Django 1.8 Migrations: AlterField Migration calls default callable for ForeignKey even when no Model Instances Exist

[Dylan Young]

Steps to reproduce:

Create Model

Make migrations

Add FK to model with a callable default that has some side effect (e.g. creating the default instance in the database)

Make migrations

Migrate (or run tests on clean db)

Observe the side effect

I couldn't find this on the Bug Tracker. Is this still an issue in dev branch?

I haven't reproduced in a controlled test, but if this is something that others have observed or think may be an issue, I can look into reproducing cleanly.

If this is the intended behaviour then documentation is needed, though I don't see why it would be since defaults aren't enforced on the DB level.  

Note: it runs cleanly if the default is placed in an AddField migration. 

Best,

Casey Meijer   

[Tim Graham]

Hi, I think the issue is described in https://code.djangoproject.com/ticket/24182.