ClearableFileInput widget forgets "Clear" selection when form is not valid

[bmihelac]

ClearableFileInput widget forgets "Clear" selection when form is not valid, that causes file would not be deleted once when form is valid again. This can be inconvinient, especially for forms with many fields.

To reproduce:

1. Choose admin for any model instance where attachment is not required and has some validation,
2. check "Clear" next to the attachment, and change the form, so validation would fail,
3. Save form, validation error would occur, attachment and "Clear" would be empty
4. make form valid again and Save, attachment woult not be cleared

(I am attaching example screenshots)

https://code.djangoproject.com/attachment/ticket/34488/clearable-file-input-before.png

https://code.djangoproject.com/attachment/ticket/34488/clearable-file-input-validation-error.png

https://code.djangoproject.com/attachment/ticket/34488/clearable-file-input-validation-success.png

[bmihelac]

initial state

[bmihelac]

validation error occurs (ClearableFileInput has no file and has no Clear checkbox)

[bmihelac]

File is not removed after successful validation and saving

[Baha Sdtbekov]

Hello, could you please share your models, forms and admin?
Because everything works fine for me.

[Mariusz Felisiak]

Duplicate of #19215 (fixed in c0fc1b5302f5d9d82e2255fb5758321fbac34949, Django 4.2+).

[bmihelac]

Hi Basha,

I have created minimum app

​https://github.com/bmihelac/django-34488

credentials are admin:test

Please note that app behaves differently in Django 4.1.x and Django 4.2.x (as you can see on screencast below or try yourself). Django 4.2 still forget clear checkbox, but at least checkbox is shown.

https://code.djangoproject.com/attachment/ticket/34488/django41-c.webm
https://code.djangoproject.com/attachment/ticket/34488/django42-c.webm

let me know if anything else is needed

[bmihelac]

Replying to Mariusz Felisiak:

Duplicate of #19215 (fixed in c0fc1b5302f5d9d82e2255fb5758321fbac34949, Django 4.2+).

It still forgot Clear choice on validation error in Django 4.2 (this is visible in https://code.djangoproject.com/attachment/ticket/34488/django42-c.webm screencast)

[Mariusz Felisiak]

Replying to bmihelac:

Replying to Mariusz Felisiak:

Duplicate of #19215 (fixed in c0fc1b5302f5d9d82e2255fb5758321fbac34949, Django 4.2+).

It still forgot Clear choice on validation error in Django 4.2 (this is visible in https://code.djangoproject.com/attachment/ticket/34488/django42-c.webm screencast)

"Clear" is always unchecked, I'm not sure if we should change this. Marcelo, what do you think?

[Marcelo Galigniana]

When do a submit and validation error occurs, we persist the "invalid" data in the form. I think keep the checkbox checked would be the same behaviour.

[Mariusz Felisiak]

When do a submit and validation error occurs, we persist the "invalid" data in the form. I think keep the checkbox checked would be the same behaviour.

Agreed. Would you like to prepare a patch?

[Marcelo Galigniana]

Sure!

I see Baha Sdtbekov took the owner 4 days ago. I'm going to assign it to me but in case you already been working on it, please let me know!

Thanks!

[Mariusz Felisiak]

​PR

[Mariusz Felisiak <felisiak.mariusz@…>]

In 8a6c0203:

Fixed #34488 -- Made ClearableFileInput preserve "Clear" checked attribute when form is invalid.

[Mariusz Felisiak <felisiak.mariusz@…>]

In 3d7235c:

Refs #34488 -- Made ClearableFileInput preserve "Clear" checked attribute when form is invalid.