public void FK_back_pointer_is_fixed_up_as_FK_is_added()
{
var entityType = new EntityType(typeof(Customer));
var property = entityType.AddProperty(Customer.IdProperty);
entityType.SetKey(property);
var foreignKey
= entityType.AddForeignKey(entityType.GetKey(), property);
Assert.Same(entityType, foreignKey.EntityType);
Assert.Same(entityType, property.EntityType);
entityType.RemoveForeignKey(foreignKey);
// Currently property is not removed when FK is removed
Assert.Empty(entityType.ForeignKeys);
Assert.Same(property, entityType.Properties.Single());
Assert.Same(entityType, foreignKey.EntityType); // TODO: Throw here?
Assert.Same(entityType, property.EntityType);
}