1 //===--- CodeCompleteConsumer.cpp - Code Completion Interface ---*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file implements the CodeCompleteConsumer class.
11 //
12 //===----------------------------------------------------------------------===//
13 #include "clang/Sema/CodeCompleteConsumer.h"
14 #include "clang/AST/DeclCXX.h"
15 #include "clang/Parse/Scope.h"
16 #include "clang/Lex/Preprocessor.h"
17 #include "clang-c/Index.h"
18 #include "Sema.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/Support/raw_ostream.h"
21 #include <algorithm>
22 #include <cstring>
23 #include <functional>
24 
25 using namespace clang;
26 using llvm::StringRef;
27 
28 //===----------------------------------------------------------------------===//
29 // Code completion string implementation
30 //===----------------------------------------------------------------------===//
31 CodeCompletionString::Chunk::Chunk(ChunkKind Kind, llvm::StringRef Text)
32   : Kind(Kind), Text("")
33 {
34   switch (Kind) {
35   case CK_TypedText:
36   case CK_Text:
37   case CK_Placeholder:
38   case CK_Informative:
39   case CK_ResultType:
40   case CK_CurrentParameter: {
41     char *New = new char [Text.size() + 1];
42     std::memcpy(New, Text.data(), Text.size());
43     New[Text.size()] = '\0';
44     this->Text = New;
45     break;
46   }
47 
48   case CK_Optional:
49     llvm_unreachable("Optional strings cannot be created from text");
50     break;
51 
52   case CK_LeftParen:
53     this->Text = "(";
54     break;
55 
56   case CK_RightParen:
57     this->Text = ")";
58     break;
59 
60   case CK_LeftBracket:
61     this->Text = "[";
62     break;
63 
64   case CK_RightBracket:
65     this->Text = "]";
66     break;
67 
68   case CK_LeftBrace:
69     this->Text = "{";
70     break;
71 
72   case CK_RightBrace:
73     this->Text = "}";
74     break;
75 
76   case CK_LeftAngle:
77     this->Text = "<";
78     break;
79 
80   case CK_RightAngle:
81     this->Text = ">";
82     break;
83 
84   case CK_Comma:
85     this->Text = ", ";
86     break;
87 
88   case CK_Colon:
89     this->Text = ":";
90     break;
91 
92   case CK_SemiColon:
93     this->Text = ";";
94     break;
95 
96   case CK_Equal:
97     this->Text = " = ";
98     break;
99 
100   case CK_HorizontalSpace:
101     this->Text = " ";
102     break;
103 
104   case CK_VerticalSpace:
105     this->Text = "\n";
106     break;
107   }
108 }
109 
110 CodeCompletionString::Chunk
111 CodeCompletionString::Chunk::CreateText(StringRef Text) {
112   return Chunk(CK_Text, Text);
113 }
114 
115 CodeCompletionString::Chunk
116 CodeCompletionString::Chunk::CreateOptional(
117                                  std::auto_ptr<CodeCompletionString> Optional) {
118   Chunk Result;
119   Result.Kind = CK_Optional;
120   Result.Optional = Optional.release();
121   return Result;
122 }
123 
124 CodeCompletionString::Chunk
125 CodeCompletionString::Chunk::CreatePlaceholder(StringRef Placeholder) {
126   return Chunk(CK_Placeholder, Placeholder);
127 }
128 
129 CodeCompletionString::Chunk
130 CodeCompletionString::Chunk::CreateInformative(StringRef Informative) {
131   return Chunk(CK_Informative, Informative);
132 }
133 
134 CodeCompletionString::Chunk
135 CodeCompletionString::Chunk::CreateResultType(StringRef ResultType) {
136   return Chunk(CK_ResultType, ResultType);
137 }
138 
139 CodeCompletionString::Chunk
140 CodeCompletionString::Chunk::CreateCurrentParameter(
141                                                 StringRef CurrentParameter) {
142   return Chunk(CK_CurrentParameter, CurrentParameter);
143 }
144 
145 CodeCompletionString::Chunk CodeCompletionString::Chunk::Clone() const {
146   switch (Kind) {
147   case CK_TypedText:
148   case CK_Text:
149   case CK_Placeholder:
150   case CK_Informative:
151   case CK_ResultType:
152   case CK_CurrentParameter:
153   case CK_LeftParen:
154   case CK_RightParen:
155   case CK_LeftBracket:
156   case CK_RightBracket:
157   case CK_LeftBrace:
158   case CK_RightBrace:
159   case CK_LeftAngle:
160   case CK_RightAngle:
161   case CK_Comma:
162   case CK_Colon:
163   case CK_SemiColon:
164   case CK_Equal:
165   case CK_HorizontalSpace:
166   case CK_VerticalSpace:
167     return Chunk(Kind, Text);
168 
169   case CK_Optional: {
170     std::auto_ptr<CodeCompletionString> Opt(Optional->Clone());
171     return CreateOptional(Opt);
172   }
173   }
174 
175   // Silence GCC warning.
