Registry.h revision 341825 
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/// 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 "llvm/ADT/ArrayRef.h"
23#include "llvm/ADT/Optional.h"
24#include "llvm/ADT/StringRef.h"
25#include <string>
26#include <utility>
27#include <vector>
28
29namespace clang {
30namespace ast_matchers {
31namespace dynamic {
32
33namespace internal {
34
35class MatcherDescriptor;
36
37} // namespace internal
38
39using MatcherCtor = const internal::MatcherDescriptor *;
40
41struct MatcherCompletion {
42  MatcherCompletion() = default;
43  MatcherCompletion(StringRef TypedText, StringRef MatcherDecl,
44                    unsigned Specificity)
45      : TypedText(TypedText), MatcherDecl(MatcherDecl),
46        Specificity(Specificity) {}
47
48  bool operator==(const MatcherCompletion &Other) const {
49    return TypedText == Other.TypedText && MatcherDecl == Other.MatcherDecl;
50  }
51
52  /// The text to type to select this matcher.
53  std::string TypedText;
54
55  /// The "declaration" of the matcher, with type information.
56  std::string MatcherDecl;
57
58  /// Value corresponding to the "specificity" of the converted matcher.
59  ///
60  /// Zero specificity indicates that this conversion would produce a trivial
61  /// matcher that will either always or never match.
62  /// Such matchers are excluded from code completion results.
63  unsigned Specificity;
64};
65
66class Registry {
67public:
68  Registry() = delete;
69
70  /// Look up a matcher in the registry by name,
71  ///
72  /// \return An opaque value which may be used to refer to the matcher
73  /// constructor, or Optional<MatcherCtor>() if not found.
74  static llvm::Optional<MatcherCtor> lookupMatcherCtor(StringRef MatcherName);
75
76  /// Compute the list of completion types for \p Context.
77  ///
78  /// Each element of \p Context represents a matcher invocation, going from
79  /// outermost to innermost. Elements are pairs consisting of a reference to
80  /// the matcher constructor and the index of the next element in the
81  /// argument list of that matcher (or for the last element, the index of
82  /// the completion point in the argument list). An empty list requests
83  /// completion for the root matcher.
84  static std::vector<ArgKind> getAcceptedCompletionTypes(
85      llvm::ArrayRef<std::pair<MatcherCtor, unsigned>> Context);
86
87  /// Compute the list of completions that match any of
88  /// \p AcceptedTypes.
89  ///
90  /// \param AcceptedTypes All types accepted for this completion.
91  ///
92  /// \return All completions for the specified types.
93  /// Completions should be valid when used in \c lookupMatcherCtor().
94  /// The matcher constructed from the return of \c lookupMatcherCtor()
95  /// should be convertible to some type in \p AcceptedTypes.
96  static std::vector<MatcherCompletion>
97  getMatcherCompletions(ArrayRef<ArgKind> AcceptedTypes);
98
99  /// Construct a matcher from the registry.
100  ///
101  /// \param Ctor The matcher constructor to instantiate.
102  ///
103  /// \param NameRange The location of the name in the matcher source.
104  ///   Useful for error reporting.
105  ///
106  /// \param Args The argument list for the matcher. The number and types of the
107  ///   values must be valid for the matcher requested. Otherwise, the function
108  ///   will return an error.
109  ///
110  /// \return The matcher object constructed if no error was found.
111  ///   A null matcher if the number of arguments or argument types do not match
112  ///   the signature.  In that case \c Error will contain the description of
113  ///   the error.
114  static VariantMatcher constructMatcher(MatcherCtor Ctor,
115                                         SourceRange NameRange,
116                                         ArrayRef<ParserValue> Args,
117                                         Diagnostics *Error);
118
119  /// Construct a matcher from the registry and bind it.
120  ///
121  /// Similar the \c constructMatcher() above, but it then tries to bind the
122  /// matcher to the specified \c BindID.
123  /// If the matcher is not bindable, it sets an error in \c Error and returns
124  /// a null matcher.
125  static VariantMatcher constructBoundMatcher(MatcherCtor Ctor,
126                                              SourceRange NameRange,
127                                              StringRef BindID,
128                                              ArrayRef<ParserValue> Args,
129                                              Diagnostics *Error);
130};
131
132} // namespace dynamic
133} // namespace ast_matchers
134} // namespace clang
135
136#endif // LLVM_CLANG_AST_MATCHERS_DYNAMIC_REGISTRY_H
137