Update docs example code for ModelAdmin.save_formset()

[Carsten Fuchs]

Currently, the example code for ​ModelAdmin.save_formset() is:

class ArticleAdmin(admin.ModelAdmin):
    def save_formset(self, request, form, formset, change):
        instances = formset.save(commit=False)
        for instance in instances:
            instance.user = request.user
            instance.save()
        formset.save_m2m()

In the text, there is a link to ​https://docs.djangoproject.com/en/1.8/topics/forms/modelforms/#saving-objects-in-the-formset, but not to ​https://docs.djangoproject.com/en/1.8/topics/forms/formsets/#can-delete, where it is mentioned that with Django 1.7, formset.save(commit=False) no longer deletes objects automatically.

(This is also mentioned in the ​Django 1.7 Release Notes, but for me at least, this was not enough to make the required mental leap...)

Thus, I suggest to augment the above example code as follows:

docs/ref/contrib/admin/index.txt

@@ -1259 +1259 @@
         class ArticleAdmin(admin.ModelAdmin):
             def save_formset(self, request, form, formset, change):
                 instances = formset.save(commit=False)
+                for obj in formset.deleted_objects:
+                    obj.delete()
                 for instance in instances:
                     instance.user = request.user
                     instance.save()

[Baptiste Mispelon]

That makes sense.

Could you submit your proposed change as a pull request?

Thanks.

[Tim Graham <timograham@…>]

In e15c55e2:

Fixed #24668 -- Amended ModelAdmin.save_formset() example for #10284.

Thanks Carsten Fuchs.

[Tim Graham <timograham@…>]

In 32871fc:

[1.7.x] Fixed #24668 -- Amended ModelAdmin.save_formset() example for #10284.

Thanks Carsten Fuchs.

Backport of e15c55e2bf5eb2f1073d18b4ee6fdce2369820f2 from master

[Tim Graham <timograham@…>]

In e02616b:

[1.8.x] Fixed #24668 -- Amended ModelAdmin.save_formset() example for #10284.

Thanks Carsten Fuchs.

Backport of e15c55e2bf5eb2f1073d18b4ee6fdce2369820f2 from master