def test_iadd(self, evt):
        rval = event.ReturnValue(append_events=[evt])
        rval2 = event.ReturnValue(eat=True, append_events=[evt])
        rset = event.ResultSet()

        rset += rval
        rset += rval2
        rset += None
        assert rset.eat
        assert rset.append_events == [evt, evt]
def delete_category(category_id):
    category = Category.query.filter_by(id=category_id).first_or_404()

    involved_users = User.query.filter(Forum.category_id == category.id,
                                       Topic.forum_id == Forum.id,
                                       Post.user_id == User.id).all()

    category.delete(involved_users)
    flash(_("Category with all associated forums deleted."), "success")
    return redirect(url_for("management.forums"))