {
518   FullComment *FC = new (Allocator) FullComment(Blocks, ThisDeclInfo);
519   resolveParamCommandIndexes(FC);
520 
521   // Complain about HTML tags that are not closed.
522   while (!HTMLOpenTags.empty()) {
523     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
524     if (isHTMLEndTagOptional(HST->getTagName()))
525       continue;
526 
527     Diag(HST->getLocation(), diag::warn_doc_html_missing_end_tag)
528       << HST->getTagName() << HST->getSourceRange();
529     HST->setIsMalformed();
530   }
531 
532   return FC;
533 }
534 
535 void Sema::checkBlockCommandEmptyParagraph(BlockCommandComment *Command) {
536   if (Traits.getCommandInfo(Command->getCommandID())->IsEmptyParagraphAllowed)
537     return;
538 
539   ParagraphComment *Paragraph = Command->getParagraph();
540   if (Paragraph->isWhitespace()) {
541     SourceLocation DiagLoc;
542     if (Command->getNumArgs() > 0)
543       DiagLoc = Command->getArgRange(Command->getNumArgs() - 1).getEnd();
544     if (!DiagLoc.isValid())
545       DiagLoc = Command->getCommandNameRange(Traits).getEnd();
546     Diag(DiagLoc, diag::warn_doc_block_command_empty_paragraph)
547       << Command->getCommandMarker()
548       << Command->getCommandName(Traits)
549       << Command->getSourceRange();
550   }
551 }
552 
553 void Sema::checkReturnsCommand(const BlockCommandComment *Command) {
554   if (!Traits.getCommandInfo(Command->getCommandID())->IsReturnsCommand)
555     return;
556 
557   assert(ThisDeclInfo && "should not call this check on a bare comment");
558 
559   // We allow the return command for all @properties because it can be used
560   // to document the value that the property getter returns.
561   if (isObjCPropertyDecl())
562     return;
563   if (involvesFunctionType()) {
564     assert(!ThisDeclInfo->ReturnType.isNull() &&
565            "should have a valid return type");
566     if (ThisDeclInfo->ReturnType->isVoidType()) {
567       unsigned DiagKind;
568       switch (ThisDeclInfo->CommentDecl->getKind()) {
569       default:
570         if (ThisDeclInfo->IsObjCMethod)
571           DiagKind = 3;
572         else
573           DiagKind = 0;
574         break;
575       case Decl::CXXConstructor:
576         DiagKind = 1;
577         break;
578       case Decl::CXXDestructor:
579         DiagKind = 2;
580         break;
581       }
582       Diag(Command->getLocation(),
583            diag::warn_doc_returns_attached_to_a_void_function)
584         << Command->getCommandMarker()
585         << Command->getCommandName(Traits)
586         << DiagKind
587         << Command->getSourceRange();
588     }
589     return;
590   }
591 
592   Diag(Command->getLocation(),
593        diag::warn_doc_returns_not_attached_to_a_function_decl)
594     << Command->getCommandMarker()
595     << Command->getCommandName(Traits)
596     << Command->getSourceRange();
597 }
598 
599 void Sema::checkBlockCommandDuplicate(const BlockCommandComment *Command) {
600   const CommandInfo *Info = Traits.getCommandInfo(Command->getCommandID());
601   const BlockCommandComment *PrevCommand = nullptr;
602   if (Info->IsBriefCommand) {
603     if (!BriefCommand) {
604       BriefCommand = Command;
605       return;
606     }
607     PrevCommand = BriefCommand;
608   } else if (Info->IsHeaderfileCommand) {
609     if (!HeaderfileCommand) {
610       HeaderfileCommand = Command;
611       return;
612     }
613     PrevCommand = HeaderfileCommand;
614   } else {
615     // We don't want to check this command for duplicates.
