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      1 //===---- CodeCompleteConsumer.h - 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 defines the CodeCompleteConsumer class.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 #ifndef LLVM_CLANG_SEMA_CODECOMPLETECONSUMER_H
     14 #define LLVM_CLANG_SEMA_CODECOMPLETECONSUMER_H
     15 
     16 #include "clang/AST/Type.h"
     17 #include "clang/AST/CanonicalType.h"
     18 #include "clang/Sema/CodeCompleteOptions.h"
     19 #include "llvm/ADT/SmallVector.h"
     20 #include "llvm/ADT/StringRef.h"
     21 #include "llvm/Support/Allocator.h"
     22 #include "clang-c/Index.h"
     23 #include <string>
     24 
     25 namespace clang {
     26 
     27 class Decl;
     28 
     29 /// \brief Default priority values for code-completion results based
     30 /// on their kind.
     31 enum {
     32   /// \brief Priority for the next initialization in a constructor initializer
     33   /// list.
     34   CCP_NextInitializer = 7,
     35   /// \brief Priority for an enumeration constant inside a switch whose
     36   /// condition is of the enumeration type.
     37   CCP_EnumInCase = 7,
     38   /// \brief Priority for a send-to-super completion.
     39   CCP_SuperCompletion = 20,
     40   /// \brief Priority for a declaration that is in the local scope.
     41   CCP_LocalDeclaration = 34,
     42   /// \brief Priority for a member declaration found from the current
     43   /// method or member function.
     44   CCP_MemberDeclaration = 35,
     45   /// \brief Priority for a language keyword (that isn't any of the other
     46   /// categories).
     47   CCP_Keyword = 40,
     48   /// \brief Priority for a code pattern.
     49   CCP_CodePattern = 40,
     50   /// \brief Priority for a non-type declaration.
     51   CCP_Declaration = 50,
     52   /// \brief Priority for a type.
     53   CCP_Type = CCP_Declaration,
     54   /// \brief Priority for a constant value (e.g., enumerator).
     55   CCP_Constant = 65,
     56   /// \brief Priority for a preprocessor macro.
     57   CCP_Macro = 70,
     58   /// \brief Priority for a nested-name-specifier.
     59   CCP_NestedNameSpecifier = 75,
     60   /// \brief Priority for a result that isn't likely to be what the user wants,
     61   /// but is included for completeness.
     62   CCP_Unlikely = 80,
     63 
     64   /// \brief Priority for the Objective-C "_cmd" implicit parameter.
     65   CCP_ObjC_cmd = CCP_Unlikely
     66 };
     67 
     68 /// \brief Priority value deltas that are added to code-completion results
     69 /// based on the context of the result.
     70 enum {
     71   /// \brief The result is in a base class.
     72   CCD_InBaseClass = 2,
     73   /// \brief The result is a C++ non-static member function whose qualifiers
     74   /// exactly match the object type on which the member function can be called.
     75   CCD_ObjectQualifierMatch = -1,
     76   /// \brief The selector of the given message exactly matches the selector
     77   /// of the current method, which might imply that some kind of delegation
     78   /// is occurring.
     79   CCD_SelectorMatch = -3,
     80 
     81   /// \brief Adjustment to the "bool" type in Objective-C, where the typedef
     82   /// "BOOL" is preferred.
     83   CCD_bool_in_ObjC = 1,
     84 
     85   /// \brief Adjustment for KVC code pattern priorities when it doesn't look
     86   /// like the
     87   CCD_ProbablyNotObjCCollection = 15,
     88 
     89   /// \brief An Objective-C method being used as a property.
     90   CCD_MethodAsProperty = 2
     91 };
     92 
     93 /// \brief Priority value factors by which we will divide or multiply the
     94 /// priority of a code-completion result.
     95 enum {
     96   /// \brief Divide by this factor when a code-completion result's type exactly
     97   /// matches the type we expect.
     98   CCF_ExactTypeMatch = 4,
     99   /// \brief Divide by this factor when a code-completion result's type is
    100   /// similar to the type we expect (e.g., both arithmetic types, both
    101   /// Objective-C object pointer types).
    102   CCF_SimilarTypeMatch = 2
    103 };
    104 
    105 /// \brief A simplified classification of types used when determining
    106 /// "similar" types for code completion.
    107 enum SimplifiedTypeClass {
    108   STC_Arithmetic,
    109   STC_Array,
    110   STC_Block,
    111   STC_Function,
    112   STC_ObjectiveC,
    113   STC_Other,
    114   STC_Pointer,
    115   STC_Record,
    116   STC_Void
    117 };
    118 
    119 /// \brief Determine the simplified type class of the given canonical type.
    120 SimplifiedTypeClass getSimplifiedTypeClass(CanQualType T);
    121 
    122 /// \brief Determine the type that this declaration will have if it is used
    123 /// as a type or in an expression.
    124 QualType getDeclUsageType(ASTContext &C, NamedDecl *ND);
    125 
    126 /// \brief Determine the priority to be given to a macro code completion result
    127 /// with the given name.
    128 ///
    129 /// \param MacroName The name of the macro.
    130 ///
    131 /// \param LangOpts Options describing the current language dialect.
    132 ///
    133 /// \param PreferredTypeIsPointer Whether the preferred type for the context
    134 /// of this macro is a pointer type.
