pytest==5.0.0 shows glitched output for tests/misc_tests/test_async.py

[muupan]

Example from https://travis-ci.org/chainer/chainerrl/jobs/552661480:

tests/misc_tests/test_async.py .Fatal Python error: Segmentation fault
Current thread 0x00007f21c81c2740 (most recent call first):
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 202 in run_with_exit_code_11
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 130 in set_seed_and_run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 93 in run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 258 in _bootstrap
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 74 in _launch
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 20 in __init__
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 277 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 223 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 105 in start
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 137 in run_async
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 213 in test_run_async_exit_code
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 605 in run
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 653 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/unittest.py", line 200 in runtest
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 117 in pytest_runtest_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 220 in from_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in call_runtest_hook
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 167 in call_and_report
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 87 in runtestprotocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 72 in pytest_runtest_protocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 278 in pytest_runtestloop
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 257 in _main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 213 in wrap_session
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 250 in pytest_cmdline_main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/config/__init__.py", line 74 in main
  File "/home/travis/virtualenv/python3.6.3/bin/pytest", line 10 in <module>
Fatal Python error: Segmentation fault
Current thread 0x00007f21c81c2740 (most recent call first):
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 202 in run_with_exit_code_11
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 130 in set_seed_and_run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 93 in run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 258 in _bootstrap
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 74 in _launch
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 20 in __init__
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 277 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 223 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 105 in start
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 137 in run_async
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 213 in test_run_async_exit_code
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 605 in run
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 653 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/unittest.py", line 200 in runtest
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 117 in pytest_runtest_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 220 in from_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in call_runtest_hook
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 167 in call_and_report
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 87 in runtestprotocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 72 in pytest_runtest_protocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 278 in pytest_runtestloop
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/managerFatal Python error: Segmentation fault
Current thread 0x00007f21c81c2740 (most recent call first):
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.p.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
y  File "", line /202ho in mre/utnr_awivtihs_/evxiirtt_ucaoldeen_v1/1p
y  File t"ho/nh3o.m6e./3t/rlaivbi/sp/ybtuhiolnd3/.c6h/asiinter/chaineer-rpla/cckhaagiense/r_rply/tmeissc/ats/ynmca_i.npy", line 130. in psye"t, line _257s in e_edm_aainnd
_  File r"un/
h  File o"me//otprta/vpiyst/hvoinr/t3u.a6l.e3n/vl/ipby/tphyotnh3o.n63..36//lmiubl/tpiyptrhoocne3s.s6i/nsgi/proctees-sp.apcyk"a, line g93e in sr/u_np
y  File te"s/to/pmta/ipny.tphy"o, line n/2133 in .w6r.a3p/_lsiebs/spiyotnh
o  File n3"./6h/ommuel/ttirparvoicse/svsiirntuaglenv/python/process.py", line 258 in 3_.b6o.3otstrap
  File "/opt/python/3.6.3//lliibb//ppyytthon3.h6o/nm3u.ltipro6/site-cpeascskiangge/sp/o_ppeytne_sfto/rmka.ipny."p, line y"74, line  in _250l in apuyntcehs
t_  File c"m/dolpitn/ep_ymatihno
n/3.6.  File 3"/l/homie/bt/rpayvtihso/nv3i.r6t/umaulletnivp/rpoyctehsosni3n.g6/.p3o/pleibn/_pfyotrhk.pon3y."6, line /s20i in t_e_-ipnaictk_ages/p_l
u  File g"gy//ocpat/pytlhloenr/3s..6p.y3"/, line l187ib/p in y_tmhuolnt3i.c6a/lmull
t  File i"p/rhoocmeessi/travis/vinrgt/ucaontlenv/epxt.py", line 277 in _Popen
  File "/oyptt/hpoynt3h.o6n./33/.l6i.3/lib/python3.6/multiprocessing/cb/python3.6/site-packageso/ntexptl.upgy", line gy223/ in m_aPnoapgeenr.
p  File y"", line /81o in p<tl/apmybtdhaon>/
3  File .6"./3h/olmieb//tpryatvhiosn/3v.i6r/tmuuallteinpvr/opcyetshsoinn3g./6process.py"., line 3/105l in isb/tpayrtt
h  File on"3./6/hsoimtee/-tpraacvkias/gbeusi/lpdl/ucghgayi/nmearn/acghear.ipnye"r, line r87l/ in c_hhaoionkeerxrelc/
m  File i"sc//haosmyen/ct_r.apvyi"s, line /137v in irrutnu_aalseynnvc/
p  File yt"h/ohno3m.e6/.t3r/alviibs//pbyutihlodn/3c.h6a/isnietre/-cphacakiangeersr/lp/ltuegsgtys//hmoioskcs_.tpeys"t, line s/289t in e_s_tc_aalsly_n_c
.  File py""/, line h213o in mtee/sttr_run_async_aevxiist/_vciordet
u  File al"e/novp/tp/yptyhtohno3n./6.33./6l.i3b//lpiybt/hpoynt3h.o6n/3s.i6/tuen-iptatceksatg/ecsa/s_ep.yptye"s, line t/605c in ornufni
g  File /"_/_oipnti/t_p_y.tphyo"n, line /374. in 6m.a3i/nl
i  File b"/p/yhtohmoen/3t.r6a/vuinsi/tvirttueaslte/ncva/spey.tphyo"n, line 3.6653. in 3_/_bcianl/lp_y_t
es  File t"", line /10h in o<mem/otdrualvei>s
/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/unittest.py", line 200 in runtest
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 117 in pytest_runtest_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 220 in from_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in call_runtest_hook
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 167 in call_and_report
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 87 in runtestprotocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 72 in pytest_runtest_protocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 278 in pytest_runtestloop
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 257 in _main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 213 in wrap_session
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 250 in pytest_cmdline_main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/config/__init__.py", line 74 in main
  File "/home/travis/virtualenv/python3.6.3/bin/pytest", line 10 in <module>
Fatal Python error: Segmentation fault
Current thread 0x00007f21c81c2740 (most recent call first):
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 202 in run_with_exit_code_11
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 130 in set_seed_and_run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 93 in run
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 258 in _bootstrap
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 74 in _launch
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/popen_fork.py", line 20 in __init__
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 277 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/context.py", line 223 in _Popen
  File "/opt/python/3.6.3/lib/python3.6/multiprocessing/process.py", line 105 in start
  File "/home/travis/build/chainer/chainerrl/chainerrl/misc/async_.py", line 137 in run_async
  File "/home/travis/build/chainer/chainerrl/tests/misc_tests/test_async.py", line 213 in test_run_async_exit_code
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 605 in run
  File "/opt/python/3.6.3/lib/python3.6/unittest/case.py", line 653 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/unittest.py", line 200 in runtest
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 117 in pytest_runtest_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 220 in from_call
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 192 in call_runtest_hook
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 167 in call_and_report
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 87 in runtestprotocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/runner.py", line 72 in pytest_runtest_protocol
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 278 in pytest_runtestloop
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 257 in _main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 213 in wrap_session
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/main.py", line 250 in pytest_cmdline_main
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/callers.py", line 187 in _multicall
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 81 in <lambda>
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/manager.py", line 87 in _hookexec
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/pluggy/hooks.py", line 289 in __call__
  File "/home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages/_pytest/config/__init__.py", line 74 in main
  File "/home/travis/virtualenv/python3.6.3/bin/pytest", line 10 in <module>

pytest==4.6.1 does not have this issue.

It seems like this does not affect the CI results, though.