public void TestSetByDerived()
        {
            NamedObjectSave nos = mDerivedEntity.NamedObjects.FirstOrDefault(item => item.FieldName == "SpriteInstance");

            bool shouldCreate =
                ElementRuntime.ShouldElementRuntimeBeCreatedForNos(nos, mDerivedEntity);

            if (!shouldCreate)
            {
                throw new Exception("NOS's which are defined by base, but their base has SetByDerived should be created.");
            }



            if (mDerivedElementRuntime.ContainedElements.FirstOrDefault(item => item.Name == "SpriteInstance") == null)
            {
                throw new Exception("Objects defined in base and SetByDerived should be created, but are not.");
            }

            // Verify that only 1 AARect has been made
            int count = 0;

            foreach (var item in mDerivedElementRuntime.ContainedElements.Where(item => item.Name == "RectInstance"))
            {
                count++;
            }
            if (count != 1)
            {
                throw new Exception("Only one rectangle should be created, but it looks like more are made");
            }
        }