    135 unsigned getMacroUsagePriority(StringRef MacroName,
    136                                const LangOptions &LangOpts,
    137                                bool PreferredTypeIsPointer = false);
    138 
    139 /// \brief Determine the libclang cursor kind associated with the given
    140 /// declaration.
    141 CXCursorKind getCursorKindForDecl(Decl *D);
    142 
    143 class FunctionDecl;
    144 class FunctionType;
    145 class FunctionTemplateDecl;
    146 class IdentifierInfo;
    147 class NamedDecl;
    148 class NestedNameSpecifier;
    149 class Sema;
    150 
    151 /// \brief The context in which code completion occurred, so that the
    152 /// code-completion consumer can process the results accordingly.
    153 class CodeCompletionContext {
    154 public:
    155   enum Kind {
    156     /// \brief An unspecified code-completion context.
    157     CCC_Other,
    158     /// \brief An unspecified code-completion context where we should also add
    159     /// macro completions.
    160     CCC_OtherWithMacros,
    161     /// \brief Code completion occurred within a "top-level" completion context,
    162     /// e.g., at namespace or global scope.
    163     CCC_TopLevel,
    164     /// \brief Code completion occurred within an Objective-C interface,
    165     /// protocol, or category interface.
    166     CCC_ObjCInterface,
    167     /// \brief Code completion occurred within an Objective-C implementation
    168     /// or category implementation.
    169     CCC_ObjCImplementation,
    170     /// \brief Code completion occurred within the instance variable list of
    171     /// an Objective-C interface, implementation, or category implementation.
    172     CCC_ObjCIvarList,
    173     /// \brief Code completion occurred within a class, struct, or union.
    174     CCC_ClassStructUnion,
    175     /// \brief Code completion occurred where a statement (or declaration) is
    176     /// expected in a function, method, or block.
    177     CCC_Statement,
    178     /// \brief Code completion occurred where an expression is expected.
    179     CCC_Expression,
    180     /// \brief Code completion occurred where an Objective-C message receiver
    181     /// is expected.
    182     CCC_ObjCMessageReceiver,
    183     /// \brief Code completion occurred on the right-hand side of a member
    184     /// access expression using the dot operator.
    185     ///
    186     /// The results of this completion are the members of the type being
    187     /// accessed. The type itself is available via
    188     /// \c CodeCompletionContext::getType().
    189     CCC_DotMemberAccess,
    190     /// \brief Code completion occurred on the right-hand side of a member
    191     /// access expression using the arrow operator.
    192     ///
    193     /// The results of this completion are the members of the type being
    194     /// accessed. The type itself is available via
    195     /// \c CodeCompletionContext::getType().
    196     CCC_ArrowMemberAccess,
    197     /// \brief Code completion occurred on the right-hand side of an Objective-C
    198     /// property access expression.
    199     ///
    200     /// The results of this completion are the members of the type being
    201     /// accessed. The type itself is available via
    202     /// \c CodeCompletionContext::getType().
    203     CCC_ObjCPropertyAccess,
    204     /// \brief Code completion occurred after the "enum" keyword, to indicate
    205     /// an enumeration name.
    206     CCC_EnumTag,
    207     /// \brief Code completion occurred after the "union" keyword, to indicate
    208     /// a union name.
    209     CCC_UnionTag,
    210     /// \brief Code completion occurred after the "struct" or "class" keyword,
    211     /// to indicate a struct or class name.
    212     CCC_ClassOrStructTag,
    213     /// \brief Code completion occurred where a protocol name is expected.
    214     CCC_ObjCProtocolName,
    215     /// \brief Code completion occurred where a namespace or namespace alias
    216     /// is expected.
    217     CCC_Namespace,
    218     /// \brief Code completion occurred where a type name is expected.
    219     CCC_Type,
    220     /// \brief Code completion occurred where a new name is expected.
    221     CCC_Name,
    222     /// \brief Code completion occurred where a new name is expected and a
    223     /// qualified name is permissible.
    224     CCC_PotentiallyQualifiedName,
    225     /// \brief Code completion occurred where an macro is being defined.
    226     CCC_MacroName,
    227     /// \brief Code completion occurred where a macro name is expected
    228     /// (without any arguments, in the case of a function-like macro).
    229     CCC_MacroNameUse,
    230     /// \brief Code completion occurred within a preprocessor expression.
    231     CCC_PreprocessorExpression,
    232     /// \brief Code completion occurred where a preprocessor directive is
    233     /// expected.
    234     CCC_PreprocessorDirective,
    235     /// \brief Code completion occurred in a context where natural language is
    236     /// expected, e.g., a comment or string literal.
    237     ///
    238     /// This context usually implies that no completions should be added,
    239     /// unless they come from an appropriate natural-language dictionary.
    240     CCC_NaturalLanguage,
    241     /// \brief Code completion for a selector, as in an \@selector expression.
    242     CCC_SelectorName,
    243     /// \brief Code completion within a type-qualifier list.
    244     CCC_TypeQualifiers,
    245     /// \brief Code completion in a parenthesized expression, which means that
    246     /// we may also have types here in C and Objective-C (as well as in C++).
    247     CCC_ParenthesizedExpression,
    248     /// \brief Code completion where an Objective-C instance message is expcted.
