how would i write a unit test for that? because as...

# coroutines

[bitkid]

how would i write a unit test for that? because as soon as i run this in runBlocking{} in the test doSomething() will be called on the same thread.

[elizarov]

It will not be called in the same thread in test. By default, async { ... } uses CommonPool dispatcher and doSomething will be executed in that another thread.

[christophsturm]

but we actually want it running in the same thread. can i tell async that it should use the same thread?

[christophsturm]

it will still be async because the method that we call is a non blocking suspend method

[elizarov]

You can specify the context for async explicitly if you need it.

[elizarov]

async(ctx) { ... }

[christophsturm]

ok so just use unconfined to run it in the same thread?

[elizarov]

Unconfined runs in the same thread only until the first suspension point.

[elizarov]

If you actually want the same thread, then from inside runBlocking you should be passing coroutineContext.

[christophsturm]

runBlocking is just what we use in the test suite

[elizarov]

So, if you want it to run in `UI' thread in production, then you use async(UI) { … } and for tests you make UI injectable and use coroutineContext that’s available inside runBlocking