clang/lib/Sema/CodeCompleteConsumer.cpp

   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   case CCC_Attribute:
  86   case CCC_ObjCClassForwardDecl:
  87     return false;
  88   }
  89
  90   llvm_unreachable("Invalid CodeCompletionContext::Kind!");
  91 }
  92
  93 StringRef clang::getCompletionKindString(CodeCompletionContext::Kind Kind) {
  94   using CCKind = CodeCompletionContext::Kind;
  95   switch (Kind) {
  96   case CCKind::CCC_Other:
  97     return "Other";
  98   case CCKind::CCC_OtherWithMacros:
  99     return "OtherWithMacros";
 100   case CCKind::CCC_TopLevel:
 101     return "TopLevel";
 102   case CCKind::CCC_ObjCInterface:
 103     return "ObjCInterface";
 104   case CCKind::CCC_ObjCImplementation:
 105     return "ObjCImplementation";
 106   case CCKind::CCC_ObjCIvarList:
 107     return "ObjCIvarList";
 108   case CCKind::CCC_ClassStructUnion:
 109     return "ClassStructUnion";
 110   case CCKind::CCC_Statement:
 111     return "Statement";
 112   case CCKind::CCC_Expression:
 113     return "Expression";
 114   case CCKind::CCC_ObjCMessageReceiver:
 115     return "ObjCMessageReceiver";
 116   case CCKind::CCC_DotMemberAccess:
 117     return "DotMemberAccess";
 118   case CCKind::CCC_ArrowMemberAccess:
 119     return "ArrowMemberAccess";
 120   case CCKind::CCC_ObjCPropertyAccess:
 121     return "ObjCPropertyAccess";
 122   case CCKind::CCC_EnumTag:
 123     return "EnumTag";
 124   case CCKind::CCC_UnionTag:
 125     return "UnionTag";
 126   case CCKind::CCC_ClassOrStructTag:
 127     return "ClassOrStructTag";
 128   case CCKind::CCC_ObjCProtocolName:
 129     return "ObjCProtocolName";
 130   case CCKind::CCC_Namespace:
 131     return "Namespace";
 132   case CCKind::CCC_Type:
 133     return "Type";
 134   case CCKind::CCC_NewName:
 135     return "NewName";
 136   case CCKind::CCC_Symbol:
 137     return "Symbol";
 138   case CCKind::CCC_SymbolOrNewName:
 139     return "SymbolOrNewName";
 140   case CCKind::CCC_MacroName:
 141     return "MacroName";
 142   case CCKind::CCC_MacroNameUse:
 143     return "MacroNameUse";
 144   case CCKind::CCC_PreprocessorExpression:
 145     return "PreprocessorExpression";
 146   case CCKind::CCC_PreprocessorDirective:
 147     return "PreprocessorDirective";
 148   case CCKind::CCC_NaturalLanguage:
 149     return "NaturalLanguage";
 150   case CCKind::CCC_SelectorName:
 151     return "SelectorName";
 152   case CCKind::CCC_TypeQualifiers:
 153     return "TypeQualifiers";
 154   case CCKind::CCC_ParenthesizedExpression:
 155     return "ParenthesizedExpression";
 156   case CCKind::CCC_ObjCInstanceMessage:
 157     return "ObjCInstanceMessage";
 158   case CCKind::CCC_ObjCClassMessage:
 159     return "ObjCClassMessage";
 160   case CCKind::CCC_ObjCInterfaceName:
 161     return "ObjCInterfaceName";
 162   case CCKind::CCC_ObjCCategoryName:
 163     return "ObjCCategoryName";
 164   case CCKind::CCC_IncludedFile:
 165     return "IncludedFile";
 166   case CCKind::CCC_Attribute:
 167     return "Attribute";
 168   case CCKind::CCC_Recovery:
 169     return "Recovery";
 170   case CCKind::CCC_ObjCClassForwardDecl:
 171     return "ObjCClassForwardDecl";
 172   }
