Index: clangd/ClangdLSPServer.h
===================================================================
--- clangd/ClangdLSPServer.h
+++ clangd/ClangdLSPServer.h
@@ -86,12 +86,6 @@
   /// It's used to break out of the LSP parsing loop.
   bool IsDone = false;
 
-  std::mutex FixItsMutex;
-  typedef std::map<clangd::Diagnostic, std::vector<clang::tooling::Replacement>>
-      DiagnosticToReplacementMap;
-  /// Caches FixIts per file and diagnostics
-  llvm::StringMap<DiagnosticToReplacementMap> FixItsMap;
-
   // Various ClangdServer parameters go here. It's important they're created
   // before ClangdServer.
   DirectoryBasedGlobalCompilationDatabase CDB;
Index: clangd/ClangdLSPServer.cpp
===================================================================
--- clangd/ClangdLSPServer.cpp
+++ clangd/ClangdLSPServer.cpp
@@ -15,25 +15,6 @@
 using namespace clang::clangd;
 using namespace clang;
 
-namespace {
-
-std::vector<TextEdit>
-replacementsToEdits(StringRef Code,
-                    const std::vector<tooling::Replacement> &Replacements) {
-  // Turn the replacements into the format specified by the Language Server
-  // Protocol. Fuse them into one big JSON array.
-  std::vector<TextEdit> Edits;
-  for (auto &R : Replacements) {
-    Range ReplacementRange = {
-        offsetToPosition(Code, R.getOffset()),
-        offsetToPosition(Code, R.getOffset() + R.getLength())};
-    Edits.push_back({ReplacementRange, R.getReplacementText()});
-  }
-  return Edits;
-}
-
-} // namespace
-
 void ClangdLSPServer::onInitialize(Ctx C, InitializeParams &Params) {
   C.reply(json::obj{
       {{"capabilities",
@@ -130,16 +111,13 @@
 
 void ClangdLSPServer::onRename(Ctx C, RenameParams &Params) {
   auto File = Params.textDocument.uri.file;
-  auto Replacements = Server.rename(File, Params.position, Params.newName);
-  if (!Replacements) {
-    C.replyError(ErrorCode::InternalError,
-                 llvm::toString(Replacements.takeError()));
+  auto Edits = Server.rename(File, Params.position, Params.newName);
+  if (!Edits) {
+    C.replyError(ErrorCode::InternalError, llvm::toString(Edits.takeError()));
     return;
   }
-  std::string Code = Server.getDocument(File);
-  std::vector<TextEdit> Edits = replacementsToEdits(Code, *Replacements);
   WorkspaceEdit WE;
-  WE.changes = {{llvm::yaml::escape(Params.textDocument.uri.uri), Edits}};
+  WE.changes = {{llvm::yaml::escape(Params.textDocument.uri.uri), *Edits}};
   C.reply(WorkspaceEdit::unparse(WE));
 }
 
@@ -150,41 +128,48 @@
 
 void ClangdLSPServer::onDocumentOnTypeFormatting(
     Ctx C, DocumentOnTypeFormattingParams &Params) {
-  auto File = Params.textDocument.uri.file;
-  std::string Code = Server.getDocument(File);
-  C.reply(json::ary(
-      replacementsToEdits(Code, Server.formatOnType(File, Params.position))));
+  const PathRef File = Params.textDocument.uri.file;
+  auto EditsOrError = Server.formatOnType(File, Params.position);
+  if (EditsOrError)
+    C.reply(json::ary{EditsOrError.get()});
+  else
+    C.replyError(EditsOrError.takeError());
 }
 
 void ClangdLSPServer::onDocumentRangeFormatting(
     Ctx C, DocumentRangeFormattingParams &Params) {
-  auto File = Params.textDocument.uri.file;
-  std::string Code = Server.getDocument(File);
-  C.reply(json::ary(
-      replacementsToEdits(Code, Server.formatRange(File, Params.range))));
+  const PathRef File = Params.textDocument.uri.file;
+  auto EditsOrError = Server.formatRange(File, Params.range);
+  if (EditsOrError)
+    C.reply(json::ary{EditsOrError.get()});
+  else
+    C.replyError(EditsOrError.takeError());
 }
 
