What is the ruling on one who swore an oath of self-malediction upon herself not to joke with her husband, then she joked with him?

It is not permissible for a Muslim to invoke evil upon himself, or to curse himself or others, due to the Prophet's (peace be upon him) prohibition of invoking evil upon oneself, one's children, or one's wealth. He also said: "The believer is not a slanderer nor a curser." The wife's jest does not affect the marital bond, and there is no expiation for it except repentance to Allah the Almighty.