 173   llvm_unreachable("Invalid CodeCompletionContext::Kind!");
 174 }
 175
 176 //===----------------------------------------------------------------------===//
 177 // Code completion string implementation
 178 //===----------------------------------------------------------------------===//
 179
 180 CodeCompletionString::Chunk::Chunk(ChunkKind Kind, const char *Text)
 181     : Kind(Kind), Text("") {
 182   switch (Kind) {
 183   case CK_TypedText:
 184   case CK_Text:
 185   case CK_Placeholder:
 186   case CK_Informative:
 187   case CK_ResultType:
 188   case CK_CurrentParameter:
 189     this->Text = Text;
 190     break;
 191
 192   case CK_Optional:
 193     llvm_unreachable("Optional strings cannot be created from text");
 194
 195   case CK_LeftParen:
 196     this->Text = "(";
 197     break;
 198
 199   case CK_RightParen:
 200     this->Text = ")";
 201     break;
 202
 203   case CK_LeftBracket:
 204     this->Text = "[";
 205     break;
 206
 207   case CK_RightBracket:
 208     this->Text = "]";
 209     break;
 210
 211   case CK_LeftBrace:
 212     this->Text = "{";
 213     break;
 214
 215   case CK_RightBrace:
 216     this->Text = "}";
 217     break;
 218
 219   case CK_LeftAngle:
 220     this->Text = "<";
 221     break;
 222
 223   case CK_RightAngle:
 224     this->Text = ">";
 225     break;
 226
 227   case CK_Comma:
 228     this->Text = ", ";
 229     break;
 230
 231   case CK_Colon:
 232     this->Text = ":";
 233     break;
 234
 235   case CK_SemiColon:
 236     this->Text = ";";
 237     break;
 238
 239   case CK_Equal:
 240     this->Text = " = ";
 241     break;
 242
 243   case CK_HorizontalSpace:
 244     this->Text = " ";
 245     break;
 246
 247   case CK_VerticalSpace:
 248     this->Text = "\n";
 249     break;
 250   }
 251 }
 252
 253 CodeCompletionString::Chunk
 254 CodeCompletionString::Chunk::CreateText(const char *Text) {
 255   return Chunk(CK_Text, Text);
 256 }
 257
 258 CodeCompletionString::Chunk
 259 CodeCompletionString::Chunk::CreateOptional(CodeCompletionString *Optional) {
 260   Chunk Result;
 261   Result.Kind = CK_Optional;
 262   Result.Optional = Optional;
 263   return Result;
 264 }
 265
 266 CodeCompletionString::Chunk
 267 CodeCompletionString::Chunk::CreatePlaceholder(const char *Placeholder) {
 268   return Chunk(CK_Placeholder, Placeholder);
 269 }
 270
 271 CodeCompletionString::Chunk
 272 CodeCompletionString::Chunk::CreateInformative(const char *Informative) {
 273   return Chunk(CK_Informative, Informative);
 274 }
 275
 276 CodeCompletionString::Chunk
 277 CodeCompletionString::Chunk::CreateResultType(const char *ResultType) {
 278   return Chunk(CK_ResultType, ResultType);
 279 }
 280
 281 CodeCompletionString::Chunk CodeCompletionString::Chunk::CreateCurrentParameter(
 282     const char *CurrentParameter) {
 283   return Chunk(CK_CurrentParameter, CurrentParameter);
 284 }
 285
 286 CodeCompletionString::CodeCompletionString(
 287     const Chunk *Chunks, unsigned NumChunks, unsigned Priority,
 288     CXAvailabilityKind Availability, const char **Annotations,
 289     unsigned NumAnnotations, StringRef ParentName, const char *BriefComment)