 void ClangdLSPServer::onDocumentFormatting(Ctx C,
                                            DocumentFormattingParams &Params) {
-  auto File = Params.textDocument.uri.file;
-  std::string Code = Server.getDocument(File);
-  C.reply(json::ary(replacementsToEdits(Code, Server.formatFile(File))));
+  const PathRef File = Params.textDocument.uri.file;
+  auto EditsOrError = Server.formatFile(File);
+  if (EditsOrError)
+    C.reply(json::ary{EditsOrError.get()});
+  else
+    C.replyError(EditsOrError.takeError());
 }
 
 void ClangdLSPServer::onCodeAction(Ctx C, CodeActionParams &Params) {
   // We provide a code action for each diagnostic at the requested location
   // which has FixIts available.
-  std::string Code = Server.getDocument(Params.textDocument.uri.file);
   json::ary Commands;
-  for (Diagnostic &D : Params.context.diagnostics) {
-    std::vector<clang::tooling::Replacement> Fixes =
-        getFixIts(Params.textDocument.uri.file, D);
-    auto Edits = replacementsToEdits(Code, Fixes);
-    if (!Edits.empty()) {
+  for (const auto &Diag : Params.context.diagnostics) {
+    const auto ServerEdits =
+        Server.getFixIts(Params.textDocument.uri.file, Diag);
+    if (!ServerEdits.empty()) {
       WorkspaceEdit WE;
-      WE.changes = {{Params.textDocument.uri.uri, std::move(Edits)}};
+      WE.changes = {
+          {Params.textDocument.uri.uri,
+           std::vector<TextEdit>{ServerEdits.begin(), ServerEdits.end()}}};
       Commands.push_back(json::obj{
-          {"title", llvm::formatv("Apply FixIt {0}", D.message)},
+          {"title", llvm::formatv("Apply FixIt {0}", Diag.message)},
           {"command", ExecuteCommandParams::CLANGD_APPLY_FIX_COMMAND},
           {"arguments", {WE}},
       });
@@ -264,26 +249,10 @@
   return ShutdownRequestReceived;
 }
 
-std::vector<clang::tooling::Replacement>
-ClangdLSPServer::getFixIts(StringRef File, const clangd::Diagnostic &D) {
-  std::lock_guard<std::mutex> Lock(FixItsMutex);
-  auto DiagToFixItsIter = FixItsMap.find(File);
-  if (DiagToFixItsIter == FixItsMap.end())
-    return {};
-
-  const auto &DiagToFixItsMap = DiagToFixItsIter->second;
-  auto FixItsIter = DiagToFixItsMap.find(D);
-  if (FixItsIter == DiagToFixItsMap.end())
-    return {};
-
-  return FixItsIter->second;
-}
-
 void ClangdLSPServer::onDiagnosticsReady(
     PathRef File, Tagged<std::vector<DiagWithFixIts>> Diagnostics) {
   json::ary DiagnosticsJSON;
 
-  DiagnosticToReplacementMap LocalFixIts; // Temporary storage
   for (auto &DiagWithFixes : Diagnostics.Value) {
     auto Diag = DiagWithFixes.Diag;
     DiagnosticsJSON.push_back(json::obj{
@@ -291,27 +260,10 @@
         {"severity", Diag.severity},
         {"message", Diag.message},
     });
-    // We convert to Replacements to become independent of the SourceManager.
-    auto &FixItsForDiagnostic = LocalFixIts[Diag];
-    std::copy(DiagWithFixes.FixIts.begin(), DiagWithFixes.FixIts.end(),
-              std::back_inserter(FixItsForDiagnostic));
-  }
-
-  // Cache FixIts
-  {
-    // FIXME(ibiryukov): should be deleted when documents are removed
-    std::lock_guard<std::mutex> Lock(FixItsMutex);
-    FixItsMap[File] = LocalFixIts;
   }
 
