UICollectionView animate data change

Question

Wrapping -reloadData in -performBatchUpdates: does not seem to cause a one-section collection view to animate.

[self.collectionView performBatchUpdates:^{
    [self.collectionView reloadData];
} completion:nil];

However, this code works:

[self.collectionView performBatchUpdates:^{
    [self.collectionView reloadSections:[NSIndexSet indexSetWithIndex:0]];
} completion:nil];