Fixed error handling of unhandeled mutation errors (#7101)

Author: michaelstaib

src/HotChocolate/Core/src/Types.Mutations/MutationConventionTypeInterceptor.cs

@@ -182,7 +182,7 @@ private static void ApplyResultMiddleware(ObjectFieldDefinition mutation)
 
     private void TryApplyInputConvention(
         IResolverCompiler resolverCompiler,
-        ObjectFieldDefinition mutation, 
+        ObjectFieldDefinition mutation,
         Options options)
     {
         if (mutation.Arguments.Count is 0)
@@ -208,7 +208,7 @@ private void TryApplyInputConvention(
                     mutation.SourceType,
                     mutation.ResolverType,
                     argumentNameMap);
-            
+
             TypeMemHelper.Return(argumentNameMap);
         }
 
@@ -250,7 +250,7 @@ private void TryApplyInputConvention(
                         argumentType,
                         Path.Root);
             }
-            
+
             resolverArguments.Add(
                 new ResolverArgument(
                     argument.Name,
@@ -637,7 +637,7 @@ static void CreateErrorDefinitions(
                         var definition = new ErrorDefinition(
                             errorType,
                             schemaType,
-                            obj => obj);
+                            _ => null);
                         tempErrors.Add(definition);
                     }
                 }
@@ -734,7 +734,7 @@ private static Options CreateErrorOptions(
         var registeredType = _typeInitializer.InitializeType(type);
         _typeInitializer.CompleteTypeName(registeredType);
 
-        if (registeredType.Type is ObjectType errorObject && 
+        if (registeredType.Type is ObjectType errorObject &&
             errorObject.RuntimeType != typeof(object))
         {
             foreach (var possibleInterface in _typeRegistry.Types)
@@ -757,7 +757,7 @@ private static Options CreateErrorOptions(
                 }
             }
         }
-        else if (registeredType.Type is ObjectType errorInterface && 
+        else if (registeredType.Type is ObjectType errorInterface &&
             errorInterface.RuntimeType != typeof(object))
         {
             foreach (var possibleInterface in _typeRegistry.Types)

src/HotChocolate/Core/test/Types.Mutations.Tests/ErrorMiddlewareTests.cs

@@ -306,6 +306,34 @@ private ValueTask<IRequestExecutor> BuildSchemaAsync(
         return builder.BuildRequestExecutorAsync();
     }
 
+    [Fact]
+    public async Task Throw_Unexpected_Exception()
+    {
+        var executor =
+            await new ServiceCollection()
+                .AddGraphQL()
+                .AddQueryType(d => d.Name("Query").Field("foo").Resolve("bar"))
+                .AddMutationType<Mutation>()
+                .AddMutationConventions()
+                .BuildRequestExecutorAsync();
+
+        var result = await executor.ExecuteAsync(
+            """
+            mutation {
+              createSomething(input: { success: false }) {
+                book {
+                  title
+                }
+                errors {
+                    __typename
+                }
+              }
+            }
+            """);
+
+        result.MatchSnapshot();
+    }
+
     public class CustomNullRef
     {
         public CustomNullRef(NullReferenceException exception)
@@ -432,4 +460,19 @@ public class Payload
     {
         public string Foo() => "Bar";
     }
+
+    public class Mutation
+    {
+        public MutationResult<Book, SomeError>  CreateSomething(bool success)
+        {
+            throw new Exception("Broken");
+        }
+    }
+
+    public record Book(string Title);
+
+    public class SomeError
+    {
+        public string Message => "Some error message";
+    }
 }

src/HotChocolate/Core/test/Types.Mutations.Tests/__snapshots__/ErrorMiddlewareTests.Throw_Unexpected_Exception.snap

@@ -0,0 +1,17 @@
+{
+  "errors": [
+    {
+      "message": "Unexpected Execution Error",
+      "locations": [
+        {
+          "line": 2,
+          "column": 3
+        }
+      ],
+      "path": [
+        "createSomething"
+      ]
+    }
+  ],
+  "data": null
+}