# -*- coding: utf-8 -*-

# vim: tabstop=4 shiftwidth=4 softtabstop=4

#    Copyright (C) 2012 Yahoo! Inc. All Rights Reserved.
#
#    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.

import unittest2

from oslo.config import cfg

CONF = cfg.CONF


class TestCase(unittest2.TestCase):
    """Test case base class for all unit tests."""

    def setUp(self):
        """Run before each test method to initialize test environment."""
        super(TestCase, self).setUp()
        self.overriden = []
        self.addCleanup(self._clear_attrs)

    def tearDown(self):
        super(TestCase, self).tearDown()
        self._reset_flags()

    def _reset_flags(self):
        for k, group in self.overriden:
            CONF.clear_override(k, group=group)

    def _clear_attrs(self):
        # Delete attributes that don't start with _ so they don't pin
        # memory around unnecessarily for the duration of the test
        # suite
        for key in [k for k in self.__dict__.keys() if k[0] != '_']:
            del self.__dict__[key]

    def flags(self, **kw):
        """Override flag variables for a test."""
        group = kw.pop('group', None)
        for k, v in kw.iteritems():
            CONF.set_override(k, v, group)
            self.overriden.append((k, group))