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 (!involvesFunctionType())
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 ParamCommandPassDirection getParamPassDirection(StringRef Arg) {
223   return llvm::StringSwitch<ParamCommandPassDirection>(Arg)
224       .Case("[in]", ParamCommandPassDirection::In)
225       .Case("[out]", ParamCommandPassDirection::Out)
226       .Cases("[in,out]", "[out,in]", ParamCommandPassDirection::InOut)
227       .Default(static_cast<ParamCommandPassDirection>(-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   ParamCommandPassDirection Direction = getParamPassDirection(ArgLower);
236 
237   if (Direction == static_cast<ParamCommandPassDirection>(-1)) {
238     // Try again with whitespace removed.
239     llvm::erase_if(ArgLower, clang::isWhitespace);
240     Direction = getParamPassDirection(ArgLower);
241 
242     SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
243     if (Direction != static_cast<ParamCommandPassDirection>(-1)) {
244       const char *FixedName =
245           ParamCommandComment::getDirectionAsString(Direction);
246       Diag(ArgLocBegin, diag::warn_doc_param_spaces_in_direction)
247           << ArgRange << FixItHint::CreateReplacement(ArgRange, FixedName);
248     } else {
249       Diag(ArgLocBegin, diag::warn_doc_param_invalid_direction) << ArgRange;
250       Direction = ParamCommandPassDirection::In; // Sane fall back.
251     }
252   }
253   Command->setDirection(Direction,
254                         /*Explicit=*/true);
255 }
256 
257 void Sema::actOnParamCommandParamNameArg(ParamCommandComment *Command,
258                                          SourceLocation ArgLocBegin,
259                                          SourceLocation ArgLocEnd,
260                                          StringRef Arg) {
261   // Parser will not feed us more arguments than needed.
262   assert(Command->getNumArgs() == 0);
263 
264   if (!Command->isDirectionExplicit()) {
265     // User didn't provide a direction argument.
266     Command->setDirection(ParamCommandPassDirection::In,
267                           /* Explicit = */ false);
268   }
269   auto *A = new (Allocator)
270       Comment::Argument{SourceRange(ArgLocBegin, ArgLocEnd), Arg};
271   Command->setArgs(llvm::ArrayRef(A, 1));
272 }
273 
274 void Sema::actOnParamCommandFinish(ParamCommandComment *Command,
275                                    ParagraphComment *Paragraph) {
276   Command->setParagraph(Paragraph);
277   checkBlockCommandEmptyParagraph(Command);
278 }
279 
280 TParamCommandComment *Sema::actOnTParamCommandStart(
281                                       SourceLocation LocBegin,
282                                       SourceLocation LocEnd,
283                                       unsigned CommandID,
284                                       CommandMarkerKind CommandMarker) {
285   TParamCommandComment *Command =
286       new (Allocator) TParamCommandComment(LocBegin, LocEnd, CommandID,
287                                            CommandMarker);
288 
289   if (!isTemplateOrSpecialization())
290     Diag(Command->getLocation(),
291          diag::warn_doc_tparam_not_attached_to_a_template_decl)
292       << CommandMarker
293       << Command->getCommandNameRange(Traits);
294 
295   return Command;
296 }
297 
298 void Sema::actOnTParamCommandParamNameArg(TParamCommandComment *Command,
299                                           SourceLocation ArgLocBegin,
300                                           SourceLocation ArgLocEnd,
301                                           StringRef Arg) {
302   // Parser will not feed us more arguments than needed.
303   assert(Command->getNumArgs() == 0);
304 
305   auto *A = new (Allocator)
306       Comment::Argument{SourceRange(ArgLocBegin, ArgLocEnd), Arg};
307   Command->setArgs(llvm::ArrayRef(A, 1));
308 
309   if (!isTemplateOrSpecialization()) {
310     // We already warned that this \\tparam is not attached to a template decl.
