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Title: Add environment variable $PYTHONWARNINGS
Type: enhancement Stage: patch review
Components: Library (Lib) Versions: Python 3.2, Python 2.7
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: pjenvey Nosy List: barry, brian.curtin, eric.araujo, pitrou, pjenvey, skrah
Priority: normal Keywords: needs review, patch

Created on 2009-11-10 15:05 by barry, last changed 2022-04-11 14:56 by admin. This issue is now closed.

File name Uploaded Description Edit
issue7301.diff brian.curtin, 2010-02-06 23:33 trunk patch
issue7301-2.diff pjenvey, 2010-04-06 23:03
issue7301-py3k.diff pjenvey, 2010-04-08 01:12
Messages (15)
msg95117 - (view) Author: Barry A. Warsaw (barry) * (Python committer) Date: 2009-11-10 15:05
It would be very useful to have an environment variable $PYTHONWARNINGS,
tied to the -W option for silencing various warnings (most importantly,

Use case: a test suite running many subprocesses, testing that those
subproc output is clean.  DeprecationWarnings cannot easily be
suppressed by passing -W flags all around or using liberally sprinkled
filterwarnings().  Setting $PYTHONWARNINGS once and for all to silence
all processes would be very useful.
msg95200 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2009-11-13 21:15
I attached a patch against trunk r76237 which seems to cover this, sans
official tests. I looked around and didn't find a good place for
specifically testing environment variables. I could add test code in
test_warnings if that's the best place.

The patch allows multiple warnings to be passed to the environment
variable as a comma separated string, and works in conjunction with -W.

Let me know what you think.
msg95202 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2009-11-13 21:28
test_warnings is probably the best place since test_cmd_line ignores 
environment variables
msg95210 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2009-11-13 22:10
Added a patch which includes tests in test_warnings. There are tests for
a single warning, two comma separated warnings, and one env var warning
and one command line warning at the same time.
msg97797 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-01-15 00:40
fixed a tab/space issue
msg98972 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-02-06 23:33
Updated patch, tests weren't working.
msg102504 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-06 23:03
Looks good to me. Updated patch with a couple whitespace changes
msg102505 - (view) Author: Barry A. Warsaw (barry) * (Python committer) Date: 2010-04-06 23:14
Patch looks good to me too.  Do any of you have commit privileges?  If so, please commit this.  If not assign the issue to me and I'll do it.
msg102515 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-07 04:06
applied in r79878 - r79881, thanks!
msg102520 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-07 06:31
I committed a somewhat different version of this patch to py3k to handle the warn options now calling for wchars, but this needs more work. Some of the buildbots are unhappy

Seems like the py3k version either needs to fully decode the env values to a unicode obj via the file system encoding (which I doubt is initialized at this point)/surrogateescape, or use something along the lines of char2wchar in python.c
msg102582 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-08 01:12
Here's a patch for py3k using the same char2wchar as the argv decoder for posix, and better windows handling. Plus an additional nonascii value test. Patch is against r79980 for clarity
msg102761 - (view) Author: Antoine Pitrou (pitrou) * (Python committer) Date: 2010-04-10 02:24
The tests don't look good to me. You should use p.communicate() rather than Also, check the error return code and raise an error if it's non-zero.
msg102887 - (view) Author: Stefan Krah (skrah) * (Python committer) Date: 2010-04-11 21:00
The changes in main.c in r79881 don't look right:

strtok() is used on the string returned by getenv(), which must not
be modified.

Also (and this admittedly cosmetic), perhaps use a static buffer like
wchar_t warning[128] or use a single allocation before the for loop.
What is the maximum length for a single warning?
msg102888 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-11 21:10
The pending patch for py3k fixes the modification of the env value (trunk already has a fix for that).

That patch is also doing the conversion to wchar_t via the char2wchar function now, with that reusing a single buffer seems out of the question
msg103146 - (view) Author: Philip Jenvey (pjenvey) * (Python committer) Date: 2010-04-14 21:04
py3k should be taken care of as of r80066+r80075
Date User Action Args
2022-04-11 14:56:54adminsetgithub: 51550
2010-04-14 21:04:43pjenveysetstatus: open -> closed
resolution: accepted -> fixed
messages: + msg103146
2010-04-11 21:10:48pjenveysetmessages: + msg102888
2010-04-11 21:00:24skrahsetnosy: + skrah
messages: + msg102887
2010-04-10 02:24:59pitrousetnosy: + pitrou
messages: + msg102761
2010-04-08 01:12:10pjenveysetfiles: + issue7301-py3k.diff

messages: + msg102582
2010-04-07 06:31:02pjenveysetstatus: closed -> open
assignee: pjenvey
resolution: fixed -> accepted
messages: + msg102520
2010-04-07 04:06:24pjenveysetstatus: open -> closed
resolution: accepted -> fixed
messages: + msg102515
2010-04-06 23:14:50barrysetresolution: accepted
messages: + msg102505
2010-04-06 23:03:17pjenveysetfiles: + issue7301-2.diff

messages: + msg102504
2010-02-06 23:33:39brian.curtinsetfiles: + issue7301.diff

messages: + msg98972
2010-02-06 23:32:38brian.curtinsetfiles: - issue7301.diff
2010-02-06 22:50:08eric.araujosetnosy: + eric.araujo
2010-01-15 00:40:51brian.curtinsetfiles: + issue7301.diff

messages: + msg97797
2010-01-15 00:39:42brian.curtinsetfiles: - issue7301.patch
2010-01-15 00:39:38brian.curtinsetfiles: - issue7301_v2.patch
2010-01-13 02:08:33brian.curtinsetpriority: normal
keywords: + needs review
stage: patch review
2009-11-13 22:10:20brian.curtinsetfiles: + issue7301_v2.patch

messages: + msg95210
2009-11-13 21:28:40pjenveysetmessages: + msg95202
2009-11-13 21:15:46brian.curtinsetfiles: + issue7301.patch

nosy: + brian.curtin
messages: + msg95200

keywords: + patch
2009-11-10 23:58:46pjenveysetnosy: + pjenvey
2009-11-10 15:05:29barrycreate