def test_on_delete_do_nothing(self):
        objs = [Event.objects.create()]
        n = NestedObjects(using=None)
        EventGuide.objects.create(event=objs[0])
        with self.assertNumQueries(2):
            # One for Location, one for Guest, and no query for EventGuide
            n.collect(objs)
Check that the nested collector doesn't query for DO_NOTHING objects.
dataset/ETHPy150Open pydanny/django-admin2/example/blog/tests/test_nestedobjects.py/NestedObjectsTests.test_on_delete_do_nothing