Hi Tomasz. I gave this some more thought throughout the day and here's a few other tasks that would be nicely suited for GSoC. Together with some tutorial and test expansions this should make for a pretty full summer.
Honestly expanding the tor controller interface (and the corresponding stem changes to take advantage of it) would be the most impactful for stem users, but these would still be nice capabilities to have...
* Remote descriptor fetching [1]. This would allow stem applications to query descriptors without piggybacking on a tor instance (a very handy capability to have).
* Support for parsing the tor man page. This is a capability that arm has [2], allowing it to show information about tor's configuration options in the editor panel. We'd want to snag arm's code, clean it up, then add lots 'o tests.
* Support for connection resolution [3]. This is another capability that arm has but stem lacks [4].
Cheers! -Damian
[1] https://trac.torproject.org/8257 [2] https://gitweb.torproject.org/arm.git/blob/HEAD:/src/util/torConfig.py [3] https://trac.torproject.org/7910 [4] https://gitweb.torproject.org/arm.git/blob/HEAD:/src/util/connections.py