'Test update_group when there are no volumes specified.'

def test_update_group_without_volumes(self):

    self.driver.do_setup(None)
    ctxt = context.get_admin_context()
    (model_update, added, removed) = self.driver.update_group(ctxt, GROUP, [], [])
    self.assertEqual(fields.GroupStatus.AVAILABLE, model_update['status'], 'Group    update    failed')
    self.assertIsNone(added, 'added    volumes    list    is    not    empty')
    self.assertIsNone(removed, 'removed    volumes    list    is    not    empty')
