'If the ``attach_volume`` function raises an unexpected exception, it is
passed through.'

@given(device=device_path)
def test_unexpected_attach_exception(self, device):

    def attach_volume(blockdevice_id, compute_id, device):
        raise CustomException('Fake    failure    generated    by    test')
    self.assertRaises(CustomException, _attach_volume_and_wait_for_device, volume=self.volume, attach_to=self.compute_id, attach_volume=attach_volume, detach_volume=(lambda *a, **kw: None), device=device, blockdevices=[])
