Issue 37585: Comparing PyDictValues does not give expected results (original) (raw)
Created on 2019-07-13 11:58 by Kristian Klette, last changed 2022-04-11 14:59 by admin. This issue is now closed.
Messages (8)
Author: Kristian Klette (Kristian Klette) *
Date: 2019-07-13 11:58
As a user, I expect to be able to compare the different parts a dict
in the same manner.
Currently, PyDictValues does not implement the dictview_richcompare, causing the __eq__ to always return false, even if the values are identical.
my_dict = {'foo': 'bar'}
dict_copy = my_dict.copy()
other_dict = {'foo': 'bar', 'bar': 1234}
assert my_dict.keys() == my_dict.keys()
assert my_dict.keys() == dict_copy.keys()
assert my_dict.keys() != other_dict.keys()
assert my_dict.items() == my_dict.items()
assert my_dict.items() == dict_copy.items()
assert my_dict.items() != other_dict.items()
assert my_dict.values() == my_dict.values()
assert my_dict.values() == dict_copy.values()
assert my_dict.values() != other_dict.values()
Author: Karthikeyan Singaravelan (xtreak) * 
Date: 2019-07-13 12:36
See also which was a similar proposal rejected in the past.
Author: Kyle Stanley (aeros) *
Date: 2019-07-26 05:31
Based on the current status of the discussion in python-dev, the most agreed upon solution so far seems to be updating the documentation to mention this behavior, rather than modifying the existing behavior. I opened a PR which updates the documentation for dict.values() to mention this, feel free to leave any suggestions.
python-dev discussion archive: https://mail.python.org/archives/list/python-dev@python.org/thread/R2MPDTTMJXAF54SICFSAWPPCCEWAJ7WF/#723CHZBH4ZBKQJOOPXFFX3HYSPDBPDPR
Author: Kyle Stanley (aeros) *
Date: 2019-07-26 05:35
Added Brett to the nosy list since he was the one who suggested a documentation change.
Author: Kyle Stanley (aeros) *
Date: 2019-08-23 08:23
Reopening the issue for adding the documentation clarification, that comparing the values view of two dictionaries will always return false (as was suggested in the ML discussion https://mail.python.org/archives/list/python-dev@python.org/message/K3SYX4DER3WAOWGQ4SPKCKXSXLXTIVAQ/). A month ago, I opened to PR to add the clarification to the documentation for dict.values(): https://github.com/python/cpython/pull/14954/files.
It probably went unnoticed because the issue had already been closed (which I hadn't realized at the time).
Author: Brett Cannon (brett.cannon) *
Date: 2019-09-11 10:01
New changeset 6472ece5a0fe82809d3aa0ffb281796fcd252d76 by Brett Cannon (Kyle Stanley) in branch 'master': bpo-37585: Add clarification regarding comparing dict.values() (GH-14954) https://github.com/python/cpython/commit/6472ece5a0fe82809d3aa0ffb281796fcd252d76
Author: miss-islington (miss-islington)
Date: 2019-09-11 10:45
New changeset 3cd147bf599f116593dc06ed7dfe948b759aabd3 by Miss Islington (bot) in branch '3.7': bpo-37585: Add clarification regarding comparing dict.values() (GH-14954) https://github.com/python/cpython/commit/3cd147bf599f116593dc06ed7dfe948b759aabd3
Author: miss-islington (miss-islington)
Date: 2019-09-11 10:46
New changeset 690a16d455603500a0c6df0bd87e49c9b37a6950 by Miss Islington (bot) in branch '3.8': bpo-37585: Add clarification regarding comparing dict.values() (GH-14954) https://github.com/python/cpython/commit/690a16d455603500a0c6df0bd87e49c9b37a6950
History
Date
User
Action
Args
2022-04-11 14:59:18
admin
set
github: 81766
2019-09-11 10:46:55
miss-islington
set
messages: +
2019-09-11 10:45:57
miss-islington
set
nosy: + miss-islington
messages: +
2019-09-11 10:03:37
brett.cannon
set
status: open -> closed
stage: patch review -> resolved
2019-09-11 10:01:59
miss-islington
set
pull_requests: + <pull%5Frequest15550>
2019-09-11 10:01:53
miss-islington
set
pull_requests: + <pull%5Frequest15549>
2019-09-11 10:01:45
brett.cannon
set
messages: +
2019-08-23 21:35:38
aeros
set
stage: resolved -> patch review
2019-08-23 08:23:10
aeros
set
status: closed -> open
messages: +
2019-07-26 05:35:02
aeros
set
nosy: + brett.cannon
messages: +
2019-07-26 05:31:33
aeros
set
nosy: + aeros
messages: +
2019-07-26 05:28:32
aeros
set
pull_requests: + <pull%5Frequest14723>
2019-07-13 12:49:40
serhiy.storchaka
set
status: open -> closed
resolution: duplicate
superseder: dict view values objects are missing tp_richcmp and tp_as_number
stage: patch review -> resolved
2019-07-13 12:36:58
xtreak
set
nosy: + xtreak, methane
messages: +
2019-07-13 12:04:11
python-dev
set
keywords: + patch
stage: patch review
pull_requests: + <pull%5Frequest14531>
2019-07-13 11:58:48
Kristian Klette
create