Question

编辑：供将来的读者使用。我不知道这个问题是否会对您有很大帮助。有趣的逻辑已经发生了很大变化，因此我将关闭该问题，但不会删除。

我正在尝试为ViewModel编写一些单元测试。我正在使用Mockk和Junit5。

会发生什么：伪造的存储库返回fakeresponse，我称之为VM中的乐趣，它将实时数据设置为伪响应数据。

实际发生的事情：

Exception in thread "DefaultDispatcher-worker-2 @coroutine#1" io.mockk.MockKException: no answer found for: DrillRepository(#1).loadDrillTypes()
    at io.mockk.impl.stub.MockKStub.defaultAnswer(MockKStub.kt:90)
    at io.mockk.impl.stub.MockKStub.answer(MockKStub.kt:42)
    at io.mockk.impl.recording.states.AnsweringState.call(AnsweringState.kt:16)
    at io.mockk.impl.recording.CommonCallRecorder.call(CommonCallRecorder.kt:53)
    at io.mockk.impl.stub.MockKStub.handleInvocation(MockKStub.kt:263)
    at io.mockk.impl.instantiation.JvmMockFactoryHelper$mockHandler$1.invocation(JvmMockFactoryHelper.kt:25)
    at io.mockk.proxy.jvm.advice.Interceptor.call(Interceptor.kt:20)
    at com.nikolam.basketpro.data.DrillRepository.loadDrillTypes(DrillRepository.kt:11)
    at com.nikolam.basketpro.ui.drills.selection.DrillsSelectionViewModel$fetchDrillTypes$1.invokeSuspend(DrillsSelectionViewModel.kt:41)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(Dispatched.kt:241)
    at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:594)
    at kotlinx.coroutines.scheduling.CoroutineScheduler.access$runSafely(CoroutineScheduler.kt:60)
    at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:740)

org.opentest4j.AssertionFailedError: 
Expected :[DrillsType(drillType_title=title1, drillType_imageUrl=url1), DrillsType(drillType_title=title2, drillType_imageUrl=url2)]
Actual   :null
<Click to see difference>


    at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)
    at org.junit.jupiter.api.AssertionUtils.failNotEqual(AssertionUtils.java:62)
    at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:182)
    at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:177)
    at org.junit.jupiter.api.Assertions.assertEquals(Assertions.java:1124)
    at com.nikolam.basketpro.ui.drills.selection.DrillsSelectionViewModelTest.drillTypeListWillBePopulatedOnSuccess(DrillsSelectionViewModelTest.kt:43)
    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.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:686)
    at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
    at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
    at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:140)
    at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:84)
    at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
    at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
    at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:205)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:201)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:137)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:71)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at java.util.ArrayList.forEach(ArrayList.java:1257)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at java.util.ArrayList.forEach(ArrayList.java:1257)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:248)
    at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$5(DefaultLauncher.java:211)
    at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:226)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:199)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:132)
    at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
    at com.intellij.rt.execution.junit.IdeaTestRunner$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)

这是测试

@ExtendWith(value = [InstantExecutorExtension::class, TestSchedulerExtension::class])
internal class DrillsSelectionViewModelTest{

    val mockkDrillRepository = mockk<DrillRepository>()

    lateinit var drillsSelectionViewModel : DrillsSelectionViewModel

    @BeforeEach
    fun setup(){

        drillsSelectionViewModel = DrillsSelectionViewModel(mockkDrillRepository)

        val fakeResponse = Observable.just(DrillsType("title1", "url1"), DrillsType("title2","url2"))


        every{ mockkDrillRepository.loadDrillTypes()} returns fakeResponse

    }

    @Test
    fun `should update the livedata with correct data from the repository`(){

        drillsSelectionViewModel.fetchDrillTypes()

        assertEquals(arrayListOf(DrillsType("title1", "url1"), DrillsType("title2","url2")), getValue(drillsSelectionViewModel.drillsTypeList.value))