-  // Publish diagnostics.
-  Out.writeMessage(json::obj{
-      {"jsonrpc", "2.0"},
-      {"method", "textDocument/publishDiagnostics"},
-      {"params",
-       json::obj{
-           {"uri", URI::fromFile(File)},
-           {"diagnostics", std::move(DiagnosticsJSON)},
-       }},
-  });
+  // Publish diagnostics by sending an LSP notification to the client.
+  Out.notify("textDocument/publishDiagnostics",
+             json::obj{{"uri", URI::fromFile(File)},
+                       {"diagnostics", std::move(DiagnosticsJSON)}});
 }
Index: clangd/ClangdServer.h
===================================================================
--- clangd/ClangdServer.h
+++ clangd/ClangdServer.h
@@ -284,16 +284,24 @@
   /// given a header file and vice versa.
   llvm::Optional<Path> switchSourceHeader(PathRef Path);
 
-  /// Run formatting for \p Rng inside \p File.
-  std::vector<tooling::Replacement> formatRange(PathRef File, Range Rng);
-  /// Run formatting for the whole \p File.
-  std::vector<tooling::Replacement> formatFile(PathRef File);
-  /// Run formatting after a character was typed at \p Pos in \p File.
-  std::vector<tooling::Replacement> formatOnType(PathRef File, Position Pos);
+  /// Get "FixIt" replacements for the given diagnostic.
+  llvm::SmallVector<TextEdit, 1> getFixIts(StringRef File,
+                                           const clangd::Diagnostic &D);
+
+  /// Run formatting for \p Rng inside \p File with content \p Code.
+  llvm::Expected<std::vector<TextEdit>> formatRange(PathRef File, Range Rng);
   /// Rename all occurrences of the symbol at the \p Pos in \p File to
   /// \p NewName.
-  Expected<std::vector<tooling::Replacement>> rename(PathRef File, Position Pos,
-                                                     llvm::StringRef NewName);
+  Expected<std::vector<TextEdit>> rename(PathRef File, Position Pos,
+                                         llvm::StringRef NewName);
+
+  /// Run formatting for the whole \p File with content \p Code.
+  llvm::Expected<std::vector<TextEdit>> formatFile(PathRef File);
+
+  /// Run formatting after a character was typed at \p Pos in \p File with
+  /// content \p Code.
+  llvm::Expected<std::vector<TextEdit>> formatOnType(PathRef File,
+                                                     Position Pos);
 
   /// Gets current document contents for \p File. \p File must point to a
   /// currently tracked file.
@@ -309,6 +317,12 @@
   void onFileEvent(const DidChangeWatchedFilesParams &Params);
 
 private:
+  /// FIXME: This stats several files to find a .clang-format file. I/O can be
+  /// slow. Think of a way to cache this.
+  llvm::Expected<std::vector<TextEdit>>
+  formatCode(llvm::StringRef Code, PathRef File,
+             ArrayRef<tooling::Range> Ranges);
+
   std::future<void>
   scheduleReparseAndDiags(PathRef File, VersionedDraft Contents,
                           std::shared_ptr<CppFile> Resources,
@@ -334,6 +348,11 @@
   std::mutex DiagnosticsMutex;
   /// Maps from a filename to the latest version of reported diagnostics.
   llvm::StringMap<DocVersion> ReportedDiagnosticVersions;
+  std::mutex FixItsMutex;
+  typedef std::map<clangd::Diagnostic, llvm::SmallVector<TextEdit, 1>>
+      DiagnosticToTextEditMap;
+  /// Caches FixIts per file and diagnostics
+  llvm::StringMap<DiagnosticToTextEditMap> FixItsMap;
   // WorkScheduler has to be the last member, because its destructor has to be
   // called before all other members to stop the worker thread that references
   // ClangdServer
Index: clangd/ClangdServer.cpp
===================================================================
--- clangd/ClangdServer.cpp
+++ clangd/ClangdServer.cpp
@@ -28,6 +28,35 @@
 
