def test_add_already_added(self):
        prio_set_list = event._PrioritizedSetList()
        obj = object()
        prio_set_list.add(0, obj)

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(0, obj)
        excinfo.match(r"has already been added")

        with pytest.raises(ValueError) as excinfo:
            prio_set_list.add(1, obj)
        excinfo.match(r"has already been added")
def check_url_error_message(value):
    try:
        inputs.url(value)
        assert False, u"inputs.url({0}) should raise an exception".format(value)
    except ValueError as e:
        assert_equal(six.text_type(e),
                     (u"{0} is not a valid URL. Did you mean: http://{0}".format(value)))