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

81 lines
2.8 KiB
C++

//===--- SourceCode.h - Manipulating source code as strings -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "SourceCode.h"
#include "clang/Basic/SourceManager.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Error.h"
namespace clang {
namespace clangd {
using namespace llvm;
llvm::Expected<size_t> positionToOffset(StringRef Code, Position P,
bool AllowColumnsBeyondLineLength) {
if (P.line < 0)
return llvm::make_error<llvm::StringError>(
llvm::formatv("Line value can't be negative ({0})", P.line),
llvm::errc::invalid_argument);
if (P.character < 0)
return llvm::make_error<llvm::StringError>(
llvm::formatv("Character value can't be negative ({0})", P.character),
llvm::errc::invalid_argument);
size_t StartOfLine = 0;
for (int I = 0; I != P.line; ++I) {
size_t NextNL = Code.find('\n', StartOfLine);
if (NextNL == StringRef::npos)
return llvm::make_error<llvm::StringError>(
llvm::formatv("Line value is out of range ({0})", P.line),
llvm::errc::invalid_argument);
StartOfLine = NextNL + 1;
}
size_t NextNL = Code.find('\n', StartOfLine);
if (NextNL == StringRef::npos)
NextNL = Code.size();
if (StartOfLine + P.character > NextNL && !AllowColumnsBeyondLineLength)
return llvm::make_error<llvm::StringError>(
llvm::formatv("Character value is out of range ({0})", P.character),
llvm::errc::invalid_argument);
// FIXME: officially P.character counts UTF-16 code units, not UTF-8 bytes!
return std::min(NextNL, StartOfLine + P.character);
}
Position offsetToPosition(StringRef Code, size_t Offset) {
Offset = std::min(Code.size(), Offset);
StringRef Before = Code.substr(0, Offset);
int Lines = Before.count('\n');
size_t PrevNL = Before.rfind('\n');
size_t StartOfLine = (PrevNL == StringRef::npos) ? 0 : (PrevNL + 1);
// FIXME: officially character counts UTF-16 code units, not UTF-8 bytes!
Position Pos;
Pos.line = Lines;
Pos.character = static_cast<int>(Offset - StartOfLine);
return Pos;
}
Position sourceLocToPosition(const SourceManager &SM, SourceLocation Loc) {
Position P;
P.line = static_cast<int>(SM.getSpellingLineNumber(Loc)) - 1;
P.character = static_cast<int>(SM.getSpellingColumnNumber(Loc)) - 1;
return P;
}
Range halfOpenToRange(const SourceManager &SM, CharSourceRange R) {
// Clang is 1-based, LSP uses 0-based indexes.
Position Begin = sourceLocToPosition(SM, R.getBegin());
Position End = sourceLocToPosition(SM, R.getEnd());
return {Begin, End};
}
} // namespace clangd
} // namespace clang