clang-tools  8.0.0
DraftStore.cpp
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1 //===--- DraftStore.cpp - File contents container ---------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "DraftStore.h"
11 #include "SourceCode.h"
12 #include "llvm/Support/Errc.h"
13 
14 namespace clang {
15 namespace clangd {
16 
17 llvm::Optional<std::string> DraftStore::getDraft(PathRef File) const {
18  std::lock_guard<std::mutex> Lock(Mutex);
19 
20  auto It = Drafts.find(File);
21  if (It == Drafts.end())
22  return None;
23 
24  return It->second;
25 }
26 
27 std::vector<Path> DraftStore::getActiveFiles() const {
28  std::lock_guard<std::mutex> Lock(Mutex);
29  std::vector<Path> ResultVector;
30 
31  for (auto DraftIt = Drafts.begin(); DraftIt != Drafts.end(); DraftIt++)
32  ResultVector.push_back(DraftIt->getKey());
33 
34  return ResultVector;
35 }
36 
37 void DraftStore::addDraft(PathRef File, llvm::StringRef Contents) {
38  std::lock_guard<std::mutex> Lock(Mutex);
39 
40  Drafts[File] = Contents;
41 }
42 
43 llvm::Expected<std::string> DraftStore::updateDraft(
44  PathRef File, llvm::ArrayRef<TextDocumentContentChangeEvent> Changes) {
45  std::lock_guard<std::mutex> Lock(Mutex);
46 
47  auto EntryIt = Drafts.find(File);
48  if (EntryIt == Drafts.end()) {
49  return llvm::make_error<llvm::StringError>(
50  "Trying to do incremental update on non-added document: " + File,
51  llvm::errc::invalid_argument);
52  }
53 
54  std::string Contents = EntryIt->second;
55 
56  for (const TextDocumentContentChangeEvent &Change : Changes) {
57  if (!Change.range) {
58  Contents = Change.text;
59  continue;
60  }
61 
62  const Position &Start = Change.range->start;
63  llvm::Expected<size_t> StartIndex =
64  positionToOffset(Contents, Start, false);
65  if (!StartIndex)
66  return StartIndex.takeError();
67 
68  const Position &End = Change.range->end;
69  llvm::Expected<size_t> EndIndex = positionToOffset(Contents, End, false);
70  if (!EndIndex)
71  return EndIndex.takeError();
72 
73  if (*EndIndex < *StartIndex)
74  return llvm::make_error<llvm::StringError>(
75  llvm::formatv(
76  "Range's end position ({0}) is before start position ({1})", End,
77  Start),
78  llvm::errc::invalid_argument);
79 
80  // Since the range length between two LSP positions is dependent on the
81  // contents of the buffer we compute the range length between the start and
82  // end position ourselves and compare it to the range length of the LSP
83  // message to verify the buffers of the client and server are in sync.
84 
85  // EndIndex and StartIndex are in bytes, but Change.rangeLength is in UTF-16
86  // code units.
87  ssize_t ComputedRangeLength =
88  lspLength(Contents.substr(*StartIndex, *EndIndex - *StartIndex));
89 
90  if (Change.rangeLength && ComputedRangeLength != *Change.rangeLength)
91  return llvm::make_error<llvm::StringError>(
92  llvm::formatv("Change's rangeLength ({0}) doesn't match the "
93  "computed range length ({1}).",
94  *Change.rangeLength, *EndIndex - *StartIndex),
95  llvm::errc::invalid_argument);
96 
97  std::string NewContents;
98  NewContents.reserve(*StartIndex + Change.text.length() +
99  (Contents.length() - *EndIndex));
100 
101  NewContents = Contents.substr(0, *StartIndex);
102  NewContents += Change.text;
103  NewContents += Contents.substr(*EndIndex);
104 
105  Contents = std::move(NewContents);
106  }
107 
108  EntryIt->second = Contents;
109  return Contents;
110 }
111 
113  std::lock_guard<std::mutex> Lock(Mutex);
114 
115  Drafts.erase(File);
116 }
117 
118 } // namespace clangd
119 } // namespace clang
llvm::StringRef Contents
size_t lspLength(llvm::StringRef Code)
Definition: SourceCode.cpp:70
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:24
void addDraft(PathRef File, StringRef Contents)
Replace contents of the draft for File with Contents.
Definition: DraftStore.cpp:37
Documents should not be synced at all.
llvm::Expected< std::string > updateDraft(PathRef File, llvm::ArrayRef< TextDocumentContentChangeEvent > Changes)
Update the contents of the draft for File based on Changes.
Definition: DraftStore.cpp:43
llvm::Expected< size_t > positionToOffset(llvm::StringRef Code, Position P, bool AllowColumnsBeyondLineLength)
Turn a [line, column] pair into an offset in Code.
Definition: SourceCode.cpp:81
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
std::vector< Path > getActiveFiles() const
Definition: DraftStore.cpp:27
void removeDraft(PathRef File)
Remove the draft from the store.
Definition: DraftStore.cpp:112
llvm::Optional< std::string > getDraft(PathRef File) const
Definition: DraftStore.cpp:17