fix

Code

package com.glassthought.sandbox

import gt.sandbox.util.output.Emojis
import gt.sandbox.util.output.Out
import kotlinx.coroutines.CancellationException
import kotlinx.coroutines.CoroutineName
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.Job
import kotlinx.coroutines.SupervisorJob
import kotlinx.coroutines.async
import kotlinx.coroutines.cancel
import kotlinx.coroutines.coroutineScope
import kotlinx.coroutines.delay
import kotlinx.coroutines.launch
import kotlinx.coroutines.runBlocking
import kotlin.system.exitProcess
import kotlin.time.Duration.Companion.milliseconds

fun main(): kotlin.Unit = runBlocking {
  val out = Out.standard()
  out.info("START")

  try {
    val scope = CoroutineScope(
      Dispatchers.Default
    )

    val deferredLevel1 = scope.launch(CoroutineName("level-1")) {
      coroutineScope {

        val isolatedScope = CoroutineScope(
          coroutineContext + SupervisorJob(coroutineContext[Job])
        )

        val deferred = isolatedScope.async(
          CoroutineName("Cares about cancellation of parent scope")
        ) {
          (0..10)
            .map { "a-${it}" }
            .forEach {
              out.info(it)

              try {
                delay(500)
              } catch (e: CancellationException) {
                val excMsg = e.message ?: e.toString()
                out.warn("${Emojis.OBIDIENT} I have caught [${e::class.simpleName}/$excMsg], and rethrowing it ${Emojis.OBIDIENT} ")

                throw e
              }
            }
        }

        out.delayedActionWithMsg(
          "cancel top level scope",
          action = {
            scope.cancel("Cancelling top level scope - ${Emojis.CANCELLATION}")
          },
          delayBeforeAction = 1500.milliseconds
        )

        out.delayedActionWithMsg(
          "await on deferred",
          action = {
            // This will throw CancellationException, since we cancelled the scope
            out.info("deferred result=" + deferred.await())
          },
          delayBeforeAction = 1500.milliseconds
        )
      }
    }
    deferredLevel1.join()

  } catch (e: Exception) {
    out.error("in main got an exception! of type=[${e::class.simpleName}] with msg=[${e.message}] cause=[${e.cause}]. Exiting with error code 1")

    exitProcess(1)
  }

  out.info("DONE - without errors on main")
}

class MyExceptionWillThrowFromCoroutine(msg: String) : RuntimeException(msg)

Command to reproduce:

gt.sandbox.checkout.commit 5cc712f733a6345c8f05 \
&& cd "${GT_SANDBOX_REPO}" \
&& cmd.run.announce "./gradlew run --quiet"

Recorded output of command:

Picked up JAVA_TOOL_OPTIONS: -Dkotlinx.coroutines.debug
Picked up JAVA_TOOL_OPTIONS: -Dkotlinx.coroutines.debug
[INFO][elapsed:   14ms][🥇][①][coroutname:@coroutine#1][tname:main/tid:1] START
[INFO][elapsed:   36ms][2️⃣][⓶][coroutname:@Cares about cancellation of parent scope#3][tname:DefaultDispatcher-worker-2/tid:32] a-0
[INFO][elapsed:   36ms][3️⃣][⓷][coroutname:@level-1#2][tname:DefaultDispatcher-worker-1/tid:31] [1.5sms delay] before_action=[cancel top level scope]
[INFO][elapsed:  537ms][2️⃣][⓶][coroutname:@Cares about cancellation of parent scope#3][tname:DefaultDispatcher-worker-2/tid:32] a-1
[INFO][elapsed: 1038ms][2️⃣][⓶][coroutname:@Cares about cancellation of parent scope#3][tname:DefaultDispatcher-worker-2/tid:32] a-2
[INFO][elapsed: 1537ms][2️⃣][⓷][coroutname:@level-1#2][tname:DefaultDispatcher-worker-2/tid:32] [Done with=1.5sms delay] performing action=[cancel top level scope]
[INFO][elapsed: 1538ms][3️⃣][⓶][coroutname:@Cares about cancellation of parent scope#3][tname:DefaultDispatcher-worker-1/tid:31] a-3
[INFO][elapsed: 1540ms][2️⃣][⓷][coroutname:@level-1#2][tname:DefaultDispatcher-worker-2/tid:32] performed action=[cancel top level scope]
[INFO][elapsed: 1540ms][2️⃣][⓷][coroutname:@level-1#2][tname:DefaultDispatcher-worker-2/tid:32] [1.5sms delay] before_action=[await on deferred]
[WARN][elapsed: 1585ms][3️⃣][⓶][coroutname:@Cares about cancellation of parent scope#3][tname:DefaultDispatcher-worker-1/tid:31] 🫡 I have caught [CancellationException/Cancelling top level scope - �, and rethrowing it 🫡 
[INFO][elapsed: 1586ms][🥇][①][coroutname:@coroutine#1][tname:main/tid:1] DONE - without errors on main