tests fail on 1-core VM

[bmwiedemann]

While working on reproducible builds for openSUSE, I found that our python-pyftpdlib-1.5.6 package failed its tests when built in a 1-core VM.

To reproduce, one can also use

taskset 1 python3 -m pytest

 pyftpdlib/test/test_functional.py::TestTimeouts::test_idle_data_timeout2 FAILED [ 18%]
 pyftpdlib/test/test_functional_ssl.py::TestTimeouts::test_idle_data_timeout2 FAILED [ 35%]
 pyftpdlib/test/test_functional_ssl.py::TestFtpListingCmdsTLSMixin::test_nlst FAILED [ 46%]
 pyftpdlib/test/test_functional_ssl.py::TestFtpListingCmdsTLSMixin::test_stat FAILED [ 46%]
 pyftpdlib/test/test_functional_ssl.py::TestTimeoutsTLSMixin::test_idle_data_timeout2 FAILED [ 48%]

 self = <pyftpdlib.test.test_functional_ssl.TestFtpListingCmdsTLSMixin testMethod=test_stat>
 
     def tearDown(self):
         close_client(self.client)
 >       self.server.stop()
 
     def assert_free_resources():
         ts = threading.enumerate()
         assert len(ts) == 1, ts
         p = psutil.Process()
         children = p.children()
         if children:
             for p in children:
                 p.kill()
                 p.wait(1)
 >           assert not children, children
 E           AssertionError: [psutil.Process(pid=1364, status='terminated')]

====== 5 failed, 714 passed, 55 skipped, 3 deselected, 1 error in 42.03s =======

[mcepl]

We have occasionally this one in our build system (openSUSE when packaging pyftpdlib for our distribution).

This is complete build log with all details about packages used, steps taken etc.