UICollectionView Lists and targetIndexPathForMoveFromItemAt

I'm trying to implement row reordering with the new reorderingHandlers. Some of the items in my CollectionView-OutlineView can only be dropped to certain destinations.

I'm attempting to implement targetIndexPathForMoveFromItemAt to provide correct destination IndexPaths.

I'm observing that the originalIndexPath for an item that's being reordered appears to change during the life of the drag in an outline view.

It almost seems that originalIndexPath follows the value of the proposedIndexPath during the life of the drag.

This makes it difficult to determine valid drop locations for different types of items in the outline view.

Example output of originalIndexPath and proposedIndexPath (without letting go and letting the move proceed)
PROPOSE MOVING SOURCE AT: [3, 1] TO [[3, 1]]
PROPOSE MOVING SOURCE AT: [3, 1] TO [[3, 0]]
PROPOSE MOVING SOURCE AT: [3, 0] TO [[3, 1]]
PROPOSE MOVING SOURCE AT: [3, 1] TO [[3, 0]]
PROPOSE MOVING SOURCE AT: [3, 0] TO [[3, 0]]

I expect the proposedIndexPath to change as I move through the list, but the originalIndexpath changing surprised me.

UICollectionView Lists and targetIndexPathForMoveFromItemAt
 
 
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