 namespace {
 
+TextEdit replacementToEdit(StringRef Code,
+                           const tooling::Replacement &Replacement) {
+  TextEdit Edit;
+  Edit.range = {offsetToPosition(Code, Replacement.getOffset()),
+                offsetToPosition(Code, Replacement.getOffset() +
+                                           Replacement.getLength())};
+  Edit.newText = Replacement.getReplacementText();
+  return Edit;
+}
+
+template <class ForwardIterator>
+std::vector<TextEdit> replacementsToEdits(StringRef Code, ForwardIterator Begin,
+                                          ForwardIterator End) {
+  // Turn the replacements into the format specified by the Language Server
+  // Protocol. Fuse them into one big JSON array.
+  std::vector<TextEdit> Edits;
+  Edits.reserve(std::distance(Begin, End));
+  while (Begin != End) {
+    Edits.emplace_back(replacementToEdit(Code, *Begin));
+    ++Begin;
+  }
+  return Edits;
+}
+
+std::vector<TextEdit> replacementsToEdits(StringRef Code,
+                                          tooling::Replacements Replacements) {
+  return replacementsToEdits(Code, Replacements.begin(), Replacements.end());
+}
+
 class FulfillPromiseGuard {
 public:
   FulfillPromiseGuard(std::promise<void> &Promise) : Promise(Promise) {}
@@ -38,16 +67,6 @@
   std::promise<void> &Promise;
 };
 
-std::vector<tooling::Replacement> formatCode(StringRef Code, StringRef Filename,
-                                             ArrayRef<tooling::Range> Ranges) {
-  // Call clang-format.
-  // FIXME: Don't ignore style.
-  format::FormatStyle Style = format::getLLVMStyle();
-  auto Result = format::reformat(Style, Code, Ranges, Filename);
-
-  return std::vector<tooling::Replacement>(Result.begin(), Result.end());
-}
-
 std::string getStandardResourceDir() {
   static int Dummy; // Just an address in this process.
   return CompilerInvocation::GetResourcesPath("clangd", (void *)&Dummy);
@@ -204,6 +223,7 @@
 std::future<void> ClangdServer::removeDocument(PathRef File) {
   DraftMgr.removeDraft(File);
   std::shared_ptr<CppFile> Resources = Units.removeIfPresent(File);
+  FixItsMap.erase(File);
   return scheduleCancelRebuild(std::move(Resources));
 }
 
@@ -329,28 +349,27 @@
   return make_tagged(std::move(Result), TaggedFS.Tag);
 }
 
-std::vector<tooling::Replacement> ClangdServer::formatRange(PathRef File,
-                                                            Range Rng) {
-  std::string Code = getDocument(File);
-
+llvm::Expected<std::vector<TextEdit>> ClangdServer::formatRange(PathRef File,
+                                                                Range Rng) {
+  const auto Code = getDocument(File);
   size_t Begin = positionToOffset(Code, Rng.start);
   size_t Len = positionToOffset(Code, Rng.end) - Begin;
   return formatCode(Code, File, {tooling::Range(Begin, Len)});
 }
 
-std::vector<tooling::Replacement> ClangdServer::formatFile(PathRef File) {
+llvm::Expected<std::vector<TextEdit>> ClangdServer::formatFile(PathRef File) {
   // Format everything.
-  std::string Code = getDocument(File);
+  const auto Code = getDocument(File);
   return formatCode(Code, File, {tooling::Range(0, Code.size())});
 }
 
-std::vector<tooling::Replacement> ClangdServer::formatOnType(PathRef File,
-                                                             Position Pos) {
+llvm::Expected<std::vector<TextEdit>> ClangdServer::formatOnType(PathRef File,
+                                                                 Position Pos) {
+  const auto Code = getDocument(File);
   // Look for the previous opening brace from the character position and
   // format starting from there.
-  std::string Code = getDocument(File);
   size_t CursorPos = positionToOffset(Code, Pos);
-  size_t PreviousLBracePos = StringRef(Code).find_last_of('{', CursorPos);
+  size_t PreviousLBracePos = Code.find_last_of('{', CursorPos);
   if (PreviousLBracePos == StringRef::npos)
     PreviousLBracePos = CursorPos;
   size_t Len = 1 + CursorPos - PreviousLBracePos;
@@ -358,8 +377,8 @@
   return formatCode(Code, File, {tooling::Range(PreviousLBracePos, Len)});
 }
 
