"Save as new" does not work when a ValidationError is raised

[cauley.chris@…]

We use save_as = True for several of our models on a news site I maintain. Each model has a unique "slug" field. If you press "Save as New" without changing the slug field a ValidationError is raised, and the for is displayed to the user with a warning (as it should). However, the url is that of the old entity, the "Save as New" button is replaced with "Save and Add Another" and all three buttons raise an ValueError (trying to int() an empty string, presumably the id).

[anonymous]

Duplicate of #13223. See also #5681.

[Ramiro Morales]

(sorry, anonymous user above was me)

Wait, the OP doesn't mention inlines so this isn't a duplicate of #13223.

But I can't reproduce the reported error with this simple model

class Article(models.Model):
    title = models.CharField(max_length=30)
    slug = models.CharField(max_length=200, unique=True)

    def __unicode__(self):
        return self.title

and ModelAdmin

class ArticleAdmin(admin.ModelAdmin):
    save_as = True


admin.site.register(Article, ArticleAdmin)

(tested this with 1.3 and trunk)

[Gregor Müllegger]

This bug is valid, and I have a proof for that :) (see attached testcase).

The form is not showing the "save as new" button after a form validation occured. The reason is pretty simple:

The "save as new" button is only shown on "change_view" pages (which makes sense), see ​https://github.com/django/django/blob/master/django/contrib/admin/templatetags/admin_modify.py#L32 …

… however here …
​https://github.com/django/django/blob/master/django/contrib/admin/options.py#L1025
… is the "add_view" called when the object is saved, using the "save as new" button.

[Gregor Müllegger]

Failing testcase.

[Hiroki Kiyohara]

I added a patch to fix this bug.

It changes to call add_view when the form is valid and "_saveasnew" in request.POST.
The form is not valid, it operates as same the normal "save" behavior.

The gregmuellegger's test patch can't be used as it is.
What do you say about this behavior?

[Tim Graham]

Duplicate of #23387 which has been fixed in master (1.9) by only showing the "Save as new" button if it's selected and there are validation errors.