def test_assign_to_value_without_pk(self):
record = DummyModel()
expected = "Cannot assign DummyRelated without pk to DummyModel.related"
with self.assertRaisesMessage(ValueError, expected):
record.related = DummyRelated()
def test_assign_to_bad_type_value(self):
record = DummyModel()
expected = "Cannot assign 42: " "DummyModel.related must be a DummyRelated instance"
with self.assertRaisesMessage(ValueError, expected):
record.related = 42