Django test for un-run migtraionts

tests.py

'''
It's worth noting that we use the built-in User model, but also have a tweak that enforces email
uniqueness (which IMO is a pretty large oversight by the django folks), so that's why it's acceptable
that `Migrations for 'auth'` is in the payload. 
'''
class TestForNonGeneratedMigrations(TestCase):
    def test_for_migrations_to_run(self):
        stdout = StringIO.StringIO()

        call_command('makemigrations', no_color=True, dry_run=True, stdout=stdout)

        # If we have any lines that begin with "Migrations for" that are *not* for the django 'auth' app (since we
        # have a custom tweak to the model to enforce email uniqueness), then blow up.
        unrun_migrations = []
        for line in stdout.getvalue().split('\n'):
            if line.startswith('Migrations for') and "Migrations for 'auth'" not in line:
                unrun_migrations.append(line)
        self.assertEqual(len(unrun_migrations), 0)