    249     CCC_ObjCInstanceMessage,
    250     /// \brief Code completion where an Objective-C class message is expected.
    251     CCC_ObjCClassMessage,
    252     /// \brief Code completion where the name of an Objective-C class is
    253     /// expected.
    254     CCC_ObjCInterfaceName,
    255     /// \brief Code completion where an Objective-C category name is expected.
    256     CCC_ObjCCategoryName,
    257     /// \brief An unknown context, in which we are recovering from a parsing
    258     /// error and don't know which completions we should give.
    259     CCC_Recovery
    260   };
    261 
    262 private:
    263   enum Kind Kind;
    264 
    265   /// \brief The type that would prefer to see at this point (e.g., the type
    266   /// of an initializer or function parameter).
    267   QualType PreferredType;
    268 
    269   /// \brief The type of the base object in a member access expression.
    270   QualType BaseType;
    271 
    272   /// \brief The identifiers for Objective-C selector parts.
    273   IdentifierInfo **SelIdents;
    274 
    275   /// \brief The number of Objective-C selector parts.
    276   unsigned NumSelIdents;
    277 
    278 public:
    279   /// \brief Construct a new code-completion context of the given kind.
    280   CodeCompletionContext(enum Kind Kind) : Kind(Kind), SelIdents(NULL),
    281                                           NumSelIdents(0) { }
    282 
    283   /// \brief Construct a new code-completion context of the given kind.
    284   CodeCompletionContext(enum Kind Kind, QualType T,
    285                         IdentifierInfo **SelIdents = NULL,
    286                         unsigned NumSelIdents = 0) : Kind(Kind),
    287                                                      SelIdents(SelIdents),
    288                                                     NumSelIdents(NumSelIdents) {
    289     if (Kind == CCC_DotMemberAccess || Kind == CCC_ArrowMemberAccess ||
    290         Kind == CCC_ObjCPropertyAccess || Kind == CCC_ObjCClassMessage ||
    291         Kind == CCC_ObjCInstanceMessage)
    292       BaseType = T;
    293     else
    294       PreferredType = T;
    295   }
    296 
    297   /// \brief Retrieve the kind of code-completion context.
    298   enum Kind getKind() const { return Kind; }
    299 
    300   /// \brief Retrieve the type that this expression would prefer to have, e.g.,
    301   /// if the expression is a variable initializer or a function argument, the
    302   /// type of the corresponding variable or function parameter.
    303   QualType getPreferredType() const { return PreferredType; }
    304 
    305   /// \brief Retrieve the type of the base object in a member-access
    306   /// expression.
    307   QualType getBaseType() const { return BaseType; }
    308 
    309   /// \brief Retrieve the Objective-C selector identifiers.
    310   IdentifierInfo **getSelIdents() const { return SelIdents; }
    311 
    312   /// \brief Retrieve the number of Objective-C selector identifiers.
    313   unsigned getNumSelIdents() const { return NumSelIdents; }
    314 
    315   /// \brief Determines whether we want C++ constructors as results within this
    316   /// context.
    317   bool wantConstructorResults() const;
    318 };
    319 
    320 
    321 /// \brief A "string" used to describe how code completion can
    322 /// be performed for an entity.
    323 ///
    324 /// A code completion string typically shows how a particular entity can be
    325 /// used. For example, the code completion string for a function would show
    326 /// the syntax to call it, including the parentheses, placeholders for the
    327 /// arguments, etc.
    328 class CodeCompletionString {
    329 public:
    330   /// \brief The different kinds of "chunks" that can occur within a code
    331   /// completion string.
    332   enum ChunkKind {
    333     /// \brief The piece of text that the user is expected to type to
    334     /// match the code-completion string, typically a keyword or the name of a
    335     /// declarator or macro.
    336     CK_TypedText,
    337     /// \brief A piece of text that should be placed in the buffer, e.g.,
    338     /// parentheses or a comma in a function call.
    339     CK_Text,
    340     /// \brief A code completion string that is entirely optional. For example,
    341     /// an optional code completion string that describes the default arguments
    342     /// in a function call.
    343     CK_Optional,
    344     /// \brief A string that acts as a placeholder for, e.g., a function
    345     /// call argument.
    346     CK_Placeholder,
    347     /// \brief A piece of text that describes something about the result but
    348     /// should not be inserted into the buffer.
    349     CK_Informative,
    350     /// \brief A piece of text that describes the type of an entity or, for
    351     /// functions and methods, the return type.
    352     CK_ResultType,
    353     /// \brief A piece of text that describes the parameter that corresponds
    354     /// to the code-completion location within a function call, message send,
    355     /// macro invocation, etc.
    356     CK_CurrentParameter,
    357     /// \brief A left parenthesis ('(').
    358     CK_LeftParen,
    359     /// \brief A right parenthesis (')').
    360     CK_RightParen,
    361     /// \brief A left bracket ('[').
    362     CK_LeftBracket,
    363     /// \brief A right bracket (']').
    364     CK_RightBracket,
    365     /// \brief A left brace ('{').
    366     CK_LeftBrace,
    367     /// \brief A right brace ('}').
    368     CK_RightBrace,
    369     /// \brief A left angle bracket ('<').
    370     CK_LeftAngle,
    371     /// \brief A right angle bracket ('>').