 290     : NumChunks(NumChunks), NumAnnotations(NumAnnotations), Priority(Priority),
 291       Availability(Availability), ParentName(ParentName),
 292       BriefComment(BriefComment) {
 293   assert(NumChunks <= 0xffff);
 294   assert(NumAnnotations <= 0xffff);
 295
 296   Chunk *StoredChunks = reinterpret_cast<Chunk *>(this + 1);
 297   for (unsigned I = 0; I != NumChunks; ++I)
 298     StoredChunks[I] = Chunks[I];
 299
 300   const char **StoredAnnotations =
 301       reinterpret_cast<const char **>(StoredChunks + NumChunks);
 302   for (unsigned I = 0; I != NumAnnotations; ++I)
 303     StoredAnnotations[I] = Annotations[I];
 304 }
 305
 306 unsigned CodeCompletionString::getAnnotationCount() const {
 307   return NumAnnotations;
 308 }
 309
 310 const char *CodeCompletionString::getAnnotation(unsigned AnnotationNr) const {
 311   if (AnnotationNr < NumAnnotations)
 312     return reinterpret_cast<const char *const *>(end())[AnnotationNr];
 313   else
 314     return nullptr;
 315 }
 316
 317 std::string CodeCompletionString::getAsString() const {
 318   std::string Result;
 319   llvm::raw_string_ostream OS(Result);
 320
 321   for (const Chunk &C : *this) {
 322     switch (C.Kind) {
 323     case CK_Optional:
 324       OS << "{#" << C.Optional->getAsString() << "#}";
 325       break;
 326     case CK_Placeholder:
 327       OS << "<#" << C.Text << "#>";
 328       break;
 329     case CK_Informative:
 330     case CK_ResultType:
 331       OS << "[#" << C.Text << "#]";
 332       break;
 333     case CK_CurrentParameter:
 334       OS << "<#" << C.Text << "#>";
 335       break;
 336     default:
 337       OS << C.Text;
 338       break;
 339     }
 340   }
 341   return Result;
 342 }
 343
 344 const char *CodeCompletionString::getTypedText() const {
 345   for (const Chunk &C : *this)
 346     if (C.Kind == CK_TypedText)
 347       return C.Text;
 348
 349   return nullptr;
 350 }
 351
 352 std::string CodeCompletionString::getAllTypedText() const {
 353   std::string Res;
 354   for (const Chunk &C : *this)
 355     if (C.Kind == CK_TypedText)
 356       Res += C.Text;
 357
 358   return Res;
 359 }
 360
 361 const char *CodeCompletionAllocator::CopyString(const Twine &String) {
 362   SmallString<128> Data;
 363   StringRef Ref = String.toStringRef(Data);
 364   // FIXME: It would be more efficient to teach Twine to tell us its size and
 365   // then add a routine there to fill in an allocated char* with the contents
 366   // of the string.
 367   char *Mem = (char *)Allocate(Ref.size() + 1, 1);
 368   std::copy(Ref.begin(), Ref.end(), Mem);
 369   Mem[Ref.size()] = 0;
 370   return Mem;
 371 }
 372
 373 StringRef CodeCompletionTUInfo::getParentName(const DeclContext *DC) {
 374   if (!isa<NamedDecl>(DC))
 375     return {};
 376
 377   // Check whether we've already cached the parent name.
 378   StringRef &CachedParentName = ParentNames[DC];
 379   if (!CachedParentName.empty())
 380     return CachedParentName;
 381
 382   // If we already processed this DeclContext and assigned empty to it, the
 383   // data pointer will be non-null.
 384   if (CachedParentName.data() != nullptr)
 385     return {};
 386
 387   // Find the interesting names.