616     return;
617   }
618   StringRef CommandName = Command->getCommandName(Traits);
619   StringRef PrevCommandName = PrevCommand->getCommandName(Traits);
620   Diag(Command->getLocation(), diag::warn_doc_block_command_duplicate)
621       << Command->getCommandMarker()
622       << CommandName
623       << Command->getSourceRange();
624   if (CommandName == PrevCommandName)
625     Diag(PrevCommand->getLocation(), diag::note_doc_block_command_previous)
626         << PrevCommand->getCommandMarker()
627         << PrevCommandName
628         << PrevCommand->getSourceRange();
629   else
630     Diag(PrevCommand->getLocation(),
631          diag::note_doc_block_command_previous_alias)
632         << PrevCommand->getCommandMarker()
633         << PrevCommandName
634         << CommandName;
635 }
636 
637 void Sema::checkDeprecatedCommand(const BlockCommandComment *Command) {
638   if (!Traits.getCommandInfo(Command->getCommandID())->IsDeprecatedCommand)
639     return;
640 
641   assert(ThisDeclInfo && "should not call this check on a bare comment");
642 
643   const Decl *D = ThisDeclInfo->CommentDecl;
644   if (!D)
645     return;
646 
647   if (D->hasAttr<DeprecatedAttr>() ||
648       D->hasAttr<AvailabilityAttr>() ||
649       D->hasAttr<UnavailableAttr>())
650     return;
651 
652   Diag(Command->getLocation(), diag::warn_doc_deprecated_not_sync)
653       << Command->getSourceRange() << Command->getCommandMarker();
654 
655   // Try to emit a fixit with a deprecation attribute.
656   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
657     // Don't emit a Fix-It for non-member function definitions.  GCC does not
658     // accept attributes on them.
659     const DeclContext *Ctx = FD->getDeclContext();
660     if ((!Ctx || !Ctx->isRecord()) &&
661         FD->doesThisDeclarationHaveABody())
662       return;
663 
664     const LangOptions &LO = FD->getLangOpts();
665     const bool DoubleSquareBracket = LO.CPlusPlus14 || LO.C23;
666     StringRef AttributeSpelling =
667         DoubleSquareBracket ? "[[deprecated]]" : "__attribute__((deprecated))";
668     if (PP) {
669       // Try to find a replacement macro:
670       // - In C23/C++14 we prefer [[deprecated]].
671       // - If not found or an older C/C++ look for __attribute__((deprecated)).
672       StringRef MacroName;
673       if (DoubleSquareBracket) {
674         TokenValue Tokens[] = {tok::l_square, tok::l_square,
675                                PP->getIdentifierInfo("deprecated"),
676                                tok::r_square, tok::r_square};
677         MacroName = PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
678         if (!MacroName.empty())
679           AttributeSpelling = MacroName;
680       }
681 
682       if (MacroName.empty()) {
683         TokenValue Tokens[] = {
684             tok::kw___attribute, tok::l_paren,
685             tok::l_paren,        PP->getIdentifierInfo("deprecated"),
686             tok::r_paren,        tok::r_paren};
687         StringRef MacroName =
688             PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
689         if (!MacroName.empty())
690           AttributeSpelling = MacroName;
691       }
692     }
693 
694     SmallString<64> TextToInsert = AttributeSpelling;
695     TextToInsert += " ";
696     SourceLocation Loc = FD->getSourceRange().getBegin();
697     Diag(Loc, diag::note_add_deprecation_attr)
698         << FixItHint::CreateInsertion(Loc, TextToInsert);
699   }
700 }
701 
702 void Sema::resolveParamCommandIndexes(const FullComment *FC) {
703   if (!involvesFunctionType()) {
704     // We already warned that \\param commands are not attached to a function
705     // decl.
706     return;
707   }
708 
709   SmallVector<ParamCommandComment *, 8> UnresolvedParamCommands;
710 
711   // Comment AST nodes that correspond to \c ParamVars for which we have
712   // found a \\param command or NULL if no documentation was found so far.
713   SmallVector<ParamCommandComment *, 8> ParamVarDocs;
714 
715   ArrayRef<const ParmVarDecl *> ParamVars = getParamVars();
716   ParamVarDocs.resize(ParamVars.size(), nullptr);
717 
718   // First pass over all \\param commands: resolve all parameter names.
