xref: /llvm-project/clang-tools-extra/clangd/XRefs.h (revision 61fe67a4017375fd675f75652e857e837f77fa51)
1 //===--- XRefs.h -------------------------------------------------*- 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 // Features that traverse references between symbols.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_XREFS_H
14 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_XREFS_H
15 
16 #include "Protocol.h"
17 #include "SourceCode.h"
18 #include "index/Index.h"
19 #include "index/SymbolID.h"
20 #include "support/Path.h"
21 #include "clang/AST/ASTTypeTraits.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/Support/raw_ostream.h"
24 #include <optional>
25 #include <vector>
26 
27 namespace clang {
28 namespace syntax {
29 class Token;
30 class TokenBuffer;
31 } // namespace syntax
32 namespace clangd {
33 class ParsedAST;
34 
35 // Describes where a symbol is declared and defined (as far as clangd knows).
36 // There are three cases:
37 //  - a declaration only, no definition is known (e.g. only header seen)
38 //  - a declaration and a distinct definition (e.g. function declared in header)
39 //  - a declaration and an equal definition (e.g. inline function, or class)
40 // For some types of symbol, e.g. macros, definition == declaration always.
41 struct LocatedSymbol {
42   // The (unqualified) name of the symbol.
43   std::string Name;
44   // The canonical or best declaration: where most users find its interface.
45   Location PreferredDeclaration;
46   // Where the symbol is defined, if known. May equal PreferredDeclaration.
47   std::optional<Location> Definition;
48   // SymbolID of the located symbol if available.
49   SymbolID ID;
50 };
51 llvm::raw_ostream &operator<<(llvm::raw_ostream &, const LocatedSymbol &);
52 /// Get definition of symbol at a specified \p Pos.
53 /// Multiple locations may be returned, corresponding to distinct symbols.
54 std::vector<LocatedSymbol> locateSymbolAt(ParsedAST &AST, Position Pos,
55                                           const SymbolIndex *Index = nullptr);
56 
57 // Tries to provide a textual fallback for locating a symbol by looking up the
58 // word under the cursor as a symbol name in the index.
59 // The aim is to pick up references to symbols in contexts where
60 // AST-based resolution does not work, such as comments, strings, and PP
61 // disabled regions.
62 // (This is for internal use by locateSymbolAt, and is exposed for testing).
63 std::vector<LocatedSymbol> locateSymbolTextually(const SpelledWord &Word,
64                                                  ParsedAST &AST,
65                                                  const SymbolIndex *Index,
66                                                  llvm::StringRef MainFilePath,
67                                                  ASTNodeKind NodeKind);
68 
69 // Try to find a proximate occurrence of `Word` as an identifier, which can be
70 // used to resolve it.
71 // (This is for internal use by locateSymbolAt, and is exposed for testing).
72 const syntax::Token *findNearbyIdentifier(const SpelledWord &Word,
73                                           const syntax::TokenBuffer &TB);
74 
75 /// Get all document links
76 std::vector<DocumentLink> getDocumentLinks(ParsedAST &AST);
77 
78 /// Returns highlights for all usages of a symbol at \p Pos.
79 std::vector<DocumentHighlight> findDocumentHighlights(ParsedAST &AST,
80                                                       Position Pos);
81 
82 struct ReferencesResult {
83   // Bitmask describing whether the occurrence is a declaration, definition etc.
84   enum ReferenceAttributes : unsigned {
85     Declaration = 1 << 0,
86     Definition = 1 << 1,
87     // The occurrence is an override of the target base method.
88     Override = 1 << 2,
89   };
90   struct Reference {
91     ReferenceLocation Loc;
92     unsigned Attributes = 0;
93   };
94   std::vector<Reference> References;
95   bool HasMore = false;
96 };
97 llvm::raw_ostream &operator<<(llvm::raw_ostream &,
98                               const ReferencesResult::Reference &);
99 
100 /// Returns implementations at a specified \p Pos:
101 ///   - overrides for a virtual method;
102 ///   - subclasses for a base class;
103 std::vector<LocatedSymbol> findImplementations(ParsedAST &AST, Position Pos,
104                                                const SymbolIndex *Index);
105 
106 /// Returns symbols for types referenced at \p Pos.
107 ///
108 /// For example, given `b^ar()` wher bar return Foo, this function returns the
109 /// definition of class Foo.
110 std::vector<LocatedSymbol> findType(ParsedAST &AST, Position Pos,
111                                     const SymbolIndex *Index);
112 
113 /// Returns references of the symbol at a specified \p Pos.
114 /// \p Limit limits the number of results returned (0 means no limit).
115 ReferencesResult findReferences(ParsedAST &AST, Position Pos, uint32_t Limit,
116                                 const SymbolIndex *Index = nullptr,
117                                 bool AddContext = false);
118 
119 /// Get info about symbols at \p Pos.
120 std::vector<SymbolDetails> getSymbolInfo(ParsedAST &AST, Position Pos);
121 
122 /// Find the record types referenced at \p Pos.
123 std::vector<const CXXRecordDecl *> findRecordTypeAt(ParsedAST &AST,
124                                                     Position Pos);
125 
126 /// Given a record type declaration, find its base (parent) types.
127 std::vector<const CXXRecordDecl *> typeParents(const CXXRecordDecl *CXXRD);
128 
129 /// Get type hierarchy information at \p Pos.
130 std::vector<TypeHierarchyItem> getTypeHierarchy(
131     ParsedAST &AST, Position Pos, int Resolve, TypeHierarchyDirection Direction,
132     const SymbolIndex *Index = nullptr, PathRef TUPath = PathRef{});
133 
134 /// Returns direct parents of a TypeHierarchyItem using SymbolIDs stored inside
135 /// the item.
136 std::optional<std::vector<TypeHierarchyItem>>
137 superTypes(const TypeHierarchyItem &Item, const SymbolIndex *Index);
138 /// Returns direct children of a TypeHierarchyItem.
139 std::vector<TypeHierarchyItem> subTypes(const TypeHierarchyItem &Item,
140                                         const SymbolIndex *Index);
141 
142 void resolveTypeHierarchy(TypeHierarchyItem &Item, int ResolveLevels,
143                           TypeHierarchyDirection Direction,
144                           const SymbolIndex *Index);
145 
146 /// Get call hierarchy information at \p Pos.
147 std::vector<CallHierarchyItem>
148 prepareCallHierarchy(ParsedAST &AST, Position Pos, PathRef TUPath);
149 
150 std::vector<CallHierarchyIncomingCall>
151 incomingCalls(const CallHierarchyItem &Item, const SymbolIndex *Index);
152 
153 std::vector<CallHierarchyOutgoingCall>
154 outgoingCalls(const CallHierarchyItem &Item, const SymbolIndex *Index);
155 
156 /// Returns all decls that are referenced in the \p FD except local symbols.
157 llvm::DenseSet<const Decl *> getNonLocalDeclRefs(ParsedAST &AST,
158                                                  const FunctionDecl *FD);
159 } // namespace clangd
160 } // namespace clang
161 
162 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_XREFS_H
163