Refactor ReplyOnce; error if InitializeParams.rootUri is null

src/lsp.hh

@@ -62,15 +62,8 @@ enum class ErrorCode {
 };
 
 struct ResponseError {
-  // A number indicating the error type that occurred.
   ErrorCode code;
-
-  // A string providing a short description of the error.
   std::string message;
-
-  // A Primitive or Structured value that contains additional
-  // information about the error. Can be omitted.
-  // std::optional<D> data;
 };
 
 constexpr char ccls_xref[] = "ccls.xref";

src/message_handler.cc

@@ -207,21 +207,13 @@ void MessageHandler::Run(InMessage &msg) {
       try {
         it->second(reader, reply);
       } catch (std::invalid_argument &ex) {
-        ResponseError err;
+        reply.Error(ErrorCode::InvalidParams,
-        err.code = ErrorCode::InvalidParams;
+                    "invalid params of " + msg.method + ": " + ex.what());
-        err.message = "invalid params of " + msg.method + ": " + ex.what();
-        reply.Error(err);
       } catch (...) {
-        ResponseError err;
+        reply.Error(ErrorCode::InternalError, "failed to process " + msg.method);
-        err.code = ErrorCode::InternalError;
-        err.message = "failed to process " + msg.method;
-        reply.Error(err);
       }
     } else {
-      ResponseError err;
+      reply.Error(ErrorCode::MethodNotFound, "unknown request " + msg.method);
-      err.code = ErrorCode::MethodNotFound;
-      err.message = "unknown request " + msg.method;
-      reply.Error(err);
     }
   } else {
     auto it = method2notification.find(msg.method);
@@ -260,14 +252,10 @@ QueryFile *MessageHandler::FindFile(ReplyOnce &reply,
         has_entry |= folder.path2entry_index.count(path);
     }
     ResponseError err;
-    if (has_entry) {
+    if (has_entry)
-      err.code = ErrorCode::ServerNotInitialized;
+      reply.Error(ErrorCode::ServerNotInitialized, path + " is being indexed");
-      err.message = path + " is being indexed";
+    else
-    } else {
+      reply.Error(ErrorCode::InternalError, "unable to find " + path);
-      err.code = ErrorCode::InternalError;
-      err.message = "unable to find " + path;
-    }
-    reply.Error(err);
   }
 
   return ret;

src/message_handler.hh

@@ -194,17 +194,14 @@ MAKE_REFLECT_STRUCT(Diagnostic, range, severity, code, source, message);
 MAKE_REFLECT_STRUCT(ShowMessageParam, type, message);
 MAKE_REFLECT_TYPE_PROXY(LanguageId);
 
-// TODO llvm 8 llvm::unique_function
-template <typename Res>
-using Callback = std::function<void(Res*)>;
-
 struct ReplyOnce {
   RequestId id;
-  template <typename Res> void operator()(Res &result) const {
+  template <typename Res> void operator()(Res &&result) const {
     if (id.Valid())
       pipeline::Reply(id, [&](Writer &w) { Reflect(w, result); });
   }
-  template <typename Err> void Error(Err &err) const {
+  void Error(ErrorCode code, std::string message) const {
+    ResponseError err{code, std::move(message)};
     if (id.Valid())
       pipeline::ReplyError(id, [&](Writer &w) { Reflect(w, err); });
   }

src/messages/ccls_call.cc

@@ -216,9 +216,7 @@ void MessageHandler::ccls_call(Reader &reader, ReplyOnce &reply) {
 
   if (param.hierarchy)
     reply(result);
-  else {
+  else
-    auto out = FlattenHierarchy(result);
+    reply(FlattenHierarchy(result));
-    reply(out);
-  }
 }
 } // namespace ccls

src/messages/ccls_inheritance.cc

@@ -161,10 +161,8 @@ void Inheritance(MessageHandler *m, Param &param, ReplyOnce &reply) {
 
   if (param.hierarchy)
     reply(result);
-  else {
+  else
-    auto out = FlattenHierarchy(result);
+    reply(FlattenHierarchy(result));
-    reply(out);
-  }
 }
 } // namespace
 

src/messages/ccls_member.cc

@@ -309,9 +309,7 @@ void MessageHandler::ccls_member(Reader &reader, ReplyOnce &reply) {
 
   if (param.hierarchy)
     reply(result);
-  else {
+  else
-    auto out = FlattenHierarchy(result);
+    reply(FlattenHierarchy(result));
-    reply(out);
-  }
 }
 } // namespace ccls

src/messages/initialize.cc

@@ -292,10 +292,7 @@ void Initialize(MessageHandler *m, InitializeParam &param, ReplyOnce &reply) {
 
   // Send initialization before starting indexers, so we don't send a
   // status update too early.
-  {
+  reply(InitializeResult{});
-    InitializeResult result;
-    reply(result);
-  }
 
   // Set project root.
   EnsureEndsInSlash(project_path);
@@ -342,8 +339,10 @@ void Initialize(MessageHandler *m, InitializeParam &param, ReplyOnce &reply) {
 void MessageHandler::initialize(Reader &reader, ReplyOnce &reply) {
   InitializeParam param;
   Reflect(reader, param);
-  if (!param.rootUri)
+  if (!param.rootUri) {
+    reply.Error(ErrorCode::InvalidRequest, "expected rootUri");
     return;
+  }
   Initialize(this, param, reply);
 }
 
@@ -355,8 +354,7 @@ void StandaloneInitialize(MessageHandler &handler, const std::string &root) {
 }
 
 void MessageHandler::shutdown(EmptyParam &, ReplyOnce &reply) {
-  JsonNull result;
+  reply(JsonNull{});
-  reply(result);
 }
 
 void MessageHandler::exit(EmptyParam &) {

src/messages/textDocument_formatting.cc

@@ -70,15 +70,11 @@ std::vector<TextEdit> ReplacementsToEdits(std::string_view code,
 void Format(ReplyOnce &reply, WorkingFile *wfile, tooling::Range range) {
   std::string_view code = wfile->buffer_content;
   auto ReplsOrErr = FormatCode(code, wfile->filename, range);
-  if (ReplsOrErr) {
+  if (ReplsOrErr)
-    auto result = ReplacementsToEdits(code, *ReplsOrErr);
+    reply(ReplacementsToEdits(code, *ReplsOrErr));
-    reply(result);
+  else
-  } else {
+    reply.Error(ErrorCode::UnknownErrorCode,
-    ResponseError err;
+                llvm::toString(ReplsOrErr.takeError()));
-    err.code = ErrorCode::UnknownErrorCode;
-    err.message = llvm::toString(ReplsOrErr.takeError());
-    reply.Error(err);
-  }
 }
 } // namespace