Using label_from_instance on ModelChoiceField requires resetting queryset first

[mbehm]

The part in the following old issue about having to reset queryset for the label_from_instance to work is valid, even if you follow the documentation to the letter your custom version of label_from_instance won't be called unless you also define the queryset, even if the queryset would be the default.

https://code.djangoproject.com/ticket/6839

[Mariusz Felisiak]

I'm sorry but I don't see anything new in your description. As far as I'm aware you don't need do "reset" a queryset when subclassing ModelChoiceField as documented, e.g.

from django.forms import ModelChoiceField

class MyModelChoiceField(ModelChoiceField):
    def label_from_instance(self, obj):
        return "My Object #%i" % obj.id

class Aform(forms.Form):
    user = MyModelChoiceField(queryset=User.objects.all())

Duplicate of #6839.