unique_with nullable foreign key

[Bouke Haarsma]

Say I have an AutoSlugField(populated_from='title', unique_with='some_relation') and some_relation has null=True. Now the following scenario hold:

1. title='Hello', some_relation=(1), slug becomes hello
2. title='Hello', some_relation=(2), slug becomes hello
3. title='Hello', some_relation=None, slug becomes hello-2

The third slug should also hello, as it is unique within all some_relation=None.

[dteskera]

something like this may help in autoslug/utils.py around line 113 change this code

        if not value:
            if other_field.blank:
                break

to this

        if not value:
            if other_field.blank:
                from django.db.models import ForeignKey
                field_object, model, direct, m2m = instance._meta.get_field_by_name(field_name)
                if isinstance(field_object, ForeignKey):
                    lookup = '%s__isnull' % field_name
                    yield lookup, True
                break

[Andy]

Solved by @dteskera in PR#8