Hello. I have a flow created with `channelFlow`, and a simple flow created with `flowOf`. I want to ...

# coroutines

[ylemoigne]

Hello. I have a flow created with channelFlow, and a simple flow created with flowOf. I want to concatenate them so I do val concatened = chanFlow.onCompletion { if(it==null) emitAll(simpleFlow) }. Then the flow is "launched" GlobalScope.launch { concatened.collect { ... } }. When I cancel the resulting job, the chanFlow stop correctly and throw CancellationException, but the second flow values are still collected. The throwable in onCompletion is null. What is the correct way to handle this ?

[Paul Woitaschek]

Can you post a self contained example?

[ylemoigne]

Yes

Untitled

[Vsevolod Tolstopyatov [JB]]

It’s because cancellation is not an upstream exception (it’s also mentioned in onCompletion documentation).
You can use if (it == null && coroutineContext.isActive) to ignore cancellation as well

[ylemoigne]

Ok, thanks you. (I saw the line in the doc about cancellation exception, but did not see how to achieve what I wanted and if I was on the right track).