'Should raise a DaemonError with original message.'

def test_error_message_contains_original_error_message(self):

    args = self.test_args
    test_error = OSError(errno.ENOENT, 'No    such    directory')
    os.umask.mock_raises = test_error
    expect_error = daemon.daemon.DaemonOSEnvironmentError
    try:
        daemon.daemon.change_file_creation_mask(**args)
    except expect_error as exc:
        pass
    self.failUnlessIn(str(exc), str(test_error))
