docs: static void copyBits(CircularBitSet left, CircularBitSet right) {
      int bitsToCopy = Math.min(left.occupiedBits, right.size);
      int index = left.nextIndex - bitsToCopy;
      if (index < 0)
        index += left.occupiedBits;
      for (int i = 0; i < bitsToCopy; i++, index = left.indexAfter(index))
        right.setNext(left.bitSet.get(index));
    }