[Django] #36468: Popup stays blank after adding a related object when filter_horizontal is used

[Django]

#36468: Popup stays blank after adding a related object when filter_horizontal is
used
-------------------------------------+-------------------------------------
Reporter: Juan Rocha | Type: Bug
Status: new | Component:
| contrib.admin
Version: 5.2 | Severity: Normal
Keywords: filter_horizontal; | Triage Stage:
SelectBox; add_to_cache; | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
When using the "Add another" popup for a ***ForeignKey field*** in the
Django admin and the same ModelAdmin has a ManyToManyField with
***filter_horizontal***, the popup window does not close properly after
adding the related object.

Instead, the popup remains open and white (blank), and the browser console
throws the following error:

{{{
:8000/static/admin/js/SelectBox.js:60 Uncaught TypeError: Cannot read
properties of undefined (reading 'push')
at Object.add_to_cache (:8000/static/admin/js/SelectBox.js:60:33)
at :8000/static/admin/j…ctLookups.js:115:31
at NodeList.forEach (<anonymous>)
at updateRelatedSelectsOptions
(:8000/static/admin/j…ctLookups.js:103:24)
at dismissAddRelatedObjectPopup
(:8000/static/admin/j…ctLookups.js:133:17)
at popup_response.js:12:16
add_to_cache @ :8000/static/admin/js/SelectBox.js:60
(anonymous) @ :8000/static/admin/j…bjectLookups.js:115
updateRelatedSelectsOptions @ :8000/static/admin/j…bjectLookups.js:103
dismissAddRelatedObjectPopup @ :8000/static/admin/j…bjectLookups.js:133
(anonymous) @ popup_response.js:12
}}}

This seems to be caused by this block in RelatedObjectLookups.js:

{{{
// Update SelectBox cache for related fields.
if (typeof SelectBox !== "undefined" && SelectBox.cache[currentSelect.id])
{
SelectBox.add_to_cache(select.id, option);
SelectBox.redisplay(select.id);
}
}}}


=== Steps to Reproduce
1. Register a ModelAdmin with:
* A ForeignKey field (with an "Add another" popup)
* A ManyToManyField using filter_horizontal

2. Click the "Add another" button next to the ForeignKey field
3. In the popup, add the new object and submit
4. The popup window stays open with a white screen
5. Console shows a JavaScript error from SelectBox.js


=== Expected Behavior
The popup should close normally and update the original select field with
the new object, as it does when filter_horizontal is not present.

=== Workaround
Commenting out or removing the SelectBox.add_to_cache and
SelectBox.redisplay lines in RelatedObjectLookups.js avoids the error and
restores expected behavior.

=== Version
* Django 5.2.X
* Reproducible in the default admin interface
--
Ticket URL: <https://code.djangoproject.com/ticket/36468>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

[Django]

#36468: Popup stays blank after adding a related object when filter_horizontal is
used
-------------------------------------+-------------------------------------

Reporter: Juan Rocha | Owner: (none)

Type: Bug | Status: new
Component: contrib.admin | Version: 5.2

Severity: Normal | Resolution:

Keywords: filter_horizontal; | Triage Stage:
SelectBox; add_to_cache; | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Description changed by Juan Rocha:

Old description:

New description:

=== Regression
This bug was introduced in commit:

https://github.com/django/django/commit/cd0479ff764272add5e0aba2afcf5649a241ca00

=== Expected Behavior
The popup should close normally and update the original select field with
the new object, as it does when filter_horizontal is not present.

=== Workaround
Commenting out or removing the SelectBox.add_to_cache and
SelectBox.redisplay lines in RelatedObjectLookups.js avoids the error and
restores expected behavior.

=== Version
* Django 5.2.X
* Reproducible in the default admin interface

--

--
Ticket URL: <https://code.djangoproject.com/ticket/36468#comment:1>

[Django]

#36468: Popup stays blank after adding a related object when filter_horizontal is
used
-------------------------------------+-------------------------------------
Reporter: Juan Rocha | Owner: (none)

Type: Bug | Status: closed

Component: contrib.admin | Version: 5.2
Severity: Normal | Resolution:

| worksforme

Keywords: filter_horizontal; | Triage Stage:
SelectBox; add_to_cache; | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------

Changes (by Natalia Bidart):

* resolution: => worksforme
* status: new => closed

Comment:

Hello Juan, thank you for your report. I'm not being able to reproduce:
I'm using the models from #35331 (`State` and `Transition`) and after your
step 3, the pop closes just fine.

Can you please share a test project or some tests so that we can replicate
and validate the issue?
--
Ticket URL: <https://code.djangoproject.com/ticket/36468#comment:2>