-Expected<std::vector<tooling::Replacement>>
-ClangdServer::rename(PathRef File, Position Pos, llvm::StringRef NewName) {
+Expected<std::vector<TextEdit>> ClangdServer::rename(PathRef File, Position Pos,
+                                                     llvm::StringRef NewName) {
   std::string Code = getDocument(File);
   std::shared_ptr<CppFile> Resources = Units.getFile(File);
   RefactoringResultCollector ResultCollector;
@@ -386,7 +405,7 @@
   if (!ResultCollector.Result.getValue())
     return ResultCollector.Result->takeError();
 
-  std::vector<tooling::Replacement> Replacements;
+  std::vector<TextEdit> Edits;
   for (const tooling::AtomicChange &Change : ResultCollector.Result->get()) {
     tooling::Replacements ChangeReps = Change.getReplacements();
     for (const auto &Rep : ChangeReps) {
@@ -400,10 +419,10 @@
       //   * rename globally in project
       //   * rename in open files
       if (Rep.getFilePath() == File)
-        Replacements.push_back(Rep);
+        Edits.push_back(replacementToEdit(Code, Rep));
     }
   }
-  return Replacements;
+  return Edits;
 }
 
 std::string ClangdServer::getDocument(PathRef File) {
@@ -507,6 +526,36 @@
   return llvm::None;
 }
 
+llvm::SmallVector<TextEdit, 1>
+ClangdServer::getFixIts(StringRef File, const clangd::Diagnostic &D) {
+  std::lock_guard<std::mutex> Lock(FixItsMutex);
+  auto DiagToFixItsIter = FixItsMap.find(File);
+  if (DiagToFixItsIter == FixItsMap.end())
+    return {};
+
+  const auto &DiagToFixItsMap = DiagToFixItsIter->second;
+  auto FixItsIter = DiagToFixItsMap.find(D);
+  if (FixItsIter == DiagToFixItsMap.end())
+    return {};
+
+  return FixItsIter->second;
+}
+
+llvm::Expected<std::vector<TextEdit>>
+ClangdServer::formatCode(llvm::StringRef Code, PathRef File,
+                         ArrayRef<tooling::Range> Ranges) {
+  // Call clang-format.
+  auto TaggedFS = FSProvider.getTaggedFileSystem(File);
+  auto StyleOrError =
+      format::getStyle("file", File, "LLVM", Code, TaggedFS.Value.get());
+  if (!StyleOrError) {
+    return StyleOrError.takeError();
+  } else {
+    return replacementsToEdits(
+        Code, format::reformat(StyleOrError.get(), Code, Ranges, File));
+  }
+}
+
 std::future<void> ClangdServer::scheduleReparseAndDiags(
     PathRef File, VersionedDraft Contents, std::shared_ptr<CppFile> Resources,
     Tagged<IntrusiveRefCntPtr<vfs::FileSystem>> TaggedFS) {
@@ -548,6 +597,14 @@
       return;
     LastReportedDiagsVersion = Version;
 
+    // Cache FixIts for when the client requests textDocument/codeAction.
+    DiagnosticToTextEditMap M;
+    for (const auto& Diag : *Diags) M.emplace(Diag.Diag, Diag.FixIts);
+    {
+      std::unique_lock<std::mutex> Guard(FixItsMutex);
+      FixItsMap[FileStr] = M;
+    }
+
     DiagConsumer.onDiagnosticsReady(FileStr,
                                     make_tagged(std::move(*Diags), Tag));
   };
Index: clangd/ClangdUnit.h
===================================================================
--- clangd/ClangdUnit.h
+++ clangd/ClangdUnit.h
@@ -45,7 +45,7 @@
 /// A diagnostic with its FixIts.
 struct DiagWithFixIts {
   clangd::Diagnostic Diag;
-  llvm::SmallVector<tooling::Replacement, 1> FixIts;
+  llvm::SmallVector<TextEdit, 1> FixIts;
 };
 
