Re: How to notice when my change breaks something

["Björn Höfling" <bjoern.hoefling@bjoernhoefling.de>]

Hi Mark,

On Sun, 11 Feb 2018 17:35:43 -0500
Mark H Weaver <mhw@netris.org> wrote:

> Hi Chris,
> 
> Chris Marusich <cmmarusich@gmail.com> writes:
> 
> > How do you notice when a change breaks something else?  You so
> > frequently notice these things, it almost seems like you're
> > omniscient!
> >
> > Do you have an automated mechanism for doing this, or are you
> > manually checking things frequently?  
> 
> I regularly check Hydra for newly failed packages.  To see the most
> recent evaluations, visit <https://hydra.gnu.org/evals>.  Each
> evaluation corresponds to a commit of Guix's git repo.  You can
> compare two evaluations with URLs of the form
> <https://hydra.gnu.org/eval/109907?compare=109906>, which will compare
> evaluation 109907 to the previous evaluation 109906.  It is also often
> useful to compare to a slightly older evaluation, especially one with
> an unusually low number of failures, e.g.
> <https://hydra.gnu.org/eval/109907?compare=109896> where 109896 was
> the most recent evaluation of 'master' with fewer than 1900 failures.
> 
> Note that hydra.gnu.org is not sufficiently powerful for the work it
> is currently doing, so it often takes on the order of several
> *minutes* for the above URLs to load, and sometimes the Nginx
> front-end will time-out before that happens.  Our new build farm is
> vastly more powerful, but its web interface is currently quite
> rudimentary and not yet sufficient for the kind of monitoring I do on
> Hydra.
> 
> Hope this helps.
> 
>        Mark


Yes, that definitely helped me too.

I have a follow-up question: This day I realized that teeworlds broke
on core-updates due to a freetype update (see
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=30518).

Now I thought: Is it possible to download the whole list of
(directly) breaking packages from Hydra? If so, I could fold-packages
through them and filter out those that also have freetype as a
dependency and probably fix them with a one-liner. Is there any
download/API functionality for Hydra?

Björn