基于类的视图中的模拟表单不使用 MagicMock

我一直在努力模拟表单类以在基于类的视图中替换它的实例。但看起来是这样，因为表单位于类属性中，所以会发生这种情况before我用我的模拟替换了表单类。例证：

应用程序/views.py

from app.forms import SomeForm  # For some reason, this _is_ my mock...

class SomeViewClass(View):
    form = SomeForm  # ... while this is the _real_ SomeForm

    def post(self, request):
        form = self.form(request.POST, request.FILES)

        # Hacked around with pdb here
        # (Pdb) self.form = SomeForm <-- Force the mock into the object
        # (Pdb) form = self.form(request.POST, request.FILES)
        # (Pdb) form.is_valid() is now True
        # (Pdb) continue <--- Test finishes, and asserts are OK.

        if form.is_valid():  # This fails, as I'm running the real code
            # code, code, code

应用程序/测试/test_views.py

from mock import MagicMock, patch

from django.tests import Client, TestCase


@patch('app.views.SomeForm')
    def test_post_valid_form_should_pass(self, mocked_form_class):
        """ Replacing SomeForm in SomeViewClass to pas the is_valid test
        """
        form_instance = MagicMock(spec=SomeForm())
        form_instance.is_valid.return_value = True
        mocked_form_class.return_value = form_instance

        self.client.login(**self.credentials)
        # code, code, code

正如您在插入的评论中看到的app/views.py，我强行重装了self.form并重新定义变量form使用 pdb，这使我的测试通过了。

似乎由于某种原因，SomeViewClass在我开始修补之前已[注册，实例化，...]SomeForm。对此有什么想法吗？

问题是视图已经被 Django 加载并且form字段已经定义并指向SomeForm 生产 class.

正如 @DanielRoseman 和 @foxyblue 在他们的评论中指出的那样，可以直接修补类中的字段。而实际上SO 上已经有答案了 https://stackoverflow.com/a/42180559/2441358。正如所指出的，可以使用patch.object 修补类的成员 https://docs.python.org/3/library/unittest.mock.html#patch-object（在我看来，这是最好的解决方案，因为它更明确，并且不太容易出现拼写错误）

测试更正：

With patch

@patch('app.views.SomeView.form', autospec=SomeForm)
    def test_post_valid_form_should_pass(self, mocked_form_class):
        """ Replacing SomeForm in SomeViewClass.form to pass the is_valid test """
        mocked_form_class.is_valid.return_value = True

        self.client.login(**self.credentials)
        # code, code, code

With patch.object

@patch.object(SomeView, 'form', autospec=SomeForm)
    def test_post_valid_form_should_pass(self, mocked_form_class):
        """ Replacing SomeForm in SomeViewClass.form to pass the is_valid test """
        mocked_form_class.is_valid.return_value = True

        self.client.login(**self.credentials)
        # code, code, code