311     return;
312   }
313 
314   const TemplateParameterList *TemplateParameters =
315       ThisDeclInfo->TemplateParameters;
316   SmallVector<unsigned, 2> Position;
317   if (resolveTParamReference(Arg, TemplateParameters, &Position)) {
318     Command->setPosition(copyArray(llvm::ArrayRef(Position)));
319     TParamCommandComment *&PrevCommand = TemplateParameterDocs[Arg];
320     if (PrevCommand) {
321       SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
322       Diag(ArgLocBegin, diag::warn_doc_tparam_duplicate)
323         << Arg << ArgRange;
324       Diag(PrevCommand->getLocation(), diag::note_doc_tparam_previous)
325         << PrevCommand->getParamNameRange();
326     }
327     PrevCommand = Command;
328     return;
329   }
330 
331   SourceRange ArgRange(ArgLocBegin, ArgLocEnd);
332   Diag(ArgLocBegin, diag::warn_doc_tparam_not_found)
333     << Arg << ArgRange;
334 
335   if (!TemplateParameters || TemplateParameters->size() == 0)
336     return;
337 
338   StringRef CorrectedName;
339   if (TemplateParameters->size() == 1) {
340     const NamedDecl *Param = TemplateParameters->getParam(0);
341     const IdentifierInfo *II = Param->getIdentifier();
342     if (II)
343       CorrectedName = II->getName();
344   } else {
345     CorrectedName = correctTypoInTParamReference(Arg, TemplateParameters);
346   }
347 
348   if (!CorrectedName.empty()) {
349     Diag(ArgLocBegin, diag::note_doc_tparam_name_suggestion)
350       << CorrectedName
351       << FixItHint::CreateReplacement(ArgRange, CorrectedName);
352   }
353 }
354 
355 void Sema::actOnTParamCommandFinish(TParamCommandComment *Command,
356                                     ParagraphComment *Paragraph) {
357   Command->setParagraph(Paragraph);
358   checkBlockCommandEmptyParagraph(Command);
359 }
360 
361 InlineCommandComment *
362 Sema::actOnInlineCommand(SourceLocation CommandLocBegin,
363                          SourceLocation CommandLocEnd, unsigned CommandID,
364                          ArrayRef<Comment::Argument> Args) {
365   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
366 
367   return new (Allocator)
368       InlineCommandComment(CommandLocBegin, CommandLocEnd, CommandID,
369                            getInlineCommandRenderKind(CommandName), Args);
370 }
371 
372 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
373                                                 SourceLocation LocEnd,
374                                                 StringRef CommandName) {
375   unsigned CommandID = Traits.registerUnknownCommand(CommandName)->getID();
376   return actOnUnknownCommand(LocBegin, LocEnd, CommandID);
377 }
378 
379 InlineContentComment *Sema::actOnUnknownCommand(SourceLocation LocBegin,
380                                                 SourceLocation LocEnd,
381                                                 unsigned CommandID) {
382   ArrayRef<InlineCommandComment::Argument> Args;
383   return new (Allocator) InlineCommandComment(
384       LocBegin, LocEnd, CommandID, InlineCommandRenderKind::Normal, Args);
385 }
386 
387 TextComment *Sema::actOnText(SourceLocation LocBegin,
388                              SourceLocation LocEnd,
389                              StringRef Text) {
390   return new (Allocator) TextComment(LocBegin, LocEnd, Text);
391 }
392 
393 VerbatimBlockComment *Sema::actOnVerbatimBlockStart(SourceLocation Loc,
394                                                     unsigned CommandID) {
395   StringRef CommandName = Traits.getCommandInfo(CommandID)->Name;
396   return new (Allocator) VerbatimBlockComment(
397                                   Loc,
398                                   Loc.getLocWithOffset(1 + CommandName.size()),
399                                   CommandID);
400 }
401 
402 VerbatimBlockLineComment *Sema::actOnVerbatimBlockLine(SourceLocation Loc,
403                                                        StringRef Text) {
404   return new (Allocator) VerbatimBlockLineComment(Loc, Text);
405 }
406 
407 void Sema::actOnVerbatimBlockFinish(
408                             VerbatimBlockComment *Block,
409                             SourceLocation CloseNameLocBegin,
410                             StringRef CloseName,
411                             ArrayRef<VerbatimBlockLineComment *> Lines) {
412   Block->setCloseName(CloseName, CloseNameLocBegin);
413   Block->setLines(Lines);
414 }
415 
416 VerbatimLineComment *Sema::actOnVerbatimLine(SourceLocation LocBegin,
417                                              unsigned CommandID,
418                                              SourceLocation TextBegin,
419                                              StringRef Text) {
420   VerbatimLineComment *VL = new (Allocator) VerbatimLineComment(
421                               LocBegin,
422                               TextBegin.getLocWithOffset(Text.size()),
423                               CommandID,
424                               TextBegin,
425                               Text);
426   checkFunctionDeclVerbatimLine(VL);
427   checkContainerDeclVerbatimLine(VL);
428   return VL;
429 }
430 