    }

}

这是测试中扩展的两个类

class InstantExecutorExtension : BeforeEachCallback, AfterEachCallback {

    override fun beforeEach(context: ExtensionContext?) {
        ArchTaskExecutor.getInstance().setDelegate(object : TaskExecutor() {
            override fun executeOnDiskIO(runnable: Runnable) {
                runnable.run()
            }

            override fun postToMainThread(runnable: Runnable) {
                runnable.run()
            }

            override fun isMainThread(): Boolean {
                return true
            }
        })
    }

    override fun afterEach(context: ExtensionContext?) {
        ArchTaskExecutor.getInstance().setDelegate(null)
    }

}

class TestSchedulerExtension : BeforeTestExecutionCallback, AfterTestExecutionCallback {

    override fun beforeTestExecution(context: ExtensionContext?) {
        RxJavaPlugins.setIoSchedulerHandler { Schedulers.trampoline() }
        RxJavaPlugins.setComputationSchedulerHandler { Schedulers.trampoline() }
        RxJavaPlugins.setNewThreadSchedulerHandler { Schedulers.trampoline() }
        RxAndroidPlugins.setMainThreadSchedulerHandler { Schedulers.trampoline() }
    }

    override fun afterTestExecution(context: ExtensionContext?) {
        RxJavaPlugins.reset()
        RxAndroidPlugins.reset()
    }

}

这是SUT

class DrillsSelectionViewModel(private val repository: DrillRepository): ViewModel() {

    private val compositeDisposable = CompositeDisposable()

    private var _drillsTypeList = MutableLiveData<ArrayList<DrillsType>>()
    val drillsTypeList: LiveData<ArrayList<DrillsType>>
        get() = _drillsTypeList


    init{

        fetchDrillTypes()
    }

    fun fetchDrillTypes()
    {

        val list = ArrayList<DrillsType>()

        viewModelScope.launch(Dispatchers.IO) {
            compositeDisposable += repository.loadDrillTypes()
                .subscribeWith(object : DisposableObserver<DrillsType>() {

                    override fun onError(e: Throwable) {
                        Log.d("TAG", e?.message)
                    }

                    override fun onNext(data: DrillsType) {
                        Log.d("TAG", "data is " + data.toString())
                        list.add(data)
                    }

                    override fun onComplete() {
                        Log.d("TAG", "COMPLETE")
                        _drillsTypeList.postValue(list)
                    }
                })
        }
    }


    override fun onCleared() {
        super.onCleared()
        if (!compositeDisposable.isDisposed) {
            compositeDisposable.dispose()
        }
    }

}

DOC



    fun loadDrillTypes(): Observable<DrillsType> {
        return remoteDataSource.loadDrillTypes()
    }


    fun loadDrillList(drillType : String): Observable<Drill> {
        return remoteDataSource.loadDrillList(drillType)
    }
}

我尝试过的：

从混合物中去除协程。我以为删除“ viewmodelscope.launch”将使测试工作正常，因为我认为它与协程有关，协程未完成，未及时执行或未侦听适当的线程。
尝试使用下面发布的2个扩展类（以替换JUnit4中的即时执行规则）
在Google上进行了大量的搜索以查找类似的问题...

很长的帖子，很抱歉，您需要随时询问任何更多信息或代码。如果可能，还指出一些可以做得更好的错误/事情。任何带有解释的答案都非常感谢。我真的很想了解潜在的问题。非常感谢你！

编辑：我正在考虑可能是由于RXKotlin

Answer 1

在您的setup()方法中，您首先要创建一个视图模型，然后在存储库中配置模拟响应。但是，您的viewmodel试图在实例化时立即从存储库中获取该响应（在fetchDrillTypes()块中调用的init中），因此它发生在模拟就绪之前。您只需要对setup()中的呼叫重新排序，以使drillsSelectionViewModel = ...最后发生。

Android Kotlin单元测试因io.mockk.MockKException失败：未找到答案

1 个答案: