Convert deprecated behavior of assertRaises() etc into errors

[serhiy-storchaka]

BPO	34318
Nosy	@rbtcollins, @ezio-melotti, @voidspace, @serhiy-storchaka
PRs	bpo-34318: Convert deprecation warnings to errors in assertRaises() etc. #8623

^{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 2018-08-19.07:49:21.709>
created_at = <Date 2018-08-02.11:39:54.574>
labels = ['tests', '3.8', 'type-feature', 'library']
title = 'Convert deprecated behavior of assertRaises() etc into errors'
updated_at = <Date 2018-08-19.07:49:21.708>
user = 'https://github.com/serhiy-storchaka'

bugs.python.org fields:

activity = <Date 2018-08-19.07:49:21.708>
actor = 'serhiy.storchaka'
assignee = 'none'
closed = True
closed_date = <Date 2018-08-19.07:49:21.709>
closer = 'serhiy.storchaka'
components = ['Library (Lib)', 'Tests']
creation = <Date 2018-08-02.11:39:54.574>
creator = 'serhiy.storchaka'
dependencies = []
files = []
hgrepos = []
issue_num = 34318
keywords = ['patch']
message_count = 2.0
messages = ['322946', '323745']
nosy_count = 4.0
nosy_names = ['rbcollins', 'ezio.melotti', 'michael.foord', 'serhiy.storchaka']
pr_nums = ['8623']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue34318'
versions = ['Python 3.8']

[serhiy-storchaka]

Currently assertRaises(), assertRaisesRegex(), assertWarns() and assertWarnsRegex() have some weird behavior.

    # always success if the callable is None
    self.assertRaises(SomeException, None)

    # keyword arguments except "msg" are ignored
    with self.assertRaises(SomeException, foobar=123):
        ...

    # always success because keyword arguments are ignored
    self.assertRaises(SomeException, callable=func)

Hardly any user code uses these "features" intentionally. More likely such examples are hidden bugs (see for example [1]). A DeprecationWarning is raised in these cases since 3.5 (bpo-24134), and it is time to make them errors.

[1] https://mail.python.org/pipermail/python-list/2018-July/736363.html

[serhiy-storchaka]

New changeset 77d5781 by Serhiy Storchaka in branch 'master':
bpo-34318: Convert deprecation warnings to errors in assertRaises() etc. (GH-8623)
77d5781