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

139 lines
4.4 KiB
C++

//===--- DraftStore.cpp - File contents container ---------------*- 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 "DraftStore.h"
#include "SourceCode.h"
#include "support/Logger.h"
#include "llvm/Support/Errc.h"
namespace clang {
namespace clangd {
llvm::Optional<DraftStore::Draft> DraftStore::getDraft(PathRef File) const {
std::lock_guard<std::mutex> Lock(Mutex);
auto It = Drafts.find(File);
if (It == Drafts.end())
return None;
return It->second;
}
std::vector<Path> DraftStore::getActiveFiles() const {
std::lock_guard<std::mutex> Lock(Mutex);
std::vector<Path> ResultVector;
for (auto DraftIt = Drafts.begin(); DraftIt != Drafts.end(); DraftIt++)
ResultVector.push_back(std::string(DraftIt->getKey()));
return ResultVector;
}
static void updateVersion(DraftStore::Draft &D,
llvm::Optional<int64_t> Version) {
if (Version) {
// We treat versions as opaque, but the protocol says they increase.
if (*Version <= D.Version)
log("File version went from {0} to {1}", D.Version, Version);
D.Version = *Version;
} else {
// Note that if D was newly-created, this will bump D.Version from -1 to 0.
++D.Version;
}
}
int64_t DraftStore::addDraft(PathRef File, llvm::Optional<int64_t> Version,
llvm::StringRef Contents) {
std::lock_guard<std::mutex> Lock(Mutex);
Draft &D = Drafts[File];
updateVersion(D, Version);
D.Contents = Contents.str();
return D.Version;
}
llvm::Expected<DraftStore::Draft> DraftStore::updateDraft(
PathRef File, llvm::Optional<int64_t> Version,
llvm::ArrayRef<TextDocumentContentChangeEvent> Changes) {
std::lock_guard<std::mutex> Lock(Mutex);
auto EntryIt = Drafts.find(File);
if (EntryIt == Drafts.end()) {
return llvm::make_error<llvm::StringError>(
"Trying to do incremental update on non-added document: " + File,
llvm::errc::invalid_argument);
}
Draft &D = EntryIt->second;
std::string Contents = EntryIt->second.Contents;
for (const TextDocumentContentChangeEvent &Change : Changes) {
if (!Change.range) {
Contents = Change.text;
continue;
}
const Position &Start = Change.range->start;
llvm::Expected<size_t> StartIndex =
positionToOffset(Contents, Start, false);
if (!StartIndex)
return StartIndex.takeError();
const Position &End = Change.range->end;
llvm::Expected<size_t> EndIndex = positionToOffset(Contents, End, false);
if (!EndIndex)
return EndIndex.takeError();
if (*EndIndex < *StartIndex)
return llvm::make_error<llvm::StringError>(
llvm::formatv(
"Range's end position ({0}) is before start position ({1})", End,
Start),
llvm::errc::invalid_argument);
// Since the range length between two LSP positions is dependent on the
// contents of the buffer we compute the range length between the start and
// end position ourselves and compare it to the range length of the LSP
// message to verify the buffers of the client and server are in sync.
// EndIndex and StartIndex are in bytes, but Change.rangeLength is in UTF-16
// code units.
ssize_t ComputedRangeLength =
lspLength(Contents.substr(*StartIndex, *EndIndex - *StartIndex));
if (Change.rangeLength && ComputedRangeLength != *Change.rangeLength)
return llvm::make_error<llvm::StringError>(
llvm::formatv("Change's rangeLength ({0}) doesn't match the "
"computed range length ({1}).",
*Change.rangeLength, ComputedRangeLength),
llvm::errc::invalid_argument);
std::string NewContents;
NewContents.reserve(*StartIndex + Change.text.length() +
(Contents.length() - *EndIndex));
NewContents = Contents.substr(0, *StartIndex);
NewContents += Change.text;
NewContents += Contents.substr(*EndIndex);
Contents = std::move(NewContents);
}
updateVersion(D, Version);
D.Contents = std::move(Contents);
return D;
}
void DraftStore::removeDraft(PathRef File) {
std::lock_guard<std::mutex> Lock(Mutex);
Drafts.erase(File);
}
} // namespace clangd
} // namespace clang