// spliterator is known to be nonempty now
        spliterator.forEachRemaining(state::set);
        return java.util.Optional.of(state.get());
      }

      Spliterator<T> prefix = spliterator.trySplit();
      if (prefix == null || prefix.getExactSizeIfKnown() == 0) {
        // we can't split this any further
        spliterator.forEachRemaining(state::set);
        if (state.set) {

      long size = spliterator.getExactSizeIfKnown();
      if (size > 0) { // known *and* nonempty
        ensureRoomFor(Ints.saturatedCast(size));
      }
      spliterator.forEachRemaining((LongConsumer) this::add);
      return this;
    }

    /**
     * Appends {@code values}, in order, to the end of the values the built {@link
     * ImmutableLongArray} will contain.
     */

      long size = spliterator.getExactSizeIfKnown();
      if (size > 0) { // known *and* nonempty
        ensureRoomFor(Ints.saturatedCast(size));
      }
      spliterator.forEachRemaining((IntConsumer) this::add);
      return this;
    }

    /**
     * Appends {@code values}, in order, to the end of the values the built {@link
     * ImmutableIntArray} will contain.
     */