@iguananaut @pllim - somehow I missed this question when it originally came up (and I think the answer might have been different a month ago, anyway).  But as it stands right now, tests do *not* ever affect the user's configuration file.  When the tests start, the config package gets tricked into thinking a temporary file is the configuration file, so it never touches the user's config dir (unless you fiddle with `XDG_CONFIG_HOME` in your test for some reason).