clang-tools 10.0.0

FindSymbols.cpp
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1 //===--- FindSymbols.cpp ------------------------------------*- 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 #include "FindSymbols.h"
9
10 #include "AST.h"
11 #include "FuzzyMatch.h"
12 #include "Logger.h"
13 #include "ParsedAST.h"
14 #include "Quality.h"
15 #include "SourceCode.h"
16 #include "index/Index.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/Index/IndexDataConsumer.h"
19 #include "clang/Index/IndexSymbol.h"
20 #include "clang/Index/IndexingAction.h"
21 #include "llvm/Support/FormatVariadic.h"
22 #include "llvm/Support/Path.h"
23 #include "llvm/Support/ScopedPrinter.h"
24
25 #define DEBUG_TYPE "FindSymbols"
26
27 namespace clang {
28 namespace clangd {
29
30 namespace {
31 using ScoredSymbolInfo = std::pair<float, SymbolInformation>;
32 struct ScoredSymbolGreater {
33 bool operator()(const ScoredSymbolInfo &L, const ScoredSymbolInfo &R) {
34 if (L.first != R.first)
35 return L.first > R.first;
36 return L.second.name < R.second.name; // Earlier name is better.
37 }
38 };
39
40 } // namespace
41
42 llvm::Expected<Location> symbolToLocation(const Symbol &Sym,
43 llvm::StringRef HintPath) {
44 // Prefer the definition over e.g. a function declaration in a header
45 auto &CD = Sym.Definition ? Sym.Definition : Sym.CanonicalDeclaration;
46 auto Path = URI::resolve(CD.FileURI, HintPath);
47 if (!Path) {
48 return llvm::make_error<llvm::StringError>(
49 formatv("Could not resolve path for symbol '{0}': {1}",
50 Sym.Name, llvm::toString(Path.takeError())),
51 llvm::inconvertibleErrorCode());
52 }
53 Location L;
54 // Use HintPath as TUPath since there is no TU associated with this
55 // request.
56 L.uri = URIForFile::canonicalize(*Path, HintPath);
57 Position Start, End;
58 Start.line = CD.Start.line();
59 Start.character = CD.Start.column();
60 End.line = CD.End.line();
61 End.character = CD.End.column();
62 L.range = {Start, End};
63 return L;
64 }
65
66 llvm::Expected<std::vector<SymbolInformation>>
67 getWorkspaceSymbols(llvm::StringRef Query, int Limit,
68 const SymbolIndex *const Index, llvm::StringRef HintPath) {
69 std::vector<SymbolInformation> Result;
70 if (Query.empty() || !Index)
71 return Result;
72
73 auto Names = splitQualifiedName(Query);
74
75 FuzzyFindRequest Req;
76 Req.Query = Names.second;
77
78 // FuzzyFind doesn't want leading :: qualifier
79 bool IsGlobalQuery = Names.first.consume_front("::");
80 // Restrict results to the scope in the query string if present (global or
81 // not).
82 if (IsGlobalQuery || !Names.first.empty())
83 Req.Scopes = {Names.first};
84 else
85 Req.AnyScope = true;
86 if (Limit)
87 Req.Limit = Limit;
88 TopN<ScoredSymbolInfo, ScoredSymbolGreater> Top(
89 Req.Limit ? *Req.Limit : std::numeric_limits<size_t>::max());
90 FuzzyMatcher Filter(Req.Query);
91 Index->fuzzyFind(Req, [HintPath, &Top, &Filter](const Symbol &Sym) {
92 auto Loc = symbolToLocation(Sym, HintPath);
93 if (!Loc) {
94 log("Workspace symbols: {0}", Loc.takeError());
95 return;
96 }
97
98 SymbolKind SK = indexSymbolKindToSymbolKind(Sym.SymInfo.Kind);
99 std::string Scope = Sym.Scope;
100 llvm::StringRef ScopeRef = Scope;
101 ScopeRef.consume_back("::");
102 SymbolInformation Info = {(Sym.Name + Sym.TemplateSpecializationArgs).str(),
103 SK, *Loc, ScopeRef};
104
105 SymbolQualitySignals Quality;
106 Quality.merge(Sym);
107 SymbolRelevanceSignals Relevance;
108 Relevance.Name = Sym.Name;
109 Relevance.Query = SymbolRelevanceSignals::Generic;
110 if (auto NameMatch = Filter.match(Sym.Name))
111 Relevance.NameMatch = *NameMatch;
112 else {
113 log("Workspace symbol: {0} didn't match query {1}", Sym.Name,
114 Filter.pattern());
115 return;
116 }
117 Relevance.merge(Sym);
118 auto Score =
119 evaluateSymbolAndRelevance(Quality.evaluate(), Relevance.evaluate());
120 dlog("FindSymbols: {0}{1} = {2}\n{3}{4}\n", Sym.Scope, Sym.Name, Score,
121 Quality, Relevance);
122
123 Top.push({Score, std::move(Info)});
124 });
125 for (auto &R : std::move(Top).items())
126 Result.push_back(std::move(R.second));
127 return Result;
128 }
129
130 namespace {
131 llvm::Optional<DocumentSymbol> declToSym(ASTContext &Ctx, const NamedDecl &ND) {
132 auto &SM = Ctx.getSourceManager();
133
134 SourceLocation NameLoc = nameLocation(ND, SM);
135 // getFileLoc is a good choice for us, but we also need to make sure
136 // sourceLocToPosition won't switch files, so we call getSpellingLoc on top of
137 // that to make sure it does not switch files.
