List<Object> exp4 = list((Object) 2, "4");

    assertThat(Lists.<Object>cartesianProduct(x, y))
        .containsExactly(exp1, exp2, exp3, exp4)
        .inOrder();
  }

  public void testCartesianProductTooBig() {
    List<String> list = nCopies(10000, "foo");
    assertThrows(
        IllegalArgumentException.class, () -> cartesianProduct(list, list, list, list, list));
  }