A user reported that forget --keep-tag is not clearly defined. The manual says:

--keep-tag keep all snapshots which have all tags specified by this option (can be specified multiple times).

The help text is:

--keep-tag tag        keep snapshots with this tag (can be specified multiple times)

At the moment it's implemented this way: When just one tag to keep is specified (--keep-tag foo) restic won't touch any snapshots that have tag foo. For multiple tags to keep (e.g. --keep-tag foo --keep-tag bar) restic won't remove snapshots which have both tag foo and tag bar, but can forget snapshots which just have tag foo.

The manual states this (more or less clearly), but the help text is not clear.

I'd like to propose the following change: --keep-tag foo will work as is. --keep-tag foo,bar instructs restic to keep all snapshots that have both foo and bar. --keep-tag foo --keep-tag bar will not touch any snapshots that have either foo or bar set.

@middelink What do you think?