Poor old bug.

Just being bitten from it today, while trying to package pyftpdlib on the openSUSE build service, which creates a clean reproducible build environment for all packages, and testing fails.

Part of the game: openssl 1.0.1k, Python 2.7.8

https://build.opensuse.org/package/show/home:frispete:python/python-pyftpdlib

It happens reproducible for i586 only, but not for x86_64, with all the same versions, and not with a local (much faster) build host.

So it is smells like a timing problem.

[   97s] ERROR: test_nlst (test_functional_ssl.TestFtpListingCmdsTLSMixin)
[   97s] ----------------------------------------------------------------------
[   97s] Traceback (most recent call last):
[   97s]   File "/home/abuild/rpmbuild/BUILD/pyftpdlib-1.5.1/pyftpdlib/test/test_functional_ssl.py", line 139, in test_nlst
[   97s]     super(TestFtpListingCmdsTLSMixin, self).test_nlst()
[   97s]   File "/home/abuild/.local/lib/python2.7/site-packages/pyftpdlib-1.5.1-py2.7.egg/pyftpdlib/test/test_functional.py", line 1187, in test_nlst
[   97s]     self._test_listing_cmds('nlst')
[   97s]   File "/home/abuild/.local/lib/python2.7/site-packages/pyftpdlib-1.5.1-py2.7.egg/pyftpdlib/test/test_functional.py", line 1180, in _test_listing_cmds
[   97s]     self.client.retrlines('%s %s' % (cmd, tempdir), x.append)
[   97s]   File "/usr/lib/python2.7/ftplib.py", line 735, in retrlines
[   97s]     conn.unwrap()
[   97s]   File "/usr/lib/python2.7/ssl.py", line 289, in unwrap
[   97s]     s = self._sslobj.shutdown()
[   97s] error: [Errno 0] Error