    372     CK_RightAngle,
    373     /// \brief A comma separator (',').
    374     CK_Comma,
    375     /// \brief A colon (':').
    376     CK_Colon,
    377     /// \brief A semicolon (';').
    378     CK_SemiColon,
    379     /// \brief An '=' sign.
    380     CK_Equal,
    381     /// \brief Horizontal whitespace (' ').
    382     CK_HorizontalSpace,
    383     /// \brief Vertical whitespace ('\\n' or '\\r\\n', depending on the
    384     /// platform).
    385     CK_VerticalSpace
    386   };
    387 
    388   /// \brief One piece of the code completion string.
    389   struct Chunk {
    390     /// \brief The kind of data stored in this piece of the code completion
    391     /// string.
    392     ChunkKind Kind;
    393 
    394     union {
    395       /// \brief The text string associated with a CK_Text, CK_Placeholder,
    396       /// CK_Informative, or CK_Comma chunk.
    397       /// The string is owned by the chunk and will be deallocated
    398       /// (with delete[]) when the chunk is destroyed.
    399       const char *Text;
    400 
    401       /// \brief The code completion string associated with a CK_Optional chunk.
    402       /// The optional code completion string is owned by the chunk, and will
    403       /// be deallocated (with delete) when the chunk is destroyed.
    404       CodeCompletionString *Optional;
    405     };
    406 
    407     Chunk() : Kind(CK_Text), Text(0) { }
    408 
    409     explicit Chunk(ChunkKind Kind, const char *Text = "");
    410 
    411     /// \brief Create a new text chunk.
    412     static Chunk CreateText(const char *Text);
    413 
    414     /// \brief Create a new optional chunk.
    415     static Chunk CreateOptional(CodeCompletionString *Optional);
    416 
    417     /// \brief Create a new placeholder chunk.
    418     static Chunk CreatePlaceholder(const char *Placeholder);
    419 
    420     /// \brief Create a new informative chunk.
    421     static Chunk CreateInformative(const char *Informative);
    422 
    423     /// \brief Create a new result type chunk.
    424     static Chunk CreateResultType(const char *ResultType);
    425 
    426     /// \brief Create a new current-parameter chunk.
    427     static Chunk CreateCurrentParameter(const char *CurrentParameter);
    428   };
    429 
    430 private:
    431   /// \brief The number of chunks stored in this string.
    432   unsigned NumChunks : 16;
    433 
    434   /// \brief The number of annotations for this code-completion result.
    435   unsigned NumAnnotations : 16;
    436 
    437   /// \brief The priority of this code-completion string.
    438   unsigned Priority : 16;
    439 
    440   /// \brief The availability of this code-completion result.
    441   unsigned Availability : 2;
    442 
    443   /// \brief The kind of the parent context.
    444   unsigned ParentKind : 14;
    445 
    446   /// \brief The name of the parent context.
    447   StringRef ParentName;
    448 
    449   /// \brief A brief documentation comment attached to the declaration of
    450   /// entity being completed by this result.
    451   const char *BriefComment;
    452 
    453   CodeCompletionString(const CodeCompletionString &); // DO NOT IMPLEMENT
    454   CodeCompletionString &operator=(const CodeCompletionString &); // DITTO
    455 
    456   CodeCompletionString(const Chunk *Chunks, unsigned NumChunks,
    457                        unsigned Priority, CXAvailabilityKind Availability,
    458                        const char **Annotations, unsigned NumAnnotations,
    459                        CXCursorKind ParentKind, StringRef ParentName,
    460                        const char *BriefComment);
    461   ~CodeCompletionString() { }
    462 
    463   friend class CodeCompletionBuilder;
    464   friend class CodeCompletionResult;
    465 
    466 public:
    467   typedef const Chunk *iterator;
    468   iterator begin() const { return reinterpret_cast<const Chunk *>(this + 1); }
    469   iterator end() const { return begin() + NumChunks; }
    470   bool empty() const { return NumChunks == 0; }
    471   unsigned size() const { return NumChunks; }
    472 
    473   const Chunk &operator[](unsigned I) const {
    474     assert(I < size() && "Chunk index out-of-range");
    475     return begin()[I];
    476   }
    477 
    478   /// \brief Returns the text in the TypedText chunk.
    479   const char *getTypedText() const;
    480 
    481   /// \brief Retrieve the priority of this code completion result.
    482   unsigned getPriority() const { return Priority; }
    483 
    484   /// \brief Retrieve the availability of this code completion result.
    485   unsigned getAvailability() const { return Availability; }
    486 
    487   /// \brief Retrieve the number of annotations for this code completion result.
    488   unsigned getAnnotationCount() const;
    489 
    490   /// \brief Retrieve the annotation string specified by \c AnnotationNr.
    491   const char *getAnnotation(unsigned AnnotationNr) const;
    492 
    493   /// \brief Retrieve parent context's cursor kind.
    494   CXCursorKind getParentContextKind() const {
    495     return (CXCursorKind)ParentKind;
    496   }
    497 
    498   /// \brief Retrieve the name of the parent context.
    499   StringRef getParentContextName() const {
    500     return ParentName;
    501   }
    502 
    503   const char *getBriefComment() const {
    504     return BriefComment;
    505   }
    506 
    507   /// \brief Retrieve a string representation of the code completion string,
    508   /// which is mainly useful for debugging.
