xref: /freebsd/contrib/llvm-project/clang/lib/Sema/CodeCompleteConsumer.cpp (revision 77013d11e6483b970af25e13c9b892075742f7e5) 
1 //===- CodeCompleteConsumer.cpp - Code Completion Interface ---------------===//
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 //  This file implements the CodeCompleteConsumer class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Sema/CodeCompleteConsumer.h"
14 #include "clang-c/Index.h"
15 #include "clang/AST/Decl.h"
16 #include "clang/AST/DeclBase.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/DeclTemplate.h"
19 #include "clang/AST/DeclarationName.h"
20 #include "clang/AST/Type.h"
21 #include "clang/Basic/IdentifierTable.h"
22 #include "clang/Lex/Preprocessor.h"
23 #include "clang/Sema/Sema.h"
24 #include "llvm/ADT/SmallString.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/StringExtras.h"
27 #include "llvm/ADT/StringRef.h"
28 #include "llvm/ADT/Twine.h"
29 #include "llvm/Support/Casting.h"
30 #include "llvm/Support/Compiler.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/FormatVariadic.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include <algorithm>
35 #include <cassert>
36 #include <cstdint>
37 #include <string>
38 
39 using namespace clang;
40 
41 //===----------------------------------------------------------------------===//
42 // Code completion context implementation
43 //===----------------------------------------------------------------------===//
44 
45 bool CodeCompletionContext::wantConstructorResults() const {
46   switch (CCKind) {
47   case CCC_Recovery:
48   case CCC_Statement:
49   case CCC_Expression:
50   case CCC_ObjCMessageReceiver:
51   case CCC_ParenthesizedExpression:
52   case CCC_Symbol:
53   case CCC_SymbolOrNewName:
54     return true;
55 
56   case CCC_TopLevel:
57   case CCC_ObjCInterface:
58   case CCC_ObjCImplementation:
59   case CCC_ObjCIvarList:
60   case CCC_ClassStructUnion:
61   case CCC_DotMemberAccess:
62   case CCC_ArrowMemberAccess:
63   case CCC_ObjCPropertyAccess:
64   case CCC_EnumTag:
65   case CCC_UnionTag:
66   case CCC_ClassOrStructTag:
67   case CCC_ObjCProtocolName:
68   case CCC_Namespace:
69   case CCC_Type:
70   case CCC_NewName:
71   case CCC_MacroName:
72   case CCC_MacroNameUse:
73   case CCC_PreprocessorExpression:
74   case CCC_PreprocessorDirective:
75   case CCC_NaturalLanguage:
76   case CCC_SelectorName:
77   case CCC_TypeQualifiers:
78   case CCC_Other:
79   case CCC_OtherWithMacros:
80   case CCC_ObjCInstanceMessage:
81   case CCC_ObjCClassMessage:
82   case CCC_ObjCInterfaceName:
83   case CCC_ObjCCategoryName:
84   case CCC_IncludedFile:
85     return false;
86   }
87 
88   llvm_unreachable("Invalid CodeCompletionContext::Kind!");
89 }
90 
91 StringRef clang::getCompletionKindString(CodeCompletionContext::Kind Kind) {
92   using CCKind = CodeCompletionContext::Kind;
93   switch (Kind) {
94   case CCKind::CCC_Other:
95     return "Other";
96   case CCKind::CCC_OtherWithMacros:
97     return "OtherWithMacros";
98   case CCKind::CCC_TopLevel:
99     return "TopLevel";
100   case CCKind::CCC_ObjCInterface:
101     return "ObjCInterface";
102   case CCKind::CCC_ObjCImplementation:
103     return "ObjCImplementation";
104   case CCKind::CCC_ObjCIvarList:
105     return "ObjCIvarList";
106   case CCKind::CCC_ClassStructUnion:
107     return "ClassStructUnion";
108   case CCKind::CCC_Statement:
109     return "Statement";
110   case CCKind::CCC_Expression:
111     return "Expression";
112   case CCKind::CCC_ObjCMessageReceiver:
113     return "ObjCMessageReceiver";
