A modern programming language that makes developers happier.

kotlinlang

Would you please help me with the following?
I want to test that the buffer size of my `MutableSharedFlow&lt;T&gt;(replay = 0, extraBufferCapacity = 1, onBufferOverflow = BufferOverflow.DROP_OLDEST)` equals `1` (in reality it's variable). I can't figure out how to get this working in a unit test: every time I emit something it is immediately collected (I use Turbine to `test` the flow). I basically want to emit 2 items and verify that only the last one is collected, the oldest is dropped.

Maybe it's related to the unconfined dispatcher used by Turbine: I cannot pause that dispatcher, because it's not my test dispatcher?

This works:
```    @Test
    fun test() = testCoroutineDispatcher.runBlockingTest {
        val flow = MutableSharedFlow&lt;Int&gt;(
            replay = 0,
            extraBufferCapacity = 1,
            BufferOverflow.DROP_OLDEST
        )

        val emissions = mutableListOf&lt;Int&gt;()

        val subscription = flow.onEach { emissions += it }.launchIn(this)

        pauseDispatcher()
        flow.tryEmit(1)
        flow.tryEmit(2)
        resumeDispatcher()

        assertEquals(2, emissions.single())

        subscription.cancel()
    }```

But it's not very pretty, because it's somewhat imperative

Using Turbine I'd like to do:
```    @Test
    fun test() = testCoroutineDispatcher.runBlockingTest {
        val flow = MutableSharedFlow&lt;Int&gt;(
            replay = 0,
            extraBufferCapacity = 1,
            BufferOverflow.DROP_OLDEST
        )

        flow.test {
            pauseDispatcher()
            flow.tryEmit(1)
            flow.tryEmit(2)
            resumeDispatcher()

            assertEquals(2, expectItem())
            expectNoEvents()
        }
    }```
but that fails with:

```java.lang.AssertionError: 
Expected :2
Actual   :1```

Likely because of what I said: Turbine collects on the unconfined dispatcher, not my test coroutine dispatcher