Coroutines cancellation

LaunchCoroutines.kt

fun main(args: Array<String>) {
    val handler = CoroutineExceptionHandler { context, exception ->
        println("CoroutineExceptionHandler got $exception with suppressed ${exception.suppressed.contentToString()}")
    }
    val parentScope = CoroutineScope(Dispatchers.Default + Job() + handler)
//    val parentScope = MyScope()

    parentScope.launch {
        println("one job: " + this.coroutineContext[Job].toString())
        println("Hello")
        delay(800)
//        try {
            throw NullPointerException("faiiiil")
//        } catch (e: Exception) {
//            cancel("cancelled 1")
//        }
        println("World")
    }

    parentScope.launch {
        delay(1500)
        this.coroutineContext.ensureActive()
        println("Sibling job")
    }

    val input = readLine()
    println("Your input was $input")

    parentScope.launch {
        println("third job")
    }
}

MyScopeCoroutines.kt

class MyScope: CoroutineScope {
    private val handler = CoroutineExceptionHandler { context, exception ->
        println("CoroutineExceptionHandler got $exception with suppressed ${exception.suppressed.contentToString()}")
    }

    override val coroutineContext: CoroutineContext
        get() = Dispatchers.Default + Job() + handler

    fun run() {
        launch {
            println("one job: " + this.coroutineContext[Job].toString())
            println("Hello")
            delay(800)
//            try {
                throw NullPointerException("faiiiil")
//            } catch (e: Exception) {
//                cancel("cancelled 1")
//            }
            println("World")
        }

        launch {
            delay(1500)
            this.coroutineContext.ensureActive()
            println("Sibling job")
        }

        val input = readLine()
        println("Your input was $input")

        launch {
            println("third job")
        }
    }
}

fun main(args: Array<String>) {
    MyScope().run()
}