114   case CCKind::CCC_DotMemberAccess:
115     return "DotMemberAccess";
116   case CCKind::CCC_ArrowMemberAccess:
117     return "ArrowMemberAccess";
118   case CCKind::CCC_ObjCPropertyAccess:
119     return "ObjCPropertyAccess";
120   case CCKind::CCC_EnumTag:
121     return "EnumTag";
122   case CCKind::CCC_UnionTag:
123     return "UnionTag";
124   case CCKind::CCC_ClassOrStructTag:
125     return "ClassOrStructTag";
126   case CCKind::CCC_ObjCProtocolName:
127     return "ObjCProtocolName";
128   case CCKind::CCC_Namespace:
129     return "Namespace";
130   case CCKind::CCC_Type:
131     return "Type";
132   case CCKind::CCC_NewName:
133     return "NewName";
134   case CCKind::CCC_Symbol:
135     return "Symbol";
136   case CCKind::CCC_SymbolOrNewName:
137     return "SymbolOrNewName";
138   case CCKind::CCC_MacroName:
139     return "MacroName";
140   case CCKind::CCC_MacroNameUse:
141     return "MacroNameUse";
142   case CCKind::CCC_PreprocessorExpression:
143     return "PreprocessorExpression";
144   case CCKind::CCC_PreprocessorDirective:
145     return "PreprocessorDirective";
146   case CCKind::CCC_NaturalLanguage:
147     return "NaturalLanguage";
148   case CCKind::CCC_SelectorName:
149     return "SelectorName";
150   case CCKind::CCC_TypeQualifiers:
151     return "TypeQualifiers";
152   case CCKind::CCC_ParenthesizedExpression:
153     return "ParenthesizedExpression";
154   case CCKind::CCC_ObjCInstanceMessage:
155     return "ObjCInstanceMessage";
156   case CCKind::CCC_ObjCClassMessage:
157     return "ObjCClassMessage";
158   case CCKind::CCC_ObjCInterfaceName:
159     return "ObjCInterfaceName";
160   case CCKind::CCC_ObjCCategoryName:
161     return "ObjCCategoryName";
162   case CCKind::CCC_IncludedFile:
163     return "IncludedFile";
164   case CCKind::CCC_Recovery:
165     return "Recovery";
166   }
167   llvm_unreachable("Invalid CodeCompletionContext::Kind!");
168 }
169 
170 //===----------------------------------------------------------------------===//
171 // Code completion string implementation
172 //===----------------------------------------------------------------------===//
173 
174 CodeCompletionString::Chunk::Chunk(ChunkKind Kind, const char *Text)
175     : Kind(Kind), Text("") {
176   switch (Kind) {
177   case CK_TypedText:
178   case CK_Text:
179   case CK_Placeholder:
180   case CK_Informative:
181   case CK_ResultType:
182   case CK_CurrentParameter:
183     this->Text = Text;
184     break;
185 
186   case CK_Optional:
187     llvm_unreachable("Optional strings cannot be created from text");
188 
189   case CK_LeftParen:
190     this->Text = "(";
191     break;
192 
193   case CK_RightParen:
194     this->Text = ")";
195     break;
196 
197   case CK_LeftBracket:
198     this->Text = "[";
199     break;
200 
201   case CK_RightBracket:
202     this->Text = "]";
203     break;
204 
205   case CK_LeftBrace:
206     this->Text = "{";
207     break;
208 
209   case CK_RightBrace:
210     this->Text = "}";
211     break;
212 
213   case CK_LeftAngle:
214     this->Text = "<";
215     break;
216 
217   case CK_RightAngle:
218     this->Text = ">";
219     break;
220 
221   case CK_Comma:
222     this->Text = ", ";
223     break;
224 
225   case CK_Colon:
226     this->Text = ":";
227     break;
228 
229   case CK_SemiColon:
230     this->Text = ";";
231     break;
232 
233   case CK_Equal:
234     this->Text = " = ";
235     break;
236 
237   case CK_HorizontalSpace:
238     this->Text = " ";
239     break;
240 
241   case CK_VerticalSpace:
242     this->Text = "\n";
243     break;
244   }
