List<List<Integer>> partitions = Lists.partition(source, 2);

    assertTrue(
        "partition should be RandomAccess, but not: " + partitions.getClass(),
        partitions instanceof RandomAccess);

    assertTrue(
        "partition[0] should be RandomAccess, but not: " + partitions.get(0).getClass(),
        partitions.get(0) instanceof RandomAccess);

    assertTrue(

    List<List<Integer>> partitions = Lists.partition(source, 2);

    assertTrue(
        "partition should be RandomAccess, but not: " + partitions.getClass(),
        partitions instanceof RandomAccess);

    assertTrue(
        "partition[0] should be RandomAccess, but not: " + partitions.get(0).getClass(),
        partitions.get(0) instanceof RandomAccess);

    assertTrue(

    Iterator<List<Integer>> partitions = Iterators.partition(source, 1);
    assertTrue(partitions.hasNext());
    assertTrue(partitions.hasNext());
    assertEquals(ImmutableList.of(1), partitions.next());
    assertFalse(partitions.hasNext());
  }

  public void testPartition_singleton2() {
    Iterator<Integer> source = Iterators.singletonIterator(1);

   * <p><b>Note:</b> if {@code iterable} is a {@link List}, use {@link Lists#partition(List, int)}
   * instead.
   *
   * @param iterable the iterable to return a partitioned view of
   * @param size the desired size of each partition (the last may be smaller)
   * @return an iterable of unmodifiable lists containing the elements of {@code iterable} divided
   *     into partitions
   * @throws IllegalArgumentException if {@code size} is nonpositive

    Iterable<List<Integer>> partitions = Iterables.partition(source, 1);
    assertEquals(1, Iterables.size(partitions));
    assertEquals(Collections.singletonList(1), partitions.iterator().next());
  }

  public void testPartition_view() {
    List<Integer> list = asList(1, 2);
    Iterable<List<Integer>> partitions = Iterables.partition(list, 2);

    // Changes before the partition is retrieved are reflected

      }
    }
  }

  /**
   * Partitions the contents of buffer in the range [left, right] around the pivot element
   * previously stored in buffer[pivotValue]. Returns the new index of the pivot element,
   * pivotNewIndex, so that everything in [left, pivotNewIndex] is ≤ pivotValue and everything in
   * (pivotNewIndex, right] is greater than pivotValue.
   */
  private int partition(int left, int right, int pivotIndex) {

    Iterable<List<Integer>> partitions = Iterables.partition(source, 1);
    assertEquals(1, Iterables.size(partitions));
    assertEquals(Collections.singletonList(1), partitions.iterator().next());
  }

  public void testPartition_view() {
    List<Integer> list = asList(1, 2);
    Iterable<List<Integer>> partitions = Iterables.partition(list, 2);

    // Changes before the partition is retrieved are reflected

    Iterator<List<Integer>> partitions = Iterators.partition(source, 1);
    assertTrue(partitions.hasNext());
    assertTrue(partitions.hasNext());
    assertEquals(ImmutableList.of(1), partitions.next());
    assertFalse(partitions.hasNext());
  }

  public void testPartition_singleton2() {
    Iterator<Integer> source = singletonIterator(1);
    Iterator<List<Integer>> partitions = Iterators.partition(source, 2);

   * <p><b>Note:</b> if {@code iterable} is a {@link List}, use {@link Lists#partition(List, int)}
   * instead.
   *
   * @param iterable the iterable to return a partitioned view of
   * @param size the desired size of each partition (the last may be smaller)
   * @return an iterable of unmodifiable lists containing the elements of {@code iterable} divided
   *     into partitions
   * @throws IllegalArgumentException if {@code size} is nonpositive

   */
  public static <T extends @Nullable Object> List<List<T>> partition(List<T> list, int size) {
    checkNotNull(list);
    checkArgument(size > 0);
    return (list instanceof RandomAccess)
        ? new RandomAccessPartition<>(list, size)
        : new Partition<>(list, size);
  }

  private static class Partition<T extends @Nullable Object> extends AbstractList<List<T>> {
    final List<T> list;