'Assigning an unsaved object to GenericForeignKey should raise an
exception on model.save().'

def test_unsaved_instance_on_generic_foreign_key(self):

    quartz = Mineral(name='Quartz', hardness=7)
    with self.assertRaises(IntegrityError):
        TaggedItem.objects.create(tag='shiny', content_object=quartz)