245 }
246 
247 CodeCompletionString::Chunk
248 CodeCompletionString::Chunk::CreateText(const char *Text) {
249   return Chunk(CK_Text, Text);
250 }
251 
252 CodeCompletionString::Chunk
253 CodeCompletionString::Chunk::CreateOptional(CodeCompletionString *Optional) {
254   Chunk Result;
255   Result.Kind = CK_Optional;
256   Result.Optional = Optional;
257   return Result;
258 }
259 
260 CodeCompletionString::Chunk
261 CodeCompletionString::Chunk::CreatePlaceholder(const char *Placeholder) {
262   return Chunk(CK_Placeholder, Placeholder);
263 }
264 
265 CodeCompletionString::Chunk
266 CodeCompletionString::Chunk::CreateInformative(const char *Informative) {
267   return Chunk(CK_Informative, Informative);
268 }
269 
270 CodeCompletionString::Chunk
271 CodeCompletionString::Chunk::CreateResultType(const char *ResultType) {
272   return Chunk(CK_ResultType, ResultType);
273 }
274 
275 CodeCompletionString::Chunk CodeCompletionString::Chunk::CreateCurrentParameter(
276     const char *CurrentParameter) {
277   return Chunk(CK_CurrentParameter, CurrentParameter);
278 }
279 
280 CodeCompletionString::CodeCompletionString(
281     const Chunk *Chunks, unsigned NumChunks, unsigned Priority,
282     CXAvailabilityKind Availability, const char **Annotations,
283     unsigned NumAnnotations, StringRef ParentName, const char *BriefComment)
284     : NumChunks(NumChunks), NumAnnotations(NumAnnotations), Priority(Priority),
285       Availability(Availability), ParentName(ParentName),
286       BriefComment(BriefComment) {
287   assert(NumChunks <= 0xffff);
288   assert(NumAnnotations <= 0xffff);
289 
290   Chunk *StoredChunks = reinterpret_cast<Chunk *>(this + 1);
291   for (unsigned I = 0; I != NumChunks; ++I)
292     StoredChunks[I] = Chunks[I];
293 
294   const char **StoredAnnotations =
295       reinterpret_cast<const char **>(StoredChunks + NumChunks);
296   for (unsigned I = 0; I != NumAnnotations; ++I)
297     StoredAnnotations[I] = Annotations[I];
298 }
299 
300 unsigned CodeCompletionString::getAnnotationCount() const {
301   return NumAnnotations;
302 }
303 
304 const char *CodeCompletionString::getAnnotation(unsigned AnnotationNr) const {
305   if (AnnotationNr < NumAnnotations)
306     return reinterpret_cast<const char *const *>(end())[AnnotationNr];
307   else
308     return nullptr;
309 }
310 
311 std::string CodeCompletionString::getAsString() const {
312   std::string Result;
313   llvm::raw_string_ostream OS(Result);
314 
315   for (const Chunk &C : *this) {
316     switch (C.Kind) {
317     case CK_Optional:
318       OS << "{#" << C.Optional->getAsString() << "#}";
319       break;
320     case CK_Placeholder:
321       OS << "<#" << C.Text << "#>";
322       break;
323     case CK_Informative:
324     case CK_ResultType:
325       OS << "[#" << C.Text << "#]";
326       break;
327     case CK_CurrentParameter:
328       OS << "<#" << C.Text << "#>";
329       break;
330     default:
331       OS << C.Text;
332       break;
333     }
334   }
335   return OS.str();
336 }
337 
338 const char *CodeCompletionString::getTypedText() const {
339   for (const Chunk &C : *this)
340     if (C.Kind == CK_TypedText)
341       return C.Text;
342 
343   return nullptr;
344 }
345 
346 const char *CodeCompletionAllocator::CopyString(const Twine &String) {
347   SmallString<128> Data;
348   StringRef Ref = String.toStringRef(Data);
349   // FIXME: It would be more efficient to teach Twine to tell us its size and
350   // then add a routine there to fill in an allocated char* with the contents
351   // of the string.
