1//===- Registry.h - Matcher registry ----------------------------*- C++ -*-===//
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/// \file
10/// Registry of all known matchers.
11///
12/// The registry provides a generic interface to construct any matcher by name.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_CLANG_ASTMATCHERS_DYNAMIC_REGISTRY_H
17#define LLVM_CLANG_ASTMATCHERS_DYNAMIC_REGISTRY_H
18
19#include "clang/ASTMatchers/Dynamic/Diagnostics.h"
20#include "clang/ASTMatchers/Dynamic/VariantValue.h"
21#include "llvm/ADT/ArrayRef.h"
22#include "llvm/ADT/Optional.h"
23#include "llvm/ADT/StringRef.h"
24#include <string>
25#include <utility>
26#include <vector>
27
28namespace clang {
29namespace ast_matchers {
30namespace dynamic {
31
32namespace internal {
33
34class MatcherDescriptor;
35
36} // namespace internal
37
38using MatcherCtor = const internal::MatcherDescriptor *;
39
40struct MatcherCompletion {
41  MatcherCompletion() = default;
42  MatcherCompletion(StringRef TypedText, StringRef MatcherDecl,
43                    unsigned Specificity)
44      : TypedText(TypedText), MatcherDecl(MatcherDecl),
45        Specificity(Specificity) {}
46
47  bool operator==(const MatcherCompletion &Other) const {
48    return TypedText == Other.TypedText && MatcherDecl == Other.MatcherDecl;
49  }
50
51  /// The text to type to select this matcher.
52  std::string TypedText;
53
54  /// The "declaration" of the matcher, with type information.
55  std::string MatcherDecl;
56
57  /// Value corresponding to the "specificity" of the converted matcher.
58  ///
59  /// Zero specificity indicates that this conversion would produce a trivial
60  /// matcher that will either always or never match.
61  /// Such matchers are excluded from code completion results.
62  unsigned Specificity;
63};
64
65class Registry {
66public:
67  Registry() = delete;
68
69  /// Look up a matcher in the registry by name,
70  ///
71  /// \return An opaque value which may be used to refer to the matcher
72  /// constructor, or Optional<MatcherCtor>() if not found.
73  static llvm::Optional<MatcherCtor> lookupMatcherCtor(StringRef MatcherName);
74
75  /// Compute the list of completion types for \p Context.
76  ///
77  /// Each element of \p Context represents a matcher invocation, going from
78  /// outermost to innermost. Elements are pairs consisting of a reference to
79  /// the matcher constructor and the index of the next element in the
80  /// argument list of that matcher (or for the last element, the index of
81  /// the completion point in the argument list). An empty list requests
82  /// completion for the root matcher.
83  static std::vector<ArgKind> getAcceptedCompletionTypes(
84      llvm::ArrayRef<std::pair<MatcherCtor, unsigned>> Context);
85
86  /// Compute the list of completions that match any of
87  /// \p AcceptedTypes.
88  ///
89  /// \param AcceptedTypes All types accepted for this completion.
90  ///
91  /// \return All completions for the specified types.
92  /// Completions should be valid when used in \c lookupMatcherCtor().
93  /// The matcher constructed from the return of \c lookupMatcherCtor()
94  /// should be convertible to some type in \p AcceptedTypes.
95  static std::vector<MatcherCompletion>
96  getMatcherCompletions(ArrayRef<ArgKind> AcceptedTypes);
97
98  /// Construct a matcher from the registry.
99  ///
100  /// \param Ctor The matcher constructor to instantiate.
101  ///
102  /// \param NameRange The location of the name in the matcher source.
103  ///   Useful for error reporting.
104  ///
105  /// \param Args The argument list for the matcher. The number and types of the
106  ///   values must be valid for the matcher requested. Otherwise, the function
107  ///   will return an error.
108  ///
109  /// \return The matcher object constructed if no error was found.
110  ///   A null matcher if the number of arguments or argument types do not match
111  ///   the signature.  In that case \c Error will contain the description of
112  ///   the error.
113  static VariantMatcher constructMatcher(MatcherCtor Ctor,
114                                         SourceRange NameRange,
115                                         ArrayRef<ParserValue> Args,
116                                         Diagnostics *Error);
117
118  /// Construct a matcher from the registry and bind it.
119  ///
120  /// Similar the \c constructMatcher() above, but it then tries to bind the
121  /// matcher to the specified \c BindID.
122  /// If the matcher is not bindable, it sets an error in \c Error and returns
123  /// a null matcher.
124  static VariantMatcher constructBoundMatcher(MatcherCtor Ctor,
125                                              SourceRange NameRange,
126                                              StringRef BindID,
127                                              ArrayRef<ParserValue> Args,
128                                              Diagnostics *Error);
129};
130
131} // namespace dynamic
132} // namespace ast_matchers
133} // namespace clang
134
135#endif // LLVM_CLANG_AST_MATCHERS_DYNAMIC_REGISTRY_H
136