llvm-project/clang-tools-extra/clangd/FindSymbols.cpp

270 lines
9.5 KiB
C++
Raw Normal View History

//===--- FindSymbols.cpp ------------------------------------*- C++-*------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "FindSymbols.h"
#include "AST.h"
#include "ClangdUnit.h"
#include "FuzzyMatch.h"
#include "Logger.h"
#include "Quality.h"
#include "SourceCode.h"
#include "index/Index.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/Index/IndexDataConsumer.h"
#include "clang/Index/IndexSymbol.h"
#include "clang/Index/IndexingAction.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/ScopedPrinter.h"
#define DEBUG_TYPE "FindSymbols"
namespace clang {
namespace clangd {
namespace {
using ScoredSymbolInfo = std::pair<float, SymbolInformation>;
struct ScoredSymbolGreater {
bool operator()(const ScoredSymbolInfo &L, const ScoredSymbolInfo &R) {
if (L.first != R.first)
return L.first > R.first;
return L.second.name < R.second.name; // Earlier name is better.
}
};
} // namespace
llvm::Expected<std::vector<SymbolInformation>>
getWorkspaceSymbols(llvm::StringRef Query, int Limit,
const SymbolIndex *const Index, llvm::StringRef HintPath) {
std::vector<SymbolInformation> Result;
if (Query.empty() || !Index)
return Result;
auto Names = splitQualifiedName(Query);
FuzzyFindRequest Req;
Req.Query = Names.second;
// FuzzyFind doesn't want leading :: qualifier
bool IsGlobalQuery = Names.first.consume_front("::");
// Restrict results to the scope in the query string if present (global or
// not).
if (IsGlobalQuery || !Names.first.empty())
Req.Scopes = {Names.first};
else
Req.AnyScope = true;
if (Limit)
Req.Limit = Limit;
TopN<ScoredSymbolInfo, ScoredSymbolGreater> Top(
Req.Limit ? *Req.Limit : std::numeric_limits<size_t>::max());
FuzzyMatcher Filter(Req.Query);
Index->fuzzyFind(Req, [HintPath, &Top, &Filter](const Symbol &Sym) {
// Prefer the definition over e.g. a function declaration in a header
auto &CD = Sym.Definition ? Sym.Definition : Sym.CanonicalDeclaration;
auto Uri = URI::parse(CD.FileURI);
if (!Uri) {
log("Workspace symbol: Could not parse URI '{0}' for symbol '{1}'.",
CD.FileURI, Sym.Name);
return;
}
auto Path = URI::resolve(*Uri, HintPath);
if (!Path) {
log("Workspace symbol: Could not resolve path for URI '{0}' for symbol "
"'{1}'.",
Uri->toString(), Sym.Name);
return;
}
Location L;
// Use HintPath as TUPath since there is no TU associated with this
// request.
L.uri = URIForFile::canonicalize(*Path, HintPath);
Position Start, End;
Start.line = CD.Start.line();
Start.character = CD.Start.column();
End.line = CD.End.line();
End.character = CD.End.column();
L.range = {Start, End};
SymbolKind SK = indexSymbolKindToSymbolKind(Sym.SymInfo.Kind);
std::string Scope = Sym.Scope;
llvm::StringRef ScopeRef = Scope;
ScopeRef.consume_back("::");
SymbolInformation Info = {(Sym.Name + Sym.TemplateSpecializationArgs).str(),
SK, L, ScopeRef};
SymbolQualitySignals Quality;
Quality.merge(Sym);
SymbolRelevanceSignals Relevance;
Relevance.Name = Sym.Name;
Relevance.Query = SymbolRelevanceSignals::Generic;
if (auto NameMatch = Filter.match(Sym.Name))
Relevance.NameMatch = *NameMatch;
else {
log("Workspace symbol: {0} didn't match query {1}", Sym.Name,
Filter.pattern());
return;
}
Relevance.merge(Sym);
auto Score =
evaluateSymbolAndRelevance(Quality.evaluate(), Relevance.evaluate());
dlog("FindSymbols: {0}{1} = {2}\n{3}{4}\n", Sym.Scope, Sym.Name, Score,
Quality, Relevance);
Top.push({Score, std::move(Info)});
});
for (auto &R : std::move(Top).items())
Result.push_back(std::move(R.second));
return Result;
}
namespace {
llvm::Optional<DocumentSymbol> declToSym(ASTContext &Ctx, const NamedDecl &ND) {
auto &SM = Ctx.getSourceManager();
SourceLocation NameLoc = findNameLoc(&ND);
// getFileLoc is a good choice for us, but we also need to make sure
// sourceLocToPosition won't switch files, so we call getSpellingLoc on top of
// that to make sure it does not switch files.
// FIXME: sourceLocToPosition should not switch files!
