Endless join of waitChildrenCompletion with TestViewModelScopeRule

[Tetraquark]

If some inheritor of ViewModel has any endless collectors of Flow (e.g. launch coroutine in init block for some Flow from abstract repository or collect data using extension asLiveData from moko-mvvm), then waitChildrenCompletion will start endless join of that endless collector coroutines. So, the test will never end.

[Tetraquark]

Workaround using withTimeout:

fun CoroutineScope.waitChildrenCompletion() = runBlocking {
    val job = this@waitChildrenCompletionWithTimeout.coroutineContext[Job]
    val children = job?.children.orEmpty().toList()
    children.forEach {
        try {
            withTimeout(100) {
                it.join()
            }
        } catch (timeOutEx: TimeoutCancellationException) {}
    }
}