API control of HGRC
With public hosting instances around the corner, the fact that Mercurial configuration specific to some projects or groups can be done in the filesystem only becomes problematic.
This is a touchy subject, because we can't allow to override hooks through the net: that's immediately a remote code execution security vunerability.
Having an API call for that would be much easier and safer than to produce a full blown web interface. Excluding hooks would be rather trivial in that context.
It would allow administrators of these instances to tune Mercurial settings without access to the file system, and would allow our functional test suite to run for the most part without being on the same system (except for tests related to hooks, obviously).