If in any case a continuance be asked because of the absence of a witness, an affidavit must be filed, if required by any party opposing, setting forth, in addition to other matters required in order to obtain a continuance, the name of the witness and the testimony he is expected to give, and the affiant must, if required by any opposing party, submit to cross- examination in open court upon the matters set forth in such affidavit.
West Virginia Legal Code