352   char *Mem = (char *)Allocate(Ref.size() + 1, 1);
353   std::copy(Ref.begin(), Ref.end(), Mem);
354   Mem[Ref.size()] = 0;
355   return Mem;
356 }
357 
358 StringRef CodeCompletionTUInfo::getParentName(const DeclContext *DC) {
359   if (!isa<NamedDecl>(DC))
360     return {};
361 
362   // Check whether we've already cached the parent name.
363   StringRef &CachedParentName = ParentNames[DC];
364   if (!CachedParentName.empty())
365     return CachedParentName;
366 
367   // If we already processed this DeclContext and assigned empty to it, the
368   // data pointer will be non-null.
369   if (CachedParentName.data() != nullptr)
370     return {};
371 
372   // Find the interesting names.
373   SmallVector<const DeclContext *, 2> Contexts;
374   while (DC && !DC->isFunctionOrMethod()) {
375     if (const auto *ND = dyn_cast<NamedDecl>(DC)) {
376       if (ND->getIdentifier())
377         Contexts.push_back(DC);
378     }
379 
380     DC = DC->getParent();
381   }
382 
383   {
384     SmallString<128> S;
385     llvm::raw_svector_ostream OS(S);
386     bool First = true;
387     for (unsigned I = Contexts.size(); I != 0; --I) {
388       if (First)
389         First = false;
390       else {
391         OS << "::";
392       }
393 
394       const DeclContext *CurDC = Contexts[I - 1];
395       if (const auto *CatImpl = dyn_cast<ObjCCategoryImplDecl>(CurDC))
396         CurDC = CatImpl->getCategoryDecl();
397 
398       if (const auto *Cat = dyn_cast<ObjCCategoryDecl>(CurDC)) {
399         const ObjCInterfaceDecl *Interface = Cat->getClassInterface();
400         if (!Interface) {
401           // Assign an empty StringRef but with non-null data to distinguish
402           // between empty because we didn't process the DeclContext yet.
403           CachedParentName = StringRef((const char *)(uintptr_t)~0U, 0);
404           return {};
405         }
406 
407         OS << Interface->getName() << '(' << Cat->getName() << ')';
408       } else {
409         OS << cast<NamedDecl>(CurDC)->getName();
410       }
411     }
412 
413     CachedParentName = AllocatorRef->CopyString(OS.str());
414   }
415 
416   return CachedParentName;
417 }
418 
419 CodeCompletionString *CodeCompletionBuilder::TakeString() {
420   void *Mem = getAllocator().Allocate(
421       sizeof(CodeCompletionString) + sizeof(Chunk) * Chunks.size() +
422           sizeof(const char *) * Annotations.size(),
423       alignof(CodeCompletionString));
424   CodeCompletionString *Result = new (Mem) CodeCompletionString(
425       Chunks.data(), Chunks.size(), Priority, Availability, Annotations.data(),
426       Annotations.size(), ParentName, BriefComment);
427   Chunks.clear();
428   return Result;
429 }
430 
431 void CodeCompletionBuilder::AddTypedTextChunk(const char *Text) {
432   Chunks.push_back(Chunk(CodeCompletionString::CK_TypedText, Text));
433 }
434 
435 void CodeCompletionBuilder::AddTextChunk(const char *Text) {
436   Chunks.push_back(Chunk::CreateText(Text));
437 }
438 
439 void CodeCompletionBuilder::AddOptionalChunk(CodeCompletionString *Optional) {
440   Chunks.push_back(Chunk::CreateOptional(Optional));
441 }
442 
443 void CodeCompletionBuilder::AddPlaceholderChunk(const char *Placeholder) {
444   Chunks.push_back(Chunk::CreatePlaceholder(Placeholder));
445 }
446 
447 void CodeCompletionBuilder::AddInformativeChunk(const char *Text) {
448   Chunks.push_back(Chunk::CreateInformative(Text));
449 }
450 
451 void CodeCompletionBuilder::AddResultTypeChunk(const char *ResultType) {