719   for (Comment::child_iterator I = FC->child_begin(), E = FC->child_end();
720        I != E; ++I) {
721     ParamCommandComment *PCC = dyn_cast<ParamCommandComment>(*I);
722     if (!PCC || !PCC->hasParamName())
723       continue;
724     StringRef ParamName = PCC->getParamNameAsWritten();
725 
726     // Check that referenced parameter name is in the function decl.
727     const unsigned ResolvedParamIndex = resolveParmVarReference(ParamName,
728                                                                 ParamVars);
729     if (ResolvedParamIndex == ParamCommandComment::VarArgParamIndex) {
730       PCC->setIsVarArgParam();
731       continue;
732     }
733     if (ResolvedParamIndex == ParamCommandComment::InvalidParamIndex) {
734       UnresolvedParamCommands.push_back(PCC);
735       continue;
736     }
737     PCC->setParamIndex(ResolvedParamIndex);
738     if (ParamVarDocs[ResolvedParamIndex]) {
739       SourceRange ArgRange = PCC->getParamNameRange();
740       Diag(ArgRange.getBegin(), diag::warn_doc_param_duplicate)
741         << ParamName << ArgRange;
742       ParamCommandComment *PrevCommand = ParamVarDocs[ResolvedParamIndex];
743       Diag(PrevCommand->getLocation(), diag::note_doc_param_previous)
744         << PrevCommand->getParamNameRange();
745     }
746     ParamVarDocs[ResolvedParamIndex] = PCC;
747   }
748 
749   // Find parameter declarations that have no corresponding \\param.
750   SmallVector<const ParmVarDecl *, 8> OrphanedParamDecls;
751   for (unsigned i = 0, e = ParamVarDocs.size(); i != e; ++i) {
752     if (!ParamVarDocs[i])
753       OrphanedParamDecls.push_back(ParamVars[i]);
754   }
755 
756   // Second pass over unresolved \\param commands: do typo correction.
757   // Suggest corrections from a set of parameter declarations that have no
758   // corresponding \\param.
759   for (unsigned i = 0, e = UnresolvedParamCommands.size(); i != e; ++i) {
760     const ParamCommandComment *PCC = UnresolvedParamCommands[i];
761 
762     SourceRange ArgRange = PCC->getParamNameRange();
763     StringRef ParamName = PCC->getParamNameAsWritten();
764     Diag(ArgRange.getBegin(), diag::warn_doc_param_not_found)
765       << ParamName << ArgRange;
766 
767     // All parameters documented -- can't suggest a correction.
768     if (OrphanedParamDecls.size() == 0)
769       continue;
770 
771     unsigned CorrectedParamIndex = ParamCommandComment::InvalidParamIndex;
772     if (OrphanedParamDecls.size() == 1) {
773       // If one parameter is not documented then that parameter is the only
774       // possible suggestion.
775       CorrectedParamIndex = 0;
776     } else {
777       // Do typo correction.