176   return Chunk();
177 }
178 
179 void
180 CodeCompletionString::Chunk::Destroy() {
181   switch (Kind) {
182   case CK_Optional:
183     delete Optional;
184     break;
185 
186   case CK_TypedText:
187   case CK_Text:
188   case CK_Placeholder:
189   case CK_Informative:
190   case CK_ResultType:
191   case CK_CurrentParameter:
192     delete [] Text;
193     break;
194 
195   case CK_LeftParen:
196   case CK_RightParen:
197   case CK_LeftBracket:
198   case CK_RightBracket:
199   case CK_LeftBrace:
200   case CK_RightBrace:
201   case CK_LeftAngle:
202   case CK_RightAngle:
203   case CK_Comma:
204   case CK_Colon:
205   case CK_SemiColon:
206   case CK_Equal:
207   case CK_HorizontalSpace:
208   case CK_VerticalSpace:
209     break;
210   }
211 }
212 
213 void CodeCompletionString::clear() {
214   std::for_each(Chunks.begin(), Chunks.end(),
215                 std::mem_fun_ref(&Chunk::Destroy));
216   Chunks.clear();
217 }
218 
219 std::string CodeCompletionString::getAsString() const {
220   std::string Result;
221   llvm::raw_string_ostream OS(Result);
222 
223   for (iterator C = begin(), CEnd = end(); C != CEnd; ++C) {
224     switch (C->Kind) {
225     case CK_Optional: OS << "{#" << C->Optional->getAsString() << "#}"; break;
226     case CK_Placeholder: OS << "<#" << C->Text << "#>"; break;
227 
228     case CK_Informative:
229     case CK_ResultType:
230       OS << "[#" << C->Text << "#]";
231       break;
232 
233     case CK_CurrentParameter: OS << "<#" << C->Text << "#>"; break;
234     default: OS << C->Text; break;
235     }
236   }
237   OS.flush();
238   return Result;
239 }
240 
241 const char *CodeCompletionString::getTypedText() const {
242   for (iterator C = begin(), CEnd = end(); C != CEnd; ++C)
243     if (C->Kind == CK_TypedText)
244       return C->Text;
245 
246   return 0;
247 }
248 
249 CodeCompletionString *CodeCompletionString::Clone() const {
250   CodeCompletionString *Result = new CodeCompletionString;
251   for (iterator C = begin(), CEnd = end(); C != CEnd; ++C)
252     Result->AddChunk(C->Clone());
253   return Result;
254 }
255 
256 static void WriteUnsigned(llvm::raw_ostream &OS, unsigned Value) {
257   OS.write((const char *)&Value, sizeof(unsigned));
258 }
259 
260 static bool ReadUnsigned(const char *&Memory, const char *MemoryEnd,
261                          unsigned &Value) {
262   if (Memory + sizeof(unsigned) > MemoryEnd)
263     return true;
264 
265   memmove(&Value, Memory, sizeof(unsigned));
266   Memory += sizeof(unsigned);
267   return false;
268 }
269 
270 void CodeCompletionString::Serialize(llvm::raw_ostream &OS) const {
271   // Write the number of chunks.