452   Chunks.push_back(Chunk::CreateResultType(ResultType));
453 }
454 
455 void CodeCompletionBuilder::AddCurrentParameterChunk(
456     const char *CurrentParameter) {
457   Chunks.push_back(Chunk::CreateCurrentParameter(CurrentParameter));
458 }
459 
460 void CodeCompletionBuilder::AddChunk(CodeCompletionString::ChunkKind CK,
461                                      const char *Text) {
462   Chunks.push_back(Chunk(CK, Text));
463 }
464 
465 void CodeCompletionBuilder::addParentContext(const DeclContext *DC) {
466   if (DC->isTranslationUnit())
467     return;
468 
469   if (DC->isFunctionOrMethod())
470     return;
471 
472   if (!isa<NamedDecl>(DC))
473     return;
474 
475   ParentName = getCodeCompletionTUInfo().getParentName(DC);
476 }
477 
478 void CodeCompletionBuilder::addBriefComment(StringRef Comment) {
479   BriefComment = Allocator.CopyString(Comment);
480 }
481 
482 //===----------------------------------------------------------------------===//
483 // Code completion overload candidate implementation
484 //===----------------------------------------------------------------------===//
485 FunctionDecl *CodeCompleteConsumer::OverloadCandidate::getFunction() const {
486   if (getKind() == CK_Function)
487     return Function;
488   else if (getKind() == CK_FunctionTemplate)
489     return FunctionTemplate->getTemplatedDecl();
490   else
491     return nullptr;
492 }
493 
494 const FunctionType *
495 CodeCompleteConsumer::OverloadCandidate::getFunctionType() const {
496   switch (Kind) {
497   case CK_Function:
498     return Function->getType()->getAs<FunctionType>();
499 
500   case CK_FunctionTemplate:
501     return FunctionTemplate->getTemplatedDecl()
502         ->getType()
503         ->getAs<FunctionType>();
504 
505   case CK_FunctionType:
506     return Type;
507   }
508 
509   llvm_unreachable("Invalid CandidateKind!");
510 }
511 
512 //===----------------------------------------------------------------------===//
513 // Code completion consumer implementation
514 //===----------------------------------------------------------------------===//
515 
516 CodeCompleteConsumer::~CodeCompleteConsumer() = default;
517 
518 bool PrintingCodeCompleteConsumer::isResultFilteredOut(
519     StringRef Filter, CodeCompletionResult Result) {
520   switch (Result.Kind) {
521   case CodeCompletionResult::RK_Declaration:
522     return !(Result.Declaration->getIdentifier() &&
523              Result.Declaration->getIdentifier()->getName().startswith(Filter));
524   case CodeCompletionResult::RK_Keyword:
525     return !StringRef(Result.Keyword).startswith(Filter);
526   case CodeCompletionResult::RK_Macro:
527     return !Result.Macro->getName().startswith(Filter);
528   case CodeCompletionResult::RK_Pattern:
529     return !(Result.Pattern->getTypedText() &&
530              StringRef(Result.Pattern->getTypedText()).startswith(Filter));
531   }
532   llvm_unreachable("Unknown code completion result Kind.");
533 }
534 
535 void PrintingCodeCompleteConsumer::ProcessCodeCompleteResults(
536     Sema &SemaRef, CodeCompletionContext Context, CodeCompletionResult *Results,
537     unsigned NumResults) {
538   std::stable_sort(Results, Results + NumResults);
539 
540   if (!Context.getPreferredType().isNull())
541     OS << "PREFERRED-TYPE: " << Context.getPreferredType().getAsString()
542        << "\n";
543 
544   StringRef Filter = SemaRef.getPreprocessor().getCodeCompletionFilter();
545   // Print the completions.
