Comment 5 for bug 1376423

I forgot to comment about creating a new user: This is the difference between "the test needs root privileges and is even more invasive to the system" and "the test can run with normal user privileges and does not leave permanent clutter behind". I. e. creating a new user introduces the obligation to ensure that it always gets removed again, even if the test or test runner fails in the middle of the run.

Also, doing so doesn't actually help at all with the main issue here to centralize the knowledge how to start an UAL session: We need to do that regardless of whether this happens for a "real" user with a temp $HOME or for a temp user.

So in summary, creating temp users only makes the test bed setup more complicated, less convenient, and potentially harmful (due to requiring root privs) without gaining much.