272   WriteUnsigned(OS, size());
273 
274   for (iterator C = begin(), CEnd = end(); C != CEnd; ++C) {
275     WriteUnsigned(OS, C->Kind);
276 
277     switch (C->Kind) {
278     case CK_TypedText:
279     case CK_Text:
280     case CK_Placeholder:
281     case CK_Informative:
282     case CK_ResultType:
283     case CK_CurrentParameter: {
284       const char *Text = C->Text;
285       unsigned StrLen = strlen(Text);
286       WriteUnsigned(OS, StrLen);
287       OS.write(Text, StrLen);
288       break;
289     }
290 
291     case CK_Optional:
292       C->Optional->Serialize(OS);
293       break;
294 
295     case CK_LeftParen:
296     case CK_RightParen:
297     case CK_LeftBracket:
298     case CK_RightBracket:
299     case CK_LeftBrace:
300     case CK_RightBrace:
301     case CK_LeftAngle:
302     case CK_RightAngle:
303     case CK_Comma:
304     case CK_Colon:
305     case CK_SemiColon:
306     case CK_Equal:
307     case CK_HorizontalSpace:
308     case CK_VerticalSpace:
309       break;
310     }
311   }
312 }
313 
314 bool CodeCompletionString::Deserialize(const char *&Str, const char *StrEnd) {
315   if (Str == StrEnd || *Str == 0)
316     return false;
317 
318   unsigned NumBlocks;
319   if (ReadUnsigned(Str, StrEnd, NumBlocks))
320     return false;
321 
322   for (unsigned I = 0; I != NumBlocks; ++I) {
323     if (Str + 1 >= StrEnd)
324       break;
325 
326     // Parse the next kind.
327     unsigned KindValue;
328     if (ReadUnsigned(Str, StrEnd, KindValue))
329       return false;
330 
331     switch (ChunkKind Kind = (ChunkKind)KindValue) {
332     case CK_TypedText:
333     case CK_Text:
334     case CK_Placeholder:
335     case CK_Informative:
336     case CK_ResultType:
337     case CK_CurrentParameter: {
338       unsigned StrLen;
339       if (ReadUnsigned(Str, StrEnd, StrLen) || (Str + StrLen > StrEnd))
340         return false;
341 
342       AddChunk(Chunk(Kind, StringRef(Str, StrLen)));
343       Str += StrLen;
344       break;
345     }
346 
347     case CK_Optional: {
348       std::auto_ptr<CodeCompletionString> Optional(new CodeCompletionString());
349       if (Optional->Deserialize(Str, StrEnd))
350         AddOptionalChunk(Optional);
351       break;
352     }
353 
354     case CK_LeftParen:
355     case CK_RightParen:
356     case CK_LeftBracket:
357     case CK_RightBracket:
358     case CK_LeftBrace:
359     case CK_RightBrace:
360     case CK_LeftAngle:
361     case CK_RightAngle:
362     case CK_Comma:
363     case CK_Colon:
364     case CK_SemiColon:
365     case CK_Equal:
366     case CK_HorizontalSpace:
367     case CK_VerticalSpace:
368       AddChunk(Chunk(Kind));
369       break;
370     }
371   };
372 
373   return true;
374 }
375 
376 void CodeCompleteConsumer::Result::Destroy() {
377   if (Kind == RK_Pattern) {
378     delete Pattern;
379     Pattern = 0;
380   }
381 }
382 
383 unsigned CodeCompleteConsumer::Result::getPriorityFromDecl(NamedDecl *ND) {
384   if (!ND)
385     return CCP_Unlikely;
386 
387   // Context-based decisions.
