Ditto - unit-test to explore how mapping polymorphic collections might work

PolymorphicCollectionMappingTests.cs

using System;
using System.Collections.Generic;
using System.Linq;
using NUnit.Framework;

namespace Our.Umbraco.Ditto.Tests
{
    [TestFixture]
    public class PolymorphicCollectionMappingTests
    {
        [AttributeUsage(AttributeTargets.Class, Inherited = false, AllowMultiple = false)]
        public sealed class DittoDocTypeAttribute : Attribute
        {
            public DittoDocTypeAttribute(string alias = null)
            { }
        }

        public interface IModel
        { }

        [DittoDocType]
        public class MyModel : IModel
        { }

        [DittoDocType("myDocType2")]
        public class MyModel2 : IModel
        { }

        [Test]
        public void Polymorphic_Collection_Maps()
        {
            var nodes = new List<Mocks.PublishedContentMock>()
            {
                new Mocks.PublishedContentMock { Id = 1111, DocumentTypeAlias = "myDocType1" },
                new Mocks.PublishedContentMock { Id = 2222, DocumentTypeAlias = "myDocType2" },
                new Mocks.PublishedContentMock { Id = 3333, DocumentTypeAlias = "myDocType3" },
            };

            var items = nodes.As<IEnumerable<IModel>>();

            Assert.That(items, Is.Not.Null);
            Assert.That(items.Count(), Is.EqualTo(3));

            CollectionAssert.AllItemsAreInstancesOfType(items, typeof(IModel));

            Assert.That(items.First(), Is.TypeOf<MyModel>());
            Assert.That(items.Skip(1).First(), Is.TypeOf<MyModel2>());
            Assert.That(items.Skip(2).First(), Is.TypeOf<MyModel>());
        }
    }
}