[Python-Dev] Keeping an eye on Travis CI, AppVeyor and buildbots: revert on regression

[Victor Stinner]

Hi,

I fixed a few tests which failed randomly. There are still a few, but
the most annoying have been fixed. I will continue to keep an eye on
our CIs: Travis CI, AppVeyor and buildbots. Sometimes, even when I
report a regression, the author doesn't fix the bug. But when a test
fails on Travis CI or AppVeyor, we cannot merge a pull request, so it
blocks our whole workflow.

I will restart the policy that I proposed last year: if a change
introduces a regression and I'm unable to fix it quickly (say in less
than 2 hours and the author isn't available), I will simply revert the
change. Please don't take it personally, the purpose is just to
unblock our workflow and be able to detect other regressions. It's
just an opportunity for the change author to fix the change without
the pressure of the broken CI.

Buildbots only send email notifications to buildbot-status at python.org
when the state changes from success (green) to failure (red). It's
much simpler for me to spot a regression when most buildbots are
green.

By the way, while miss-lington is really an amazing tool (thanks
Mariatta!!!), most core developers (including me!) forgot that 2 years
ago, the policy was to check if a change doesn't break buildbots
before backporting a change (well, 2 years ago we forward-ported
changes, but it's the same idea ;-)). Please remind that we only run
tests on Linux and Windows as pre-commit checks on GitHub pull
requests, whereas it's very common to spot bugs on buildbots thanks to
the diversity of platforms and architectures (and different
performance).

All buildbot builders can be watched at:
http://buildbot.python.org/all/#/builders

But I prefer to watch notifications on IRC (#python-dev on Freenode)
and the buildbot-status mailing list.

https://mail.python.org/mm3/mailman3/lists/buildbot-status.python.org/

--

Night gathers, AND NOW MY WATCH BEGINS.
IT SHALL NOT END UNTIL MY DEATH.
I shall take no wife, hold no lands, father no children.
I shall wear no crowns and win no glory.
I shall live and die at my post.
I am the sword in the darkness.
I am the watcher on the walls.
I am the fire that burns against cold, the light that brings the dawn,
the horn that wakes the sleepers, the shield that guards the realms of
men.
I pledge my life and honor to the Night's Watch, for this night and
all the nights to come.

Victor