    509   std::string getAsString() const;
    510 };
    511 
    512 /// \brief An allocator used specifically for the purpose of code completion.
    513 class CodeCompletionAllocator : public llvm::BumpPtrAllocator {
    514 public:
    515   /// \brief Copy the given string into this allocator.
    516   const char *CopyString(StringRef String);
    517 
    518   /// \brief Copy the given string into this allocator.
    519   const char *CopyString(Twine String);
    520 
    521   // \brief Copy the given string into this allocator.
    522   const char *CopyString(const char *String) {
    523     return CopyString(StringRef(String));
    524   }
    525 
    526   /// \brief Copy the given string into this allocator.
    527   const char *CopyString(const std::string &String) {
    528     return CopyString(StringRef(String));
    529   }
    530 };
    531 
    532 /// \brief Allocator for a cached set of global code completions.
    533 class GlobalCodeCompletionAllocator
    534   : public CodeCompletionAllocator,
    535     public RefCountedBase<GlobalCodeCompletionAllocator>
    536 {
    537 
    538 };
    539 
    540 class CodeCompletionTUInfo {
    541   llvm::DenseMap<DeclContext *, StringRef> ParentNames;
    542   IntrusiveRefCntPtr<GlobalCodeCompletionAllocator> AllocatorRef;
    543 
    544 public:
    545   explicit CodeCompletionTUInfo(
    546                     IntrusiveRefCntPtr<GlobalCodeCompletionAllocator> Allocator)
    547     : AllocatorRef(Allocator) { }
    548 
    549   IntrusiveRefCntPtr<GlobalCodeCompletionAllocator> getAllocatorRef() const {
    550     return AllocatorRef;
    551   }
    552   CodeCompletionAllocator &getAllocator() const {
    553     assert(AllocatorRef);
    554     return *AllocatorRef;
    555   }
    556 
    557   StringRef getParentName(DeclContext *DC);
    558 };
    559 
    560 } // end namespace clang
    561 
    562 namespace llvm {
    563   template <> struct isPodLike<clang::CodeCompletionString::Chunk> {
    564     static const bool value = true;
    565   };
    566 }
    567 
    568 namespace clang {
    569 
    570 /// \brief A builder class used to construct new code-completion strings.
    571 class CodeCompletionBuilder {
    572 public:
    573   typedef CodeCompletionString::Chunk Chunk;
    574 
    575 private:
    576   CodeCompletionAllocator &Allocator;
    577   CodeCompletionTUInfo &CCTUInfo;
    578   unsigned Priority;
    579   CXAvailabilityKind Availability;
    580   CXCursorKind ParentKind;
    581   StringRef ParentName;
    582   const char *BriefComment;
    583 
    584   /// \brief The chunks stored in this string.
    585   SmallVector<Chunk, 4> Chunks;
    586 
    587   SmallVector<const char *, 2> Annotations;
    588 
    589 public:
    590   CodeCompletionBuilder(CodeCompletionAllocator &Allocator,
    591                         CodeCompletionTUInfo &CCTUInfo)
    592     : Allocator(Allocator), CCTUInfo(CCTUInfo),
    593       Priority(0), Availability(CXAvailability_Available),
    594       ParentKind(CXCursor_NotImplemented), BriefComment(NULL) { }
    595 
    596   CodeCompletionBuilder(CodeCompletionAllocator &Allocator,
    597                         CodeCompletionTUInfo &CCTUInfo,
    598                         unsigned Priority, CXAvailabilityKind Availability)
    599     : Allocator(Allocator), CCTUInfo(CCTUInfo),
    600       Priority(Priority), Availability(Availability),
    601       ParentKind(CXCursor_NotImplemented), BriefComment(NULL) { }
    602 
    603   /// \brief Retrieve the allocator into which the code completion
    604   /// strings should be allocated.
    605   CodeCompletionAllocator &getAllocator() const { return Allocator; }
    606 
    607   CodeCompletionTUInfo &getCodeCompletionTUInfo() const { return CCTUInfo; }
    608 
    609   /// \brief Take the resulting completion string.
    610   ///
    611   /// This operation can only be performed once.
    612   CodeCompletionString *TakeString();
    613 
    614   /// \brief Add a new typed-text chunk.
    615   void AddTypedTextChunk(const char *Text);
    616 
    617   /// \brief Add a new text chunk.
    618   void AddTextChunk(const char *Text);
    619 
    620   /// \brief Add a new optional chunk.
    621   void AddOptionalChunk(CodeCompletionString *Optional);
    622 
    623   /// \brief Add a new placeholder chunk.
    624   void AddPlaceholderChunk(const char *Placeholder);
    625 
    626   /// \brief Add a new informative chunk.
    627   void AddInformativeChunk(const char *Text);
    628 
    629   /// \brief Add a new result-type chunk.
    630   void AddResultTypeChunk(const char *ResultType);
    631 
    632   /// \brief Add a new current-parameter chunk.
    633   void AddCurrentParameterChunk(const char *CurrentParameter);
    634 
    635   /// \brief Add a new chunk.
