Registry.h revision 288943 
1//===--- Registry.h - Matcher registry -----*- 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/// \file
11/// \brief Registry of all known matchers.
12///
13/// The registry provides a generic interface to construct any matcher by name.
14///
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_CLANG_ASTMATCHERS_DYNAMIC_REGISTRY_H
18#define LLVM_CLANG_ASTMATCHERS_DYNAMIC_REGISTRY_H
19
20#include "clang/ASTMatchers/Dynamic/Diagnostics.h"
21#include "clang/ASTMatchers/Dynamic/VariantValue.h"
22#include "clang/Basic/LLVM.h"
23#include "llvm/ADT/ArrayRef.h"
24#include "llvm/ADT/Optional.h"
25#include "llvm/ADT/StringRef.h"
26
27namespace clang {
28namespace ast_matchers {
29namespace dynamic {
30
31namespace internal {
32class MatcherDescriptor;
33}
34
35typedef const internal::MatcherDescriptor *MatcherCtor;
36
37struct MatcherCompletion {
38  MatcherCompletion() {}
39  MatcherCompletion(StringRef TypedText, StringRef MatcherDecl,
40                    unsigned Specificity)
41      : TypedText(TypedText), MatcherDecl(MatcherDecl),
42        Specificity(Specificity) {}
43
44  /// \brief The text to type to select this matcher.
45  std::string TypedText;
46
47  /// \brief The "declaration" of the matcher, with type information.
48  std::string MatcherDecl;
49
50  /// \brief Value corresponding to the "specificity" of the converted matcher.
51  ///
52  /// Zero specificity indicates that this conversion would produce a trivial
53  /// matcher that will either always or never match.
54  /// Such matchers are excluded from code completion results.
55  unsigned Specificity;
56
57  bool operator==(const MatcherCompletion &Other) const {
58    return TypedText == Other.TypedText && MatcherDecl == Other.MatcherDecl;
59  }
60};
61
62class Registry {
63public:
64  /// \brief Look up a matcher in the registry by name,
65  ///
66  /// \return An opaque value which may be used to refer to the matcher
67  /// constructor, or Optional<MatcherCtor>() if not found.
68  static llvm::Optional<MatcherCtor> lookupMatcherCtor(StringRef MatcherName);
69
70  /// \brief Compute the list of completion types for \p Context.
71  ///
72  /// Each element of \p Context represents a matcher invocation, going from
73  /// outermost to innermost. Elements are pairs consisting of a reference to
74  /// the matcher constructor and the index of the next element in the
75  /// argument list of that matcher (or for the last element, the index of
76  /// the completion point in the argument list). An empty list requests
77  /// completion for the root matcher.
78  static std::vector<ArgKind> getAcceptedCompletionTypes(
79      llvm::ArrayRef<std::pair<MatcherCtor, unsigned>> Context);
80
81  /// \brief Compute the list of completions that match any of
82  /// \p AcceptedTypes.
83  ///
84  /// \param AcceptedTypes All types accepted for this completion.
85  ///
86  /// \return All completions for the specified types.
87  /// Completions should be valid when used in \c lookupMatcherCtor().
88  /// The matcher constructed from the return of \c lookupMatcherCtor()
89  /// should be convertible to some type in \p AcceptedTypes.
90  static std::vector<MatcherCompletion>
91  getMatcherCompletions(ArrayRef<ArgKind> AcceptedTypes);
92
93  /// \brief Construct a matcher from the registry.
94  ///
95  /// \param Ctor The matcher constructor to instantiate.
96  ///
97  /// \param NameRange The location of the name in the matcher source.
98  ///   Useful for error reporting.
99  ///
100  /// \param Args The argument list for the matcher. The number and types of the
101  ///   values must be valid for the matcher requested. Otherwise, the function
102  ///   will return an error.
103  ///
104  /// \return The matcher object constructed if no error was found.
105  ///   A null matcher if the number of arguments or argument types do not match
106  ///   the signature.  In that case \c Error will contain the description of
107  ///   the error.
108  static VariantMatcher constructMatcher(MatcherCtor Ctor,
109                                         const SourceRange &NameRange,
110                                         ArrayRef<ParserValue> Args,
111                                         Diagnostics *Error);
112
113  /// \brief Construct a matcher from the registry and bind it.
114  ///
115  /// Similar the \c constructMatcher() above, but it then tries to bind the
116  /// matcher to the specified \c BindID.
117  /// If the matcher is not bindable, it sets an error in \c Error and returns
118  /// a null matcher.
119  static VariantMatcher constructBoundMatcher(MatcherCtor Ctor,
120                                              const SourceRange &NameRange,
121                                              StringRef BindID,
122                                              ArrayRef<ParserValue> Args,
123                                              Diagnostics *Error);
124
125private:
126  Registry() = delete;
127};
128
129}  // namespace dynamic
130}  // namespace ast_matchers
131}  // namespace clang
132
133#endif  // LLVM_CLANG_AST_MATCHERS_DYNAMIC_REGISTRY_H
134