Additional fix OnReturn hook (#938)

* Additional fix OnReturn hook

Author: maurei

src/Examples/JsonApiDotNetCoreExample/Definitions/TodoItemHooksDefinition.cs

@@ -29,5 +29,10 @@ public override void BeforeImplicitUpdateRelationship(IRelationshipsDictionary<T
             List<TodoItem> todos = resourcesByRelationship.GetByRelationship<Person>().SelectMany(kvp => kvp.Value).ToList();
             DisallowLocked(todos);
         }
+
+        public override IEnumerable<TodoItem> OnReturn(HashSet<TodoItem> resources, ResourcePipeline pipeline)
+        {
+            return resources.Where(t => t.Description != "This should not be included");
+        }
     }
 }

src/JsonApiDotNetCore/Hooks/Internal/ResourceHookExecutorFacade.cs

@@ -122,7 +122,7 @@ public object OnReturnRelationship(object resourceOrResources)
             if (resourceOrResources is IEnumerable)
             {
                 dynamic resources = resourceOrResources;
-                return _resourceHookExecutor.OnReturn(resources, ResourcePipeline.GetRelationship).ToArray();
+                return Enumerable.ToArray(_resourceHookExecutor.OnReturn(resources, ResourcePipeline.GetRelationship));
             }
 
             if (resourceOrResources is IIdentifiable)

test/JsonApiDotNetCoreExampleTests/IntegrationTests/ResourceHooks/ResourceHookTests.cs

@@ -202,6 +202,31 @@ await _testContext.RunOnDatabaseAsync(async dbContext =>
             responseDocument.Should().NotContain(toBeExcluded);
         }
 
+        [Fact]
+        public async Task Can_hide_secondary_resource_from_ToOne_relationship_using_OnReturn_hook()
+        {
+            // Arrange
+            var person = _fakers.Person.Generate();
+            person.Passport = new Passport {IsLocked = true};
+
+            await _testContext.RunOnDatabaseAsync(async dbContext =>
+            {
+                dbContext.People.Add(person);
+                await dbContext.SaveChangesAsync();
+            });
+
+            var route = $"/api/v1/people/{person.Id}/passport";
+
+            // Act
+            var (httpResponse, responseDocument) = await _testContext.ExecuteGetAsync<Document>(route);
+
+            // Assert
+            httpResponse.Should().HaveStatusCode(HttpStatusCode.OK);
+
+            responseDocument.Data.Should().BeNull();
+        }
+
+
         [Fact]
         public async Task Can_hide_secondary_resource_from_ToMany_List_relationship_using_OnReturn_hook()
         {
@@ -233,24 +258,27 @@ await _testContext.RunOnDatabaseAsync(async dbContext =>
         public async Task Can_hide_secondary_resource_from_ToMany_Set_relationship_using_OnReturn_hook()
         {
             // Arrange
+            string toBeExcluded = "This should not be included";
+
             var person = _fakers.Person.Generate();
-            person.Passport = new Passport {IsLocked = true};
+            person.TodoItems = _fakers.TodoItem.Generate(3).ToHashSet();
+            person.TodoItems.First().Description = toBeExcluded;
 
             await _testContext.RunOnDatabaseAsync(async dbContext =>
             {
                 dbContext.People.Add(person);
                 await dbContext.SaveChangesAsync();
             });
 
-            var route = $"/api/v1/people/{person.Id}/passport";
+            var route = $"/api/v1/people/{person.Id}/todoItems";
 
             // Act
-            var (httpResponse, responseDocument) = await _testContext.ExecuteGetAsync<Document>(route);
+            var (httpResponse, responseDocument) = await _testContext.ExecuteGetAsync<string>(route);
 
             // Assert
             httpResponse.Should().HaveStatusCode(HttpStatusCode.OK);
 
-            responseDocument.Data.Should().BeNull();
+            responseDocument.Should().NotContain(toBeExcluded);
         }
 
         [Fact]