Crash/Freeze in UICollectionView.performBatchUpdates when Removing Header

Originator:milkservice
Number:rdar://43610684 Date Originated:2018-08-22
Status:Open Resolved:
Product:iOS + SDK UIKit Product Version:Xcode 9.4.1 / 10 beta 6
Classification:Crash/Hang/Data Loss Reproducible:Always
 
Summary:


Steps to Reproduce:
* Check out https://github.com/fabb/CollectiveCrash
* Run the project
* Remove the only collectionview item via the "Remove" bar button

Expected Results:
* The last item should be removed, also the header should be removed

Actual Results:
* On Xcode 9 with iOS 11.4 simulator, the app crashes
* On Xcode 10 beta 6 with iOS 12 simulator, the app freezes for 15 seconds (!!), then continues normally

Version/Build:
Xcode 9.4.1 and 10 beta 6 respectively

Configuration:
iOS simulators bundled with respective Xcode versions

Comments


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