Is there a way to `cancelAllChildren` of a `runTest` scope? I have a test where I inject the test `c...

# coroutines

[Lukasz Kalnik]

Is there a way to cancelAllChildren of a runTest scope?
I have a test where I inject the test coroutineContext into a ViewModel and I want to cancel all running jobs inside the ViewModel when the test ends.

[Lukasz Kalnik]

class MyViewModel(coroutineContext: CoroutineContext = Dispatchers.Default) : ViewModel() {
    
    private val coroutineScope = viewModelScope + coroutineContext

    init {
        coroutineScope.launch { myFlow.collect { /* do something with collected items */ } }
    }
}

class MyViewModelTest {

    @Test
    fun testInitMyViewModel() = runTest {
        MyViewModel(coroutineContext) // coroutineContext from test injected here
        // test hangs and times out eventually because myFlow collection is not canceled
    }
}

[Trevor Stone]

val job = Job()
val coroutineContext: CoroutineContext = coroutineContext + job

job.cancel()

might work

[Lukasz Kalnik]

Yup, works perfectly! Thanks for a quick and helpful answer.

[Lukasz Kalnik]

If only it could be somehow automatized...

[Lukasz Kalnik]

Doesn't coroutineContext already have a Job which I could reuse?

[Paul Woitaschek]

You can call into the children

[Lukasz Kalnik]

How?

[Paul Woitaschek]

Sth like coroutineContext[Job].children().forEach it cancel

[Paul Woitaschek]

Coding on my phone ;-)

[Lukasz Kalnik]

Thanks, that works!

[Lukasz Kalnik]

The part I was missing was the coroutineContext[Job] key!

[Lukasz Kalnik]

Thank you so much for your help ❤️

[Paul Woitaschek]

🤗 welcome

[Lukasz Kalnik]

You can even do

coroutineContext[Job]?.cancelChildren()