classification
Title: Random failure in test_idle
Type: behavior Stage:
Components: IDLE, Tests Versions: Python 3.8
process
Status: open Resolution:
Dependencies: Superseder:
Assigned To: terry.reedy Nosy List: cheryl.sabella, serhiy.storchaka, terry.reedy
Priority: normal Keywords:

Created on 2019-03-14 06:34 by serhiy.storchaka, last changed 2019-03-15 05:11 by terry.reedy.

Files
File name Uploaded Description Edit
test_cdfail.py terry.reedy, 2019-03-15 05:11
Messages (2)
msg337897 - (view) Author: Serhiy Storchaka (serhiy.storchaka) * (Python committer) Date: 2019-03-14 06:34
I have got a failure in test_idle:

0:00:21 load avg: 3.40 [ 76/420/1] test_idle failed
test test_idle failed -- Traceback (most recent call last):
  File "/home/serhiy/py/cpython-clinic/Lib/idlelib/idle_test/test_configdialog.py", line 104, in test_fontlist_key
    self.assertNotEqual(down_font, font)
AssertionError: 'Abyssinica SIL' == 'Abyssinica SIL'

It has not reproduced when run test_idle separately.
msg337964 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2019-03-15 05:11
I am guessing that test_idle and hence this test have been run over 500 days X 20 runs/day (10000 times) since merged.  This is the first report I have seen, though failures that get retested would be masked.  My guess is a sporadic timing delay such that the assertion is tested before the widget is updated.  Serhiy, does this make sense?

I have reproduced the failure 8 times by running the attached file, derived from test_configdialog, in IDLE.  Reps required ranged from about 1000 to 30000, plus I stopped once at nearly 100000 with no failure.  About half appeared to be a direct result.  All appeared to be an up/down font test, the first of the pair.

Tomorrow, I intend to run this more, including from command line, and then insert update() or update_idletasks() to see if either dependably suppress failure.  I am curious what happens on Linux.
History
Date User Action Args
2019-03-15 05:11:50terry.reedysetfiles: + test_cdfail.py
nosy: + cheryl.sabella
messages: + msg337964

2019-03-14 06:34:05serhiy.storchakacreate