[clangd] Add hidden tweaks to dump AST/selection.

Summary:
This introduces a few new concepts:
 - tweaks have an Intent (they don't all advertise as refactorings)
 - tweaks may produce messages (for ShowMessage notification). Generalized
   Replacements -> Effect.
 - tweaks (and other features) may be hidden (clangd -hidden-features flag).
   We may choose to promote these one day. I'm not sure they're worth their own
   feature flags though.

Verified it in vim-clangd (not yet open source), curious if the UI is ok in VSCode.

Reviewers: ilya-biryukov

Subscribers: mgorny, MaskRay, jkorous, arphaman, kadircet, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62538

llvm-svn: 363680

1 files changed, 9 insertions, 0 deletions

diff --git a/clang-tools-extra/clangd/Protocol.cpp b/clang-tools-extra/clangd/Protocol.cpp
index 17d070a3f7b..f8becaaa361 100644
--- a/clang-tools-extra/clangd/Protocol.cpp
+++ b/clang-tools-extra/clangd/Protocol.cpp
@@ -359,6 +359,14 @@ bool fromJSON(const llvm::json::Value &Params, InitializeParams &R) {
   return true;
 }
 
+llvm::json::Value toJSON(const MessageType &R) {
+  return static_cast<int64_t>(R);
+}
+
+llvm::json::Value toJSON(const ShowMessageParams &R) {
+  return llvm::json::Object{{"type", R.type}, {"message", R.message}};
+}
+
 bool fromJSON(const llvm::json::Value &Params, DidOpenTextDocumentParams &R) {
   llvm::json::ObjectMapper O(Params);
   return O && O.map("textDocument", R.textDocument);
@@ -593,6 +601,7 @@ llvm::json::Value toJSON(const Command &C) {
 
 const llvm::StringLiteral CodeAction::QUICKFIX_KIND = "quickfix";
 const llvm::StringLiteral CodeAction::REFACTOR_KIND = "refactor";
+const llvm::StringLiteral CodeAction::INFO_KIND = "info";
 
 llvm::json::Value toJSON(const CodeAction &CA) {
   auto CodeAction = llvm::json::Object{{"title", CA.title}};