[Django] #30501: Queryset ordering and Meta.ordering are mutable on expressions with reverse().

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm
Type: Bug | Status: assigned
Component: Database | Version: master
layer (models, ORM) |
Severity: Normal | Keywords:
Triage Stage: Accepted | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
Queryset order and `Meta.ordering` are mutable with `reverse()`.

Bug revealed by running `./runtests.py ordering.test --reverse`
(reproduced at a2c31e12da272acc76f3a3a0157fae9a7f6477ac).

It seems that test added in f218a2ff455b5f7391dd38038994f2c5f8b0eca1
wasn't correct because order mutates on queryset execution in
[https://github.com/django/django/blob/a2c31e12da272acc76f3a3a0157fae9a7f6477ac/django/db/models/sql/compiler.py#L253
SQLCompiler.get_order_by()].

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Ticket URL: <https://code.djangoproject.com/ticket/30501>
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[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm
Type: Bug | Status: assigned

Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:

Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by felixxm):

* Attachment "30501.diff" added.

Tests.

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm
Type: Bug | Status: assigned

Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:

Keywords: | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by felixxm):

* has_patch: 0 => 1

Comment:

[https://github.com/django/django/pull/11405 PR]

--
Ticket URL: <https://code.djangoproject.com/ticket/30501#comment:1>

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm
Type: Bug | Status: assigned

Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:

Keywords: | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by felixxm):

* stage: Accepted => Ready for checkin

--
Ticket URL: <https://code.djangoproject.com/ticket/30501#comment:2>

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm

Type: Bug | Status: closed

Component: Database layer | Version: master
(models, ORM) |

Severity: Normal | Resolution: fixed

Keywords: | Triage Stage: Ready for
| checkin

Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by GitHub <noreply@…>):

* status: assigned => closed
* resolution: => fixed

Comment:

In [changeset:"f8b8b00f0197e52f7a0986fae51462be174dbaea" f8b8b00f]:
{{{
#!CommitTicketReference repository=""
revision="f8b8b00f0197e52f7a0986fae51462be174dbaea"
Fixed #30501 -- Preventing QuerySet.reverse() from mutating expressions in
QuerySet.order_by and Meta.ordering.
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/30501#comment:3>

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm

Type: Bug | Status: closed
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution: fixed
Keywords: | Triage Stage: Ready for
| checkin

Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by Patryk Zawadzki):

Will this be backported to the 2.2 branch?

--
Ticket URL: <https://code.djangoproject.com/ticket/30501#comment:4>

[Django]

#30501: Queryset ordering and Meta.ordering are mutable on expressions with
reverse().
-------------------------------------+-------------------------------------
Reporter: felixxm | Owner: felixxm

Type: Bug | Status: closed
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution: fixed
Keywords: | Triage Stage: Ready for
| checkin

Has patch: 1 | Needs documentation: 0

Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Comment (by felixxm):

I'm sorry, but this doesn't qualify for a backport.

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Ticket URL: <https://code.djangoproject.com/ticket/30501#comment:5>