I'm trying to unit test my update forms and views. I'm using Django Crispy Forms for both my Create and Update Forms. UpdateForm inherits CreateForm and makes a small change to the submit button text. The CreateView and UpdateView are very similar. They have the same model, template, and success_url. They differ in that they use their respective forms, and CreateView inherits django.views.generic.CreateView, and UpdateView inherits django.views.generic.edit.UpdateView.

The website works fine. I can create and edit an object without a problem. However, my second test shown below fails. How do I test my UpdateForm?

Any help would be appreciated. Thanks.

This test passes:

class CreateFormTest(TestCase):def setUp(self):self.valid_data = {'x': 'foo','y': 'bar',}def test_create_form_valid(self):""" Test CreateForm with valid data """form = CreateForm(data=self.valid_data)self.assertTrue(form.is_valid())obj = form.save()self.assertEqual(obj.x, self.valid_data['x'])

This test fails:

class UpdateFormTest(TestCase):def setUp(self):self.obj = Factories.create_obj()  # Creates the objectdef test_update_form_valid(self):""" Test UpdateForm with valid data """valid_data = model_to_dict(self.obj)valid_data['x'] = 'new'form = UpdateForm(valid_data)self.assertTrue(form.is_valid())case = form.save()self.assertEqual(case.defendant, self.valid_data['defendant']

When pre-populating a ModelForm with an object that has already been created you can use the instance keyword argument to pass the object to the form.

form = SomeForm(instance=my_obj)

This can be done in a test, such as in the OP< or in a view to edit an object that has already been created. When calling save() the existing object will updated instead of creating a new one.