Applying a snapshot with animation to UITableViewDiffableDataSource doesn't update the cell

Number:rdar://FB7588509 Date Originated:Feb 19, 2020
Status:Open Resolved:
Product:UIKit Product Version:
Classification:Incorrect/Unexpected Behavior Reproducible:
I attached a sample project to highlight the issue I'm facing with diffable data sources. The app is simple: there's a table view that shows a list of items, and a bar button item that changes the text of the first visible cell. Changes are made by modifying the underlying model, creating a new snapshot and applying it to the data source. When tapping the button you can choose whether or not using animation.

When you don't animate the update, the cell is updated correctly. However when animatingDifferences is true, the cellProvider block in the data source isn't called. If you scroll the table view (making the cell disappear) and go back, the cell shows the updated value.


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!