778       CorrectedParamIndex = correctTypoInParmVarReference(ParamName,
779                                                           OrphanedParamDecls);
780     }
781     if (CorrectedParamIndex != ParamCommandComment::InvalidParamIndex) {
782       const ParmVarDecl *CorrectedPVD = OrphanedParamDecls[CorrectedParamIndex];
783       if (const IdentifierInfo *CorrectedII = CorrectedPVD->getIdentifier())
784         Diag(ArgRange.getBegin(), diag::note_doc_param_name_suggestion)
785           << CorrectedII->getName()
786           << FixItHint::CreateReplacement(ArgRange, CorrectedII->getName());
787     }
788   }
789 }
790 
791 bool Sema::involvesFunctionType() {
792   if (!ThisDeclInfo)
793     return false;
794   if (!ThisDeclInfo->IsFilled)
795     inspectThisDecl();
796   return ThisDeclInfo->involvesFunctionType();
797 }
798 
799 bool Sema::isFunctionDecl() {
800   if (!ThisDeclInfo)
801     return false;
802   if (!ThisDeclInfo->IsFilled)
803     inspectThisDecl();
804   return ThisDeclInfo->getKind() == DeclInfo::FunctionKind;
805 }
806 
807 bool Sema::isAnyFunctionDecl() {
808   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
809          isa<FunctionDecl>(ThisDeclInfo->CurrentDecl);
810 }
811 
812 bool Sema::isFunctionOrMethodVariadic() {
813   if (!ThisDeclInfo)
814     return false;
815   if (!ThisDeclInfo->IsFilled)
816     inspectThisDecl();
817   return ThisDeclInfo->IsVariadic;
818 }
819 
820 bool Sema::isObjCMethodDecl() {
821   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
822          isa<ObjCMethodDecl>(ThisDeclInfo->CurrentDecl);
823 }
824 
825 bool Sema::isFunctionPointerVarDecl() {
826   if (!ThisDeclInfo)
827     return false;
828   if (!ThisDeclInfo->IsFilled)
829     inspectThisDecl();
830   if (ThisDeclInfo->getKind() == DeclInfo::VariableKind) {
831     if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDeclInfo->CurrentDecl)) {
832       QualType QT = VD->getType();
833       return QT->isFunctionPointerType();
834     }
835   }
836   return false;
837 }
838 
839 bool Sema::isObjCPropertyDecl() {
840   if (!ThisDeclInfo)
841     return false;
842   if (!ThisDeclInfo->IsFilled)
843     inspectThisDecl();
844   return ThisDeclInfo->CurrentDecl->getKind() == Decl::ObjCProperty;
845 }
846 
847 bool Sema::isTemplateOrSpecialization() {
848   if (!ThisDeclInfo)
849     return false;
850   if (!ThisDeclInfo->IsFilled)
851     inspectThisDecl();
852   return ThisDeclInfo->getTemplateKind() != DeclInfo::NotTemplate;
853 }
854 
855 bool Sema::isRecordLikeDecl() {
856   if (!ThisDeclInfo)
857     return false;
858   if (!ThisDeclInfo->IsFilled)
859     inspectThisDecl();
860   return isUnionDecl() || isClassOrStructDecl() || isObjCInterfaceDecl() ||
861          isObjCProtocolDecl();
862 }
863 
864 bool Sema::isUnionDecl() {
865   if (!ThisDeclInfo)
866     return false;
867   if (!ThisDeclInfo->IsFilled)
868     inspectThisDecl();
869   if (const RecordDecl *RD =
870         dyn_cast_or_null<RecordDecl>(ThisDeclInfo->CurrentDecl))
871     return RD->isUnion();
872   return false;
873 }
874 static bool isClassOrStructDeclImpl(const Decl *D) {
875   if (auto *record = dyn_cast_or_null<RecordDecl>(D))
876     return !record->isUnion();
877 
878   return false;
879 }
880 
881 bool Sema::isClassOrStructDecl() {
882   if (!ThisDeclInfo)
883     return false;
884   if (!ThisDeclInfo->IsFilled)
885     inspectThisDecl();
886 
887   if (!ThisDeclInfo->CurrentDecl)
888     return false;
889 
890   return isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl);
891 }
892 
893 bool Sema::isClassOrStructOrTagTypedefDecl() {
894   if (!ThisDeclInfo)
895     return false;
896   if (!ThisDeclInfo->IsFilled)
897     inspectThisDecl();
898 
899   if (!ThisDeclInfo->CurrentDecl)
900     return false;
901 
902   if (isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl))
903     return true;
