python-openstackclient/tests/test_clientmanager_clientcache.py

#   Copyright 2012-2013 OpenStack, LLC.
#
#   Licensed under the Apache License, Version 2.0 (the "License"); you may
#   not use this file except in compliance with the License. You may obtain
#   a copy of the License at
#
#        http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#   WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#   License for the specific language governing permissions and limitations
#   under the License.
#

from openstackclient.common import clientmanager


def factory(inst):
    return object()


class Container(object):

    attr = clientmanager.ClientCache(factory)

    def init_token(self):
        return


def test_singleton():
    # Verify that the ClientCache descriptor only
    # invokes the factory one time and always
    # returns the same value after that.
    c = Container()
    assert c.attr is c.attr