    636   void AddChunk(CodeCompletionString::ChunkKind CK, const char *Text = "");
    637 
    638   void AddAnnotation(const char *A) { Annotations.push_back(A); }
    639 
    640   /// \brief Add the parent context information to this code completion.
    641   void addParentContext(DeclContext *DC);
    642 
    643   void addBriefComment(StringRef Comment);
    644 
    645   CXCursorKind getParentKind() const { return ParentKind; }
    646   StringRef getParentName() const { return ParentName; }
    647 };
    648 
    649 /// \brief Captures a result of code completion.
    650 class CodeCompletionResult {
    651 public:
    652   /// \brief Describes the kind of result generated.
    653   enum ResultKind {
    654     RK_Declaration = 0, ///< Refers to a declaration
    655     RK_Keyword,         ///< Refers to a keyword or symbol.
    656     RK_Macro,           ///< Refers to a macro
    657     RK_Pattern          ///< Refers to a precomputed pattern.
    658   };
    659 
    660   /// \brief When Kind == RK_Declaration or RK_Pattern, the declaration we are
    661   /// referring to. In the latter case, the declaration might be NULL.
    662   NamedDecl *Declaration;
    663 
    664   union {
    665     /// \brief When Kind == RK_Keyword, the string representing the keyword
    666     /// or symbol's spelling.
    667     const char *Keyword;
    668 
    669     /// \brief When Kind == RK_Pattern, the code-completion string that
    670     /// describes the completion text to insert.
    671     CodeCompletionString *Pattern;
    672 
    673     /// \brief When Kind == RK_Macro, the identifier that refers to a macro.
    674     IdentifierInfo *Macro;
    675   };
    676 
    677   /// \brief The priority of this particular code-completion result.
    678   unsigned Priority;
    679 
    680   /// \brief Specifies which parameter (of a function, Objective-C method,
    681   /// macro, etc.) we should start with when formatting the result.
    682   unsigned StartParameter;
    683 
    684   /// \brief The kind of result stored here.
    685   ResultKind Kind;
    686 
    687   /// \brief The cursor kind that describes this result.
    688   CXCursorKind CursorKind;
    689 
    690   /// \brief The availability of this result.
    691   CXAvailabilityKind Availability;
    692 
    693   /// \brief Whether this result is hidden by another name.
    694   bool Hidden : 1;
    695 
    696   /// \brief Whether this result was found via lookup into a base class.
    697   bool QualifierIsInformative : 1;
    698 
    699   /// \brief Whether this declaration is the beginning of a
    700   /// nested-name-specifier and, therefore, should be followed by '::'.
    701   bool StartsNestedNameSpecifier : 1;
    702 
    703   /// \brief Whether all parameters (of a function, Objective-C
    704   /// method, etc.) should be considered "informative".
    705   bool AllParametersAreInformative : 1;
    706 
    707   /// \brief Whether we're completing a declaration of the given entity,
    708   /// rather than a use of that entity.
    709   bool DeclaringEntity : 1;
    710 
    711   /// \brief If the result should have a nested-name-specifier, this is it.
    712   /// When \c QualifierIsInformative, the nested-name-specifier is
    713   /// informative rather than required.
    714   NestedNameSpecifier *Qualifier;
    715 
    716   /// \brief Build a result that refers to a declaration.
    717   CodeCompletionResult(NamedDecl *Declaration,
    718                        NestedNameSpecifier *Qualifier = 0,
    719                        bool QualifierIsInformative = false,
    720                        bool Accessible = true)
    721     : Declaration(Declaration), Priority(getPriorityFromDecl(Declaration)),
    722       StartParameter(0), Kind(RK_Declaration),
    723       Availability(CXAvailability_Available), Hidden(false),
    724       QualifierIsInformative(QualifierIsInformative),
    725       StartsNestedNameSpecifier(false), AllParametersAreInformative(false),
    726       DeclaringEntity(false), Qualifier(Qualifier) {
    727     computeCursorKindAndAvailability(Accessible);
    728   }
    729 
    730   /// \brief Build a result that refers to a keyword or symbol.
    731   CodeCompletionResult(const char *Keyword, unsigned Priority = CCP_Keyword)
    732     : Declaration(0), Keyword(Keyword), Priority(Priority), StartParameter(0),
    733       Kind(RK_Keyword), CursorKind(CXCursor_NotImplemented),
    734       Availability(CXAvailability_Available), Hidden(false),
    735       QualifierIsInformative(0), StartsNestedNameSpecifier(false),
    736       AllParametersAreInformative(false), DeclaringEntity(false), Qualifier(0)
    737   {
    738   }
    739 
    740   /// \brief Build a result that refers to a macro.
    741   CodeCompletionResult(IdentifierInfo *Macro, unsigned Priority = CCP_Macro)
    742     : Declaration(0), Macro(Macro), Priority(Priority), StartParameter(0),
    743       Kind(RK_Macro), CursorKind(CXCursor_MacroDefinition),
    744       Availability(CXAvailability_Available), Hidden(false),
    745       QualifierIsInformative(0), StartsNestedNameSpecifier(false),
    746       AllParametersAreInformative(false), DeclaringEntity(false), Qualifier(0)
    747   {
    748   }
    749 
    750   /// \brief Build a result that refers to a pattern.
