Spek with Subjects - Spec

RoundDistancesPresenterSpec.kt

@RunWith(JUnitPlatform::class)
class DistancesPresenterSpec : Spek({

    rxGroup("DistancePresenter") {

        val view: DistancesPresenter.View = mock()
        val roundInteractor: RoundInteractor = mock()
        val tested = DistancesPresenter(roundInteractor)

        var holeSubject: PublishSubject<Hole> = PublishSubject.create()
        var distancesSubject: PublishSubject<List<MetricRoundDistances>> = PublishSubject.create()
        var distanceUnitSubject: PublishSubject<DistanceUnit> = PublishSubject.create()

        val distances = listOf(
                MetricRoundDistances(150, 125, 100),
                MetricRoundDistances(250, 240, 230))

        val hole1 = Hole().apply { sequence = 1 }
        val hole2 = Hole().apply { sequence = 2 }

        beforeEachTest {
            reset(view)
            reset(roundInteractor)

            holeSubject = PublishSubject.create()
            distancesSubject = PublishSubject.create()
            distanceUnitSubject = PublishSubject.create()

            whenever(roundInteractor.changeHoleEvents()).thenReturn(holeSubject)
            whenever(roundInteractor.distancesEvents()).thenReturn(distancesSubject)
            whenever(roundInteractor.distanceUnitEvents()).thenReturn(distanceUnitSubject)

            tested.attachView(view)
        }

        afterEachTest {
            tested.stop()
        }

        given("distances in meters for hole 1") {
            beforeEachTest {
                tested.start()

                holeSubject.onNext(hole1)
                distancesSubject.onNext(distances)
                distanceUnitSubject.onNext(DistanceUnit.METRIC)
            }

            it("should display distances for hole 1") {
                verify(view).displayDistancesToGreen("150", "125", "100")
            }

            it("should display distance units in meters") {
                verify(view).displayDistanceUnit(true)
            }

            on("change to hole 2") {
                holeSubject.onNext(hole2)

                it("should display distances for hole 2") {
                    verify(view).displayDistancesToGreen("250", "240", "230")
                }
            }

            on("distances update") {
                val distancesUpdate = listOf(
                        MetricRoundDistances(30, 10, 4),
                        MetricRoundDistances(350, 325, 300))

                distancesSubject.onNext(distancesUpdate)

                it("should display updated distances for hole 1") {
                    verify(view).displayDistancesToGreen("30", "10", "4")
                }
            }

            on("change to imperial system") {
                distanceUnitSubject.onNext(DistanceUnit.IMPERIAL)

                it("should display distances in yards for hole 1") {
                    verify(view).displayDistancesToGreen("164", "137", "109")
                }

                it("should display distance units in yards") {
                    verify(view).displayDistanceUnit(false)
                }
            }

            on("wrong distance update") {
                distancesSubject.onError(Throwable())

                it("should display error") {
                    verify(view).displayError()
                }
            }
        }
    }
})