431 HTMLStartTagComment *Sema::actOnHTMLStartTagStart(SourceLocation LocBegin,
432                                                   StringRef TagName) {
433   return new (Allocator) HTMLStartTagComment(LocBegin, TagName);
434 }
435 
436 void Sema::actOnHTMLStartTagFinish(
437                               HTMLStartTagComment *Tag,
438                               ArrayRef<HTMLStartTagComment::Attribute> Attrs,
439                               SourceLocation GreaterLoc,
440                               bool IsSelfClosing) {
441   Tag->setAttrs(Attrs);
442   Tag->setGreaterLoc(GreaterLoc);
443   if (IsSelfClosing)
444     Tag->setSelfClosing();
445   else if (!isHTMLEndTagForbidden(Tag->getTagName()))
446     HTMLOpenTags.push_back(Tag);
447 }
448 
449 HTMLEndTagComment *Sema::actOnHTMLEndTag(SourceLocation LocBegin,
450                                          SourceLocation LocEnd,
451                                          StringRef TagName) {
452   HTMLEndTagComment *HET =
453       new (Allocator) HTMLEndTagComment(LocBegin, LocEnd, TagName);
454   if (isHTMLEndTagForbidden(TagName)) {
455     Diag(HET->getLocation(), diag::warn_doc_html_end_forbidden)
456       << TagName << HET->getSourceRange();
457     HET->setIsMalformed();
458     return HET;
459   }
460 
461   bool FoundOpen = false;
462   for (SmallVectorImpl<HTMLStartTagComment *>::const_reverse_iterator
463        I = HTMLOpenTags.rbegin(), E = HTMLOpenTags.rend();
464        I != E; ++I) {
465     if ((*I)->getTagName() == TagName) {
466       FoundOpen = true;
467       break;
468     }
469   }
470   if (!FoundOpen) {
471     Diag(HET->getLocation(), diag::warn_doc_html_end_unbalanced)
472       << HET->getSourceRange();
473     HET->setIsMalformed();
474     return HET;
475   }
476 
477   while (!HTMLOpenTags.empty()) {
478     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
479     StringRef LastNotClosedTagName = HST->getTagName();
480     if (LastNotClosedTagName == TagName) {
481       // If the start tag is malformed, end tag is malformed as well.
482       if (HST->isMalformed())
483         HET->setIsMalformed();
484       break;
485     }
486 
487     if (isHTMLEndTagOptional(LastNotClosedTagName))
488       continue;
489 
490     bool OpenLineInvalid;
491     const unsigned OpenLine = SourceMgr.getPresumedLineNumber(
492                                                 HST->getLocation(),
493                                                 &OpenLineInvalid);
494     bool CloseLineInvalid;
495     const unsigned CloseLine = SourceMgr.getPresumedLineNumber(
496                                                 HET->getLocation(),
497                                                 &CloseLineInvalid);
498 
499     if (OpenLineInvalid || CloseLineInvalid || OpenLine == CloseLine) {
500       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
501         << HST->getTagName() << HET->getTagName()
502         << HST->getSourceRange() << HET->getSourceRange();
503       HST->setIsMalformed();
504     } else {
505       Diag(HST->getLocation(), diag::warn_doc_html_start_end_mismatch)
506         << HST->getTagName() << HET->getTagName()
507         << HST->getSourceRange();
508       Diag(HET->getLocation(), diag::note_doc_html_end_tag)
509         << HET->getSourceRange();
510       HST->setIsMalformed();
511     }
512   }
513 
514   return HET;
515 }
516 
517 FullComment *Sema::actOnFullComment(
518                               ArrayRef<BlockContentComment *> Blocks) {
519   FullComment *FC = new (Allocator) FullComment(Blocks, ThisDeclInfo);
520   resolveParamCommandIndexes(FC);
521 
522   // Complain about HTML tags that are not closed.
523   while (!HTMLOpenTags.empty()) {
524     HTMLStartTagComment *HST = HTMLOpenTags.pop_back_val();
525     if (isHTMLEndTagOptional(HST->getTagName()))
526       continue;
527 
528     Diag(HST->getLocation(), diag::warn_doc_html_missing_end_tag)
529       << HST->getTagName() << HST->getSourceRange();
530     HST->setIsMalformed();
531   }
532 
533   return FC;
534 }
535 
536 void Sema::checkBlockCommandEmptyParagraph(BlockCommandComment *Command) {
537   if (Traits.getCommandInfo(Command->getCommandID())->IsEmptyParagraphAllowed)
538     return;
539 
540   ParagraphComment *Paragraph = Command->getParagraph();
541   if (Paragraph->isWhitespace()) {
542     SourceLocation DiagLoc;
543     if (Command->getNumArgs() > 0)
544       DiagLoc = Command->getArgRange(Command->getNumArgs() - 1).getEnd();
545     if (!DiagLoc.isValid())
546       DiagLoc = Command->getCommandNameRange(Traits).getEnd();
547     Diag(DiagLoc, diag::warn_doc_block_command_empty_paragraph)
548       << Command->getCommandMarker()
549       << Command->getCommandName(Traits)
550       << Command->getSourceRange();
551   }
552 }
553 
554 void Sema::checkReturnsCommand(const BlockCommandComment *Command) {
555   if (!Traits.getCommandInfo(Command->getCommandID())->IsReturnsCommand)
556     return;
557 
558   assert(ThisDeclInfo && "should not call this check on a bare comment");
559 
560   // We allow the return command for all @properties because it can be used
561   // to document the value that the property getter returns.
