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

# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# 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.

"""Base classes for our unit tests.

Allows overriding of flags for use of fakes, and some black magic for
inline callbacks.

"""

import functools
import unittest

import nose.plugins.skip


class skip_test(object):
    """Decorator that skips a test."""
    # TODO(tr3buchet): remember forever what comstud did here
    def __init__(self, msg):
        self.message = msg

    def __call__(self, func):
        @functools.wraps(func)
        def _skipper(*args, **kw):
            """Wrapped skipper function."""
            raise nose.SkipTest(self.message)
        return _skipper


class skip_if(object):
    """Decorator that skips a test if condition is true."""
    def __init__(self, condition, msg):
        self.condition = condition
        self.message = msg

    def __call__(self, func):
        @functools.wraps(func)
        def _skipper(*args, **kw):
            """Wrapped skipper function."""
            if self.condition:
                raise nose.SkipTest(self.message)
            func(*args, **kw)
        return _skipper


class skip_unless(object):
    """Decorator that skips a test if condition is not true."""
    def __init__(self, condition, msg):
        self.condition = condition
        self.message = msg

    def __call__(self, func):
        @functools.wraps(func)
        def _skipper(*args, **kw):
            """Wrapped skipper function."""
            if not self.condition:
                raise nose.SkipTest(self.message)
            func(*args, **kw)
        return _skipper


def skip_if_fake(func):
    """Decorator that skips a test if running in fake mode."""
    def _skipper(*args, **kw):
        """Wrapped skipper function."""
        if FLAGS.fake_tests:
            raise unittest.SkipTest('Test cannot be run in fake mode')
        else:
            return func(*args, **kw)
    return _skipper