Updated reciever to handle null params slightly differently, and changed how Request Routers router requests

Author: david-driscoll

src/JsonRpc/Reciever.cs

@@ -88,7 +88,7 @@ protected virtual Renor GetRenor(JToken @object)
             // that we don't fall over and throw an error.
             if (@params?.Type == JTokenType.Null)
             {
-                @params = null;
+                @params = new JObject();
             }
 
             // id == request

src/JsonRpc/ReflectionRequestHandlers.cs

@@ -1,4 +1,4 @@
-using System.Reflection;
+using System.Reflection;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -22,14 +22,6 @@ public static Task HandleNotification(IHandlerDescriptor instance, object @param
             return (Task)method.Invoke(instance.Handler, new[] { @params });
         }
 
-        public static Task HandleRequest(IHandlerDescriptor instance, CancellationToken token)
-        {
-            var method = instance.HandlerType.GetTypeInfo()
-                .GetMethod(nameof(IRequestHandler<object>.Handle), BindingFlags.Public | BindingFlags.Instance);
-
-            return (Task)method.Invoke(instance.Handler, new object[] { token });
-        }
-
         public static Task HandleRequest(IHandlerDescriptor instance, object @params, CancellationToken token)
         {
             var method = instance.HandlerType.GetTypeInfo()
@@ -38,4 +30,4 @@ public static Task HandleRequest(IHandlerDescriptor instance, object @params, Ca
             return (Task)method.Invoke(instance.Handler, new[] { @params, token });
         }
     }
-}
+}

src/JsonRpc/RequestRouter.cs

@@ -56,13 +56,6 @@ protected virtual async Task<ErrorResponse> RouteRequest(IHandlerDescriptor hand
                 return new MethodNotFound(request.Id, request.Method);
             }
 
-            Task result;
-            if (handler.Params is null)
-            {
-                result = ReflectionRequestHandlers.HandleRequest(handler, token);
-            }
-            else
-            {
                 object @params;
                 try
                 {
@@ -73,8 +66,7 @@ protected virtual async Task<ErrorResponse> RouteRequest(IHandlerDescriptor hand
                     return new InvalidParams(request.Id);
                 }
 
-                result = ReflectionRequestHandlers.HandleRequest(handler, @params, token);
-            }
+                var result = ReflectionRequestHandlers.HandleRequest(handler, @params, token);
 
             await result.ConfigureAwait(false);
 

src/Server/LspRequestRouter.cs

@@ -111,27 +111,18 @@ public async Task<ErrorResponse> RouteRequest(IHandlerDescriptor descriptor, Req
                     return new MethodNotFound(request.Id, request.Method);
                 }
 
-                Task result;
-                if (descriptor.Params is null)
+                object @params;
+                try
                 {
-                    result = ReflectionRequestHandlers.HandleRequest(descriptor, cts.Token);
+                    @params = request.Params?.ToObject(descriptor.Params, _serializer.JsonSerializer);
                 }
-                else
+                catch
                 {
-                    object @params;
-                    try
-                    {
-                        @params = request.Params.ToObject(descriptor.Params, _serializer.JsonSerializer);
-                    }
-                    catch
-                    {
-                        return new InvalidParams(request.Id);
-                    }
-
-                    result = ReflectionRequestHandlers.HandleRequest(descriptor, @params, cts.Token);
+                    return new InvalidParams(request.Id);
                 }
 
-                await result.ConfigureAwait(false);
+                var result = ReflectionRequestHandlers.HandleRequest(descriptor, @params, cts.Token).ConfigureAwait(false);
+                await result;
 
                 object responseValue = null;
                 if (result.GetType().GetTypeInfo().IsGenericType)

test/JsonRpc.Tests/Server/SpecifictionRecieverTests.cs

@@ -71,7 +71,7 @@ public override IEnumerable<ValueTuple<string, Renor[]>> GetValues()
                     @"{""jsonrpc"": ""2.0"", ""method"": ""subtract"", ""params"": null, ""id"": 4}",
                     new Renor[]
                     {
-                        new Request(4, "subtract", null)
+                        new Request(4, "subtract", new JObject())
                     });
 
                 yield return (
@@ -96,7 +96,7 @@ public override IEnumerable<ValueTuple<string, Renor[]>> GetValues()
                     @"{""jsonrpc"": ""2.0"", ""method"": ""foobar"", ""params"": null}",
                     new Renor[]
                     {
-                        new Notification("foobar", null)
+                        new Notification("foobar", new JObject())
                     });
 
                 yield return (

test/Lsp.Tests/LspRequestRouterTests.cs

@@ -144,5 +144,24 @@ public async Task ShouldRouteToCorrect_Request_WithManyHandlers()
             await codeActionHandler.Received(1).Handle(Arg.Any<CodeActionParams>(), Arg.Any<CancellationToken>());
             await codeActionHandler2.Received(0).Handle(Arg.Any<CodeActionParams>(), Arg.Any<CancellationToken>());
         }
+
+        [Fact]
+        public async Task ShouldRouteTo_CorrectRequestWhenGivenNullParams()
+        {
+            var handler = Substitute.For<IShutdownHandler>();
+            handler
+                .Handle(Arg.Any<object>(), Arg.Any<CancellationToken>())
+                .Returns(Task.CompletedTask);
+
+            var collection = new HandlerCollection { handler };
+            var mediator = new LspRequestRouter(collection, _testLoggerFactory, _handlerMatcherCollection, new Serializer());
+
+            var id = Guid.NewGuid().ToString();
+            var request = new Request(id, GeneralNames.Shutdown, new JObject());
+
+            await mediator.RouteRequest(mediator.GetDescriptor(request), request);
+
+            await handler.Received(1).Handle(Arg.Any<object>(), Arg.Any<CancellationToken>());
+        }
     }
 }