 // Stores Preamble and associated data.
Index: clangd/ClangdUnit.cpp
===================================================================
--- clangd/ClangdUnit.cpp
+++ clangd/ClangdUnit.cpp
@@ -158,21 +158,41 @@
   return Result;
 }
 
+/// Convert a SourceLocation to a Position
+Position SourceLocToPosition(const SourceManager &SrcMgr,
+                             SourceLocation Location) {
+  Position P;
+  // LSP rows and columns are 0-based, clang rows and columns are 1-based.
+  P.line = static_cast<int>(SrcMgr.getSpellingLineNumber(Location)) - 1;
+  P.character = static_cast<int>(SrcMgr.getSpellingColumnNumber(Location)) - 1;
+  assert(P.line >= 0 && "Unexpected negative value for P.line");
+  assert(P.character >= 0 && "Unepxected negative value for P.character");
+  return P;
+}
+
+/// Convert a FullSourceLoc to a Position
+Position SourceLocToPosition(const FullSourceLoc &Location) {
+  return SourceLocToPosition(Location.getManager(), Location);
+}
+
 llvm::Optional<DiagWithFixIts> toClangdDiag(const StoredDiagnostic &D) {
-  auto Location = D.getLocation();
-  if (!Location.isValid() || !Location.getManager().isInMainFile(Location))
+  const auto &Location = D.getLocation();
+  const auto &SrcMgr = Location.getManager();
+  if (!Location.isValid() || !SrcMgr.isInMainFile(Location))
     return llvm::None;
 
-  Position P;
-  P.line = Location.getSpellingLineNumber() - 1;
-  P.character = Location.getSpellingColumnNumber();
+  const auto P = SourceLocToPosition(Location);
   Range R = {P, P};
   clangd::Diagnostic Diag = {R, getSeverity(D.getLevel()), D.getMessage()};
 
-  llvm::SmallVector<tooling::Replacement, 1> FixItsForDiagnostic;
+  llvm::SmallVector<TextEdit, 1> FixItsForDiagnostic;
   for (const FixItHint &Fix : D.getFixIts()) {
-    FixItsForDiagnostic.push_back(clang::tooling::Replacement(
-        Location.getManager(), Fix.RemoveRange, Fix.CodeToInsert));
+    Range ReplacementRange;
+    ReplacementRange.start =
+        SourceLocToPosition(SrcMgr, Fix.RemoveRange.getBegin());
+    ReplacementRange.end =
+        SourceLocToPosition(SrcMgr, Fix.RemoveRange.getEnd());
+    FixItsForDiagnostic.push_back({ReplacementRange, Fix.CodeToInsert});
   }
   return DiagWithFixIts{Diag, std::move(FixItsForDiagnostic)};
 }
Index: clangd/JSONRPCDispatcher.h
===================================================================
--- clangd/JSONRPCDispatcher.h
+++ clangd/JSONRPCDispatcher.h
@@ -17,6 +17,7 @@
 #include "clang/Basic/LLVM.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringMap.h"
+#include "llvm/Support/Error.h"
 #include "llvm/Support/YAMLParser.h"
 #include <iosfwd>
 #include <mutex>
@@ -44,6 +45,9 @@
   /// Unlike other methods of JSONOutput, mirrorInput is not thread-safe.
   void mirrorInput(const Twine &Message);
 
+  /// Send a notification to the client.
+  void notify(llvm::StringRef Method, json::Expr &&Params);
+
 private:
   llvm::raw_ostream &Outs;
   llvm::raw_ostream &Logs;
@@ -64,11 +68,13 @@
       SPAN_ATTACH(tracer(), "ID", *this->ID);
   }
 
