Does anyone know why 1 out of 3 listeners gets emi...

# rx

[Grant Park]

Does anyone know why 1 out of 3 listeners gets emissions in backwards order given this sample demo of BehaviorSubject?
All three listeners should receive A and B but the third listener gets B and A and this unit test ultimately fails.

@Test
    fun `rxjava test`() {
        val eventHistory1 = ArrayList<String>()
        val eventHistory2 = ArrayList<String>()
        val eventHistory3 = ArrayList<String>()

        val behaviorSubject = BehaviorSubject.create<String>()

        behaviorSubject.subscribe {
            eventHistory1.add(it)
        }

        behaviorSubject.subscribe {
            eventHistory2.add(it)
            if (it == "A") behaviorSubject.onNext("B")
        }

        behaviorSubject.subscribe {
            eventHistory3.add(it)
        }

        behaviorSubject.onNext("A")

        println(eventHistory1)
        println(eventHistory2)
        println(eventHistory3)

        assert(eventHistory1 == eventHistory2)
        assert(eventHistory2 == eventHistory3)
    }