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[SOLVED?] `sample-mvi` crashes on Start

See original GitHub issue

When i start it on Android Studio 3.1.2, app crashes with stack like this:

05-28 10:23:15.357 28499-28499/com.hannesdorfmann.mosby3.sample.mvi E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.hannesdorfmann.mosby3.sample.mvi, PID: 28499
    java.lang.IllegalStateException: Fatal Exception thrown on Scheduler.
        at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:111)
        at android.os.Handler.handleCallback(Handler.java:751)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6119)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
     Caused by: java.lang.IllegalStateException: ViewState observable must not reach error state - onError()
        at com.hannesdorfmann.mosby3.mvi.DisposableViewStateObserver.onError(DisposableViewStateObserver.java:22)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.checkTerminated(ObservableObserveOn.java:276)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.java:172)
        at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:252)
        at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:109)
        at android.os.Handler.handleCallback(Handler.java:751) 
        at android.os.Handler.dispatchMessage(Handler.java:95) 
        at android.os.Looper.loop(Looper.java:154) 
        at android.app.ActivityThread.main(ActivityThread.java:6119) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
     Caused by: java.lang.IllegalStateException: Only a single observer allowed.
        at io.reactivex.subjects.UnicastSubject.subscribeActual(UnicastSubject.java:150)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.subscribeInner(ObservableFlatMap.java:162)
        at io.reactivex.internal.operators.observable.ObservableFlatMap$MergeObserver.onNext(ObservableFlatMap.java:139)
        at io.reactivex.internal.operators.observable.ObservableFromArray$FromArrayDisposable.run(ObservableFromArray.java:107)
        at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:36)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableFlatMap.subscribeActual(ObservableFlatMap.java:55)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableDoOnEach.subscribeActual(ObservableDoOnEach.java:42)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableConcatMap$ConcatMapDelayErrorObserver.drain(ObservableConcatMap.java:467)
        at io.reactivex.internal.operators.observable.ObservableConcatMap$ConcatMapDelayErrorObserver.onSubscribe(ObservableConcatMap.java:325)
        at io.reactivex.internal.operators.observable.ObservableFromArray.subscribeActual(ObservableFromArray.java:30)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableConcatMap.subscribeActual(ObservableConcatMap.java:54)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableCombineLatest$LatestCoordinator.subscribe(ObservableCombineLatest.java:119)
        at io.reactivex.internal.operators.observable.ObservableCombineLatest.subscribeActual(ObservableCombineLatest.java:73)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.internal.operators.observable.ObservableObserveOn.subscribeActual(ObservableObserveOn.java:45)
        at io.reactivex.Observable.subscribe(Observable.java:10700)
        at io.reactivex.Observable.subscribeWith(Observable.java:10751)
        at com.hannesdorfmann.mosby3.mvi.MviBasePresenter.subscribeViewState(MviBasePresenter.java:366)
        at com.hannesdorfmann.mosby3.sample.mvi.view.shoppingcartoverview.ShoppingCartOverviewPresenter.bindIntents(ShoppingCartOverviewPresenter.java:108)
        at com.hannesdorfmann.mosby3.mvi.MviBasePresenter.attachView(MviBasePresenter.java:248)
        at com.hannesdorfmann.mosby3.FragmentMviDelegateImpl.onStart(FragmentMviDelegateImpl.java:161)
        at com.hannesdorfmann.mosby3.mvi.MviFragment.onStart(MviFragment.java:91)
        at android.support.v4.app.Fragment.performStart(Fragment.java:2287)
        at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1458)
        at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1750)
        at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1819)
        at android.support.v4.app.FragmentManagerImpl.dispatchStateChange(FragmentManager.java:3227)
        at android.support.v4.app.FragmentManagerImpl.dispatchStart(FragmentManager.java:3186)
        at android.support.v4.app.FragmentController.dispatchStart(FragmentController.java:203)
        at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:582)
        at android.support.v7.app.AppCompatActivity.onStart(AppCompatActivity.java:177)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1248)
        at android.app.Activity.performStart(Activity.java:6696)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2628)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
        at android.app.ActivityThread.-wrap12(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        	... 5 more