 388   SmallVector<const DeclContext *, 2> Contexts;
 389   while (DC && !DC->isFunctionOrMethod()) {
 390     if (const auto *ND = dyn_cast<NamedDecl>(DC)) {
 391       if (ND->getIdentifier())
 392         Contexts.push_back(DC);
 393     }
 394
 395     DC = DC->getParent();
 396   }
 397
 398   {
 399     SmallString<128> S;
 400     llvm::raw_svector_ostream OS(S);
 401     bool First = true;
 402     for (const DeclContext *CurDC : llvm::reverse(Contexts)) {
 403       if (First)
 404         First = false;
 405       else {
 406         OS << "::";
 407       }
 408
 409       if (const auto *CatImpl = dyn_cast<ObjCCategoryImplDecl>(CurDC))
 410         CurDC = CatImpl->getCategoryDecl();
 411
 412       if (const auto *Cat = dyn_cast<ObjCCategoryDecl>(CurDC)) {
 413         const ObjCInterfaceDecl *Interface = Cat->getClassInterface();
 414         if (!Interface) {
 415           // Assign an empty StringRef but with non-null data to distinguish
 416           // between empty because we didn't process the DeclContext yet.
 417           CachedParentName = StringRef((const char *)(uintptr_t)~0U, 0);
 418           return {};
 419         }
 420
 421         OS << Interface->getName() << '(' << Cat->getName() << ')';
 422       } else {
 423         OS << cast<NamedDecl>(CurDC)->getName();
 424       }
 425     }
 426
 427     CachedParentName = AllocatorRef->CopyString(OS.str());
 428   }
 429
 430   return CachedParentName;
 431 }
 432
 433 CodeCompletionString *CodeCompletionBuilder::TakeString() {
 434   void *Mem = getAllocator().Allocate(
 435       sizeof(CodeCompletionString) + sizeof(Chunk) * Chunks.size() +
 436           sizeof(const char *) * Annotations.size(),
 437       alignof(CodeCompletionString));
 438   CodeCompletionString *Result = new (Mem) CodeCompletionString(
 439       Chunks.data(), Chunks.size(), Priority, Availability, Annotations.data(),
 440       Annotations.size(), ParentName, BriefComment);
 441   Chunks.clear();
 442   return Result;
 443 }
 444
 445 void CodeCompletionBuilder::AddTypedTextChunk(const char *Text) {
 446   Chunks.push_back(Chunk(CodeCompletionString::CK_TypedText, Text));
 447 }
 448
 449 void CodeCompletionBuilder::AddTextChunk(const char *Text) {
 450   Chunks.push_back(Chunk::CreateText(Text));
 451 }
 452
 453 void CodeCompletionBuilder::AddOptionalChunk(CodeCompletionString *Optional) {
 454   Chunks.push_back(Chunk::CreateOptional(Optional));
 455 }
 456
 457 void CodeCompletionBuilder::AddPlaceholderChunk(const char *Placeholder) {
 458   Chunks.push_back(Chunk::CreatePlaceholder(Placeholder));
 459 }
 460
 461 void CodeCompletionBuilder::AddInformativeChunk(const char *Text) {
 462   Chunks.push_back(Chunk::CreateInformative(Text));
 463 }
 464
 465 void CodeCompletionBuilder::AddResultTypeChunk(const char *ResultType) {
 466   Chunks.push_back(Chunk::CreateResultType(ResultType));
 467 }
 468
 469 void CodeCompletionBuilder::AddCurrentParameterChunk(
 470     const char *CurrentParameter) {
 471   Chunks.push_back(Chunk::CreateCurrentParameter(CurrentParameter));
 472 }
 473
 474 void CodeCompletionBuilder::AddChunk(CodeCompletionString::ChunkKind CK,
 475                                      const char *Text) {
 476   Chunks.push_back(Chunk(CK, Text));
 477 }
 478
 479 void CodeCompletionBuilder::addParentContext(const DeclContext *DC) {
 480   if (DC->isTranslationUnit())
 481     return;
 482
 483   if (DC->isFunctionOrMethod())
 484     return;
 485
 486   if (!isa<NamedDecl>(DC))
 487     return;
 488
 489   ParentName = getCodeCompletionTUInfo().getParentName(DC);
 490 }
 491
 492 void CodeCompletionBuilder::addBriefComment(StringRef Comment) {
 493   BriefComment = Allocator.CopyString(Comment);
 494 }
 495
 496 //===----------------------------------------------------------------------===//
