[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Berker Peksag added the comment: New changeset af88e7eda4101f36e904771d3cf59a5f740b3b00 by Berker Peksag (Nathaniel J. Smith) in branch 'master': bpo-27122: Fix comment to point to correct issue number (#47) https://github.com/python/cpython/commit/af88e7eda4101f36e904771d3cf59a5f740b3b00 ---

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Berker Peksag added the comment: New changeset 89b1824e693419b20b6a9113e5293f1c1a78065f by Berker Peksag in branch '3.6': bpo-27122: Fix comment to point to correct issue number (#48) https://github.com/python/cpython/commit/89b1824e693419b20b6a9113e5293f1c1a78065f -- ___

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Berker Peksag added the comment: New changeset c6d2f498142c29ed62241ab6d89cb7b5e38f2fca by Berker Peksag in branch '3.5': bpo-27122: Fix comment to point to correct issue number (#50) https://github.com/python/cpython/commit/c6d2f498142c29ed62241ab6d89cb7b5e38f2fca -- nosy: +berker.pe

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Berker Peksag added the comment: New changeset c6d2f498142c29ed62241ab6d89cb7b5e38f2fca by GitHub in branch '3.5': bpo-27122: Fix comment to point to correct issue number (#50) https://github.com/python/cpython/commit/c6d2f498142c29ed62241ab6d89cb7b5e38f2fca -- nosy: +berker.peksag _

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Berker Peksag added the comment: New changeset 89b1824e693419b20b6a9113e5293f1c1a78065f by GitHub in branch '3.6': bpo-27122: Fix comment to point to correct issue number (#48) https://github.com/python/cpython/commit/89b1824e693419b20b6a9113e5293f1c1a78065f -- nosy: +berker.peksag _

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Gregory P. Smith added the comment: we talented! -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mai

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Carl Meyer added the comment: Greg, there was also a (different!) typo of the issue number in the code comment committed with this fix; that typo hasn't been fixed. Sent me on quite the chase looking for this bug. (I tracked down the bug independently, then wasn't able to repro it on trunk and

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Serhiy Storchaka : -- status: open -> closed ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https:/

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Roundup Robot added the comment: New changeset a14b93a4eb49 by Serhiy Storchaka in branch '3.5': Added more tests for issue #27122. https://hg.python.org/cpython/rev/a14b93a4eb49 New changeset ebc82b840163 by Serhiy Storchaka in branch 'default': Added more tests for issue #27122. https://hg.pyt

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Nick Coghlan added the comment: Serhiy's test changes look good to me! -- ___ Python tracker ___ ___ Python-bugs-list mailing list Uns

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Serhiy Storchaka added the comment: Here are additional tests. -- status: closed -> open Added file: http://bugs.python.org/file43447/issue27122-additional-tests.patch ___ Python tracker ___

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Nick Coghlan added the comment: There's an existing scenario test at https://hg.python.org/cpython/file/default/Lib/test/test_contextlib.py#l600 and https://hg.python.org/cpython/file/default/Lib/test/test_contextlib.py#l648 that aims to ensure ExitStack unwinding and context setting matches t

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Serhiy Storchaka added the comment: Is it worth to add more specific tests for __context__ and __cause__ attributes of an exception? -- nosy: +serhiy.storchaka ___ Python tracker __

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Roundup Robot added the comment: New changeset 6bb68eae63e8 by Gregory P. Smith in branch '3.5': issue27122: fix typo in the news file, wrong issue #. not issue27123. https://hg.python.org/cpython/rev/6bb68eae63e8 New changeset 4e1dbfcc9449 by Gregory P. Smith in branch 'default': issue27122: f

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Gregory P. Smith : -- resolution: -> fixed stage: -> resolved status: open -> closed type: -> behavior ___ Python tracker ___ __

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Gregory P. Smith added the comment: (with a follow up change to fix the typo in the news file which the bot hasn't seen fit to mention here yet) i'm removing the 25782 dependency as that isn't blocking fixing this. -- dependencies: -CPython hangs on error __context__ set to the error

