'``list_volumes`` returns both attached and unattached
``BlockDeviceVolume``s.'

def test_list_attached_and_unattached(self):

    new_volume1 = self.api.create_volume(dataset_id=uuid4(), size=self.minimum_allocatable_size)
    new_volume2 = self.api.create_volume(dataset_id=uuid4(), size=self.minimum_allocatable_size)
    attached_volume = self.api.attach_volume(blockdevice_id=new_volume2.blockdevice_id, attach_to=self.this_node)
    self.repeat_until_consistent((lambda : self.assertItemsEqual([new_volume1, attached_volume], self.api.list_volumes())))