 497 // Code completion overload candidate implementation
 498 //===----------------------------------------------------------------------===//
 499 FunctionDecl *CodeCompleteConsumer::OverloadCandidate::getFunction() const {
 500   if (getKind() == CK_Function)
 501     return Function;
 502   else if (getKind() == CK_FunctionTemplate)
 503     return FunctionTemplate->getTemplatedDecl();
 504   else
 505     return nullptr;
 506 }
 507
 508 const FunctionType *
 509 CodeCompleteConsumer::OverloadCandidate::getFunctionType() const {
 510   switch (Kind) {
 511   case CK_Function:
 512     return Function->getType()->getAs<FunctionType>();
 513
 514   case CK_FunctionTemplate:
 515     return FunctionTemplate->getTemplatedDecl()
 516         ->getType()
 517         ->getAs<FunctionType>();
 518
 519   case CK_FunctionType:
 520     return Type;
 521   case CK_FunctionProtoTypeLoc:
 522     return ProtoTypeLoc.getTypePtr();
 523   case CK_Template:
 524   case CK_Aggregate:
 525     return nullptr;
 526   }
 527
 528   llvm_unreachable("Invalid CandidateKind!");
 529 }
 530
 531 const FunctionProtoTypeLoc
 532 CodeCompleteConsumer::OverloadCandidate::getFunctionProtoTypeLoc() const {
 533   if (Kind == CK_FunctionProtoTypeLoc)
 534     return ProtoTypeLoc;
 535   return FunctionProtoTypeLoc();
 536 }
 537
 538 unsigned CodeCompleteConsumer::OverloadCandidate::getNumParams() const {
 539   if (Kind == CK_Template)
 540     return Template->getTemplateParameters()->size();
 541
 542   if (Kind == CK_Aggregate) {
 543     unsigned Count =
 544         std::distance(AggregateType->field_begin(), AggregateType->field_end());
 545     if (const auto *CRD = dyn_cast<CXXRecordDecl>(AggregateType))
 546       Count += CRD->getNumBases();
 547     return Count;
 548   }
 549
 550   if (const auto *FT = getFunctionType())
 551     if (const auto *FPT = dyn_cast<FunctionProtoType>(FT))
 552       return FPT->getNumParams();
 553
 554   return 0;
 555 }
 556
 557 QualType
 558 CodeCompleteConsumer::OverloadCandidate::getParamType(unsigned N) const {
 559   if (Kind == CK_Aggregate) {
 560     if (const auto *CRD = dyn_cast<CXXRecordDecl>(AggregateType)) {
 561       if (N < CRD->getNumBases())
 562         return std::next(CRD->bases_begin(), N)->getType();
 563       N -= CRD->getNumBases();
 564     }
 565     for (const auto *Field : AggregateType->fields())
 566       if (N-- == 0)
 567         return Field->getType();
 568     return QualType();
 569   }
 570
 571   if (Kind == CK_Template) {
 572     TemplateParameterList *TPL = getTemplate()->getTemplateParameters();
 573     if (N < TPL->size())
 574       if (const auto *D = dyn_cast<NonTypeTemplateParmDecl>(TPL->getParam(N)))
 575         return D->getType();
 576     return QualType();
 577   }
 578
 579   if (const auto *FT = getFunctionType())
 580     if (const auto *FPT = dyn_cast<FunctionProtoType>(FT))
 581       if (N < FPT->getNumParams())
 582         return FPT->getParamType(N);
 583   return QualType();
 584 }
 585
 586 const NamedDecl *
 587 CodeCompleteConsumer::OverloadCandidate::getParamDecl(unsigned N) const {
 588   if (Kind == CK_Aggregate) {
 589     if (const auto *CRD = dyn_cast<CXXRecordDecl>(AggregateType)) {
 590       if (N < CRD->getNumBases())
 591         return std::next(CRD->bases_begin(), N)->getType()->getAsTagDecl();
 592       N -= CRD->getNumBases();
 593     }
 594     for (const auto *Field : AggregateType->fields())
 595       if (N-- == 0)
 596         return Field;
 597     return nullptr;
 598   }
 599
 600   if (Kind == CK_Template) {
 601     TemplateParameterList *TPL = getTemplate()->getTemplateParameters();
 602     if (N < TPL->size())
 603       return TPL->getParam(N);
 604     return nullptr;
 605   }
 606
 607   // Note that if we only have a FunctionProtoType, we don't have param decls.
