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Title: argparse crashes with AssertionError
Type: crash Stage: resolved
Components: Distutils Versions: Python 2.7
Status: closed Resolution: duplicate
Dependencies: Superseder: argparse assertion failure with brackets in metavars
View: 11874
Assigned To: Nosy List: dstufft, eric.araujo, miss-islington, ncoghlan, paul.j3, spaceone
Priority: normal Keywords:

Created on 2015-05-01 04:45 by spaceone, last changed 2022-04-11 14:58 by admin. This issue is now closed.

Pull Requests
URL Status Linked Edit
PR 7527 closed miss-islington, 2018-06-08 10:14
PR 7528 merged miss-islington, 2018-06-08 10:14
PR 7530 merged miss-islington, 2018-06-08 11:11
PR 7553 merged miss-islington, 2018-06-09 01:19
Messages (6)
msg242299 - (view) Author: SpaceOne (spaceone) * Date: 2015-05-01 04:45
Just add an argument with metavar='[PROTOCOL://]HOST[:PORT]' ([...] twice in the string) causes the following traceback:

Traceback (most recent call last):
  File "", line 182, in <module>
    arguments = parser.parse_args()
  File "/usr/lib/python2.7/", line 1701, in parse_args
    args, argv = self.parse_known_args(args, namespace)
  File "/usr/lib/python2.7/", line 1733, in parse_known_args
    namespace, args = self._parse_known_args(args, namespace)
  File "/usr/lib/python2.7/", line 1939, in _parse_known_args
    start_index = consume_optional(start_index)
  File "/usr/lib/python2.7/", line 1879, in consume_optional
    take_action(action, args, option_string)
  File "/usr/lib/python2.7/", line 1807, in take_action
    action(self, namespace, argument_values, option_string)
  File "/usr/lib/python2.7/", line 996, in __call__
  File "/usr/lib/python2.7/", line 2340, in print_help
    self._print_message(self.format_help(), file)
  File "/usr/lib/python2.7/", line 2314, in format_help
    return formatter.format_help()
  File "/usr/lib/python2.7/", line 281, in format_help
    help = self._root_section.format_help()
  File "/usr/lib/python2.7/", line 211, in format_help
  File "/usr/lib/python2.7/", line 332, in _format_usage
    assert ' '.join(opt_parts) == opt_usage
msg242449 - (view) Author: paul j3 (paul.j3) * (Python triager) Date: 2015-05-03 04:08
It's the spaces and/or brackets in the metavar, along with a usage line that is long enough to wrap, that is raising this error.

It's a known problem.
msg319039 - (view) Author: Nick Coghlan (ncoghlan) * (Python committer) Date: 2018-06-08 10:12
New changeset 66f02aa32f1e4adb9f24cf186f8c495399d5ce9b by Nick Coghlan (wim glenn) in branch 'master':
bpo-11874: fix assertion failure in argparse metavar handling (GH-1826)
msg319048 - (view) Author: miss-islington (miss-islington) Date: 2018-06-08 11:06
New changeset 376c272d68cca0975ff0be3d12abf5f67da342d7 by Miss Islington (bot) in branch '3.6':
bpo-11874: fix assertion failure in argparse metavar handling (GH-1826)
msg319052 - (view) Author: miss-islington (miss-islington) Date: 2018-06-08 11:33
New changeset 842985f6c70484ed7b8fc30d0bc05aec73236a98 by Miss Islington (bot) in branch '3.7':
bpo-11874: fix assertion failure in argparse metavar handling (GH-1826)
msg319125 - (view) Author: miss-islington (miss-islington) Date: 2018-06-09 01:28
New changeset 4e6bd247aa955056626bf0cf8dc1c65a587b871f by Miss Islington (bot) in branch '2.7':
bpo-11874: fix assertion failure in argparse metavar handling (GH-1826)
Date User Action Args
2022-04-11 14:58:16adminsetgithub: 68277
2018-06-09 01:28:05miss-islingtonsetmessages: + msg319125
2018-06-09 01:19:25miss-islingtonsetpull_requests: + pull_request7186
2018-06-08 11:33:53miss-islingtonsetmessages: + msg319052
2018-06-08 11:11:23miss-islingtonsetpull_requests: + pull_request7167
2018-06-08 11:06:01miss-islingtonsetnosy: + miss-islington
messages: + msg319048
2018-06-08 10:14:59miss-islingtonsetpull_requests: + pull_request7161
2018-06-08 10:14:00miss-islingtonsetpull_requests: + pull_request7157
2018-06-08 10:12:52ncoghlansetnosy: + ncoghlan
messages: + msg319039
2015-05-05 21:06:35ned.deilysetstatus: open -> closed
superseder: argparse assertion failure with brackets in metavars
resolution: duplicate
stage: resolved
2015-05-03 04:08:46paul.j3setnosy: + paul.j3
messages: + msg242449
2015-05-01 04:45:58spaceonecreate