test(extensibility): verify users can serialize custom errors

Author: jaredcnance

test/JsonApiDotNetCoreExampleTests/Acceptance/Extensibility/CustomErrorTests.cs

@@ -0,0 +1,53 @@
+using DotNetCoreDocs;
+using JsonApiDotNetCoreExample;
+using DotNetCoreDocs.Writers;
+using Newtonsoft.Json;
+using JsonApiDotNetCore.Internal;
+using JsonApiDotNetCore.Serialization;
+using Xunit;
+using System.Diagnostics;
+
+namespace JsonApiDotNetCoreExampleTests.Acceptance.Extensibility
+{
+    public class CustomErrorTests
+    {
+        [Fact]
+        public void Can_Return_Custom_Error_Types()
+        {
+            // while(!Debugger.IsAttached) { bool stop = false; }
+
+            // arrange
+            var error = new CustomError("507", "title", "detail", "custom");
+            var errorCollection = new ErrorCollection();
+            errorCollection.Add(error);
+
+            var expectedJson = JsonConvert.SerializeObject(new {
+                errors = new dynamic[] {
+                    new { 
+                        myCustomProperty = "custom",
+                        title = "title",
+                        detail = "detail",
+                        status = "507"                        
+                    }
+                }
+            });
+
+            // act
+            var result = new JsonApiSerializer(null, null, null)
+                .Serialize(errorCollection);
+
+            // assert
+            Assert.Equal(expectedJson, result);
+
+        }
+
+        class CustomError : Error {
+            public CustomError(string status, string title, string detail, string myProp)
+            : base(status, title, detail)
+            {
+                MyCustomProperty = myProp;
+            }
+            public string MyCustomProperty { get; set; }
+        }
+    }
+}