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Gregory P. Smith added the comment: Fixes are in 3.5 and default: remote: notified python-check...@python.org of incoming changeset 9ee36b74b432 remote: notified python-check...@python.org of incoming changeset 9fadeee05880 -- ___ Python tracker

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Nick Coghlan : -- assignee: ncoghlan -> gregory.p.smith ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscrib

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Nick Coghlan added the comment: Greg, I think you should apply your change to eliminate the regression and get us back to the state of all stdlib context managers being well-behaved in this regard (we unfortunately missed the 3.5.2 release, but that will ensure it's fixed for 3.5.3). Given th

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Gregory P. Smith : -- assignee: gregory.p.smith -> ncoghlan ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubs

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Gregory P. Smith added the comment: Proposed fix based on STINNER and Nick's earlier comments and the simple reproducer turned into a test. Nick - your most recent comment makes me wonder if this shouldn't be doing more. this does make both hang_bug*.py examples do something reasonable. I'm a

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Gregory P. Smith : -- dependencies: +CPython hangs on error __context__ set to the error itself ___ Python tracker ___ ___

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Gregory P. Smith : -- assignee: -> gregory.p.smith ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Nick Coghlan added the comment: Experimenting with this locally, it looks like the C level hang is indeed due to #25782, but the fact that we're implicitly trying to do "exc.__context__ = exc" is a new bug in _GeneratorContextManager introduced by the PEP 479 changes. However, I'm now wonderin

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by Gregory P. Smith : -- nosy: +gregory.p.smith -gps ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: ht

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Emanuel Barry added the comment: Yes, and it seems that it is waiting for a review. http://bugs.python.org/issue25782 -- nosy: +ebarry ___ Python tracker ___ ___

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Yury Selivanov added the comment: > > Maybe we should deny setting "exc.__context__=exc" (modify > PyException_SetContext for that). Maybe raise a new RuntimeError in this case? There is a patch for that somewhere on the tracker -- ___ Python track

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

STINNER Victor added the comment: > The loop seems to be in PyErr_SetObject in a loop that recursively go through > PyException_GetContext. We should also fix this function to avoid the infinite loop. Maybe we should deny setting "exc.__context__=exc" (modify PyException_SetContext for that).

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Nick Coghlan added the comment: The suggested fix looks basically correct to me - the problem is that the new except clause added by that patch is currently missing the "don't re-raise the passed in exception" logic needed to fully abide by the context management protocol, but we missed that o

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

STINNER Victor added the comment: Simplified script to reproduce the bug. -- nosy: +haypo Added file: http://bugs.python.org/file42999/hang_bug2.py ___ Python tracker ___ ___

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

STINNER Victor added the comment: Workaround, or maybe fix?, for the issue: diff -r 0af15b8ef3b2 Lib/contextlib.py --- a/Lib/contextlib.py Thu May 12 10:37:58 2016 +0300 +++ b/Lib/contextlib.py Wed May 25 15:56:50 2016 +0200 @@ -87,6 +87,8 @@ class _GeneratorContextManager(ContextDe

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

STINNER Victor added the comment: It's a regression introduced by the PEP 479 in Lib/contextlib.py by the changeset 36a8d935c322, "PEP 479: Change StopIteration handling inside generators (Closes issue #22906)". -- ___ Python tracker

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by STINNER Victor : -- nosy: +yselivanov ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.p

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by R. David Murray : -- nosy: +ncoghlan ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.py

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

Changes by R. David Murray : -- nosy: +gps ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.

[issue27122] Hang with contextlib.ExitStack and subprocess.Popen (regression)

New submission from Valentin David: The attached script hangs while using 100% on Python 3.5.1 but not on Python 3.4.3. Tested both on Gentoo Linux and Ubuntu Linux. The loop seems to be in PyErr_SetObject in a loop that recursively go through PyException_GetContext. subprocess.Popen seems to