swh_storage = <swh.storage.retry.RetryingProxyStorage object at 0x7fdefc1c72e8> sample_data = <swh.storage.tests.storage_data.StorageData object at 0x7fdefc1c7438> def test_retrying_proxy_storage_directory_add(swh_storage, sample_data): """Standard directory_add works as before """ sample_dir = sample_data.directory > directory = swh_storage.directory_get_random() # no directory .tox/py3/lib/python3.7/site-packages/swh/storage/tests/test_retry.py:564: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .tox/py3/lib/python3.7/site-packages/swh/storage/in_memory.py:458: in directory_get_random return random.choice(list(self._directories)) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ self = <random.Random object at 0x1946b28>, seq = [] def choice(self, seq): """Choose a random element from a non-empty sequence.""" try: i = self._randbelow(len(seq)) except ValueError: > raise IndexError('Cannot choose from an empty sequence') from None E IndexError: Cannot choose from an empty sequence /usr/lib/python3.7/random.py:261: IndexError