Dismissing multiple sheets to present different sheet freezes app #3779
Description
Description
From TCA 1.21.0 there's a regression when dismissing two (probably two or more, but I didn't test this) sheets to present another sheet. While all sheets get dismissed and the other gets presented the app freezes and must be force quit.
This does not happen with TCA 1.20.2 and lower. I can't reproduce it in vanilla SwiftUI or with SwiftUINavigation. It also happens with Perception 1 and TCA main.
The following warnings are in the Xcode console:
Failed to complete already running transition on <_TtGC7SwiftUI29PresentationHostingControllerVS_7AnyView_: 0x12d80f400>.
Trying to dismiss the presentation controller while transitioning already. (<_UIFormSheetPresentationController: 0x10292e510>)
This happens with Xcode 26 and iOS 26 (device, sim). I didn't test other Xcode or iOS versions so far.
You can find my sample with TCA, SwiftUINav and vanilla attached to test it yourself.
Checklist
- I have determined whether this bug is also reproducible in a vanilla SwiftUI project.
- If possible, I've reproduced the issue using the
mainbranch of this package. - This issue hasn't been addressed in an existing GitHub issue or discussion.
Expected behavior
Sheets get dismissed, new sheet gets presented. App does not freeze.
Actual behavior
Sheets get dismissed, new sheet gets presented. App freezes.
Reproducing project
The Composable Architecture version information
1.21.0
Destination operating system
iOS 26
Xcode version information
Xcode 26
Swift Compiler version information
swift-driver version: 1.127.14.1 Apple Swift version 6.2 (swiftlang-6.2.0.19.9 clang-1700.3.19.1)
Target: arm64-apple-macosx15.0