388   DeclContext *DC = ND->getDeclContext()->getLookupContext();
389   if (DC->isFunctionOrMethod() || isa<BlockDecl>(DC))
390     return CCP_LocalDeclaration;
391   if (DC->isRecord() || isa<ObjCContainerDecl>(DC))
392     return CCP_MemberDeclaration;
393 
394   // Content-based decisions.
395   if (isa<EnumConstantDecl>(ND))
396     return CCP_Constant;
397   if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND))
398     return CCP_Type;
399   return CCP_Declaration;
400 }
401 
402 //===----------------------------------------------------------------------===//
403 // Code completion overload candidate implementation
404 //===----------------------------------------------------------------------===//
405 FunctionDecl *
406 CodeCompleteConsumer::OverloadCandidate::getFunction() const {
407   if (getKind() == CK_Function)
408     return Function;
409   else if (getKind() == CK_FunctionTemplate)
410     return FunctionTemplate->getTemplatedDecl();
411   else
412     return 0;
413 }
414 
415 const FunctionType *
416 CodeCompleteConsumer::OverloadCandidate::getFunctionType() const {
417   switch (Kind) {
418   case CK_Function:
419     return Function->getType()->getAs<FunctionType>();
420 
421   case CK_FunctionTemplate:
422     return FunctionTemplate->getTemplatedDecl()->getType()
423              ->getAs<FunctionType>();
424 
425   case CK_FunctionType:
426     return Type;
427   }
428 
429   return 0;
430 }
431 
432 //===----------------------------------------------------------------------===//
433 // Code completion consumer implementation
434 //===----------------------------------------------------------------------===//
435 
436 CodeCompleteConsumer::~CodeCompleteConsumer() { }
437 
438 void
439 PrintingCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &SemaRef,
440                                                          Result *Results,
441                                                          unsigned NumResults) {
442   // Print the results.
443   for (unsigned I = 0; I != NumResults; ++I) {
444     OS << "COMPLETION: ";
445     switch (Results[I].Kind) {
446     case Result::RK_Declaration:
447       OS << Results[I].Declaration;
448       if (Results[I].Hidden)
449         OS << " (Hidden)";
450       if (CodeCompletionString *CCS
451             = Results[I].CreateCodeCompletionString(SemaRef)) {
452         OS << " : " << CCS->getAsString();
453         delete CCS;
454       }
455 
456       OS << '\n';
457       break;
458 
459     case Result::RK_Keyword:
460       OS << Results[I].Keyword << '\n';
461       break;
462 
463     case Result::RK_Macro: {
464       OS << Results[I].Macro->getName();
465       if (CodeCompletionString *CCS
466             = Results[I].CreateCodeCompletionString(SemaRef)) {
467         OS << " : " << CCS->getAsString();
468         delete CCS;
469       }
470       OS << '\n';
471       break;
472     }
473 
474     case Result::RK_Pattern: {
475       OS << "Pattern : "
476          << Results[I].Pattern->getAsString() << '\n';
477       break;
478     }
479     }
480   }
481 }
482 
483 void
484 PrintingCodeCompleteConsumer::ProcessOverloadCandidates(Sema &SemaRef,
485                                                         unsigned CurrentArg,
486                                               OverloadCandidate *Candidates,
487                                                      unsigned NumCandidates) {
488   for (unsigned I = 0; I != NumCandidates; ++I) {
489     if (CodeCompletionString *CCS
490           = Candidates[I].CreateSignatureString(CurrentArg, SemaRef)) {
491       OS << "OVERLOAD: " << CCS->getAsString() << "\n";
492       delete CCS;
493     }
494   }
495 }
496 
497 void
498 CIndexCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &SemaRef,
499                                                        Result *Results,
500                                                        unsigned NumResults) {
501   // Print the results.
