具有覆盖“delete”方法的模型的Django test deleteview

我正在为包含多个deleteviews的django应用程序编写测试。我使用以下代码的变体测试所有DeleteView:

#Object exists to begin with
response = self.client.get(reverse('roldelete', kwargs={'pk': self.role.pk}))
self.assertEqual(response.status_code, 200)

#Object Can be deleted can be posted
response = self.client.post(reverse('roldelete', kwargs={'pk': self.role.pk}))
self.assertEqual(response.status_code, 302)

#Object is actually deleted
response = self.client.get(reverse('roldelete', kwargs={'pk': self.role.pk}))
self.assertEqual(response.status_code, 404)

#Query returns an empty result
self.assertFalse(Role.objects.filter(pk=self.role.pk).exists())

所有这些都很好,但是,在我的一个模型中,我覆盖了默认的“delete”方法。基本上,每次我删除“TenantPurchase”对象时,我都想检查是否存在链接的“PurchaseRequest”对象,并将其删除。为此,我在TenantPurchase模型中编写了以下代码:

def delete(self, *args, **kwargs):
    try:

        purchase_user = self.user
        purchase_arrangement_period = self.item

        #Import here to avoid circular import
        from arrangement.models import ArrangementBuyRequest

        linked_buy_request = ArrangementBuyRequest.objects.filter(
            user=purchase_user,
            arrangement_period=purchase_arrangement_period) \
            .order_by('request_date').last()

        linked_buy_request.delete()
    except (ArrangementBuyRequest.DoesNotExist, AttributeError) as e:
        pass

    super(TenantPurchase, self).delete(*args, **kwargs)

然而,我对这个模型的所有单元测试都失败了。 它通过了前三个测试(assert 200、assert 302、assert 404)

self.assertFalse(
        TenantPurchase.objects.filter(tenant=self.tenant, user=self.user, item_id=self.period.pk).exists())


Traceback (most recent call last):
(...), line 105, in test_linked_request_deleted

self.assertFalse(ArrangementBuyRequest.objects.filter(user=self.user,         arrangement_period=self.period).exists())
AssertionError: True is not false

链接的购买请求同上:

# Check if the related buyrequest has been deleted as well
    self.assertFalse(ArrangementBuyRequest.objects.filter(user=self.user, arrangement_period=self.period).exists())

Traceback (most recent call last):
(...), line 80, in test_tenant_purchase_deleted
TenantPurchase.objects.filter(tenant=self.tenant, user=self.user, item_id=self.period.pk).exists())
AssertionError: True is not false

由于这种情况与所有其他(通过的)测试之间的唯一区别是模型中覆盖的“delete”方法,因此问题可能来自该部分(可能在测试中没有正确加载) 但是我找不到导致测试失败的错误。在我们的开发服务器上一切都很好,这对我们没有帮助,很难找出错误。

有人知道我错过了什么吗?