Incorrectly pluralized abstract class error message

[pppery]

BPO	34331
Nosy	@rhettinger, @terryjreedy, @ericvsmith, @serhiy-storchaka, @matrixise, @pppery, @CuriousLearner, @tirkarthi, @bansalanjali2512
PRs	bpo-34331: Fix incorrectly pluralized abstract class error message. #8670

^{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 2019-09-11.15:30:39.215>
created_at = <Date 2018-08-03.15:56:31.694>
labels = ['interpreter-core', 'type-bug', 'library', '3.9']
title = 'Incorrectly pluralized abstract class error message'
updated_at = <Date 2019-09-11.15:30:39.213>
user = 'https://github.com/pppery'

bugs.python.org fields:

activity = <Date 2019-09-11.15:30:39.213>
actor = 'matrixise'
assignee = 'none'
closed = True
closed_date = <Date 2019-09-11.15:30:39.215>
closer = 'matrixise'
components = ['Interpreter Core', 'Library (Lib)']
creation = <Date 2018-08-03.15:56:31.694>
creator = 'ppperry'
dependencies = []
files = []
hgrepos = []
issue_num = 34331
keywords = ['patch']
message_count = 7.0
messages = ['323059', '323071', '323072', '323088', '349310', '351942', '351944']
nosy_count = 9.0
nosy_names = ['rhettinger', 'terry.reedy', 'eric.smith', 'serhiy.storchaka', 'matrixise', 'ppperry', 'CuriousLearner', 'xtreak', 'bansalanjali']
pr_nums = ['8670']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue34331'
versions = ['Python 3.9']

[pppery]

>>> class abstract(abc.ABC):
...     @abc.abstractmethod
...     def meth():
...         pass
...
>>> x()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Can't instantiate abstract class x with abstract methods meth

Error should be "Can't instantiate abstract class abstract with abstract method meth" in the singular, because there is only one abstract method.

[ericvsmith]

I'm not sure the effort and code is justified for a trivial fix to an error message. Is this causing some actual problem?

[pppery]

No, this isn't causing me an actual problem, however the related bpo-34127 was accepted, and this one should be no harder to fix.

[ericvsmith]

Actually, this one is probably easier to fix. In my opinion, bpo-34127 is more important to fix, since it's seen much more often than the message about abstract base classes.

I wouldn't necessarily object to fixing this one, I just personally think it's not worth the hassle.

[CuriousLearner]

Adding 3.9 to this bug. I've reviewed the PR and it looks good to me.

[matrixise]

New changeset 4a12a17 by Stéphane Wirtel (Daniel Andrade) in branch 'master':
bpo-34331: Fix incorrectly pluralized abstract class error message. (GH-8670)
4a12a17

[matrixise]

Thank you for your contribution