502   for (unsigned I = 0; I != NumResults; ++I) {
503     CXCursorKind Kind = CXCursor_NotImplemented;
504 
505     switch (Results[I].Kind) {
506     case Result::RK_Declaration:
507       switch (Results[I].Declaration->getKind()) {
508       case Decl::Record:
509       case Decl::CXXRecord:
510       case Decl::ClassTemplateSpecialization: {
511         RecordDecl *Record = cast<RecordDecl>(Results[I].Declaration);
512         if (Record->isStruct())
513           Kind = CXCursor_StructDecl;
514         else if (Record->isUnion())
515           Kind = CXCursor_UnionDecl;
516         else
517           Kind = CXCursor_ClassDecl;
518         break;
519       }
520 
521       case Decl::ObjCMethod: {
522         ObjCMethodDecl *Method = cast<ObjCMethodDecl>(Results[I].Declaration);
523         if (Method->isInstanceMethod())
524             Kind = CXCursor_ObjCInstanceMethodDecl;
525         else
526           Kind = CXCursor_ObjCClassMethodDecl;
527         break;
528       }
529 
530       case Decl::Typedef:
531         Kind = CXCursor_TypedefDecl;
532         break;
533 
534       case Decl::Enum:
535         Kind = CXCursor_EnumDecl;
536         break;
537 
538       case Decl::Field:
539         Kind = CXCursor_FieldDecl;
540         break;
541 
542       case Decl::EnumConstant:
543         Kind = CXCursor_EnumConstantDecl;
544         break;
545 
546       case Decl::Function:
547       case Decl::CXXMethod:
548       case Decl::CXXConstructor:
549       case Decl::CXXDestructor:
550       case Decl::CXXConversion:
551         Kind = CXCursor_FunctionDecl;
552         break;
553 
554       case Decl::Var:
555         Kind = CXCursor_VarDecl;
556         break;
557 
558       case Decl::ParmVar:
559         Kind = CXCursor_ParmDecl;
560         break;
561 
562       case Decl::ObjCInterface:
563         Kind = CXCursor_ObjCInterfaceDecl;
564         break;
565 
566       case Decl::ObjCCategory:
567         Kind = CXCursor_ObjCCategoryDecl;
568         break;
569 
570       case Decl::ObjCProtocol:
571         Kind = CXCursor_ObjCProtocolDecl;
572         break;
573 
574       case Decl::ObjCProperty:
575         Kind = CXCursor_ObjCPropertyDecl;
576         break;
577 
578       case Decl::ObjCIvar:
579         Kind = CXCursor_ObjCIvarDecl;
580         break;
581 
582       case Decl::ObjCImplementation:
583         Kind = CXCursor_ObjCImplementationDecl;
584         break;
585 
586       case Decl::ObjCCategoryImpl:
587         Kind = CXCursor_ObjCCategoryImplDecl;
588         break;
589 
590       default:
591         break;
592       }
593       break;
594 
595     case Result::RK_Macro:
596       Kind = CXCursor_MacroDefinition;
597       break;
598 
599     case Result::RK_Keyword:
600     case Result::RK_Pattern:
601       Kind = CXCursor_NotImplemented;
602       break;
603     }
604 
605     WriteUnsigned(OS, Kind);
606     WriteUnsigned(OS, Results[I].Priority);
607     CodeCompletionString *CCS = Results[I].CreateCodeCompletionString(SemaRef);
608     assert(CCS && "No code-completion string?");
609     CCS->Serialize(OS);
610     delete CCS;
611   }
612 }
613 
614 void
615 CIndexCodeCompleteConsumer::ProcessOverloadCandidates(Sema &SemaRef,
616                                                       unsigned CurrentArg,
617                                                 OverloadCandidate *Candidates,
618                                                        unsigned NumCandidates) {
619   for (unsigned I = 0; I != NumCandidates; ++I) {
620     WriteUnsigned(OS, CXCursor_NotImplemented);
621     WriteUnsigned(OS, /*Priority=*/0);
622     CodeCompletionString *CCS
623       = Candidates[I].CreateSignatureString(CurrentArg, SemaRef);
624     assert(CCS && "No code-completion string?");
625     CCS->Serialize(OS);
626     delete CCS;
627   }
628 }
629