562   if (isObjCPropertyDecl())
563     return;
564   if (involvesFunctionType()) {
565     assert(!ThisDeclInfo->ReturnType.isNull() &&
566            "should have a valid return type");
567     if (ThisDeclInfo->ReturnType->isVoidType()) {
568       unsigned DiagKind;
569       switch (ThisDeclInfo->CommentDecl->getKind()) {
570       default:
571         if (ThisDeclInfo->IsObjCMethod)
572           DiagKind = 3;
573         else
574           DiagKind = 0;
575         break;
576       case Decl::CXXConstructor:
577         DiagKind = 1;
578         break;
579       case Decl::CXXDestructor:
580         DiagKind = 2;
581         break;
582       }
583       Diag(Command->getLocation(),
584            diag::warn_doc_returns_attached_to_a_void_function)
585         << Command->getCommandMarker()
586         << Command->getCommandName(Traits)
587         << DiagKind
588         << Command->getSourceRange();
589     }
590     return;
591   }
592 
593   Diag(Command->getLocation(),
594        diag::warn_doc_returns_not_attached_to_a_function_decl)
595     << Command->getCommandMarker()
596     << Command->getCommandName(Traits)
597     << Command->getSourceRange();
598 }
599 
600 void Sema::checkBlockCommandDuplicate(const BlockCommandComment *Command) {
601   const CommandInfo *Info = Traits.getCommandInfo(Command->getCommandID());
602   const BlockCommandComment *PrevCommand = nullptr;
603   if (Info->IsBriefCommand) {
604     if (!BriefCommand) {
605       BriefCommand = Command;
606       return;
607     }
608     PrevCommand = BriefCommand;
609   } else if (Info->IsHeaderfileCommand) {
610     if (!HeaderfileCommand) {
611       HeaderfileCommand = Command;
612       return;
613     }
614     PrevCommand = HeaderfileCommand;
615   } else {
616     // We don't want to check this command for duplicates.
617     return;
618   }
619   StringRef CommandName = Command->getCommandName(Traits);
620   StringRef PrevCommandName = PrevCommand->getCommandName(Traits);
621   Diag(Command->getLocation(), diag::warn_doc_block_command_duplicate)
622       << Command->getCommandMarker()
623       << CommandName
624       << Command->getSourceRange();
625   if (CommandName == PrevCommandName)
626     Diag(PrevCommand->getLocation(), diag::note_doc_block_command_previous)
627         << PrevCommand->getCommandMarker()
628         << PrevCommandName
629         << PrevCommand->getSourceRange();
630   else
631     Diag(PrevCommand->getLocation(),
632          diag::note_doc_block_command_previous_alias)
633         << PrevCommand->getCommandMarker()
634         << PrevCommandName
635         << CommandName;
636 }
637 
638 void Sema::checkDeprecatedCommand(const BlockCommandComment *Command) {
639   if (!Traits.getCommandInfo(Command->getCommandID())->IsDeprecatedCommand)
640     return;
641 
642   assert(ThisDeclInfo && "should not call this check on a bare comment");
643 
644   const Decl *D = ThisDeclInfo->CommentDecl;
645   if (!D)
646     return;
647 
648   if (D->hasAttr<DeprecatedAttr>() ||
649       D->hasAttr<AvailabilityAttr>() ||
650       D->hasAttr<UnavailableAttr>())
651     return;
652 
653   Diag(Command->getLocation(), diag::warn_doc_deprecated_not_sync)
654       << Command->getSourceRange() << Command->getCommandMarker();
655 
656   // Try to emit a fixit with a deprecation attribute.
657   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
658     // Don't emit a Fix-It for non-member function definitions.  GCC does not
659     // accept attributes on them.
660     const DeclContext *Ctx = FD->getDeclContext();
661     if ((!Ctx || !Ctx->isRecord()) &&
662         FD->doesThisDeclarationHaveABody())
663       return;
664 
665     const LangOptions &LO = FD->getLangOpts();
666     const bool DoubleSquareBracket = LO.CPlusPlus14 || LO.C23;
667     StringRef AttributeSpelling =
668         DoubleSquareBracket ? "[[deprecated]]" : "__attribute__((deprecated))";
669     if (PP) {
670       // Try to find a replacement macro:
671       // - In C23/C++14 we prefer [[deprecated]].
