assertThat(
            concat(megaPrimitiveDoubleStreamPart1(), megaPrimitiveDoubleStreamPart2())
                .sorted()
                .toArray())
        .isEqualTo(megaPrimitiveDoubleStream().toArray());
  }

  public void testAddAllPrimitiveDoubleStream() {
    StatsAccumulator accumulator = new StatsAccumulator();
    accumulator.addAll(megaPrimitiveDoubleStreamPart1());