Code review comment for lp:~eugenesan/ppa-purge/trunk

Thanks, that looks very good. Note that we don't use {} around variables other places unless it is needed, and it is not needed on this lesspipe command either.

The empty repo is something that ppa-purge can not handle. It is a bad PPA which removes packages that have been published :) The hacky logic in ppa-purge uses the existing packages in the PPA to figure out which packages need to be reverted. So if there are no packages there, ppa-purge should fail in my opinion. All it can do in this case is removing the PPA from the sources.list, but the user should rather use Software Sources for this. Well, somebody should write apt-delete-repository to pair with apt-add-repository :) Then we could also just call that internally when things are ok, and bail out and tell the user to just use that when the PPA is empty, and not give the user the impression that ppa-purge did its job, which is mainly the reverting packages part.

There are tricks like "aptitude search '~i!~Oubuntu' to find packages that are not installed from Ubuntu repositories, but I don't know a way to find packages installed from a PPA.