Jetpack Compose release version: 1.0.0
Android Studio Build: Arctic Fox
Kotlin version: 1.5.30

Previously with plain XML UIs, one was able to test ViewModel and UI (Fragment/Activity + XML) in combination. With Compose and the AndroidComposeTestRule this is no longer possible:

The AndroidComposeTestRule needs a test rule that provides an Activity to the underlying compose infrastructure, while one can give it a FragmentScenarioRule the fragment part of this cannot actually be re-used and the content of the whole Activity is replaced by the Compose UI.
Effectively any code that runs before or after the ComposeView.setContent() of the Fragment (or Activity, for that matter) isn't run when the AndroidComposeTestRule's setContent is used instead. Even worse, depending on the lifecycle state in which an Activity is in (in which state it is started), a previous rendering could or could not have happened, leading to possible side effects with an actual ViewModel interfacing implementation.
I fail to see a way how one could test a partial compose / partial XML layout, where ComposeView is not the root view of the controller component.

I understand that a special Recomposer setup and a lot of other custom tooling is needed to make Jetpack Compose testable in an Robolectric / Android Instrumentation test, however I wish the test architecture would first and foremost provide an API to hook in / replace the existing functionality, e.g. by making it easy to inject a custom test composer in a running fragment / activity instance or by at least making this composer and possibly other utilities available for certain testing purposes.