junit - Robolectric 4.4 单元测试错误 - 主循环器已将未执行的可运行文件排队

Question

与此有关的单元测试错误

Called loadFromPath(/system/framework/framework-res.apk, true); mode=binary sdk=28
java.lang.Exception: Main looper has queued unexecuted runnables. 
This might be the cause of the test failure. You might need a shadowOf(getMainLooper()).idle() call.

我们正在使用 Robolectric 4.4 编译到目标 29，但确保在运行单元测试时我们的目标是 28，因为 JDK 仍然是 8 而不是 9。这是一段代码，但我似乎无法在任何地方为 loopers 添加 idle()让这开心

@RunWith(AndroidJUnit4::class)
@LooperMode(LooperMode.Mode.PAUSED)
class MyRoomActivityTest {

    @get:Rule
    val activityRule = ActivityTestRule(MyRoomActivity::class.java, true, false)

    @Inject lateinit var mockViewModel: NewMyRoomActivityViewModel

    @Inject lateinit var locationManager: LocationManager

    private var testViewStateLiveData: MutableLiveData<NewMyRoomActivityViewModel.MyRoomActivityViewState> = MutableLiveData()

    @Before
    fun setUp() {
        RobolectricTestGEComponent.GraphHolder.testGraph.inject(this)
        whenever(mockViewModel.viewState).thenReturn(testViewStateLiveData)
        shadowOf(getMainLooper()).idle() // doesn't work here
    }

    @Test
    fun `launch activity sets ViewModel room Id`() {
        val roomId = "TestMyRoomId"
        shadowOf(getMainLooper()).idle() // doesn't work here either 
        activityRule.launchActivity(MyRoomActivity.newIntent(ApplicationProvider.getApplicationContext(), roomId))  // fails here all the time
        verify(mockViewModel).initialize(roomId)
    }
.....
}