Empty-pre-post cleanup deletes snapshots regardless of cleanup-algorithm setting

[tootea]

Unlike the NumberCleaner and TimelineCleaner, the EmptyPrePosCleaner class in client/cleanup.cc does not check the configured cleanup algorithm in calculate_candidates, so it will delete any empty pre/post pair regardless of the cleanup algorithm setting. However, the Cleanup Algorithms section of the Snapper Tutorial claims the following:

Unless you have a good reason to do otherwise, you should always specify the cleanup algorithm when creating a
snapshot, otherwise the snapshot will never be deleted unless you do it manually. You do this by adding the following
to your snapper commands:
--cleanup-algorithm <number|timeline|empty-pre-post>

And later in that section:

Because no cleanup-algorithm is specified, the snapshot will never be deleted automatically.

When I made manual pre and post snapshots without specifying --cleanup-algorithm, they still got deleted by the cleaner soon afterwards.

Is this a code bug (EmptyPrePostCleaner should ignore snapshots without a cleanup-algorithm) or a documentation bug? If the latter, I would also recommend stressing in the manual that hand-creating pre/post pairs is likely not be the best idea and people should stick to "single" for any snapshots they want to keep.

[aschnell]

This is a documentation bug.

Note that you can disable the empty-pre-post cleanup by setting EMPTY_PRE_POST_CLEANUP="no".