id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
23574	Makemigrations tries to migrate non-model classes	Christian Peters	nobody	"If your model extends non-model classes, the migration fails with:

    raise ValueError(""Cannot serialize: %r\nThere are some values Django cannot serialize into migration files.\nFor more, see https://docs.djangoproject.com/en/dev/topics/migrations/#migration-serializin

The reason is that before adding the base classes there is no check if the base class is indeed a django model:

https://github.com/django/django/blob/master/django/db/migrations/autodetector.py#L495-505

Solution: Check if the base class is an instance of django.db.model before adding it.

Context:

I have Models with some mixins that just add method and functionality that is shared among multiple models, e.g. an InvoiceMixin, that is shared by multiple models to enrich them with convenience methods."	Bug	closed	Migrations	1.7	Normal	invalid			Unreviewed	0	0	0	0	0	0