Iterator<List<Integer>> partitions = Iterators.partition(source, 2);
    assertTrue(partitions.next() instanceof RandomAccess);
    assertTrue(partitions.next() instanceof RandomAccess);
  }

  public void testPaddedPartition_badSize() {
    Iterator<Integer> source = singletonIterator(1);
    assertThrows(IllegalArgumentException.class, () -> Iterators.paddedPartition(source, 0));
  }

  public void testPaddedPartition_empty() {