SourceLocation BeginLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getBeginLoc()));
SourceLocation EndLoc = SM.getSpellingLoc(SM.getFileLoc(ND.getEndLoc()));
if (NameLoc.isInvalid() || BeginLoc.isInvalid() || EndLoc.isInvalid())
return llvm::None;
if (!SM.isWrittenInMainFile(NameLoc) || !SM.isWrittenInMainFile(BeginLoc) ||
!SM.isWrittenInMainFile(EndLoc))
return llvm::None;
Position NameBegin = sourceLocToPosition(SM, NameLoc);
Position NameEnd = sourceLocToPosition(
SM, Lexer::getLocForEndOfToken(NameLoc, 0, SM, Ctx.getLangOpts()));
index::SymbolInfo SymInfo = index::getSymbolInfo(&ND);
// FIXME: this is not classifying constructors, destructors and operators
// correctly (they're all "methods").
SymbolKind SK = indexSymbolKindToSymbolKind(SymInfo.Kind);
DocumentSymbol SI;
SI.name = printName(Ctx, ND);
SI.kind = SK;
SI.deprecated = ND.isDeprecated();
SI.range =
Range{sourceLocToPosition(SM, BeginLoc), sourceLocToPosition(SM, EndLoc)};
SI.selectionRange = Range{NameBegin, NameEnd};
if (!SI.range.contains(SI.selectionRange)) {
// 'selectionRange' must be contained in 'range', so in cases where clang
// reports unrelated ranges we need to reconcile somehow.
SI.range = SI.selectionRange;
}
return SI;
}
/// A helper class to build an outline for the parse AST. It traverse the AST
/// directly instead of using RecursiveASTVisitor (RAV) for three main reasons:
/// - there is no way to keep RAV from traversing subtrees we're not
/// interested in. E.g. not traversing function locals or implicit template
/// instantiations.
/// - it's easier to combine results of recursive passes, e.g.
/// - visiting decls is actually simple, so we don't hit the complicated
/// cases that RAV mostly helps with (types and expressions, etc.)
class DocumentOutline {
public:
DocumentOutline(ParsedAST &AST) : AST(AST) {}
/// Builds the document outline for the generated AST.
std::vector<DocumentSymbol> build() {
std::vector<DocumentSymbol> Results;
for (auto &TopLevel : AST.getLocalTopLevelDecls())
traverseDecl(TopLevel, Results);
return Results;
}
private:
enum class VisitKind { No, OnlyDecl, DeclAndChildren };
void traverseDecl(Decl *D, std::vector<DocumentSymbol> &Results) {
if (auto *Templ = llvm::dyn_cast<TemplateDecl>(D))
D = Templ->getTemplatedDecl();
auto *ND = llvm::dyn_cast<NamedDecl>(D);
if (!ND)
return;
VisitKind Visit = shouldVisit(ND);
if (Visit == VisitKind::No)
return;
llvm::Optional<DocumentSymbol> Sym = declToSym(AST.getASTContext(), *ND);
if (!Sym)
return;
if (Visit == VisitKind::DeclAndChildren)
traverseChildren(D, Sym->children);
Results.push_back(std::move(*Sym));
}
void traverseChildren(Decl *D, std::vector<DocumentSymbol> &Results) {
auto *Scope = llvm::dyn_cast<DeclContext>(D);
if (!Scope)
return;
for (auto *C : Scope->decls())
traverseDecl(C, Results);
}
VisitKind shouldVisit(NamedDecl *D) {
if (D->isImplicit())
return VisitKind::No;
if (auto Func = llvm::dyn_cast<FunctionDecl>(D)) {
// Some functions are implicit template instantiations, those should be
// ignored.
if (auto *Info = Func->getTemplateSpecializationInfo()) {
if (!Info->isExplicitInstantiationOrSpecialization())
return VisitKind::No;
}
// Only visit the function itself, do not visit the children (i.e.
// function parameters, etc.)
return VisitKind::OnlyDecl;
}
// Handle template instantiations. We have three cases to consider:
// - explicit instantiations, e.g. 'template class std::vector<int>;'
// Visit the decl itself (it's present in the code), but not the
// children.
// - implicit instantiations, i.e. not written by the user.
// Do not visit at all, they are not present in the code.
// - explicit specialization, e.g. 'template <> class vector<bool> {};'
// Visit both the decl and its children, both are written in the code.
if (auto *TemplSpec = llvm::dyn_cast<ClassTemplateSpecializationDecl>(D)) {
if (TemplSpec->isExplicitInstantiationOrSpecialization())
return TemplSpec->isExplicitSpecialization()
? VisitKind::DeclAndChildren
: VisitKind::OnlyDecl;
return VisitKind::No;
}
if (auto *TemplSpec = llvm::dyn_cast<VarTemplateSpecializationDecl>(D)) {
if (TemplSpec->isExplicitInstantiationOrSpecialization())
return TemplSpec->isExplicitSpecialization()
? VisitKind::DeclAndChildren
: VisitKind::OnlyDecl;
return VisitKind::No;
}
// For all other cases, visit both the children and the decl.
return VisitKind::DeclAndChildren;
}
ParsedAST &AST;
};
std::vector<DocumentSymbol> collectDocSymbols(ParsedAST &AST) {
return DocumentOutline(AST).build();
}
} // namespace
llvm::Expected<std::vector<DocumentSymbol>> getDocumentSymbols(ParsedAST &AST) {
return collectDocSymbols(AST);
}
} // namespace clangd
} // namespace clang