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

66 lines
2.1 KiB
C++

//===--- SemanticSelection.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 "SemanticSelection.h"
#include "ParsedAST.h"
#include "Protocol.h"
#include "Selection.h"
#include "SourceCode.h"
#include "clang/AST/DeclBase.h"
#include "clang/Basic/SourceLocation.h"
#include "llvm/Support/Error.h"
namespace clang {
namespace clangd {
namespace {
// Adds Range \p R to the Result if it is distinct from the last added Range.
// Assumes that only consecutive ranges can coincide.
void addIfDistinct(const Range &R, std::vector<Range> &Result) {
if (Result.empty() || Result.back() != R) {
Result.push_back(R);
}
}
} // namespace
llvm::Expected<std::vector<Range>> getSemanticRanges(ParsedAST &AST,
Position Pos) {
std::vector<Range> Result;
const auto &SM = AST.getSourceManager();
const auto &LangOpts = AST.getLangOpts();
auto FID = SM.getMainFileID();
auto Offset = positionToOffset(SM.getBufferData(FID), Pos);
if (!Offset) {
return Offset.takeError();
}
// Get node under the cursor.
SelectionTree ST = SelectionTree::createRight(
AST.getASTContext(), AST.getTokens(), *Offset, *Offset);
for (const auto *Node = ST.commonAncestor(); Node != nullptr;
Node = Node->Parent) {
if (const Decl *D = Node->ASTNode.get<Decl>()) {
if (llvm::isa<TranslationUnitDecl>(D)) {
break;
}
}
auto SR = toHalfOpenFileRange(SM, LangOpts, Node->ASTNode.getSourceRange());
if (!SR.hasValue() || SM.getFileID(SR->getBegin()) != SM.getMainFileID()) {
continue;
}
Range R;
R.start = sourceLocToPosition(SM, SR->getBegin());
R.end = sourceLocToPosition(SM, SR->getEnd());
addIfDistinct(R, Result);
}
return Result;
}
} // namespace clangd
} // namespace clang