-  /// Sends a successful reply.
+  /// Send a response to a request from the client.
   void reply(json::Expr &&Result);
-  /// Sends an error response to the client, and logs it.
+  /// Send an error response to the client, and logs it.
   void replyError(ErrorCode code, const llvm::StringRef &Message);
-  /// Sends a request to the client.
+  /// Send all error messages contained in Err to the client, and log them.
+  void replyError(llvm::Error Err);
+  /// Send a request to the client.
   void call(llvm::StringRef Method, json::Expr &&Params);
 
   trace::Span &tracer() { return *Tracer; }
Index: clangd/JSONRPCDispatcher.cpp
===================================================================
--- clangd/JSONRPCDispatcher.cpp
+++ clangd/JSONRPCDispatcher.cpp
@@ -39,6 +39,14 @@
   Outs.flush();
 }
 
+void JSONOutput::notify(StringRef Method, json::Expr &&Params) {
+  writeMessage(json::obj{
+    {"jsonrpc", "2.0"},
+    {"method", Method},
+    {"params", std::move(Params)},
+  });
+}
+
 void JSONOutput::log(const Twine &Message) {
   trace::log(Message);
   std::lock_guard<std::mutex> Guard(StreamMutex);
@@ -83,6 +91,11 @@
   }
 }
 
+void RequestContext::replyError(llvm::Error Err) {
+  const auto Message = llvm::toString(std::move(Err));
+  replyError(ErrorCode::UnknownErrorCode, Message);
+}
+
 void RequestContext::call(StringRef Method, json::Expr &&Params) {
   // FIXME: Generate/Increment IDs for every request so that we can get proper
   // replies once we need to.
Index: test/clangd/diagnostics.test
===================================================================
--- test/clangd/diagnostics.test
+++ test/clangd/diagnostics.test
@@ -15,11 +15,11 @@
 # CHECK-NEXT:        "message": "return type of 'main' is not 'int'",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 1,
+# CHECK-NEXT:            "character": 0,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 1,
+# CHECK-NEXT:            "character": 0,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -29,11 +29,11 @@
 # CHECK-NEXT:        "message": "change return type to 'int'",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 1,
+# CHECK-NEXT:            "character": 0,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 1,
+# CHECK-NEXT:            "character": 0,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
Index: test/clangd/execute-command.test
===================================================================
--- test/clangd/execute-command.test
+++ test/clangd/execute-command.test
@@ -15,11 +15,11 @@
 # CHECK-NEXT:        "message": "using the result of an assignment as a condition without parentheses",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -29,11 +29,11 @@
 # CHECK-NEXT:        "message": "place parentheses around the assignment to silence this warning",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -43,11 +43,11 @@
 # CHECK-NEXT:        "message": "use '==' to turn this assignment into an equality comparison",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
Index: test/clangd/extra-flags.test
===================================================================
--- test/clangd/extra-flags.test
+++ test/clangd/extra-flags.test
@@ -15,11 +15,11 @@
 # CHECK-NEXT:        "message": "variable 'i' is uninitialized when used here",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 28,
+# CHECK-NEXT:            "character": 27,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 28,
+# CHECK-NEXT:            "character": 27,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -29,11 +29,11 @@
 # CHECK-NEXT:        "message": "initialize the variable 'i' to silence this warning",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 19,
+# CHECK-NEXT:            "character": 18,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 19,
+# CHECK-NEXT:            "character": 18,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -52,11 +52,11 @@
 # CHECK-NEXT:        "message": "variable 'i' is uninitialized when used here",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 28,
+# CHECK-NEXT:            "character": 27,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 28,
+# CHECK-NEXT:            "character": 27,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -66,11 +66,11 @@
 # CHECK-NEXT:        "message": "initialize the variable 'i' to silence this warning",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 19,
+# CHECK-NEXT:            "character": 18,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 19,
+# CHECK-NEXT:            "character": 18,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
Index: test/clangd/fixits.test
===================================================================
--- test/clangd/fixits.test
+++ test/clangd/fixits.test
@@ -15,11 +15,11 @@
 # CHECK-NEXT:        "message": "using the result of an assignment as a condition without parentheses",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -29,11 +29,11 @@
 # CHECK-NEXT:        "message": "place parentheses around the assignment to silence this warning",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -43,11 +43,11 @@
 # CHECK-NEXT:        "message": "use '==' to turn this assignment into an equality comparison",
 # CHECK-NEXT:        "range": {
 # CHECK-NEXT:          "end": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          },
 # CHECK-NEXT:          "start": {
-# CHECK-NEXT:            "character": 35,
+# CHECK-NEXT:            "character": 34,
 # CHECK-NEXT:            "line": 0
 # CHECK-NEXT:          }
 # CHECK-NEXT:        },
@@ -58,7 +58,7 @@
 # CHECK-NEXT:  }
 Content-Length: 746
 