138 // FIXME: sourceLocToPosition should not switch files!
139 SourceLocation BeginLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getBeginLoc()));
140 SourceLocation EndLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getEndLoc()));
141 if (NameLoc.isInvalid() || BeginLoc.isInvalid() || EndLoc.isInvalid())
142 return llvm::None;
143
144 if (!SM.isWrittenInMainFile(NameLoc) || !SM.isWrittenInMainFile(BeginLoc) ||
145 !SM.isWrittenInMainFile(EndLoc))
146 return llvm::None;
147
148 Position NameBegin = sourceLocToPosition(SM, NameLoc);
149 Position NameEnd = sourceLocToPosition(
150 SM, Lexer::getLocForEndOfToken(NameLoc, 0, SM, Ctx.getLangOpts()));
151
152 index::SymbolInfo SymInfo = index::getSymbolInfo(&ND);
153 // FIXME: this is not classifying constructors, destructors and operators
154 // correctly (they're all "methods").
155 SymbolKind SK = indexSymbolKindToSymbolKind(SymInfo.Kind);
156
157 DocumentSymbol SI;
158 SI.name = printName(Ctx, ND);
159 SI.kind = SK;
160 SI.deprecated = ND.isDeprecated();
161 SI.range =
162 Range{sourceLocToPosition(SM, BeginLoc), sourceLocToPosition(SM, EndLoc)};
163 SI.selectionRange = Range{NameBegin, NameEnd};
164 if (!SI.range.contains(SI.selectionRange)) {
165 // 'selectionRange' must be contained in 'range', so in cases where clang
166 // reports unrelated ranges we need to reconcile somehow.
167 SI.range = SI.selectionRange;
168 }
169 return SI;
170 }
171
172 /// A helper class to build an outline for the parse AST. It traverses the AST
173 /// directly instead of using RecursiveASTVisitor (RAV) for three main reasons:
174 /// - there is no way to keep RAV from traversing subtrees we are not
175 /// interested in. E.g. not traversing function locals or implicit template
176 /// instantiations.
177 /// - it's easier to combine results of recursive passes,
178 /// - visiting decls is actually simple, so we don't hit the complicated
179 /// cases that RAV mostly helps with (types, expressions, etc.)
180 class DocumentOutline {
181 public:
182 DocumentOutline(ParsedAST &AST) : AST(AST) {}
183
184 /// Builds the document outline for the generated AST.
185 std::vector<DocumentSymbol> build() {
186 std::vector<DocumentSymbol> Results;
187 for (auto &TopLevel : AST.getLocalTopLevelDecls())
188 traverseDecl(TopLevel, Results);
189 return Results;
190 }
191
192 private:
193 enum class VisitKind { No, OnlyDecl, DeclAndChildren };
194
195 void traverseDecl(Decl *D, std::vector<DocumentSymbol> &Results) {
196 if (auto *Templ = llvm::dyn_cast<TemplateDecl>(D))
197 D = Templ->getTemplatedDecl();
198 auto *ND = llvm::dyn_cast<NamedDecl>(D);
199 if (!ND)
200 return;
201 VisitKind Visit = shouldVisit(ND);
202 if (Visit == VisitKind::No)
203 return;
204 llvm::Optional<DocumentSymbol> Sym = declToSym(AST.getASTContext(), *ND);
205 if (!Sym)
206 return;
207 if (Visit == VisitKind::DeclAndChildren)
208 traverseChildren(D, Sym->children);
209 Results.push_back(std::move(*Sym));
210 }
211
212 void traverseChildren(Decl *D, std::vector<DocumentSymbol> &Results) {
213 auto *Scope = llvm::dyn_cast<DeclContext>(D);
214 if (!Scope)
215 return;
216 for (auto *C : Scope->decls())
217 traverseDecl(C, Results);
218 }
219
220 VisitKind shouldVisit(NamedDecl *D) {
221 if (D->isImplicit())
222 return VisitKind::No;
223
224 if (auto Func = llvm::dyn_cast<FunctionDecl>(D)) {
225 // Some functions are implicit template instantiations, those should be
226 // ignored.
