3.9.0 test_site warning: "urllib.requests._opener was modified by test_site"

[ned-deily]

BPO	41939
Nosy	@vstinner, @ned-deily, @ambv, @miss-islington
PRs	bpo-41939: Fix test_site.test_license_exists_at_url() #22559 [3.9] bpo-41939: Fix test_site.test_license_exists_at_url() (GH-22559) #22567 [3.8] bpo-41939: Fix test_site.test_license_exists_at_url() (GH-22559) #22574 bpo-41939: do not skip test_site.test_license_exists_at_url for pre-releases #22688 [3.9] bpo-41939: always enable test_site.test_license_exists_at_url (GH-22688) #22689 [3.8] bpo-41939: always enable test_site.test_license_exists_at_url (GH-22688) #22690

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2020-10-06.07:11:48.046>
created_at = <Date 2020-10-05.07:01:03.150>
labels = ['deferred-blocker', 'type-bug', '3.8', '3.9', '3.10', 'tests']
title = '3.9.0 test_site warning: "urllib.requests._opener was modified by test_site"'
updated_at = <Date 2020-10-14.15:46:22.048>
user = 'https://github.com/ned-deily'

bugs.python.org fields:

activity = <Date 2020-10-14.15:46:22.048>
actor = 'vstinner'
assignee = 'none'
closed = True
closed_date = <Date 2020-10-06.07:11:48.046>
closer = 'vstinner'
components = ['Tests']
creation = <Date 2020-10-05.07:01:03.150>
creator = 'ned.deily'
dependencies = []
files = []
hgrepos = []
issue_num = 41939
keywords = ['patch']
message_count = 11.0
messages = ['377995', '377997', '377998', '378059', '378064', '378093', '378592', '378595', '378596', '378597', '378627']
nosy_count = 4.0
nosy_names = ['vstinner', 'ned.deily', 'lukasz.langa', 'miss-islington']
pr_nums = ['22559', '22567', '22574', '22688', '22689', '22690']
priority = 'deferred blocker'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue41939'
versions = ['Python 3.8', 'Python 3.9', 'Python 3.10']

[ned-deily]

For 3.9.0, test_site fails with an env changed warning:

Warning -- urllib.requests._opener was modified by test_site
Before: None
After: <urllib.request.OpenerDirector object at 0xb76f4f88>
test_site failed (env changed)

== Tests result: SUCCESS ==

1 test altered the execution environment:
test_site

The problem occurs in test_site's test_license_exists_at_url test and was introduced by the changes in bpo-37421: "Some tests leak temporary files".

This failure has not been noticed up to now because test_license_exists_at_url is skipped unless the build being tested is for a released branch, which is about to happen for 3.9 with the 3.9.0 release. The test failure can be reproduced on any build by commenting out Lib/test_site.py lines 503-504:

@unittest.skipUnless(sys.version_info[3] == 'final',
                     'only for released versions')

Setting to "deferred blocker" status for release manager evaluation.

[vstinner]

It's a minor issue in the test itself, not in urllib. Such bug should not block a release.

[vstinner]

I proposed PR 22559 to fix the issue.

See also bpo-37475: "What is urllib.request.urlcleanup() function?".

[ambv]

New changeset 1fce240 by Victor Stinner in branch 'master':
bpo-41939: Fix test_site.test_license_exists_at_url() (bpo-22559)
1fce240

[ambv]

New changeset 10b4136 by Miss Skeleton (bot) in branch '3.9':
bpo-41939: Fix test_site.test_license_exists_at_url() (GH-22559) (bpo-22567)
10b4136

[miss-islington]

New changeset 78bddc7 by Miss Skeleton (bot) in branch '3.8':
bpo-41939: Fix test_site.test_license_exists_at_url() (GH-22559)
78bddc7

[ned-deily]

New changeset 6a48518 by Ned Deily in branch 'master':
bpo-41939: always enable test_site.test_license_exists_at_url (GH-22688)
6a48518

[miss-islington]

New changeset 8b4642d by Miss Skeleton (bot) in branch '3.8':
bpo-41939: always enable test_site.test_license_exists_at_url (GH-22688)
8b4642d

[miss-islington]

New changeset 881a13c by Miss Skeleton (bot) in branch '3.9':
bpo-41939: always enable test_site.test_license_exists_at_url (GH-22688)
881a13c

[ned-deily]

Thanks for the fix, Victor.

Sometime after filing this, I remembered that we had seen a similar problem some years ago and found bpo-21572 in which I had changed Lib/site.py to no longer use a release-dependent URL for the license file - which is why the check to skip if on a pre-release had been added previously to test_license_exists_at_url. So I should have removed the skip in test_site at the same time as it is no longer needed and hides problems like this until the final release. PR 22688 and its backports remove the skip.

[vstinner]

You're welcome ;-)