Android 类的协同程序单元测试失败

在单元测试协同过程中，我面临一个奇怪的问题。这个类上有两个测试，当分别运行时，它们都通过了，当我运行完整的测试类时，一个失败，并出现断言错误。 我正在使用

MainCoroutineRule

来使用

TestCoroutineScope

并依赖于最新的Coroutine测试库 以下是测试：

    @Test
    fun testHomeIsLoadedWithShowsAndFavorites() {
        runBlocking {
            // Stubbing network and repository calls
            whenever(tvMazeApi.getCurrentSchedule("US", currentDate))
                .thenReturn(getFakeEpisodeList())
            whenever(favoriteShowsRepository.allFavoriteShowIds())
                .thenReturn(arrayListOf(1, 2))
        }

        mainCoroutineRule.runBlockingTest {
            // call home viewmodel
            homeViewModel.onScreenCreated()
            // Check if loader is shown
            assertThat(LiveDataTestUtil.getValue(homeViewModel.getHomeViewState())).isEqualTo(Loading)
            // Observe on home view state live data
            val homeViewState = LiveDataTestUtil.getValue(homeViewModel.getHomeViewState())
            // Check for success data
            assertThat(homeViewState is Success).isTrue()
            val homeViewData = (homeViewState as Success).homeViewData
            assertThat(homeViewData.episodes).isNotEmpty()
            // compare the response with fake list
            assertThat(homeViewData.episodes).hasSize(getFakeEpisodeList().size)
            // compare the data and also order
            assertThat(homeViewData.episodes).containsExactlyElementsIn(getFakeEpisodeViewDataList(true)).inOrder()
        }
    }

另一个测试几乎类似于测试没有收藏夹的节目。我正在尝试测试

HomeViewModel

方法，如下所示：

        homeViewStateLiveData.value = Loading
        val coroutineExceptionHandler = CoroutineExceptionHandler { _, exception ->
            onError(exception)
        }

        viewModelScope.launch(coroutineExceptionHandler) {
            // Get shows from network and favorites from room db on background thread
            val favoriteShowsWithFavorites = withContext(Dispatchers.IO) {
                val favoriteShowIds = favoriteShowsRepository.allFavoriteShowIds()
                val episodes = tvMazeApi.getCurrentSchedule(COUNTRY_US, currentDate)
                getShowsWithFavorites(episodes, favoriteShowIds)
            }
            // Return the combined result on main thread
            withContext(Dispatchers.Main) {
                onSuccess(favoriteShowsWithFavorites)
            }
        }
    }

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我找不到为什么单独运行的测试通过，而当测试整个类时，其中一个测试失败的实际原因。如果我遗漏了一些东西，请提供帮助。

Coroutine支持提供的改装和空间所有者暂停功能，并自行将其从UI线程中移出。因此，它们大大减少了开发人员处理线程回调的麻烦。最初，我通过

Dispatchers.IO

明确地将网络和数据库的挂起调用移动到IO。这是不必要的，也会导致不必要的上下文切换，从而导致测试失败。由于库会自动执行此操作，所以只需在UI上处理可用的数据即可

        viewModelScope.launch(coroutineExceptionHandler) {
            // Get favorite shows from db, suspend function in room will launch a new coroutine with IO dispatcher
            val favoriteShowIds = favoriteShowsRepository.allFavoriteShowIds()
            // Get shows from network, suspend function in retrofit will launch a new coroutine with IO dispatcher
            val episodes = tvMazeApi.getCurrentSchedule(COUNTRY_US, currentDate)

            // Return the result on main thread via Dispatchers.Main
            homeViewStateLiveData.value = Success(HomeViewData(getShowsWithFavorites(episodes, favoriteShowIds)))
        }

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协同程序支持附带的改进和空间拥有者暂停功能，并自行将它们从UI线程中移出。因此，它们大大减少了开发人员处理线程回调的麻烦。最初，我通过

Dispatchers.IO

明确地将网络和数据库的挂起调用移动到IO。这是不必要的，也会导致不必要的上下文切换，从而导致测试失败。由于库会自动执行此操作，所以只需在UI上处理可用的数据即可

        viewModelScope.launch(coroutineExceptionHandler) {
            // Get favorite shows from db, suspend function in room will launch a new coroutine with IO dispatcher
            val favoriteShowIds = favoriteShowsRepository.allFavoriteShowIds()
            // Get shows from network, suspend function in retrofit will launch a new coroutine with IO dispatcher
            val episodes = tvMazeApi.getCurrentSchedule(COUNTRY_US, currentDate)

            // Return the result on main thread via Dispatchers.Main
            homeViewStateLiveData.value = Success(HomeViewData(getShowsWithFavorites(episodes, favoriteShowIds)))
        }

---

你能链接说明上下文切换是在这些库内部完成的文档吗？你能链接一下说明上下文切换是在这些库内部完成的文档吗？非常感谢。