All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Swearing to do something by making divorce dependent on failing to fulfill what a husband has sworn to do is a type of conditional divorce. If the husband failed to fulfill what he had sworn to do this divorce is effective, according to the view of the majority of the scholars.
Allaah Knows best.