TrendingViewModelTest
@RunWith(JUnit4::class)
class TrendingViewModelTest {
private lateinit var trendingRepository: TrendingRepository
private lateinit var trendingViewModel: TrendingViewModel
@get:Rule
val schedulers = RxImmediateSchedulerRule()
@Before
fun setUp() {
trendingRepository = mock(TrendingRepository::class.java)
trendingViewModel = TrendingViewModel(trendingRepository)
}
@Test
fun testWithNetwork() {
trendingViewModel.isConnected = true
trendingViewModel.fetchTrendingRepos()
verify(trendingRepository, times(1)).getTrendingRepos()
}
//...
}
趋势视图模型
fun fetchTrendingRepos() {
if (isConnected) {
loadingProgress.value = true
compositeDisposable.add(
trendingRepository.getTrendingRepos().subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe({ response ->
run {
loadingProgress.value = false
},
{ error ->
loadingProgress.value = false
}
)
)
}
RxImmediateSchedulerRule：
class RxImmediateSchedulerRule : TestRule {
override fun apply(base: Statement?, description: Description?): Statement {
return object : Statement() {
@Throws(Throwable::class)
override fun evaluate() {
RxJavaPlugins.setIoSchedulerHandler { Schedulers.trampoline() }
RxJavaPlugins.setComputationSchedulerHandler { Schedulers.trampoline() }
RxJavaPlugins.setNewThreadSchedulerHandler { Schedulers.trampoline() }
RxAndroidPlugins.setInitMainThreadSchedulerHandler { Schedulers.trampoline() }
try {
base?.evaluate()
} finally {
RxJavaPlugins.reset()
RxAndroidPlugins.reset()
}
}
}
}
}
TrendingRepositoryImpl：
class TrendingRepositoryImpl @Inject constructor(
val apiService: GitHubApi,
val trendingDao: AppDao
) : TrendingRepository {
override fun getTrendingRepos(): Single<List<TrendingRepo>> {
return apiService.getTrendingGits()
}
}
趋势存储库：
interface TrendingRepository {
fun getTrendingRepos(): Single<List<TrendingRepo>>
}
在启动 Rxjava 调用fetchTrendingRepos()内部，它还会连接到"AndroidSchedulers.mainThread(("，这可能是导致它的原因。
java.lang.RuntimeException： Method getMainLooper in android.os.Looper not mocked. at android.os.Looper.getMainLooper(Looper.java( at androidx.arch.core.executor.DefaultTaskExecutor.isMainThread(DefaultTaskExecutor.java：77( at androidx.arch.core.executor.ArchTaskExecutor.isMainThread(ArchTaskExecutor.java：116( at androidx.lifecycle.LiveData.assertMainThread(LiveData.java：461( at androidx.lifecycle.LiveData.setValue(LiveData.java：304( at androidx.lifecycle.MutableLiveData.setValue(MutableLiveData.java：50( at com.manoj.trendgitz.mvvm.ui.TrendingViewModel.fetchTrendingRepos(TrendingViewModel.kt：32( at com.manoj.trendgitz.TrendingViewModelTest.testWithNetwork(TrendingViewModelTest.kt：52( 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.statement.InvokeMethod.evaluate(InvokeMethod.java：17( at org.junit.internal.runners.statement.RunBefores.evaluate(RunBefores.java：26( 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(
更新LiveData值时，还应添加@get:Rule var rule: TestRule = InstantTaskExecutorRule()。
不要忘记将以下内容添加到build.gradle文件中：
dependencies {
// ...
testImplementation "androidx.arch.core:core-testing:2.1.0"
}
此外，请相应地更改测试代码以避免NullPointerException：
@Test
fun testWithNetwork() {
trendingViewModel.isConnected = true
Mockito.`when`(trendingRepository.fetchTrendingRepos()).thenReturn(Single.just(listOf<TrendingRepo>()))
trendingViewModel.fetchTrendingRepos()
verify(trendingRepository, times(1)).getTrendingRepos()
}
Mockito.when()允许您在每次调用模拟方法时执行不同的操作。如果不使用它，您可能会看到可能的NullPointerException，具体取决于您的测试功能。
在应用的 build.gradle 中，在 android {} 下添加以下行
testOptions {
// Used for Unit testing Android dependent elements in /test folder
unitTests.includeAndroidResources = true
unitTests.returnDefaultValues = true
}
首先为core-testing添加testImplementation。
testImplementation 'androidx.arch.core:core-testing:2.1.0'
然后在单元测试类中添加变量rule的InstantTaskExecutorRule。
import androidx.arch.core.executor.testing.InstantTaskExecutorRule
class TrendingViewModelTest {
@get:Rule
val rule = InstantTaskExecutorRule()
}
如果您看到此错误而没有添加RxImmediateSchedulerRule。尝试将此规则添加到测试类中：
@Rule @JvmField
val instantTaskExecutorRule = InstantTaskExecutorRule()