Can some1 help me understand when the awaitClose gets called:

@Test
fun `test flow` (): Unit = runBlocking{
    val flow = callbackFlow {
        trySend(Unit)
        delay(5000)
        close()

        awaitClose {
            println("Closed")
        }
    }

    val job = launch {
        flow.collect {  }
    }
    job.cancel()
}

The doc says on close and cancellation. But in this case, it is not called. Why ? When it is cancelled, awaitClose not called.

My guess is that the collector is cancelled when the flow is still in the

delay()

so the flow's body doesn't even have the time to register the

awaitClose

callback, nor to close the underlying channel of the

callbackFlow

. To be fair that's not really how

callbackFlow

is designed to be used (it's rather meant to wrap listener based APIs)

oh ya, you are right! Yes, i know 😛 I just used the delay to try check if the awaitClose really get’s called on cancellation

If you want to test that I suggest you remove the delay and the

close()

call.

awaitClose()

will actually wait for cancellation