Set<List<Integer>> degenerate = cartesianProduct();
    checkHashCode(degenerate);

    checkHashCode(cartesianProduct(set(1, 2)));

    int num = Integer.MAX_VALUE / 3 * 2; // tickle overflow-related problems
    checkHashCode(cartesianProduct(set(1, 2, num)));

    Set<Integer> mt = emptySet();
    checkHashCode(cartesianProduct(mt, mt));
    checkHashCode(cartesianProduct(mt, set(num)));

    assertThat(cartesianProduct(list(1), list(2))).contains(list(1, 2));
  }

  public void testCartesianProduct_binary1x2() {
    assertThat(cartesianProduct(list(1), list(2, 3)))
        .containsExactly(list(1, 2), list(1, 3))
        .inOrder();
  }

  public void testCartesianProduct_binary2x2() {
    assertThat(cartesianProduct(list(1, 2), list(3, 4)))

    assertThat(cartesianProduct(list(1), list(2))).contains(list(1, 2));
  }

  public void testCartesianProduct_binary1x2() {
    assertThat(cartesianProduct(list(1), list(2, 3)))
        .containsExactly(list(1, 2), list(1, 3))
        .inOrder();
  }

  public void testCartesianProduct_binary2x2() {
    assertThat(cartesianProduct(list(1, 2), list(3, 4)))

   *     a provided list is null
   * @since 19.0
   */
  @SafeVarargs
  public static <B> List<List<B>> cartesianProduct(List<? extends B>... lists) {
    return cartesianProduct(Arrays.asList(lists));
  }

  /**
   * Returns a list that applies {@code function} to each element of {@code fromList}. The returned