 608   if (const auto *FD = getFunction()) {
 609     if (N < FD->param_size())
 610       return FD->getParamDecl(N);
 611   } else if (Kind == CK_FunctionProtoTypeLoc) {
 612     if (N < ProtoTypeLoc.getNumParams()) {
 613       return ProtoTypeLoc.getParam(N);
 614     }
 615   }
 616
 617   return nullptr;
 618 }
 619
 620 //===----------------------------------------------------------------------===//
 621 // Code completion consumer implementation
 622 //===----------------------------------------------------------------------===//
 623
 624 CodeCompleteConsumer::~CodeCompleteConsumer() = default;
 625
 626 bool PrintingCodeCompleteConsumer::isResultFilteredOut(
 627     StringRef Filter, CodeCompletionResult Result) {
 628   switch (Result.Kind) {
 629   case CodeCompletionResult::RK_Declaration:
 630     return !(Result.Declaration->getIdentifier() &&
 631              Result.Declaration->getIdentifier()->getName().startswith(Filter));
 632   case CodeCompletionResult::RK_Keyword:
 633     return !StringRef(Result.Keyword).startswith(Filter);
 634   case CodeCompletionResult::RK_Macro:
 635     return !Result.Macro->getName().startswith(Filter);
 636   case CodeCompletionResult::RK_Pattern:
 637     return !(Result.Pattern->getTypedText() &&
 638              StringRef(Result.Pattern->getTypedText()).startswith(Filter));
 639   }
 640   llvm_unreachable("Unknown code completion result Kind.");
 641 }
 642
 643 void PrintingCodeCompleteConsumer::ProcessCodeCompleteResults(
 644     Sema &SemaRef, CodeCompletionContext Context, CodeCompletionResult *Results,
 645     unsigned NumResults) {
 646   std::stable_sort(Results, Results + NumResults);
 647
 648   if (!Context.getPreferredType().isNull())
 649     OS << "PREFERRED-TYPE: " << Context.getPreferredType() << '\n';
 650
 651   StringRef Filter = SemaRef.getPreprocessor().getCodeCompletionFilter();
 652   // Print the completions.
 653   for (unsigned I = 0; I != NumResults; ++I) {
 654     if (!Filter.empty() && isResultFilteredOut(Filter, Results[I]))
 655       continue;
 656     OS << "COMPLETION: ";
 657     switch (Results[I].Kind) {
 658     case CodeCompletionResult::RK_Declaration:
 659       OS << *Results[I].Declaration;
 660       {
 661         std::vector<std::string> Tags;
 662         if (Results[I].Hidden)
 663           Tags.push_back("Hidden");
 664         if (Results[I].InBaseClass)
 665           Tags.push_back("InBase");
 666         if (Results[I].Availability ==
 667             CXAvailabilityKind::CXAvailability_NotAccessible)
 668           Tags.push_back("Inaccessible");
 669         if (!Tags.empty())
 670           OS << " (" << llvm::join(Tags, ",") << ")";
 671       }
 672       if (CodeCompletionString *CCS = Results[I].CreateCodeCompletionString(
 673               SemaRef, Context, getAllocator(), CCTUInfo,
 674               includeBriefComments())) {
 675         OS << " : " << CCS->getAsString();
 676         if (const char *BriefComment = CCS->getBriefComment())
 677           OS << " : " << BriefComment;
 678       }
 679       break;
 680
 681     case CodeCompletionResult::RK_Keyword:
 682       OS << Results[I].Keyword;
 683       break;
 684
 685     case CodeCompletionResult::RK_Macro:
 686       OS << Results[I].Macro->getName();
 687       if (CodeCompletionString *CCS = Results[I].CreateCodeCompletionString(
 688               SemaRef, Context, getAllocator(), CCTUInfo,
 689               includeBriefComments())) {
 690         OS << " : " << CCS->getAsString();
 691       }
 692       break;
 693
 694     case CodeCompletionResult::RK_Pattern:
 695       OS << "Pattern : " << Results[I].Pattern->getAsString();
 696       break;
 697     }
 698     for (const FixItHint &FixIt : Results[I].FixIts) {
 699       const SourceLocation BLoc = FixIt.RemoveRange.getBegin();
 700       const SourceLocation ELoc = FixIt.RemoveRange.getEnd();
 701
 702       SourceManager &SM = SemaRef.SourceMgr;
 703       std::pair<FileID, unsigned> BInfo = SM.getDecomposedLoc(BLoc);
 704       std::pair<FileID, unsigned> EInfo = SM.getDecomposedLoc(ELoc);
 705       // Adjust for token ranges.
