scratch.kts

import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Job
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.flow.collect
import kotlinx.coroutines.flow.flow
import kotlinx.coroutines.flow.flowOn
import kotlinx.coroutines.launch
import kotlinx.coroutines.runBlocking
import kotlinx.coroutines.withContext
import kotlin.coroutines.CoroutineContext

class Sample(override val coroutineContext: CoroutineContext) : CoroutineScope {

    fun foo() =
        launch {
            println("1. launched foo @ $coroutineContext")
            val flow = flowFoo()
            flow.collect {
                println("3-5. collected flowFoo @ $coroutineContext, value: $it")
            }
        }

    fun fooIo() =
        launch(Dispatchers.IO) {
            println("1. launched fooIo  @ $coroutineContext")
            val flow = flowFoo()
            flow.collect {
                println("3-5. collected flowFoo @ $coroutineContext, value: $it")
            }
        }

    fun fooWithContext() =
        launch {
            println("1. launched fooWithContext  @ $coroutineContext")
            val flow = withContext(Dispatchers.IO) { flowFoo() }
            flow.collect {
                println("3-5. collected flowFoo @ $coroutineContext, value: $it")
            }
        }

    @ExperimentalCoroutinesApi
    fun fooWithFlowOn() =
        launch {
            println("1. launched fooWithFlowOn  @ $coroutineContext")
            val flow = flowFoo().flowOn(Dispatchers.IO)
            flow.collect {
                println("3-5. collected flowFoo @ $coroutineContext, value: $it")
            }
        }

    @ExperimentalCoroutinesApi
    fun fooWithFlowOnOuter(): Job {
        val flow = flowFoo().flowOn(Dispatchers.IO)
        return launch {
            println("1. launched fooWithFlowOnOuter  @ $coroutineContext")
            flow.collect {
                println("3-5. collected flowFoo @ $coroutineContext, value: $it")
            }
        }
    }

    fun flowFoo() = flow {
        println("2. called flowFoo @ $coroutineContext")
        emit(100)
        emit(200)
        emit(300)
        println("6. emitted flow foo @ $coroutineContext")
        println("7. completed flow foo @ $coroutineContext")
    }
}

fun main() = runBlocking {
    println("start")
    val sample = Sample(coroutineContext)

    sample.foo().join()
    println("---------")
    sample.fooIo().join()
    println("---------")
    sample.fooWithContext().join()
    println("---------")
    sample.fooWithFlowOn().join()
    println("---------")
    sample.fooWithFlowOnOuter().join()
    println("---------")
}

main()

scratch.kts.out.txt

Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8

scratch.kts:89 1. launched foo @ [StandaloneCoroutine{Active}@32a1bec0, BlockingEventLoop@22927a81]
scratch.kts:89 2. called flowFoo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@32a1bec0, BlockingEventLoop@22927a81], value: 100
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@32a1bec0, BlockingEventLoop@22927a81], value: 200
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@32a1bec0, BlockingEventLoop@22927a81], value: 300
scratch.kts:89 6. emitted flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 7. completed flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 ---------
scratch.kts:89 1. launched fooIo  @ [StandaloneCoroutine{Active}@73cd03d9, LimitingDispatcher@36cf83c4[dispatcher = DefaultDispatcher]]
scratch.kts:89 2. called flowFoo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@73cd03d9, LimitingDispatcher@36cf83c4[dispatcher = DefaultDispatcher]], value: 100
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@73cd03d9, LimitingDispatcher@36cf83c4[dispatcher = DefaultDispatcher]], value: 200
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@73cd03d9, LimitingDispatcher@36cf83c4[dispatcher = DefaultDispatcher]], value: 300
scratch.kts:89 6. emitted flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 7. completed flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 ---------
scratch.kts:89 1. launched fooWithContext  @ [StandaloneCoroutine{Active}@4f8e5cde, BlockingEventLoop@22927a81]
scratch.kts:89 2. called flowFoo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@4f8e5cde, BlockingEventLoop@22927a81], value: 100
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@4f8e5cde, BlockingEventLoop@22927a81], value: 200
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@4f8e5cde, BlockingEventLoop@22927a81], value: 300
scratch.kts:89 6. emitted flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 7. completed flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 ---------
scratch.kts:89 1. launched fooWithFlowOn  @ [StandaloneCoroutine{Active}@5fcfe4b2, BlockingEventLoop@22927a81]
scratch.kts:89 2. called flowFoo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 6. emitted flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 7. completed flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@5fcfe4b2, BlockingEventLoop@22927a81], value: 100
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@5fcfe4b2, BlockingEventLoop@22927a81], value: 200
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@5fcfe4b2, BlockingEventLoop@22927a81], value: 300
scratch.kts:89 ---------
scratch.kts:89 1. launched fooWithFlowOnOuter  @ [StandaloneCoroutine{Active}@782830e, BlockingEventLoop@22927a81]
scratch.kts:89 2. called flowFoo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 6. emitted flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 7. completed flow foo @ [BlockingCoroutine{Active}@3581c5f3, BlockingEventLoop@22927a81]
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@782830e, BlockingEventLoop@22927a81], value: 100
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@782830e, BlockingEventLoop@22927a81], value: 200
scratch.kts:89 3-5. collected flowFoo @ [StandaloneCoroutine{Active}@782830e, BlockingEventLoop@22927a81], value: 300
scratch.kts:89 ---------