227 if (auto *Info = Func->getTemplateSpecializationInfo()) {
228 if (!Info->isExplicitInstantiationOrSpecialization())
229 return VisitKind::No;
230 }
231 // Only visit the function itself, do not visit the children (i.e.
232 // function parameters, etc.)
233 return VisitKind::OnlyDecl;
234 }
235 // Handle template instantiations. We have three cases to consider:
236 // - explicit instantiations, e.g. 'template class std::vector<int>;'
237 // Visit the decl itself (it's present in the code), but not the
238 // children.
239 // - implicit instantiations, i.e. not written by the user.
240 // Do not visit at all, they are not present in the code.
241 // - explicit specialization, e.g. 'template <> class vector<bool> {};'
242 // Visit both the decl and its children, both are written in the code.
243 if (auto *TemplSpec = llvm::dyn_cast<ClassTemplateSpecializationDecl>(D)) {
244 if (TemplSpec->isExplicitInstantiationOrSpecialization())
245 return TemplSpec->isExplicitSpecialization()
246 ? VisitKind::DeclAndChildren
247 : VisitKind::OnlyDecl;
248 return VisitKind::No;
249 }
250 if (auto *TemplSpec = llvm::dyn_cast<VarTemplateSpecializationDecl>(D)) {
251 if (TemplSpec->isExplicitInstantiationOrSpecialization())
252 return TemplSpec->isExplicitSpecialization()
253 ? VisitKind::DeclAndChildren
254 : VisitKind::OnlyDecl;
255 return VisitKind::No;
256 }
257 // For all other cases, visit both the children and the decl.
258 return VisitKind::DeclAndChildren;
259 }
260
261 ParsedAST &AST;
262 };
263
264 std::vector<DocumentSymbol> collectDocSymbols(ParsedAST &AST) {
265 return DocumentOutline(AST).build();
266 }
267 } // namespace
268
269 llvm::Expected<std::vector<DocumentSymbol>> getDocumentSymbols(ParsedAST &AST) {
270 return collectDocSymbols(AST);
271 }
272
273 } // namespace clangd
274 } // namespace clang
Loc
SourceLocation Loc
&#39;#&#39; location in the include directive
Definition: IncludeOrderCheck.cpp:37
Limit
int Limit
Definition: FindSymbolsTests.cpp:71
clang::clangd::printName
std::string printName(const ASTContext &Ctx, const NamedDecl &ND)
Prints unqualified name of the decl for the purpose of displaying it to the user. ...
Definition: AST.cpp:208
Decl
const FunctionDecl * Decl
Definition: AvoidBindCheck.cpp:93
Quality
SignatureQualitySignals Quality
Definition: CodeComplete.cpp:796
AST.h
clang::clangd::getWorkspaceSymbols
llvm::Expected< std::vector< SymbolInformation > > getWorkspaceSymbols(llvm::StringRef Query, int Limit, const SymbolIndex *const Index, llvm::StringRef HintPath)
Searches for the symbols matching Query.
Definition: FindSymbols.cpp:67
clang::clangd::nameLocation
SourceLocation nameLocation(const clang::Decl &D, const SourceManager &SM)
Find the source location of the identifier for D.
Definition: AST.cpp:162
FindSymbols.h
clang::clangd::WantDiagnostics::No
Diagnostics must be generated for this snapshot.
Index.h
clang::clangd::SymbolIndex
Interface for symbol indexes that can be used for searching or matching symbols among a set of symbol...
Definition: Index.h:85
SourceCode.h
clang::clangd::splitQualifiedName
std::pair< StringRef, StringRef > splitQualifiedName(StringRef QName)
Definition: SourceCode.cpp:599
clang::clangd::indexSymbolKindToSymbolKind
SymbolKind indexSymbolKindToSymbolKind(index::SymbolKind Kind)
Definition: Protocol.cpp:216
clang::clangd::Position
Definition: Protocol.h:127
clang::clangd::Location::uri
URIForFile uri
The text document&#39;s URI.
