Problem in creating unit test android with RxJava and Mockito

The test comes down to making the assertions that the methods are called when the execution is done successfully, but an error is occurring that I can not resolve.

My class:

class LoginActivityPresenter(private var authUseCase: AuthStructure, private var view: LoginActivityView, private var database: SupervisorDatabaseInterface) {

        fun tryLogin(identifier: String, password: String) {
            val disposable = database.getQrCode()
                    .doOnSubscribe { view.showProgressDialog() }
                    .doAfterTerminate { view.hideProgressDialog() }
                    .flatMap { it -> authUseCase.authenticate(identifier, password, it.qrcode) }
                    .subscribe(
                            {
                                database.insertUserToken(it)
                                view.loginSucess()
                            },
                            {
                                when (it) {
                                    is EmptyResultSetException -> {
                                        view.loginErrorNoQrCode()
                                    }
                                    else -> {
                                        view.loginError()
                                        it.printStackTrace()
                                    }
                                }
                            }
                    )
        }
    }

Test class:

class LoginActivityPresenterTest {
    private val immediateScheduler = object : Scheduler() {
        override fun createWorker(): Worker {
            return ExecutorScheduler.ExecutorWorker(Executor { it.run() })
        }
    }

    private fun <T> any(): T {
        Mockito.any<T>()
        return uninitialized()
    }

    private fun <T> uninitialized(): T = null as T

    @Mock
    private lateinit var mLoginActivityView: LoginActivityView

    @Spy
    private lateinit var mAuthStructure: AuthStructure

    @Mock
    private lateinit var mSupervisorDatabaseInterface: SupervisorDatabaseInterface

    @InjectMocks
    private lateinit var mLoginActivityPresenter: LoginActivityPresenter

    @Before
    fun setup() {
        MockitoAnnotations.initMocks(this)

        RxJavaPlugins.setInitIoSchedulerHandler { immediateScheduler }
        RxAndroidPlugins.setInitMainThreadSchedulerHandler { immediateScheduler }
    }

    @After
    fun tearDown() {
        RxJavaPlugins.reset()
        RxAndroidPlugins.reset()
    }

    @Test
    fun 'should happen when you successfully log in'() {
        val userToken = UserToken()
        val qrCode = QRCode("qr")
        val identifier = "test"
        val password = "password"

'when'(mSupervisorDatabaseInterface.getQrCode()).thenReturn(Single.just(qrCode))

        mLoginActivityPresenter.tryLogin(identifier, password)

        verify(mLoginActivityView, times(1)).showProgressDialog()

        verify(mLoginActivityView, times(1)).hideProgressDialog()

        verify(mLoginActivityView, times(1)).loginSucess()

        verify(mLoginActivityView, never()).loginError()
    }
}

The result:

java.lang.NullPointerException: The single returned by the mapper is null
    at io.reactivex.internal.functions.ObjectHelper.requireNonNull(ObjectHelper.java:39)
    at io.reactivex.internal.operators.single.SingleFlatMap$SingleFlatMapCallback.onSuccess(SingleFlatMap.java:76)
    at io.reactivex.internal.operators.single.SingleDoAfterTerminate$DoAfterTerminateObserver.onSuccess(SingleDoAfterTerminate.java:70)
    at io.reactivex.internal.operators.single.SingleDoOnSubscribe$DoOnSubscribeSingleObserver.onSuccess(SingleDoOnSubscribe.java:77)
    at io.reactivex.internal.operators.single.SingleJust.subscribeActual(SingleJust.java:30)
    at io.reactivex.Single.subscribe(Single.java:3096)
    at io.reactivex.internal.operators.single.SingleDoOnSubscribe.subscribeActual(SingleDoOnSubscribe.java:41)
    at io.reactivex.Single.subscribe(Single.java:3096)
    at io.reactivex.internal.operators.single.SingleDoAfterTerminate.subscribeActual(SingleDoAfterTerminate.java:43)
    at io.reactivex.Single.subscribe(Single.java:3096)
    at io.reactivex.internal.operators.single.SingleFlatMap.subscribeActual(SingleFlatMap.java:36)
    at io.reactivex.Single.subscribe(Single.java:3096)
    at io.reactivex.Single.subscribe(Single.java:3082)
    at id.teste.supervisor.presenters.login.LoginActivityPresenter.tryLogin(LoginActivityPresenter.kt:14)
    at id.teste.supervisor.presenters.login.LoginActivityPresenterTest.should happen when you successfully log in(LoginActivityPresenterTest.kt:72)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:131)


Wanted but not invoked:
mLoginActivityView.loginSucess();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenterTest.should happen when you successfully log in(LoginActivityPresenterTest.kt:78)

However, there were exactly 3 interactions with this mock:
mLoginActivityView.showProgressDialog();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$1.accept(LoginActivityPresenter.kt:11)

mLoginActivityView.loginError();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$5.accept(LoginActivityPresenter.kt:25)

mLoginActivityView.hideProgressDialog();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$2.run(LoginActivityPresenter.kt:12)


Wanted but not invoked:
mLoginActivityView.loginSucess();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenterTest.should happen when you successfully log in(LoginActivityPresenterTest.kt:78)

However, there were exactly 3 interactions with this mock:
mLoginActivityView.showProgressDialog();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$1.accept(LoginActivityPresenter.kt:11)

mLoginActivityView.loginError();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$5.accept(LoginActivityPresenter.kt:25)

mLoginActivityView.hideProgressDialog();
-> at id.teste.supervisor.presenters.login.LoginActivityPresenter$tryLogin$disposable$2.run(LoginActivityPresenter.kt:12)


    at id.teste.supervisor.presenters.login.LoginActivityPresenterTest.should happen when you successfully log in(LoginActivityPresenterTest.kt:78)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:131)


Process finished with exit code 255