def METHOD_NAME(self, index_addons_mock):
    collection = Collection.objects.create(author=self.user, slug='foo')
    addon = addon_factory()
    index_addons_mock.reset_mock()
    collection.add_addon(addon)
    assert index_addons_mock.call_count == 0
    collection = Collection.objects.create(
        author=self.user, slug='featured', id=settings.COLLECTION_FEATURED_THEMES_ID
    )
    addon_featured = addon_factory()
    index_addons_mock.reset_mock()
    collection.add_addon(addon_featured)
    assert collection.addons.count() == 1
    assert index_addons_mock.call_count == 1
    assert index_addons_mock.call_args[0] == ([addon_featured.pk],)