docs: @Pure
  	public int indexOf(BusItineraryHalt bushalt) {
  		if (bushalt == null) {
  			return -1;
  		}
  		if (bushalt.isValidPrimitive()) {
  			return ListUtil.indexOf(this.validHalts, VALID_HALT_COMPARATOR, bushalt);
  		}
  		int idx = ListUtil.indexOf(this.invalidHalts, INVALID_HALT_COMPARATOR, bushalt);
  		if (idx >= 0) {
  			idx += this.validHalts.size();
  		}
  		return idx;
  	}