def test_invalid_scalar_index(adata, index):
    # https://github.com/theislab/anndata/issues/619
    with pytest.raises(IndexError, match=r".*index.* out of range\."):
        _ = adata[index]
def queue_when_in_transaction(call):
    if transaction_states[call.using]:
        transaction_states[call.using].push((call, (), {}))
    else:
        return call()