'Verify that if problem display name is not provided then a default name is used.'

@ddt.data('', '            ')
def test_problem_no_display_name(self, display_name):

    module = CapaFactory.create(display_name=display_name)
    module.get_problem_html()
    (render_args, _) = module.system.render_template.call_args
    context = render_args[1]
    self.assertEqual(context['problem']['name'], module.location.block_type)
