外键TestCase

Question

我正试图对模型进行测试，并且遇到了一些有外键的测试。当我试着用setUp制作卡片时，我无法做到。我不明白为什么。属性category的预期值是int。无论是category，category.id，还是“测试类别”工作。

代码：models.py

class Category(models.Model):
    category_name = models.CharField(max_length=32)


class Card(models.Model):
    category = models.ForeignKey(Category, on_delete=models.CASCADE)
    question = models.CharField(max_length=255)
    answer = models.TextField()
    slug = models.SlugField()

test_models.py

class CardTestCase(TestCase):
    def setUp(self) -> None:
        category = Category.objects.create(category_name='Test Category')
        Card.objects.create(category=category,
                            question='Hello?',
                            answer='Hello!',
                            slug='slug'
                            )

    def test_card_exists(self):
        category = Category.objects.get(category_name='Test Category')
L29        card = Card.objects.get(category=category.id,
                                question='Hello?',
                                answer='Hello!',
                                slug='slug'
                                )

错误：

line 29, in test_card_exists  
    card = Card.objects.get(category=category.id,
django_cards.cards.models.Card.DoesNotExist: Card matching query does not exist.

Answer 1

与其提供category.id，不如只提供类别对象本身。

card = Card.objects.filter(category=category,
                                question='Hello?',
                                answer='Hello!',
                                slug='slug'
                                )

我使用的是过滤器，而不是get，以防给定参数有多个对象。