 706       if (FixIt.RemoveRange.isTokenRange())
 707         EInfo.second += Lexer::MeasureTokenLength(ELoc, SM, SemaRef.LangOpts);
 708
 709       OS << " (requires fix-it:"
 710          << " {" << SM.getLineNumber(BInfo.first, BInfo.second) << ':'
 711          << SM.getColumnNumber(BInfo.first, BInfo.second) << '-'
 712          << SM.getLineNumber(EInfo.first, EInfo.second) << ':'
 713          << SM.getColumnNumber(EInfo.first, EInfo.second) << "}"
 714          << " to \"" << FixIt.CodeToInsert << "\")";
 715     }
 716     OS << '\n';
 717   }
 718 }
 719
 720 // This function is used solely to preserve the former presentation of overloads
 721 // by "clang -cc1 -code-completion-at", since CodeCompletionString::getAsString
 722 // needs to be improved for printing the newer and more detailed overload
 723 // chunks.
 724 static std::string getOverloadAsString(const CodeCompletionString &CCS) {
 725   std::string Result;
 726   llvm::raw_string_ostream OS(Result);
 727
 728   for (auto &C : CCS) {
 729     switch (C.Kind) {
 730     case CodeCompletionString::CK_Informative:
 731     case CodeCompletionString::CK_ResultType:
 732       OS << "[#" << C.Text << "#]";
 733       break;
 734
 735     case CodeCompletionString::CK_CurrentParameter:
 736       OS << "<#" << C.Text << "#>";
 737       break;
 738
 739     // FIXME: We can also print optional parameters of an overload.
 740     case CodeCompletionString::CK_Optional:
 741       break;
 742
 743     default:
 744       OS << C.Text;
 745       break;
 746     }
 747   }
 748   return Result;
 749 }
 750
 751 void PrintingCodeCompleteConsumer::ProcessOverloadCandidates(
 752     Sema &SemaRef, unsigned CurrentArg, OverloadCandidate *Candidates,
 753     unsigned NumCandidates, SourceLocation OpenParLoc, bool Braced) {
 754   OS << "OPENING_PAREN_LOC: ";
 755   OpenParLoc.print(OS, SemaRef.getSourceManager());
 756   OS << "\n";
 757
 758   for (unsigned I = 0; I != NumCandidates; ++I) {
 759     if (CodeCompletionString *CCS = Candidates[I].CreateSignatureString(
 760             CurrentArg, SemaRef, getAllocator(), CCTUInfo,
 761             includeBriefComments(), Braced)) {
 762       OS << "OVERLOAD: " << getOverloadAsString(*CCS) << "\n";
 763     }
 764   }
 765 }
 766
 767 /// Retrieve the effective availability of the given declaration.
