Stacktrace recovery doesn't work for suspend main

[opensource21]

I took the example https://raw.githubusercontent.com/Kotlin/kotlinx.coroutines/master/kotlinx-coroutines-debug/test/RecoveryExample.kt and add at line 16 a println("${Thread.currentThread().name}"), so I get

package example

import kotlinx.coroutines.CoroutineName
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.async

object PublicApiImplementation : CoroutineScope by CoroutineScope(CoroutineName("Example")) {

    private fun doWork(): Int {
        error("Internal invariant failed")
    }

    private fun asynchronousWork(): Int {
        println("${Thread.currentThread().name}")
        return doWork() + 1
    }

    public suspend fun awaitAsynchronousWorkInMainThread() {
        val task = async(Dispatchers.Default) {
            asynchronousWork()
        }

        task.await()
    }
}

suspend fun main() {
    // Try to switch debug mode on and off to see the difference
    PublicApiImplementation.awaitAsynchronousWorkInMainThread()
}

I run it with

1. -ea
2. -Dkotlinx.coroutines.debug -Dkotlinx.coroutines.stacktrace.recovery=true
3. -Dkotlinx.coroutines.debug

I never get an recovered stacktrace. How ever I got
DefaultDispatcher-worker-1 @Example#1
so -Dkotlinx.coroutines.debug seems to work.

What does I'm missing?
Here my version
kotlin 1.3.41
coroutines.version 1.2.2

[qwwdfsad]

Thanks for the report!
It appears like a missing recovery in one of the await branches, will investigate further

[opensource21]

@qwwdfsad do you know a version where it works. Would be nice to see this feature in action.

[opensource21]

I looked in org/jetbrains/kotlinx/kotlinx-coroutines-core/1.2.2/kotlinx-coroutines-core-1.2.2-sources.jar!/commonMain/JobSupport.kt:1131. It seems that the state Empty{Active} isn't the expected one.

[qwwdfsad]

@opensource21 it works in the latest version except for your particular case (with suspending await).
I will fix your problem in 1.3.0

[qwwdfsad]

As a workaround, you can use fun main() = runBlocking { ... } instead of suspend fun main()

[opensource21]

If you clone https://gitlab.com/ppiag/zulipbot, rename application.properties.sample to application.properties and replace zulip.url=https://####.zulipchat.com with zulip.url=https://www.zulipchat.com and start BotRunner , I guess you have a different situation with ktor and it doesn't work. Unfortunately it's not so easy to debug :-(

Any idea when 1.3 will be released or a beta for a test?