Hey all I m trying to unit test using Robolectric and am run kotlinlang #rx

Maybe.just(list)
    .flatMapSingle { repository.getStuffList(id) }
    .map { stuffList -> stuffList.filter { stuff -> list.contains(stuff) } }
    .flatMapCompletable { stuffAfterFilter ->
         secondRepository.doThing(stuffAfterFilter)
              .doOnError { Completable.error(IllegalStateException("failure")) }
              .andThen { repository.deleteStuff(stuffAfterFilter) }
     }
     .andThen(repository.getStuffList(id))

What’s the best way to have each call to

repository.getStuffList(id)

return different items when they’re called? Right now I’ve got order of operations setup in my test (which has worked in the past), but now the first time the method is called it’s returning

stuffList2

instead of

stuffList1

whenever(repository.getStuffList("id")).thenReturn(Single.just(stuffList1))
whenever(secondRepository.doThing(any())).thenReturn(Completable.complete())
whenever(repository.deleteStuff(any())).thenReturn(Completable.complete())
whenever(repository.getStuffList("id")).thenReturn(Single.just(stuffList2))

Am I on the right path here?

Paul Woitaschek

12/28/2019, 9:53 AM

Use fromCallable and handle your logic there. You should treat rx as encapsulated function and don't rely on subscription happening immediately

Ariana

12/30/2019, 4:27 PM

Ah, I’ve never heard of that before. You’re saying use

fromCallable

in the test?

Paul Woitaschek

12/30/2019, 4:30 PM

Yes that way you can keep track of the subscriptions

val stuffList1 = listOf(1,2,3)
    val stuffList2 = listOf(4,5,6)
    var invocation = 0
    Single.fromCallable {
        when(++invocation){
            1 -> stuffList1
            2 -> stuffList2
            else -> error("Didn't answer invocation $invocation")
        }
    }

Ariana

12/30/2019, 4:31 PM

Oh that’s amazing. Thank you!

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