904 
905   if (auto *ThisTypedefDecl = dyn_cast<TypedefDecl>(ThisDeclInfo->CurrentDecl)) {
906     auto UnderlyingType = ThisTypedefDecl->getUnderlyingType();
907     if (auto ThisElaboratedType = dyn_cast<ElaboratedType>(UnderlyingType)) {
908       auto DesugaredType = ThisElaboratedType->desugar();
909       if (auto *DesugaredTypePtr = DesugaredType.getTypePtrOrNull()) {
910         if (auto *ThisRecordType = dyn_cast<RecordType>(DesugaredTypePtr)) {
911           return isClassOrStructDeclImpl(ThisRecordType->getAsRecordDecl());
912         }
913       }
914     }
915   }
916 
917   return false;
918 }
919 
920 bool Sema::isClassTemplateDecl() {
921   if (!ThisDeclInfo)
922     return false;
923   if (!ThisDeclInfo->IsFilled)
924     inspectThisDecl();
925   return ThisDeclInfo->CurrentDecl &&
926           (isa<ClassTemplateDecl>(ThisDeclInfo->CurrentDecl));
927 }
928 
929 bool Sema::isFunctionTemplateDecl() {
930   if (!ThisDeclInfo)
931     return false;
932   if (!ThisDeclInfo->IsFilled)
933     inspectThisDecl();
934   return ThisDeclInfo->CurrentDecl &&
935          (isa<FunctionTemplateDecl>(ThisDeclInfo->CurrentDecl));
936 }
937 
938 bool Sema::isObjCInterfaceDecl() {
939   if (!ThisDeclInfo)
940     return false;
941   if (!ThisDeclInfo->IsFilled)
942     inspectThisDecl();
943   return ThisDeclInfo->CurrentDecl &&
944          isa<ObjCInterfaceDecl>(ThisDeclInfo->CurrentDecl);
945 }
946 
947 bool Sema::isObjCProtocolDecl() {
948   if (!ThisDeclInfo)
949     return false;
950   if (!ThisDeclInfo->IsFilled)
951     inspectThisDecl();
952   return ThisDeclInfo->CurrentDecl &&
953          isa<ObjCProtocolDecl>(ThisDeclInfo->CurrentDecl);
954 }
955 
956 ArrayRef<const ParmVarDecl *> Sema::getParamVars() {
957   if (!ThisDeclInfo->IsFilled)
958     inspectThisDecl();
959   return ThisDeclInfo->ParamVars;
960 }
961 
962 void Sema::inspectThisDecl() {
963   ThisDeclInfo->fill();
964 }
965 
966 unsigned Sema::resolveParmVarReference(StringRef Name,
967                                        ArrayRef<const ParmVarDecl *> ParamVars) {
968   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i) {
969     const IdentifierInfo *II = ParamVars[i]->getIdentifier();
970     if (II && II->getName() == Name)
971       return i;
972   }
973   if (Name == "..." && isFunctionOrMethodVariadic())
974     return ParamCommandComment::VarArgParamIndex;
975   return ParamCommandComment::InvalidParamIndex;
976 }
977 
978 namespace {
979 class SimpleTypoCorrector {
980   const NamedDecl *BestDecl;
981 
982   StringRef Typo;
983   const unsigned MaxEditDistance;
984 
985   unsigned BestEditDistance;
986   unsigned BestIndex;
987   unsigned NextIndex;
988 
989 public:
990   explicit SimpleTypoCorrector(StringRef Typo)
991       : BestDecl(nullptr), Typo(Typo), MaxEditDistance((Typo.size() + 2) / 3),
992         BestEditDistance(MaxEditDistance + 1), BestIndex(0), NextIndex(0) {}
993 
994   void addDecl(const NamedDecl *ND);
995 
996   const NamedDecl *getBestDecl() const {
997     if (BestEditDistance > MaxEditDistance)
998       return nullptr;
999 
1000     return BestDecl;
1001   }
1002 
1003   unsigned getBestDeclIndex() const {
1004     assert(getBestDecl());
1005     return BestIndex;
1006   }
1007 };
1008 
1009 void SimpleTypoCorrector::addDecl(const NamedDecl *ND) {
1010   unsigned CurrIndex = NextIndex++;
1011 
1012   const IdentifierInfo *II = ND->getIdentifier();
1013   if (!II)
1014     return;
1015 
1016   StringRef Name = II->getName();
1017   unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size());
1018   if (MinPossibleEditDistance > 0 &&
1019       Typo.size() / MinPossibleEditDistance < 3)
1020     return;
1021 
1022   unsigned EditDistance = Typo.edit_distance(Name, true, MaxEditDistance);
1023   if (EditDistance < BestEditDistance) {
1024     BestEditDistance = EditDistance;
