Test groupadd and groupmod -U option with empty user list

[ikerexxe]

Tests: #1422

[alejandro-colomar]

Thanks! Could you please remove the bugfix patches? That should show in the CI the failures, which will make sure that the tests actually do their job.

[alejandro-colomar]

LGTM. Thanks! @hallyn , would you mind merging first this PR, and then mine?

[ikerexxe]

Thanks! Could you please remove the bugfix patches? That should show in the CI the failures, which will make sure that the tests actually do their job.

Done!

[alejandro-colomar]

Please rebase.

[ikerexxe]

Done

[hallyn]

Do you mind adding a test which creates three users, adds them to the new group, then uses usermod -U to change the group to only have two of the users?

[alejandro-colomar]

Do you mind adding a test which creates three users, adds them to the new group, then uses usermod -U to change the group to only have two of the users?

That should go in a separate PR, right?

[hallyn]

Do you mind adding a test which creates three users, adds them to the new group, then uses usermod -U to change the group to only have two of the users?

That should go in a separate PR, right?

Well, a separate commit. The PR could just be "usermod -U tests".

But ok.

[ikerexxe]

Do you mind adding a test which creates three users, adds them to the new group, then uses usermod -U to change the group to only have two of the users?

Done, but I'm assuming you meant groupmod -U and not usermod -U. The latter checks a different thing

[hallyn]

Hm, do you know what's up with the failing tests?

[ikerexxe]

This PR doesn't include the fixes from #1422, thus it makes sense that tests are failing