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kotlinlang

Why does this test fail? ```
			val progress = Channel&lt;Long&gt;(Channel.CONFLATED)
			val progressList = GlobalScope.async { progress.toList() }

			runBlocking {
				val progressResult = (0L..20L step 2).onEach { progress.offer(it) }
				progress.close()

				assertThat(progressResult.toList()).toBe(progressList.await())
			}
```
`progressList` is []...

not enough time to dispatch those updates.
You use offer which doesn’t suspend

send also doesn't work :face_with_head_bandage:

I see that when I put a `delay(20)` the test passes with send...

I just don't understand why, `send` should have suspended like you said?

Because this is how conflaited channel works

Thanks, that's much clearer! So in a real download, it would work since there is some time while reporting download progress, or will `toList()` return immediately while progress is still being sent..? I don't necessarily suspend while receiving bytes...

If progress is so fast and channel even never dispatched why it's so important to have all events

Use non-conflated channels if you want to have all events and warranty of delivery

It's not that fast, I'm just unit testing, so I have a mock server... I just wanted to make sure that I'm getting *some* progress, I just didn't get *any*...

You run it in runBlocking and do not give dispatcher chance to dispatch any other coroutine between offer calls

Try to add yeld after each progress call, it at least allow to run any other coroutines, so may be solve your problem with unit test

yield still doesn't work... only delay(1) or Thread.sleep(20), Thread.sleep(10) sometimes works, sometimes doesn't :upside_down_face:

I need at least the last part to be able to sum up the total bytes downloaded... but you're saying that in that case I'll be getting it since it's not going to go so fast...

But the async is running on GlobalScope, which is Default dispatcher... so why shouldn't it run (even in runBlocking... GlobalScope doesn't inherit from it...)?

If you want overall amount of bytes, just return it as result of suspend function

Do not use conflate channel to deliver critical result

Yes, you right about global scope didn't notice that