546   for (unsigned I = 0; I != NumResults; ++I) {
547     if (!Filter.empty() && isResultFilteredOut(Filter, Results[I]))
548       continue;
549     OS << "COMPLETION: ";
550     switch (Results[I].Kind) {
551     case CodeCompletionResult::RK_Declaration:
552       OS << *Results[I].Declaration;
553       {
554         std::vector<std::string> Tags;
555         if (Results[I].Hidden)
556           Tags.push_back("Hidden");
557         if (Results[I].InBaseClass)
558           Tags.push_back("InBase");
559         if (Results[I].Availability ==
560             CXAvailabilityKind::CXAvailability_NotAccessible)
561           Tags.push_back("Inaccessible");
562         if (!Tags.empty())
563           OS << " (" << llvm::join(Tags, ",") << ")";
564       }
565       if (CodeCompletionString *CCS = Results[I].CreateCodeCompletionString(
566               SemaRef, Context, getAllocator(), CCTUInfo,
567               includeBriefComments())) {
568         OS << " : " << CCS->getAsString();
569         if (const char *BriefComment = CCS->getBriefComment())
570           OS << " : " << BriefComment;
571       }
572       break;
573 
574     case CodeCompletionResult::RK_Keyword:
575       OS << Results[I].Keyword;
576       break;
577 
578     case CodeCompletionResult::RK_Macro:
579       OS << Results[I].Macro->getName();
580       if (CodeCompletionString *CCS = Results[I].CreateCodeCompletionString(
581               SemaRef, Context, getAllocator(), CCTUInfo,
582               includeBriefComments())) {
583         OS << " : " << CCS->getAsString();
584       }
585       break;
586 
587     case CodeCompletionResult::RK_Pattern:
588       OS << "Pattern : " << Results[I].Pattern->getAsString();
589       break;
590     }
591     for (const FixItHint &FixIt : Results[I].FixIts) {
592       const SourceLocation BLoc = FixIt.RemoveRange.getBegin();
593       const SourceLocation ELoc = FixIt.RemoveRange.getEnd();
594 
595       SourceManager &SM = SemaRef.SourceMgr;
596       std::pair<FileID, unsigned> BInfo = SM.getDecomposedLoc(BLoc);
597       std::pair<FileID, unsigned> EInfo = SM.getDecomposedLoc(ELoc);
598       // Adjust for token ranges.
599       if (FixIt.RemoveRange.isTokenRange())
600         EInfo.second += Lexer::MeasureTokenLength(ELoc, SM, SemaRef.LangOpts);
601 
602       OS << " (requires fix-it:"
603          << " {" << SM.getLineNumber(BInfo.first, BInfo.second) << ':'
604          << SM.getColumnNumber(BInfo.first, BInfo.second) << '-'
605          << SM.getLineNumber(EInfo.first, EInfo.second) << ':'
606          << SM.getColumnNumber(EInfo.first, EInfo.second) << "}"
607          << " to \"" << FixIt.CodeToInsert << "\")";
608     }
609     OS << '\n';
610   }
611 }
612 
613 // This function is used solely to preserve the former presentation of overloads
614 // by "clang -cc1 -code-completion-at", since CodeCompletionString::getAsString
615 // needs to be improved for printing the newer and more detailed overload
616 // chunks.
617 static std::string getOverloadAsString(const CodeCompletionString &CCS) {
618   std::string Result;
619   llvm::raw_string_ostream OS(Result);
620 
621   for (auto &C : CCS) {
622     switch (C.Kind) {
623     case CodeCompletionString::CK_Informative:
624     case CodeCompletionString::CK_ResultType:
625       OS << "[#" << C.Text << "#]";
626       break;
627 
628     case CodeCompletionString::CK_CurrentParameter:
629       OS << "<#" << C.Text << "#>";
630       break;
631 
632     // FIXME: We can also print optional parameters of an overload.
633     case CodeCompletionString::CK_Optional:
634       break;
635 
636     default:
637       OS << C.Text;
638       break;
639     }
640   }
641   return OS.str();
642 }
643 
644 void PrintingCodeCompleteConsumer::ProcessOverloadCandidates(
645     Sema &SemaRef, unsigned CurrentArg, OverloadCandidate *Candidates,
646     unsigned NumCandidates, SourceLocation OpenParLoc) {
647   OS << "OPENING_PAREN_LOC: ";
648   OpenParLoc.print(OS, SemaRef.getSourceManager());
649   OS << "\n";
650 
651   for (unsigned I = 0; I != NumCandidates; ++I) {
652     if (CodeCompletionString *CCS = Candidates[I].CreateSignatureString(
653             CurrentArg, SemaRef, getAllocator(), CCTUInfo,
654             includeBriefComments())) {
655       OS << "OVERLOAD: " << getOverloadAsString(*CCS) << "\n";
656     }
657   }
658 }
659 
660 /// Retrieve the effective availability of the given declaration.
