[newforms-admin] defaults for ManyToManyFields are broken on add page

[John Shaffer]

In trunk, /app/model/add/?options=12, where options is a ManyToManyField, works as expected: the Option with a pk of 12 is selected. In newforms-admin, it is interpreted as if the querystring had been options=1,2: the Options with pks of 1 and 2 are selected.

[Ivan Giuliani]

The problem described here belongs to this line: ​http://code.djangoproject.com/browser/django/trunk/django/contrib/admin/options.py#L501
Actually, the initial_data for model forms on SelectMultipleWidget expects an iterable object like a list or tuple for selecting the choices, while instead we're passing a string - i.e. "12" - that get then divided in in "1" and "2". I thought this could be changed in something like string.split(',') but I can see this behaviour is not documented anywhere, so maybe some core dev has a better idea (or maybe this should be marked as wontfix?).

[Ivan Giuliani]

Just a note here since probably I was a bit drunk when I wrote the comment above: the widget is SelectMultiple obviously and what expects an iterable object is the choices attribute of render().

[Jacob]

(In [8699]) Fixed #7738: support initial values via GET for SelectMutliple in the admin.

[gkelly]

Patch for when exception is caught, f would be undefined.

[gkelly]

Undefined f fixed in [8714]

[Jacob]

Milestone 1.0 deleted