def test_datetime_change(self):
tm = TestModel()
# initial state shouldn't be dirty
self.assertEqual(tm.get_dirty_fields(), {})
# changing values should flag them as dirty
dt = datetime(2013, 1, 1)
tm.created = dt
self.assertEqual(tm.get_dirty_fields(), {
'created': None
})
# resetting them to original values should unflag
tm.created = None
self.assertEqual(tm.get_dirty_fields(), {})