661 static AvailabilityResult getDeclAvailability(const Decl *D) {
662   AvailabilityResult AR = D->getAvailability();
663   if (isa<EnumConstantDecl>(D))
664     AR = std::max(AR, cast<Decl>(D->getDeclContext())->getAvailability());
665   return AR;
666 }
667 
668 void CodeCompletionResult::computeCursorKindAndAvailability(bool Accessible) {
669   switch (Kind) {
670   case RK_Pattern:
671     if (!Declaration) {
672       // Do nothing: Patterns can come with cursor kinds!
673       break;
674     }
675     LLVM_FALLTHROUGH;
676 
677   case RK_Declaration: {
678     // Set the availability based on attributes.
679     switch (getDeclAvailability(Declaration)) {
680     case AR_Available:
681     case AR_NotYetIntroduced:
682       Availability = CXAvailability_Available;
683       break;
684 
685     case AR_Deprecated:
686       Availability = CXAvailability_Deprecated;
687       break;
688 
689     case AR_Unavailable:
690       Availability = CXAvailability_NotAvailable;
691       break;
692     }
693 
694     if (const auto *Function = dyn_cast<FunctionDecl>(Declaration))
695       if (Function->isDeleted())
696         Availability = CXAvailability_NotAvailable;
697 
698     CursorKind = getCursorKindForDecl(Declaration);
699     if (CursorKind == CXCursor_UnexposedDecl) {
700       // FIXME: Forward declarations of Objective-C classes and protocols
701       // are not directly exposed, but we want code completion to treat them
702       // like a definition.
703       if (isa<ObjCInterfaceDecl>(Declaration))
704         CursorKind = CXCursor_ObjCInterfaceDecl;
705       else if (isa<ObjCProtocolDecl>(Declaration))
706         CursorKind = CXCursor_ObjCProtocolDecl;
707       else
708         CursorKind = CXCursor_NotImplemented;
709     }
710     break;
711   }
712 
713   case RK_Macro:
714   case RK_Keyword:
715     llvm_unreachable("Macro and keyword kinds are handled by the constructors");
716   }
717 
718   if (!Accessible)
719     Availability = CXAvailability_NotAccessible;
720 }
721 
722 /// Retrieve the name that should be used to order a result.
723 ///
724 /// If the name needs to be constructed as a string, that string will be
725 /// saved into Saved and the returned StringRef will refer to it.
726 StringRef CodeCompletionResult::getOrderedName(std::string &Saved) const {
727   switch (Kind) {
728   case RK_Keyword:
729     return Keyword;
730   case RK_Pattern:
731     return Pattern->getTypedText();
732   case RK_Macro:
733     return Macro->getName();
734   case RK_Declaration:
735     // Handle declarations below.
736     break;
737   }
738 
739   DeclarationName Name = Declaration->getDeclName();
740 
741   // If the name is a simple identifier (by far the common case), or a
742   // zero-argument selector, just return a reference to that identifier.
743   if (IdentifierInfo *Id = Name.getAsIdentifierInfo())
744     return Id->getName();
745   if (Name.isObjCZeroArgSelector())
746     if (IdentifierInfo *Id = Name.getObjCSelector().getIdentifierInfoForSlot(0))
747       return Id->getName();
748 
749   Saved = Name.getAsString();
750   return Saved;
751 }
752 
753 bool clang::operator<(const CodeCompletionResult &X,
754                       const CodeCompletionResult &Y) {
755   std::string XSaved, YSaved;
756   StringRef XStr = X.getOrderedName(XSaved);
757   StringRef YStr = Y.getOrderedName(YSaved);
758   int cmp = XStr.compare_lower(YStr);
759   if (cmp)
760     return cmp < 0;
761 
762   // If case-insensitive comparison fails, try case-sensitive comparison.
763   return XStr.compare(YStr) < 0;
764 }
765