[clangd] Extend textDocument/didChange to specify whether diagnostics should be generated.

Summary:
This would allow us to disable diagnostics when didChange is called but
diagnostics are not wanted (e.g. code completion).

Reviewers: sammccall

Subscribers: klimek, ilya-biryukov, jkorous-apple, cfe-commits

Differential Revision: https://reviews.llvm.org/D43634

llvm-svn: 325813

3 files changed, 13 insertions, 2 deletions

diff --git a/clang-tools-extra/clangd/ClangdLSPServer.cpp b/clang-tools-extra/clangd/ClangdLSPServer.cpp
index 587aee73ae0..f2c46dc8d3d 100644
--- a/clang-tools-extra/clangd/ClangdLSPServer.cpp
+++ b/clang-tools-extra/clangd/ClangdLSPServer.cpp
@@ -149,9 +149,13 @@ void ClangdLSPServer::onDocumentDidChange(DidChangeTextDocumentParams &Params) {
   if (Params.contentChanges.size() != 1)
     return replyError(ErrorCode::InvalidParams,
                       "can only apply one change at a time");
+  auto WantDiags = WantDiagnostics::Auto;
+  if (Params.wantDiagnostics.hasValue())
+    WantDiags = Params.wantDiagnostics.getValue() ? WantDiagnostics::Yes
+                                                  : WantDiagnostics::No;
   // We only support full syncing right now.
   Server.addDocument(Params.textDocument.uri.file(),
-                     Params.contentChanges[0].text, WantDiagnostics::Auto);
+                     Params.contentChanges[0].text, WantDiags);
 }
 
 void ClangdLSPServer::onFileEvent(DidChangeWatchedFilesParams &Params) {
diff --git a/clang-tools-extra/clangd/Protocol.cpp b/clang-tools-extra/clangd/Protocol.cpp
index 89925992579..799b2a116aa 100644
--- a/clang-tools-extra/clangd/Protocol.cpp
+++ b/clang-tools-extra/clangd/Protocol.cpp
@@ -221,7 +221,8 @@ bool fromJSON(const json::Expr &Params, DidCloseTextDocumentParams &R) {
 bool fromJSON(const json::Expr &Params, DidChangeTextDocumentParams &R) {
   json::ObjectMapper O(Params);
   return O && O.map("textDocument", R.textDocument) &&
-         O.map("contentChanges", R.contentChanges);
+         O.map("contentChanges", R.contentChanges) &&
+         O.map("wantDiagnostics", R.wantDiagnostics);
 }
 
 bool fromJSON(const json::Expr &E, FileChangeType &Out) {
diff --git a/clang-tools-extra/clangd/Protocol.h b/clang-tools-extra/clangd/Protocol.h
index 40ccfaf49cb..2db30e74db9 100644
--- a/clang-tools-extra/clangd/Protocol.h
+++ b/clang-tools-extra/clangd/Protocol.h
@@ -297,6 +297,12 @@ struct DidChangeTextDocumentParams {
 
   /// The actual content changes.
   std::vector<TextDocumentContentChangeEvent> contentChanges;
+
+  /// Forces diagnostics to be generated, or to not be generated, for this
+  /// version of the file. If not set, diagnostics are eventually consistent:
+  /// either they will be provided for this version or some subsequent one.
+  /// This is a clangd extension.
+  llvm::Optional<bool> wantDiagnostics;
 };
 bool fromJSON(const json::Expr &, DidChangeTextDocumentParams &);