    751   CodeCompletionResult(CodeCompletionString *Pattern,
    752                        unsigned Priority = CCP_CodePattern,
    753                        CXCursorKind CursorKind = CXCursor_NotImplemented,
    754                    CXAvailabilityKind Availability = CXAvailability_Available,
    755                        NamedDecl *D = 0)
    756     : Declaration(D), Pattern(Pattern), Priority(Priority), StartParameter(0),
    757       Kind(RK_Pattern), CursorKind(CursorKind), Availability(Availability),
    758       Hidden(false), QualifierIsInformative(0),
    759       StartsNestedNameSpecifier(false), AllParametersAreInformative(false),
    760       DeclaringEntity(false), Qualifier(0)
    761   {
    762   }
    763 
    764   /// \brief Build a result that refers to a pattern with an associated
    765   /// declaration.
    766   CodeCompletionResult(CodeCompletionString *Pattern, NamedDecl *D,
    767                        unsigned Priority)
    768     : Declaration(D), Pattern(Pattern), Priority(Priority), StartParameter(0),
    769       Kind(RK_Pattern), Availability(CXAvailability_Available), Hidden(false),
    770       QualifierIsInformative(false), StartsNestedNameSpecifier(false),
    771       AllParametersAreInformative(false), DeclaringEntity(false), Qualifier(0) {
    772     computeCursorKindAndAvailability();
    773   }
    774 
    775   /// \brief Retrieve the declaration stored in this result.
    776   NamedDecl *getDeclaration() const {
    777     assert(Kind == RK_Declaration && "Not a declaration result");
    778     return Declaration;
    779   }
    780 
    781   /// \brief Retrieve the keyword stored in this result.
    782   const char *getKeyword() const {
    783     assert(Kind == RK_Keyword && "Not a keyword result");
    784     return Keyword;
    785   }
    786 
    787   /// \brief Create a new code-completion string that describes how to insert
    788   /// this result into a program.
    789   ///
    790   /// \param S The semantic analysis that created the result.
    791   ///
    792   /// \param Allocator The allocator that will be used to allocate the
    793   /// string itself.
    794   CodeCompletionString *CreateCodeCompletionString(Sema &S,
    795                                            CodeCompletionAllocator &Allocator,
    796                                            CodeCompletionTUInfo &CCTUInfo,
    797                                            bool IncludeBriefComments);
    798   CodeCompletionString *CreateCodeCompletionString(ASTContext &Ctx,
    799                                                    Preprocessor &PP,
    800                                            CodeCompletionAllocator &Allocator,
    801                                            CodeCompletionTUInfo &CCTUInfo,
    802                                            bool IncludeBriefComments);
    803 
    804   /// \brief Determine a base priority for the given declaration.
    805   static unsigned getPriorityFromDecl(NamedDecl *ND);
    806 
    807 private:
    808   void computeCursorKindAndAvailability(bool Accessible = true);
    809 };
    810 
    811 bool operator<(const CodeCompletionResult &X, const CodeCompletionResult &Y);
    812 
    813 inline bool operator>(const CodeCompletionResult &X,
    814                       const CodeCompletionResult &Y) {
    815   return Y < X;
    816 }
    817 
    818 inline bool operator<=(const CodeCompletionResult &X,
    819                       const CodeCompletionResult &Y) {
    820   return !(Y < X);
    821 }
    822 
    823 inline bool operator>=(const CodeCompletionResult &X,
    824                        const CodeCompletionResult &Y) {
    825   return !(X < Y);
    826 }
    827 
    828 
    829 raw_ostream &operator<<(raw_ostream &OS,
    830                               const CodeCompletionString &CCS);
    831 
    832 /// \brief Abstract interface for a consumer of code-completion
    833 /// information.
    834 class CodeCompleteConsumer {
    835 protected:
    836   const CodeCompleteOptions CodeCompleteOpts;
    837 
    838   /// \brief Whether the output format for the code-completion consumer is
    839   /// binary.
    840   bool OutputIsBinary;
    841 
    842 public:
    843   class OverloadCandidate {
    844   public:
    845     /// \brief Describes the type of overload candidate.
    846     enum CandidateKind {
    847       /// \brief The candidate is a function declaration.
    848       CK_Function,
    849       /// \brief The candidate is a function template.
    850       CK_FunctionTemplate,
    851       /// \brief The "candidate" is actually a variable, expression, or block
    852       /// for which we only have a function prototype.
    853       CK_FunctionType
    854     };
    855 
    856   private:
    857     /// \brief The kind of overload candidate.
    858     CandidateKind Kind;
    859 
    860     union {
    861       /// \brief The function overload candidate, available when
    862       /// Kind == CK_Function.
    863       FunctionDecl *Function;
    864 
    865       /// \brief The function template overload candidate, available when
    866       /// Kind == CK_FunctionTemplate.
    867       FunctionTemplateDecl *FunctionTemplate;
    868 
    869       /// \brief The function type that describes the entity being called,
    870       /// when Kind == CK_FunctionType.
    871       const FunctionType *Type;
    872     };
    873 
    874   public:
    875     OverloadCandidate(FunctionDecl *Function)
    876       : Kind(CK_Function), Function(Function) { }
    877 
    878     OverloadCandidate(FunctionTemplateDecl *FunctionTemplateDecl)
    879       : Kind(CK_FunctionTemplate), FunctionTemplate(FunctionTemplateDecl) { }
    880 
    881     OverloadCandidate(const FunctionType *Type)
    882       : Kind(CK_FunctionType), Type(Type) { }
    883 
    884     /// \brief Determine the kind of overload candidate.