672       // - If not found or an older C/C++ look for __attribute__((deprecated)).
673       StringRef MacroName;
674       if (DoubleSquareBracket) {
675         TokenValue Tokens[] = {tok::l_square, tok::l_square,
676                                PP->getIdentifierInfo("deprecated"),
677                                tok::r_square, tok::r_square};
678         MacroName = PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
679         if (!MacroName.empty())
680           AttributeSpelling = MacroName;
681       }
682 
683       if (MacroName.empty()) {
684         TokenValue Tokens[] = {
685             tok::kw___attribute, tok::l_paren,
686             tok::l_paren,        PP->getIdentifierInfo("deprecated"),
687             tok::r_paren,        tok::r_paren};
688         StringRef MacroName =
689             PP->getLastMacroWithSpelling(FD->getLocation(), Tokens);
690         if (!MacroName.empty())
691           AttributeSpelling = MacroName;
692       }
693     }
694 
695     SmallString<64> TextToInsert = AttributeSpelling;
696     TextToInsert += " ";
697     SourceLocation Loc = FD->getSourceRange().getBegin();
698     Diag(Loc, diag::note_add_deprecation_attr)
699         << FixItHint::CreateInsertion(Loc, TextToInsert);
700   }
701 }
702 
703 void Sema::resolveParamCommandIndexes(const FullComment *FC) {
704   if (!involvesFunctionType()) {
705     // We already warned that \\param commands are not attached to a function
706     // decl.
707     return;
708   }
709 
710   SmallVector<ParamCommandComment *, 8> UnresolvedParamCommands;
711 
712   // Comment AST nodes that correspond to \c ParamVars for which we have
713   // found a \\param command or NULL if no documentation was found so far.
714   SmallVector<ParamCommandComment *, 8> ParamVarDocs;
715 
716   ArrayRef<const ParmVarDecl *> ParamVars = getParamVars();
717   ParamVarDocs.resize(ParamVars.size(), nullptr);
718 
719   // First pass over all \\param commands: resolve all parameter names.
720   for (Comment::child_iterator I = FC->child_begin(), E = FC->child_end();
721        I != E; ++I) {
722     ParamCommandComment *PCC = dyn_cast<ParamCommandComment>(*I);
723     if (!PCC || !PCC->hasParamName())
724       continue;
725     StringRef ParamName = PCC->getParamNameAsWritten();
726 
727     // Check that referenced parameter name is in the function decl.
728     const unsigned ResolvedParamIndex = resolveParmVarReference(ParamName,
729                                                                 ParamVars);
730     if (ResolvedParamIndex == ParamCommandComment::VarArgParamIndex) {
731       PCC->setIsVarArgParam();
732       continue;
733     }
734     if (ResolvedParamIndex == ParamCommandComment::InvalidParamIndex) {
735       UnresolvedParamCommands.push_back(PCC);
736       continue;
737     }
738     PCC->setParamIndex(ResolvedParamIndex);
739     if (ParamVarDocs[ResolvedParamIndex]) {
740       SourceRange ArgRange = PCC->getParamNameRange();
741       Diag(ArgRange.getBegin(), diag::warn_doc_param_duplicate)
742         << ParamName << ArgRange;
743       ParamCommandComment *PrevCommand = ParamVarDocs[ResolvedParamIndex];
744       Diag(PrevCommand->getLocation(), diag::note_doc_param_previous)
745         << PrevCommand->getParamNameRange();
746     }
747     ParamVarDocs[ResolvedParamIndex] = PCC;
748   }
749 
750   // Find parameter declarations that have no corresponding \\param.
751   SmallVector<const ParmVarDecl *, 8> OrphanedParamDecls;
752   for (unsigned i = 0, e = ParamVarDocs.size(); i != e; ++i) {
753     if (!ParamVarDocs[i])
754       OrphanedParamDecls.push_back(ParamVars[i]);
755   }
756 
757   // Second pass over unresolved \\param commands: do typo correction.
758   // Suggest corrections from a set of parameter declarations that have no
759   // corresponding \\param.
760   for (unsigned i = 0, e = UnresolvedParamCommands.size(); i != e; ++i) {
761     const ParamCommandComment *PCC = UnresolvedParamCommands[i];
762 
763     SourceRange ArgRange = PCC->getParamNameRange();
764     StringRef ParamName = PCC->getParamNameAsWritten();
765     Diag(ArgRange.getBegin(), diag::warn_doc_param_not_found)
766       << ParamName << ArgRange;
767 
768     // All parameters documented -- can't suggest a correction.
