如何针对类视图使用assertEqual(resolve())？Django URL测试报错求助

问题重现 #

测试类视图URL解析时出现断言错误，相关信息如下：

初始错误信息 #

self.assertEqual(resolve(url).func, BookList.name)
AssertionError: <function View.as_view..view at 0x0000025699398360> != 'BookList'

相关代码 #

views.py

class BookList(generics.ListAPIView):
    """Retrive book list"""
    queryset = models.Book.objects.all()
    serializer_class = book_serializer.BookSerializer

urls.py

path('', views.BookList.as_view(), name='book-list'),

初始测试代码（test.py）

from django.test import SimpleTestCase
from django.urls import reverse, resolve
from book.views import BookList

class TestUrls(SimpleTestCase):
    def test_list_url_is_resolved(self):
        url = reverse('book-list')
        print(resolve(url))
        self.assertEqual(resolve(url).func, BookList.__name__)

尝试过的错误写法及对应报错 #

1. 写法一：

class TestUrls(SimpleTestCase):
    def test_list_url_is_resolved(self):
        url = reverse('book-list')
        print(resolve(url))
        self.assertEqual(resolve(url).func.__name__, BookList.as_view())

报错：

self.assertEqual(resolve(url).func.name, BookList.as_view())
AssertionError: 'view' != <function View.as_view..view at 0x000001FA9E7320C0>

2. 写法二：

def test_list_url_is_resolved(self):
        url = reverse('book-list')
        print(resolve(url))
        self.assertEqual(resolve(url).func, BookList.as_view())

报错：

self.assertEqual(resolve(url).func, BookList.as_view())
AssertionError: <function View.as_view..view at 0x000002C666D48360> != <function View.as_view..view at 0x000002C666D120C0>

正确测试方法 #

有两种可靠的方式验证类视图URL解析：

方法一：直接验证视图类 #

as_view()生成的包装函数带有view_class属性，指向原类视图，直接对比即可：

from django.test import SimpleTestCase
from django.urls import reverse, resolve
from book.views import BookList

class TestUrls(SimpleTestCase):
    def test_list_url_is_resolved(self):
        url = reverse('book-list')
        self.assertEqual(resolve(url).func.view_class, BookList)

方法二：验证类名称字符串 #

如果需要对比类名字符串，取func.view_class.__name__与类名对比：

from django.test import SimpleTestCase
from django.urls import reverse, resolve
from book.views import BookList

class TestUrls(SimpleTestCase):
    def test_list_url_is_resolved(self):
        url = reverse('book-list')
        self.assertEqual(resolve(url).func.view_class.__name__, BookList.__name__)

错误原因分析 #

• 初始错误：resolve(url).func是as_view()生成的包装函数对象，BookList.__name__是字符串，类型不匹配无法相等。
• 写法一错误：将函数名字符串与as_view()生成的函数对象对比，且func.__name__返回的是包装函数名view，不是类视图名称。
• 写法二错误：每次调用BookList.as_view()都会生成新的函数实例，两次调用的函数内存地址不同，无法直接相等。

内容的提问来源于stack exchange，提问作者Lucian