1025     BestDecl = ND;
1026     BestIndex = CurrIndex;
1027   }
1028 }
1029 } // end anonymous namespace
1030 
1031 unsigned Sema::correctTypoInParmVarReference(
1032                                     StringRef Typo,
1033                                     ArrayRef<const ParmVarDecl *> ParamVars) {
1034   SimpleTypoCorrector Corrector(Typo);
1035   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i)
1036     Corrector.addDecl(ParamVars[i]);
1037   if (Corrector.getBestDecl())
1038     return Corrector.getBestDeclIndex();
1039   else
1040     return ParamCommandComment::InvalidParamIndex;
1041 }
1042 
1043 namespace {
1044 bool ResolveTParamReferenceHelper(
1045                             StringRef Name,
1046                             const TemplateParameterList *TemplateParameters,
1047                             SmallVectorImpl<unsigned> *Position) {
1048   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1049     const NamedDecl *Param = TemplateParameters->getParam(i);
1050     const IdentifierInfo *II = Param->getIdentifier();
1051     if (II && II->getName() == Name) {
1052       Position->push_back(i);
1053       return true;
1054     }
1055 
1056     if (const TemplateTemplateParmDecl *TTP =
1057             dyn_cast<TemplateTemplateParmDecl>(Param)) {
1058       Position->push_back(i);
1059       if (ResolveTParamReferenceHelper(Name, TTP->getTemplateParameters(),
1060                                        Position))
1061         return true;
1062       Position->pop_back();
1063     }
1064   }
1065   return false;
1066 }
1067 } // end anonymous namespace
1068 
1069 bool Sema::resolveTParamReference(
1070                             StringRef Name,
1071                             const TemplateParameterList *TemplateParameters,
1072                             SmallVectorImpl<unsigned> *Position) {
1073   Position->clear();
1074   if (!TemplateParameters)
1075     return false;
1076 
1077   return ResolveTParamReferenceHelper(Name, TemplateParameters, Position);
1078 }
1079 
1080 namespace {
1081 void CorrectTypoInTParamReferenceHelper(
1082                             const TemplateParameterList *TemplateParameters,
1083                             SimpleTypoCorrector &Corrector) {
1084   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1085     const NamedDecl *Param = TemplateParameters->getParam(i);
1086     Corrector.addDecl(Param);
1087 
1088     if (const TemplateTemplateParmDecl *TTP =
1089             dyn_cast<TemplateTemplateParmDecl>(Param))
1090       CorrectTypoInTParamReferenceHelper(TTP->getTemplateParameters(),
1091                                          Corrector);
1092   }
1093 }
1094 } // end anonymous namespace
1095 
1096 StringRef Sema::correctTypoInTParamReference(
1097                             StringRef Typo,
1098                             const TemplateParameterList *TemplateParameters) {
1099   SimpleTypoCorrector Corrector(Typo);
1100   CorrectTypoInTParamReferenceHelper(TemplateParameters, Corrector);
1101   if (const NamedDecl *ND = Corrector.getBestDecl()) {
1102     const IdentifierInfo *II = ND->getIdentifier();
1103     assert(II && "SimpleTypoCorrector should not return this decl");
1104     return II->getName();
1105   }
1106   return StringRef();
1107 }
1108 
1109 InlineCommandRenderKind Sema::getInlineCommandRenderKind(StringRef Name) const {
1110   assert(Traits.getCommandInfo(Name)->IsInlineCommand);
1111 
1112   return llvm::StringSwitch<InlineCommandRenderKind>(Name)
1113       .Case("b", InlineCommandRenderKind::Bold)
1114       .Cases("c", "p", InlineCommandRenderKind::Monospaced)
1115       .Cases("a", "e", "em", InlineCommandRenderKind::Emphasized)
1116       .Case("anchor", InlineCommandRenderKind::Anchor)
1117       .Default(InlineCommandRenderKind::Normal);
1118 }
1119 
1120 } // end namespace comments
1121 } // end namespace clang
1122