769     if (OrphanedParamDecls.size() == 0)
770       continue;
771 
772     unsigned CorrectedParamIndex = ParamCommandComment::InvalidParamIndex;
773     if (OrphanedParamDecls.size() == 1) {
774       // If one parameter is not documented then that parameter is the only
775       // possible suggestion.
776       CorrectedParamIndex = 0;
777     } else {
778       // Do typo correction.
779       CorrectedParamIndex = correctTypoInParmVarReference(ParamName,
780                                                           OrphanedParamDecls);
781     }
782     if (CorrectedParamIndex != ParamCommandComment::InvalidParamIndex) {
783       const ParmVarDecl *CorrectedPVD = OrphanedParamDecls[CorrectedParamIndex];
784       if (const IdentifierInfo *CorrectedII = CorrectedPVD->getIdentifier())
785         Diag(ArgRange.getBegin(), diag::note_doc_param_name_suggestion)
786           << CorrectedII->getName()
787           << FixItHint::CreateReplacement(ArgRange, CorrectedII->getName());
788     }
789   }
790 }
791 
792 bool Sema::involvesFunctionType() {
793   if (!ThisDeclInfo)
794     return false;
795   if (!ThisDeclInfo->IsFilled)
796     inspectThisDecl();
797   return ThisDeclInfo->involvesFunctionType();
798 }
799 
800 bool Sema::isFunctionDecl() {
801   if (!ThisDeclInfo)
802     return false;
803   if (!ThisDeclInfo->IsFilled)
804     inspectThisDecl();
805   return ThisDeclInfo->getKind() == DeclInfo::FunctionKind;
806 }
807 
808 bool Sema::isAnyFunctionDecl() {
809   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
810          isa<FunctionDecl>(ThisDeclInfo->CurrentDecl);
811 }
812 
813 bool Sema::isFunctionOrMethodVariadic() {
814   if (!ThisDeclInfo)
815     return false;
816   if (!ThisDeclInfo->IsFilled)
817     inspectThisDecl();
818   return ThisDeclInfo->IsVariadic;
819 }
820 
821 bool Sema::isObjCMethodDecl() {
822   return isFunctionDecl() && ThisDeclInfo->CurrentDecl &&
823          isa<ObjCMethodDecl>(ThisDeclInfo->CurrentDecl);
824 }
825 
826 bool Sema::isFunctionPointerVarDecl() {
827   if (!ThisDeclInfo)
828     return false;
829   if (!ThisDeclInfo->IsFilled)
830     inspectThisDecl();
831   if (ThisDeclInfo->getKind() == DeclInfo::VariableKind) {
832     if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(ThisDeclInfo->CurrentDecl)) {
833       QualType QT = VD->getType();
834       return QT->isFunctionPointerType();
835     }
836   }
837   return false;
838 }
839 
840 bool Sema::isObjCPropertyDecl() {
841   if (!ThisDeclInfo)
842     return false;
843   if (!ThisDeclInfo->IsFilled)
844     inspectThisDecl();
845   return ThisDeclInfo->CurrentDecl->getKind() == Decl::ObjCProperty;
846 }
847 
848 bool Sema::isTemplateOrSpecialization() {
849   if (!ThisDeclInfo)
850     return false;
851   if (!ThisDeclInfo->IsFilled)
852     inspectThisDecl();
853   return ThisDeclInfo->getTemplateKind() != DeclInfo::NotTemplate;
854 }
855 
856 bool Sema::isRecordLikeDecl() {
857   if (!ThisDeclInfo)
858     return false;
859   if (!ThisDeclInfo->IsFilled)
860     inspectThisDecl();
861   return isUnionDecl() || isClassOrStructDecl() || isObjCInterfaceDecl() ||
862          isObjCProtocolDecl();
863 }
864 
865 bool Sema::isUnionDecl() {
866   if (!ThisDeclInfo)
867     return false;
868   if (!ThisDeclInfo->IsFilled)
869     inspectThisDecl();
870   if (const RecordDecl *RD =
871         dyn_cast_or_null<RecordDecl>(ThisDeclInfo->CurrentDecl))
872     return RD->isUnion();
873   return false;
874 }
875 static bool isClassOrStructDeclImpl(const Decl *D) {
876   if (auto *record = dyn_cast_or_null<RecordDecl>(D))
877     return !record->isUnion();
878 
879   return false;
880 }
881 
882 bool Sema::isClassOrStructDecl() {
883   if (!ThisDeclInfo)
884     return false;
885   if (!ThisDeclInfo->IsFilled)
886     inspectThisDecl();
887 
888   if (!ThisDeclInfo->CurrentDecl)
889     return false;
890 
891   return isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl);
892 }
893 
894 bool Sema::isClassOrStructOrTagTypedefDecl() {
