Test failure if user is not in a second usergroup (1.5.3.rc1, Fedora 41)

[buhtz]

First reported in #1911 by @hannes101 and moved into its own issue here.

The test TestRestorePathInfo.test_change_group failes because the testing user is not member in a second usergroup.
This happens in Fedora 41 build environments which use mock (chroot) to isolate the build.

____________________ TestRestorePathInfo.test_change_group _____________________
self = <test.test_snapshots.TestRestorePathInfo testMethod=test_change_group>
    def test_change_group(self):
>       newGroup = [x for x in GROUPS if x != CURRENTGROUP][0]
E       IndexError: list index out of range
test/test_snapshots.py:608: IndexError

The constant CURRENTGROUP is created in common/test/constants.py:

import grp
import os
import pwd


CURRENTUID = os.geteuid()
CURRENTUSER = pwd.getpwuid(CURRENTUID).pw_name
CURRENTGID = os.getegid()
CURRENTGROUP = grp.getgrgid(CURRENTGID).gr_name
CURRENTUID = os.geteuid()
CURRENTGID = os.getegid()

GROUPS is created in common/test/test_snapshots.py:

GROUPS = [i.gr_name for i in grp.getgrall() if CURRENTUSER in i.gr_mem]

About a possible solution:

1. I could skip the test if the len(GROUPS) < 2.
2. But I would prefer if you could modify your build environment somehow. Might this be possible?
3. I could raise an Exception if len(GROUPS) < 2 and instruct to add the user to a second group. It would be an instruction for distro maintainers.

It was recommended to use solution 1.