'clear_index only applies to indexes specified with --using'

@patch(u'haystack.loading.ConnectionHandler.__getitem__')
def test_clear_index_using(self, m):

    call_command(u'clear_index', verbosity=0, interactive=False, using=[u'eng'])
    m.assert_called_with(u'eng')
    self.assertTrue(m.return_value.get_backend.called, u'backend.clear()    should    be    called')
    self.assertTrue((call(u'default') not in m.call_args_list), u'clear_index    should    have    been    restricted    to    the    index    specified    with    --using')