895   if (!ThisDeclInfo)
896     return false;
897   if (!ThisDeclInfo->IsFilled)
898     inspectThisDecl();
899 
900   if (!ThisDeclInfo->CurrentDecl)
901     return false;
902 
903   if (isClassOrStructDeclImpl(ThisDeclInfo->CurrentDecl))
904     return true;
905 
906   if (auto *ThisTypedefDecl = dyn_cast<TypedefDecl>(ThisDeclInfo->CurrentDecl)) {
907     auto UnderlyingType = ThisTypedefDecl->getUnderlyingType();
908     if (auto ThisElaboratedType = dyn_cast<ElaboratedType>(UnderlyingType)) {
909       auto DesugaredType = ThisElaboratedType->desugar();
910       if (auto *DesugaredTypePtr = DesugaredType.getTypePtrOrNull()) {
911         if (auto *ThisRecordType = dyn_cast<RecordType>(DesugaredTypePtr)) {
912           return isClassOrStructDeclImpl(ThisRecordType->getAsRecordDecl());
913         }
914       }
915     }
916   }
917 
918   return false;
919 }
920 
921 bool Sema::isClassTemplateDecl() {
922   if (!ThisDeclInfo)
923     return false;
924   if (!ThisDeclInfo->IsFilled)
925     inspectThisDecl();
926   return ThisDeclInfo->CurrentDecl &&
927           (isa<ClassTemplateDecl>(ThisDeclInfo->CurrentDecl));
928 }
929 
930 bool Sema::isFunctionTemplateDecl() {
931   if (!ThisDeclInfo)
932     return false;
933   if (!ThisDeclInfo->IsFilled)
934     inspectThisDecl();
935   return ThisDeclInfo->CurrentDecl &&
936          (isa<FunctionTemplateDecl>(ThisDeclInfo->CurrentDecl));
937 }
938 
939 bool Sema::isObjCInterfaceDecl() {
940   if (!ThisDeclInfo)
941     return false;
942   if (!ThisDeclInfo->IsFilled)
943     inspectThisDecl();
944   return ThisDeclInfo->CurrentDecl &&
945          isa<ObjCInterfaceDecl>(ThisDeclInfo->CurrentDecl);
946 }
947 
948 bool Sema::isObjCProtocolDecl() {
949   if (!ThisDeclInfo)
950     return false;
951   if (!ThisDeclInfo->IsFilled)
952     inspectThisDecl();
953   return ThisDeclInfo->CurrentDecl &&
954          isa<ObjCProtocolDecl>(ThisDeclInfo->CurrentDecl);
955 }
956 
957 ArrayRef<const ParmVarDecl *> Sema::getParamVars() {
958   if (!ThisDeclInfo->IsFilled)
959     inspectThisDecl();
960   return ThisDeclInfo->ParamVars;
961 }
962 
963 void Sema::inspectThisDecl() {
964   ThisDeclInfo->fill();
965 }
966 
967 unsigned Sema::resolveParmVarReference(StringRef Name,
968                                        ArrayRef<const ParmVarDecl *> ParamVars) {
969   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i) {
970     const IdentifierInfo *II = ParamVars[i]->getIdentifier();
971     if (II && II->getName() == Name)
972       return i;
973   }
974   if (Name == "..." && isFunctionOrMethodVariadic())
975     return ParamCommandComment::VarArgParamIndex;
976   return ParamCommandComment::InvalidParamIndex;
977 }
978 
979 namespace {
980 class SimpleTypoCorrector {
981   const NamedDecl *BestDecl;
982 
983   StringRef Typo;
984   const unsigned MaxEditDistance;
985 
986   unsigned BestEditDistance;
987   unsigned BestIndex;
988   unsigned NextIndex;
989 
990 public:
991   explicit SimpleTypoCorrector(StringRef Typo)
992       : BestDecl(nullptr), Typo(Typo), MaxEditDistance((Typo.size() + 2) / 3),
993         BestEditDistance(MaxEditDistance + 1), BestIndex(0), NextIndex(0) {}
994 
995   void addDecl(const NamedDecl *ND);
996 
997   const NamedDecl *getBestDecl() const {
998     if (BestEditDistance > MaxEditDistance)
999       return nullptr;
1000 
1001     return BestDecl;
1002   }
1003 
1004   unsigned getBestDeclIndex() const {
1005     assert(getBestDecl());
1006     return BestIndex;
1007   }
1008 };
1009 
1010 void SimpleTypoCorrector::addDecl(const NamedDecl *ND) {
1011   unsigned CurrIndex = NextIndex++;
1012 
1013   const IdentifierInfo *II = ND->getIdentifier();
1014   if (!II)
1015     return;
1016 
1017   StringRef Name = II->getName();
1018   unsigned MinPossibleEditDistance = abs((int)Name.size() - (int)Typo.size());
1019   if (MinPossibleEditDistance > 0 &&
1020       Typo.size() / MinPossibleEditDistance < 3)
1021     return;
1022 
1023   unsigned EditDistance = Typo.edit_distance(Name, true, MaxEditDistance);