    885     CandidateKind getKind() const { return Kind; }
    886 
    887     /// \brief Retrieve the function overload candidate or the templated
    888     /// function declaration for a function template.
    889     FunctionDecl *getFunction() const;
    890 
    891     /// \brief Retrieve the function template overload candidate.
    892     FunctionTemplateDecl *getFunctionTemplate() const {
    893       assert(getKind() == CK_FunctionTemplate && "Not a function template");
    894       return FunctionTemplate;
    895     }
    896 
    897     /// \brief Retrieve the function type of the entity, regardless of how the
    898     /// function is stored.
    899     const FunctionType *getFunctionType() const;
    900 
    901     /// \brief Create a new code-completion string that describes the function
    902     /// signature of this overload candidate.
    903     CodeCompletionString *CreateSignatureString(unsigned CurrentArg,
    904                                                 Sema &S,
    905                                       CodeCompletionAllocator &Allocator,
    906                                       CodeCompletionTUInfo &CCTUInfo) const;
    907   };
    908 
    909   CodeCompleteConsumer(const CodeCompleteOptions &CodeCompleteOpts,
    910                        bool OutputIsBinary)
    911     : CodeCompleteOpts(CodeCompleteOpts), OutputIsBinary(OutputIsBinary)
    912   { }
    913 
    914   /// \brief Whether the code-completion consumer wants to see macros.
    915   bool includeMacros() const {
    916     return CodeCompleteOpts.IncludeMacros;
    917   }
    918 
    919   /// \brief Whether the code-completion consumer wants to see code patterns.
    920   bool includeCodePatterns() const {
    921     return CodeCompleteOpts.IncludeCodePatterns;
    922   }
    923 
    924   /// \brief Whether to include global (top-level) declaration results.
    925   bool includeGlobals() const {
    926     return CodeCompleteOpts.IncludeGlobals;
    927   }
    928 
    929   /// \brief Whether to include brief documentation comments within the set of
    930   /// code completions returned.
    931   bool includeBriefComments() const {
    932     return CodeCompleteOpts.IncludeBriefComments;
    933   }
    934 
    935   /// \brief Determine whether the output of this consumer is binary.
    936   bool isOutputBinary() const { return OutputIsBinary; }
    937 
    938   /// \brief Deregisters and destroys this code-completion consumer.
    939   virtual ~CodeCompleteConsumer();
    940 
    941   /// \name Code-completion callbacks
    942   //@{
    943   /// \brief Process the finalized code-completion results.
    944   virtual void ProcessCodeCompleteResults(Sema &S,
    945                                           CodeCompletionContext Context,
    946                                           CodeCompletionResult *Results,
    947                                           unsigned NumResults) { }
    948 
    949   /// \param S the semantic-analyzer object for which code-completion is being
    950   /// done.
    951   ///
    952   /// \param CurrentArg the index of the current argument.
    953   ///
    954   /// \param Candidates an array of overload candidates.
    955   ///
    956   /// \param NumCandidates the number of overload candidates
    957   virtual void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
    958                                          OverloadCandidate *Candidates,
    959                                          unsigned NumCandidates) { }
    960   //@}
    961 
    962   /// \brief Retrieve the allocator that will be used to allocate
    963   /// code completion strings.
    964   virtual CodeCompletionAllocator &getAllocator() = 0;
    965 
    966   virtual CodeCompletionTUInfo &getCodeCompletionTUInfo() = 0;
    967 };
    968 
    969 /// \brief A simple code-completion consumer that prints the results it
    970 /// receives in a simple format.
    971 class PrintingCodeCompleteConsumer : public CodeCompleteConsumer {
    972   /// \brief The raw output stream.
    973   raw_ostream &OS;
    974 
    975   CodeCompletionTUInfo CCTUInfo;
    976 
    977 public:
    978   /// \brief Create a new printing code-completion consumer that prints its
    979   /// results to the given raw output stream.
    980   PrintingCodeCompleteConsumer(const CodeCompleteOptions &CodeCompleteOpts,
    981                                raw_ostream &OS)
    982     : CodeCompleteConsumer(CodeCompleteOpts, false), OS(OS),
    983       CCTUInfo(new GlobalCodeCompletionAllocator) {}
    984 
    985   /// \brief Prints the finalized code-completion results.
    986   virtual void ProcessCodeCompleteResults(Sema &S,
    987                                           CodeCompletionContext Context,
    988                                           CodeCompletionResult *Results,
    989                                           unsigned NumResults);
    990 
    991   virtual void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
    992                                          OverloadCandidate *Candidates,
    993                                          unsigned NumCandidates);
    994 
    995   virtual CodeCompletionAllocator &getAllocator() {
    996     return CCTUInfo.getAllocator();
    997   }
    998 
    999   virtual CodeCompletionTUInfo &getCodeCompletionTUInfo() { return CCTUInfo; }
   1000 };
   1001 
   1002 } // end namespace clang
   1003 
   1004 #endif // LLVM_CLANG_SEMA_CODECOMPLETECONSUMER_H
   1005