I have a function something like

suspend fun <T : Any> request(target: APITarget, responseDeserializer: DeserializationStrategy<T>, response: (NetworkResult) -> Unit): Cancelable

How do I test this? Wait till the response lamda completes and cross verify the result. Putting the test inside runblocking doesn’t work.

When testing stuff like that I know a hacky way that works most of the time. If you use this class

class CoroutineLock() {
    private var channel by AtomicReferenceDelegate<ConflatedBroadcastChannel<Unit>?>(null)

    private val mutex = Mutex()
    val isLocked: Boolean get() = channel != null

    suspend fun lock() {
        mutex.withLock {
            val channel = channel ?: ConflatedBroadcastChannel()
            this.channel = channel
            channel.openSubscription().receive()
        }
    }

    fun unlock() {
        channel?.offer(Unit)
        channel = null
    }
}

With the AtomicReferenceDelegate being a simple ReadWriteProperty around AtomicReference to avoid mutation crashes on native. It works like the JVM

wait()

and

notify()

functions on Object. You can use this to synchronise your code the way you need to

Would have thought a

CompletableDeferred<NetworkResult>

was more appropriate:

val result = CompletableDeferred<NetworkResult>()
launch { request(target, deser) { result.complete(it) } }
result.await()

I agree a CompletableDeferred would be a better option

Yeah, Could be a wrong approach. I’m new to kotlin and kmm. Open to learning it correct way. I understand how suspend functions can return the result directly. But I don’t understand how to “registering its cancellation handle with the coroutine context?” Would be very grateful if you could point be towards an example. Basically these are network requests and I would like to have the ability to cancel them. @araqnid

Here’s an example of how I adapted an async http client to a suspend function: https://github.com/araqnid/fuel-log/blob/3f805eeec3035faae369dfe6f9f1f69179828cac/[…]rc/main/kotlin/org/araqnid/fuellog/AsyncHttpClientExtensions.kt

Also make sure you check for cancellation @sushma nayak, you don't do it in your example @araqnid, it might not be important for your use case but it could be for others

suspendCancellableCoroutine

is \m/ It seems to be working. Thank you @Benoît and @araqnid 😄 People like you in the community make newbies like me survive in the platform. Could otherwise drive us away with frustration.

Glad you figured it out. And no worries, we're all someone's noob here :)