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iOS: Migrate the unit test host app to UIScene - #190646
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This pull request configures the iOS unit tests to support the UIScene lifecycle by introducing a SceneDelegate, updating Info.plist, and modifying window initializations to use the connected window scene. The review feedback recommends explicitly stopping class mocks in FlutterPluginAppLifeCycleDelegateTest to prevent test pollution, and adding non-nil assertions for the retrieved window scenes in FlutterViewControllerTest and FlutterViewTest to avoid cryptic test failures.
Apps that haven't adopted the UIScene life cycle will not launch on iOS
27. The `IosUnitTests` host app was still using the pre-scene
`UIApplicationMain` plus `UIMainStoryboardFile` setup, and
failed with
"Early unexpected exit ... The test runner crashed before establishing connection"
when run with on an iOS 27 simulator.
This adds a `UIApplicationSceneManifest` to the host app's `Info.plist`
and a `SceneDelegate`.
Migrating to scenes changes a couple things the tests were relying on.
`FlutterSharedApplication.hasSceneDelegate` now returns `YES` in the
host app, which suppresses forwarding of app lifecycle notifications to
plugins. The `FlutterPluginAppLifeCycleDelegate` tests covering the
pre-migration case stub this back out to `NO`.
`[[UIWindow alloc] init]` no longer picks up a window scene so the
window no longer has a screen. There were a few tests that need a
screen, which now build their window with `initWithWindowScene:`
instead. Without this we trip an `FML_DCHECK(self.screen)` in
`FlutterView isWideGamutSupported]`. I'll send a followup to handle this
more gracefully.
Issue: flutter#188336
The tests that build their own window now assert that the host app has a connected scene before using it. Passing a nil scene to `initWithWindowScene:` produces a window with no screen. This shows up as either an `FML_DCHECK(self.screen)` abort or an unexplained missing `surfaceUpdated:` call rather than pointing at the missing scene.
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Apps that haven't adopted the UIScene life cycle will not launch on iOS
27. The
IosUnitTestshost app was still using the pre-sceneUIApplicationMainplusUIMainStoryboardFilesetup, and failed withwhen run with on an iOS 27 simulator.
This adds a
UIApplicationSceneManifestto the host app'sInfo.plistand aSceneDelegate.Migrating to scenes changes a couple things the tests were relying on.
FlutterSharedApplication.hasSceneDelegatenow returnsYESin the host app, which suppresses forwarding of app lifecycle notifications to plugins. TheFlutterPluginAppLifeCycleDelegatetests covering the pre-migration case stub this back out toNO.[[UIWindow alloc] init]no longer picks up a window scene so the window no longer has a screen. There were a few tests that need a screen, which now build their window withinitWithWindowScene:instead. Without this we trip anFML_DCHECK(self.screen)inFlutterView isWideGamutSupported]. I'll send a followup to handle this more gracefully.Issue: #188336
Pre-launch Checklist
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