Attempt to set a many to many relation throws exception unless model specifies ordering.

[jforeman@…]

I've got two basic models, with a ManyToManyField connecting them. An exception is thrown while trying to set the relation:

class Foo(meta.Model)
    fields = (
        meta.CharField('name', 'name', maxlength=100),
    )

class Bar(meta.Model)
    fields = (
        meta.CharField('name', 'name', maxlength=100),
        meta.ManyToManyField(Foo),
    )


>>> f = foos.get_object(id__exact=1)
>>> b = bars.get_object(id__exact=1)
>>> f.set_bars((b.id,))
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/django/core/meta.py", line 57, in _curried
    return args[0](*(args[1:]+moreargs), **dict(kwargs.items() + morekwargs.items()))
  File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/django/core/meta.py", line 897, in method_set_related_many_to_many
    if rel_field.rel.orderable:
AttributeError: ManyToMany instance has no attribute 'orderable'

If I add an "ordering = (('name', 'ASC'),)" to Bar then it works as expected.

The relation should work even without specifying an ordering, however orderable does not seem to be set at all unless I explicitly add ordering to the model.

[jforeman@…]

Actually, it doesn't work even if I set an ordering. I had to edit core/meta.py to remove the check for rel_field.rel.orderable

[Adrian Holovaty]

Fixed in [157]. Thanks for the report! FYI, this was some legacy code from a previous Django incarnation that allowed for orderable many-to-many relations...We dropped support for that a couple of months back.