 768 static AvailabilityResult getDeclAvailability(const Decl *D) {
 769   AvailabilityResult AR = D->getAvailability();
 770   if (isa<EnumConstantDecl>(D))
 771     AR = std::max(AR, cast<Decl>(D->getDeclContext())->getAvailability());
 772   return AR;
 773 }
 774
 775 void CodeCompletionResult::computeCursorKindAndAvailability(bool Accessible) {
 776   switch (Kind) {
 777   case RK_Pattern:
 778     if (!Declaration) {
 779       // Do nothing: Patterns can come with cursor kinds!
 780       break;
 781     }
 782     [[fallthrough]];
 783
 784   case RK_Declaration: {
 785     // Set the availability based on attributes.
 786     switch (getDeclAvailability(Declaration)) {
 787     case AR_Available:
 788     case AR_NotYetIntroduced:
 789       Availability = CXAvailability_Available;
 790       break;
 791
 792     case AR_Deprecated:
 793       Availability = CXAvailability_Deprecated;
 794       break;
 795
 796     case AR_Unavailable:
 797       Availability = CXAvailability_NotAvailable;
 798       break;
 799     }
 800
 801     if (const auto *Function = dyn_cast<FunctionDecl>(Declaration))
 802       if (Function->isDeleted())
 803         Availability = CXAvailability_NotAvailable;
 804
 805     CursorKind = getCursorKindForDecl(Declaration);
 806     if (CursorKind == CXCursor_UnexposedDecl) {
 807       // FIXME: Forward declarations of Objective-C classes and protocols
 808       // are not directly exposed, but we want code completion to treat them
 809       // like a definition.
 810       if (isa<ObjCInterfaceDecl>(Declaration))
 811         CursorKind = CXCursor_ObjCInterfaceDecl;
 812       else if (isa<ObjCProtocolDecl>(Declaration))
 813         CursorKind = CXCursor_ObjCProtocolDecl;
 814       else
 815         CursorKind = CXCursor_NotImplemented;
 816     }
 817     break;
 818   }
 819
 820   case RK_Macro:
 821   case RK_Keyword:
 822     llvm_unreachable("Macro and keyword kinds are handled by the constructors");
 823   }
 824
 825   if (!Accessible)
 826     Availability = CXAvailability_NotAccessible;
 827 }
 828
 829 /// Retrieve the name that should be used to order a result.
 830 ///
 831 /// If the name needs to be constructed as a string, that string will be
 832 /// saved into Saved and the returned StringRef will refer to it.
 833 StringRef CodeCompletionResult::getOrderedName(std::string &Saved) const {
 834   switch (Kind) {
 835   case RK_Keyword:
 836     return Keyword;
 837   case RK_Pattern:
 838     return Pattern->getTypedText();
 839   case RK_Macro:
 840     return Macro->getName();
 841   case RK_Declaration:
 842     // Handle declarations below.
 843     break;
 844   }
 845
 846   DeclarationName Name = Declaration->getDeclName();
 847
 848   // If the name is a simple identifier (by far the common case), or a
 849   // zero-argument selector, just return a reference to that identifier.
 850   if (IdentifierInfo *Id = Name.getAsIdentifierInfo())
 851     return Id->getName();
 852   if (Name.isObjCZeroArgSelector())
 853     if (IdentifierInfo *Id = Name.getObjCSelector().getIdentifierInfoForSlot(0))
 854       return Id->getName();
 855
 856   Saved = Name.getAsString();
 857   return Saved;
 858 }
 859
 860 bool clang::operator<(const CodeCompletionResult &X,
 861                       const CodeCompletionResult &Y) {
 862   std::string XSaved, YSaved;
 863   StringRef XStr = X.getOrderedName(XSaved);
 864   StringRef YStr = Y.getOrderedName(YSaved);
 865   int cmp = XStr.compare_insensitive(YStr);
 866   if (cmp)
 867     return cmp < 0;
 868
 869   // If case-insensitive comparison fails, try case-sensitive comparison.
 870   return XStr.compare(YStr) < 0;
 871 }