Definition: Protocol.h:184
clang::tidy::cppcoreguidelines::toString
static llvm::StringRef toString(SpecialMemberFunctionsCheck::SpecialMemberFunctionKind K)
Definition: SpecialMemberFunctionsCheck.cpp:58
Results
std::vector< CodeCompletionResult > Results
Definition: CodeComplete.cpp:689
clang::clangd::FuzzyFindRequest
Definition: Index.h:26
clang::clangd::TextDocumentSyncKind::None
Documents should not be synced at all.
clang::clangd::FuzzyFindRequest::Scopes
std::vector< std::string > Scopes
If this is non-empty, symbols must be in at least one of the scopes (e.g.
Definition: Index.h:36
Score
llvm::Optional< float > Score
Definition: FuzzyMatchTests.cpp:48
clang::clangd::SymbolRelevanceSignals::Generic
Definition: Quality.h:124
clang::clangd::Symbol::Definition
SymbolLocation Definition
The location of the symbol&#39;s definition, if one was found.
Definition: Symbol.h:47
Ctx
Context Ctx
Definition: TUScheduler.cpp:237
clang::clangd::getSymbolInfo
std::vector< SymbolDetails > getSymbolInfo(ParsedAST &AST, Position Pos)
Get info about symbols at Pos.
Definition: XRefs.cpp:519
clang::clangd::SymbolOrigin::AST
SymbolInfo
clang::find_all_symbols::SymbolInfo SymbolInfo
Definition: FindAllSymbolsMain.cpp:38
clang::clangd::log
void log(const char *Fmt, Ts &&... Vals)
Definition: Logger.h:62
clang::clangd::Path
std::string Path
A typedef to represent a file path.
Definition: Path.h:20
clang::clangd::FuzzyFindRequest::Query
std::string Query
A query string for the fuzzy find.
Definition: Index.h:29
dlog
#define dlog(...)
Definition: Logger.h:72
clang::clangd::URIForFile::canonicalize
static URIForFile canonicalize(llvm::StringRef AbsPath, llvm::StringRef TUPath)
Canonicalizes AbsPath via URI.
Definition: Protocol.cpp:32
clang::find_all_symbols::SymbolInfo::SymbolKind
SymbolKind
The SymbolInfo Type.
Definition: SymbolInfo.h:30
clang::clangd::Symbol::CanonicalDeclaration
SymbolLocation CanonicalDeclaration
The location of the preferred declaration of the symbol.
Definition: Symbol.h:56
Quality.h
clang::clangd::symbolToLocation
llvm::Expected< Location > symbolToLocation(const Symbol &Sym, llvm::StringRef HintPath)
Helper function for deriving an LSP Location for a Symbol.
Definition: FindSymbols.cpp:42
clang::clangd::sourceLocToPosition
Position sourceLocToPosition(const SourceManager &SM, SourceLocation Loc)
Turn a SourceLocation into a [line, column] pair.
Definition: SourceCode.cpp:200
clang::clangd::MessageType::Info
An information message.
clang::clangd::ParsedAST
Stores and provides access to parsed AST.
Definition: ParsedAST.h:46
clang::clangd::evaluateSymbolAndRelevance
float evaluateSymbolAndRelevance(float SymbolQuality, float SymbolRelevance)
Combine symbol quality and relevance into a single score.
Definition: Quality.cpp:463
clang::clangd::Position::line
int line
Line position in a document (zero-based).
Definition: Protocol.h:129
Logger.h
clang::clangd::Position::character
int character
Character offset on a line in a document (zero-based).
Definition: Protocol.h:134
clang::clangd::Symbol
The class presents a C++ symbol, e.g.
Definition: Symbol.h:36
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27
ParsedAST.h
clang::clangd::Symbol::Name
llvm::StringRef Name
The unqualified name of the symbol, e.g. "bar" (for ns::bar).
Definition: Symbol.h:42
clang::clangd::getDocumentSymbols
llvm::Expected< std::vector< DocumentSymbol > > getDocumentSymbols(ParsedAST &AST)
Retrieves the symbols contained in the "main file" section of an AST in the same order that they appe...
Definition: FindSymbols.cpp:269
Range
CharSourceRange Range
SourceRange for the file name.
Definition: IncludeOrderCheck.cpp:38
clang::clangd::URI::resolve
static llvm::Expected< std::string > resolve(const URI &U, llvm::StringRef HintPath="")
Resolves the absolute path of U.
Definition: URI.cpp:233
FuzzyMatch.h
clang::clangd::Location
Definition: Protocol.h:182
Index
const SymbolIndex * Index
Definition: Dexp.cpp:84