1024   if (EditDistance < BestEditDistance) {
1025     BestEditDistance = EditDistance;
1026     BestDecl = ND;
1027     BestIndex = CurrIndex;
1028   }
1029 }
1030 } // end anonymous namespace
1031 
1032 unsigned Sema::correctTypoInParmVarReference(
1033                                     StringRef Typo,
1034                                     ArrayRef<const ParmVarDecl *> ParamVars) {
1035   SimpleTypoCorrector Corrector(Typo);
1036   for (unsigned i = 0, e = ParamVars.size(); i != e; ++i)
1037     Corrector.addDecl(ParamVars[i]);
1038   if (Corrector.getBestDecl())
1039     return Corrector.getBestDeclIndex();
1040   else
1041     return ParamCommandComment::InvalidParamIndex;
1042 }
1043 
1044 namespace {
1045 bool ResolveTParamReferenceHelper(
1046                             StringRef Name,
1047                             const TemplateParameterList *TemplateParameters,
1048                             SmallVectorImpl<unsigned> *Position) {
1049   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1050     const NamedDecl *Param = TemplateParameters->getParam(i);
1051     const IdentifierInfo *II = Param->getIdentifier();
1052     if (II && II->getName() == Name) {
1053       Position->push_back(i);
1054       return true;
1055     }
1056 
1057     if (const TemplateTemplateParmDecl *TTP =
1058             dyn_cast<TemplateTemplateParmDecl>(Param)) {
1059       Position->push_back(i);
1060       if (ResolveTParamReferenceHelper(Name, TTP->getTemplateParameters(),
1061                                        Position))
1062         return true;
1063       Position->pop_back();
1064     }
1065   }
1066   return false;
1067 }
1068 } // end anonymous namespace
1069 
1070 bool Sema::resolveTParamReference(
1071                             StringRef Name,
1072                             const TemplateParameterList *TemplateParameters,
1073                             SmallVectorImpl<unsigned> *Position) {
1074   Position->clear();
1075   if (!TemplateParameters)
1076     return false;
1077 
1078   return ResolveTParamReferenceHelper(Name, TemplateParameters, Position);
1079 }
1080 
1081 namespace {
1082 void CorrectTypoInTParamReferenceHelper(
1083                             const TemplateParameterList *TemplateParameters,
1084                             SimpleTypoCorrector &Corrector) {
1085   for (unsigned i = 0, e = TemplateParameters->size(); i != e; ++i) {
1086     const NamedDecl *Param = TemplateParameters->getParam(i);
1087     Corrector.addDecl(Param);
1088 
1089     if (const TemplateTemplateParmDecl *TTP =
1090             dyn_cast<TemplateTemplateParmDecl>(Param))
1091       CorrectTypoInTParamReferenceHelper(TTP->getTemplateParameters(),
1092                                          Corrector);
1093   }
1094 }
1095 } // end anonymous namespace
1096 
1097 StringRef Sema::correctTypoInTParamReference(
1098                             StringRef Typo,
1099                             const TemplateParameterList *TemplateParameters) {
1100   SimpleTypoCorrector Corrector(Typo);
1101   CorrectTypoInTParamReferenceHelper(TemplateParameters, Corrector);
1102   if (const NamedDecl *ND = Corrector.getBestDecl()) {
1103     const IdentifierInfo *II = ND->getIdentifier();
1104     assert(II && "SimpleTypoCorrector should not return this decl");
1105     return II->getName();
1106   }
1107   return StringRef();
1108 }
1109 
1110 InlineCommandRenderKind Sema::getInlineCommandRenderKind(StringRef Name) const {
1111   assert(Traits.getCommandInfo(Name)->IsInlineCommand);
1112 
1113   return llvm::StringSwitch<InlineCommandRenderKind>(Name)
1114       .Case("b", InlineCommandRenderKind::Bold)
1115       .Cases("c", "p", InlineCommandRenderKind::Monospaced)
1116       .Cases("a", "e", "em", InlineCommandRenderKind::Emphasized)
1117       .Case("anchor", InlineCommandRenderKind::Anchor)
1118       .Default(InlineCommandRenderKind::Normal);
1119 }
1120 
1121 } // end namespace comments
1122 } // end namespace clang
1123