[Buildbot-devel] testFallback2 failing for me

[Brian Warner]

> /usr/local/src/buildbot-0.7.4$ buildbot --version
> Buildbot version: 0.7.4
> Twisted version: 1.3.0rc1
> 
> ERROR: testFallback2 (buildbot.test.test_slaves.Slave)

> Failure: [Failure instance: Traceback: twisted.trial.unittest.FailTest, 2 != 1

> Any ideas?  Is my version of Twisted just too old?

Yeah, basically. There is a race condition that gets triggered by Twisted 1.3
fairly frequently, and some changes went into Twisted 2.0 and later which
generally make it go away. (it involves a __del__ handler which triggers a
lot of activity at a funny time). As far as I can tell it doesn't cause
problems for normal operations, but it does cause unit test failures over
half of the times that I run it, more on some machines than others.

That said, the next release (0.7.5) will probably not support Twisted-1.3.0
(nor python-2.2). I've been using python-2.3 features like sets and "substr"
in "str", and I can clean up some ugly code by not providing backwards
compatibility for some old Twisted-1.3 idioms. I no longer have
metabuildslaves for python-2.2, and the twisted-1.3 builders are showing
errors like the one you saw on a consistent basis.

So 0.7.5 "might work if you're lucky" on either of these platforms, but there
are no promises. Upgrading now would be a splendid idea :).

cheers,
 -Brian