-{"jsonrpc":"2.0","id":2,"method":"textDocument/codeAction","params":{"textDocument":{"uri":"file:///foo.c"},"range":{"start":{"line":104,"character":13},"end":{"line":0,"character":35}},"context":{"diagnostics":[{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":2,"message":"using the result of an assignment as a condition without parentheses"},{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":3,"message":"place parentheses around the assignment to silence this warning"},{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":3,"message":"use '==' to turn this assignment into an equality comparison"}]}}}
+{"jsonrpc":"2.0","id":2,"method":"textDocument/codeAction","params":{"textDocument":{"uri":"file:///foo.c"},"range":{"start":{"line":104,"character":13},"end":{"line":0,"character":34}},"context":{"diagnostics":[{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":2,"message":"using the result of an assignment as a condition without parentheses"},{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":3,"message":"place parentheses around the assignment to silence this warning"},{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":3,"message":"use '==' to turn this assignment into an equality comparison"}]}}}
 #      CHECK:  "id": 2,
 # CHECK-NEXT:  "jsonrpc": "2.0",
 # CHECK-NEXT:  "result": [
@@ -109,7 +109,7 @@
 # CHECK-NEXT:                "newText": "==",
 # CHECK-NEXT:                "range": {
 # CHECK-NEXT:                  "end": {
-# CHECK-NEXT:                    "character": 35,
+# CHECK-NEXT:                    "character": 34,
 # CHECK-NEXT:                    "line": 0
 # CHECK-NEXT:                  },
 # CHECK-NEXT:                  "start": {
@@ -128,7 +128,7 @@
 # CHECK-NEXT:  ]
 Content-Length: 771
 
-{"jsonrpc":"2.0","id":3,"method":"textDocument/codeAction","params":{"textDocument":{"uri":"file:///foo.c"},"range":{"start":{"line":104,"character":13},"end":{"line":0,"character":35}},"context":{"diagnostics":[{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":2,"code":"1","source":"foo","message":"using the result of an assignment as a condition without parentheses"},{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":3,"message":"place parentheses around the assignment to silence this warning"},{"range":{"start": {"line": 0, "character": 35}, "end": {"line": 0, "character": 35}},"severity":3,"message":"use '==' to turn this assignment into an equality comparison"}]}}}
+{"jsonrpc":"2.0","id":3,"method":"textDocument/codeAction","params":{"textDocument":{"uri":"file:///foo.c"},"range":{"start":{"line":104,"character":13},"end":{"line":0,"character":34}},"context":{"diagnostics":[{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":2,"code":"1","source":"foo","message":"using the result of an assignment as a condition without parentheses"},{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":3,"message":"place parentheses around the assignment to silence this warning"},{"range":{"start": {"line": 0, "character": 34}, "end": {"line": 0, "character": 34}},"severity":3,"message":"use '==' to turn this assignment into an equality comparison"}]}}}
 # Make sure unused "code" and "source" fields ignored gracefully
 #      CHECK:  "id": 3,
 # CHECK-NEXT:  "jsonrpc": "2.0",
@@ -180,7 +180,7 @@
 # CHECK-NEXT:                "newText": "==",
 # CHECK-NEXT:                "range": {
 # CHECK-NEXT:                  "end": {
-# CHECK-NEXT:                    "character": 35,
+# CHECK-NEXT:                    "character": 34,
 # CHECK-NEXT:                    "line": 0
 # CHECK-NEXT:                  },
 # CHECK-NEXT:                  "start": {