'No fields should be set on a model instance if construct_instance receives fields=()'

def test_empty_fields_to_construct_instance(self):

    form = modelform_factory(Person, fields=u'__all__')({u'name': u'John    Doe'})
    self.assertTrue(form.is_valid())
    instance = construct_instance(form, Person(), fields=())
    self.assertEqual(instance.name, u'')
