How do Calvinists reconcile Christ's election of Judas Iscariot to be a disciple only to be betrayed by him?

[*Britannica* article on Calvinism](https://www.britannica.com/topic/Calvinism) states > Calvin had certain approximate and attainable tests. He did not > require the experience of the new birth, which is so inward and > intangible, though to be sure later Calvinism moved away from him on > this point and agonized over the signs of election. For Calvin there > were three tests: the profession of faith; a rigorously disciplined > Christian deportment; and a love of the sacraments, which meant the > Lord’s Supper, since infant baptism was not to be repeated. Persons > who could meet these three tests could assume their election and stop > worrying If Christ chose Judas to be a disciple, and if Christ is part of the Trinitarian Godhead being all-knowing and omnipotent... According to Calvinism, how is it that Christ elected Judas Iscariot to discipleship, one of Christ's inner circle, only to be betrayed by him? Calvinists would say Jesus predetermined Judas election to the discipleship because the Bible records he chose him. Because God chose Judas, is not a disciple predetermined to be saved? What happened in this example?