merge doesn't work for models related with on_delete=Protect about django-adminactions HOT 4 CLOSED

you are right, the issue happen in the "preview" step. Not sure about your solution, as this could cause the form (and the record) will not validate.
I'm going to add the feature to 'skip' the preview and add a note to use it if ProtectedError happen.

from django-adminactions.

Any update on this?

from django-adminactions.

I need this functionality and would be willing to write a PR if it will be merged in. I would like some explanation for this code from the preview step:

with transaction.nocommit():
    form = MForm(request.POST, instance=master)
    other.delete()
form_is_valid = form.is_valid()

I understand you are deleting the other instance, then validating the master model, and then rolling back the transaction. But I do not understand why - why do you need to validate the master instance with the other instance deleted?

from django-adminactions.

the intention is to invoke model validation, and display errors in a proper way. Using a form Django calls full_clean() and validate_unique() on master. This is needed to check that the new instance can be properly saved.

from django-adminactions.