UnitTest 中 MutableLiveData 的 setValue 和 postValue
setValue and postValue on MutableLiveData in UnitTest
我尝试在我的应用程序上测试一些方法，但在调用 mutablelivedata.postValue 时出现错误。这是一个片段和错误消息：
@Test
public void callStartScreenRepository(){
Observer<User> userObserver = mock(Observer.class);
startScreenViewModel.returnUser().observeForever(userObserver);
maennlich = new User();
maennlich.setVorname("Christian");
MutableLiveData<User> userTest = new MutableLiveData<>();
userTest.postValue(maennlich);
when(startScreenRepository.userWebService("testUser")).thenReturn(userTest);
verify(userObserver).onChanged(maennlich);
}
java.lang.RuntimeException：android.os.Looper 中的方法 getMainLooper 未被模拟。有关详细信息，请参阅 http://g.co/androidstudio/not-mocked。
at android.os.Looper.getMainLooper(Looper.java)
at android.arch.core.executor.DefaultTaskExecutor.postToMainThread(DefaultTaskExecutor.java:48)
at android.arch.core.executor.AppToolkitTaskExecutor.postToMainThread(AppToolkitTaskExecutor.java:100)
at android.arch.lifecycle.LiveData.postValue(LiveData.java:277)
at android.arch.lifecycle.MutableLiveData.postValue(MutableLiveData.java:28)
at com.example.cfrindt.foodtracking.ViewModels.StartScreenViewModelTest.callStartScreenRepository(StartScreenViewModelTest.java:102)
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.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.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.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access[=11=]0(ParentRunner.java:58)
at org.junit.runners.ParentRunner.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:117)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:42)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:262)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:84)
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.AppMain.main(AppMain.java:147)
无论我使用 setValue() 还是 postValue()，我都会收到此错误。
我怎样才能让它发挥作用？
首先，您需要使用 InstantTaskExecutorRule，这意味着：
@Rule public InstantTaskExecutorRule instantExecutorRule = new InstantTaskExecutorRule();
这将允许立即使用 MutableLiveData。请记住在您的应用的 build.gradle 中包含导入：
testCompile "android.arch.core:core-testing:$rootProject.ext.arch_version"
然后，您需要使用覆盖 RxSchedulers 的规则定义 JUnit 规则，或者在 @Before 中使用 RxAndroidPlugins 覆盖调度程序（如果您使用的是 RxJava）
RxSchedulersOverrideRule:
public class RxSchedulersOverrideRule implements TestRule {
@Override public Statement apply(final Statement base, Description description) {
return new Statement() {
@Override public void evaluate() throws Throwable {
RxAndroidPlugins.reset();
RxAndroidPlugins.setMainThreadSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.reset();
RxJavaPlugins.setIoSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.setComputationSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.setNewThreadSchedulerHandler(scheduler -> Schedulers.trampoline());
base.evaluate();
RxAndroidPlugins.reset();
RxJavaPlugins.reset();
}
};
}
}
并在测试中调用class:
@Rule public RxSchedulersOverrideRule rxSchedulersOverrideRule = new RxSchedulersOverrideRule();
另一个选项是在 @Before 的 setup() 中调用：
RxAndroidPlugins.setInitMainThreadSchedulerHandler(schedulerCallable -> Schedulers.trampoline());
使用后需要在@After's tearDownClass()中重新设置：
RxAndroidPlugins.reset();
@Carlos Daniel 的回答对我帮助很大，但面临另一个问题，即 Rule 未应用于 PowerMockRunner。对于那些有同样问题的人，这里是解决方案：
@RunWith(PowerMockRunner::class)
@PowerMockRunnerDelegate(MockitoJUnitRunner::class) //this line allows you to use the powermock runner and mockito runner
@PrepareForTest(UnderTestClass::class)
class UnderTestClassTest {
@get:Rule
var instantExecutorRule = InstantTaskExecutorRule()
确保观察者不在主线程上
Jeroen Mols outlines each implementation 适用于 JUnit 4 和 JUnit 5。我使用 Junit 5 方法使用 Kotlin、JUnit 5、MockK 和 AssertJ 库进行 Coinverse Open App 的本地单元测试。
JUnit 4
@Carlos Daniel 的 实现 InstantExecutorRule 对于 JUnit 4 是正确的。
ExampleUnitTest.kt
class ExampleUnitTest {
@get:Rule
val rule = InstantTaskExecutorRule()
@Test
fun `my test`() {
val mutableLiveData = MutableLiveData<String>()
mutableLiveData.postValue("test")
assertEquals("test", mutableLiveData.value)
}
}
build.gradle
dependencies {
testImplementation 'android.arch.core:core-testing:X.X.X'
}
JUnit 5
InstantExecutorExtension.kt
import androidx.arch.core.executor.ArchTaskExecutor
import androidx.arch.core.executor.TaskExecutor
import org.junit.jupiter.api.extension.AfterEachCallback
import org.junit.jupiter.api.extension.BeforeEachCallback
import org.junit.jupiter.api.extension.ExtensionContext
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 = true
})
}
override fun afterEach(context: ExtensionContext?) {
ArchTaskExecutor.getInstance().setDelegate(null)
}
}
InstantExecutorExtension在本地单元测试中用注解实现class。
ContentViewModelTest.kt
...
import androidx.paging.PagedList
import com.google.firebase.Timestamp
import io.mockk.*
import org.assertj.core.api.Assertions.assertThat
import org.junit.jupiter.api.AfterAll
import org.junit.jupiter.api.BeforeAll
import org.junit.jupiter.api.BeforeEach
import org.junit.jupiter.api.Test
import org.junit.jupiter.api.extension.ExtendWith
@ExtendWith(InstantExecutorExtension::class)
class ContentViewModelTest {
val timestamp = getTimeframe(DAY)
@BeforeAll
fun beforeAll() {
mockkObject(ContentRepository)
}
@BeforeEach
fun beforeEach() {
clearAllMocks()
}
@AfterAll
fun afterAll() {
unmockkAll()
}
@Test
fun `Feed Load`() {
val content = Content("85", 0.0, Enums.ContentType.NONE, Timestamp.now(), "",
"", "", "", "", "", "", MAIN,
0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0)
every {
getMainFeedList(any(), any())
} returns MutableLiveData<Lce<ContentResult.PagedListResult>>().also { lce ->
lce.value = Lce.Content(
ContentResult.PagedListResult(
pagedList = MutableLiveData<PagedList<Content>>().apply {
this.value = listOf(content).asPagedList(
PagedList.Config.Builder().setEnablePlaceholders(false)
.setPrefetchDistance(24)
.setPageSize(12)
.build())
}, errorMessage = ""))
}
val contentViewModel = ContentViewModel(ContentRepository)
contentViewModel.processEvent(ContentViewEvent.FeedLoad(MAIN, DAY, timestamp, false))
assertThat(contentViewModel.feedViewState.getOrAwaitValue().contentList.getOrAwaitValue()[0])
.isEqualTo(content)
assertThat(contentViewModel.feedViewState.getOrAwaitValue().toolbar).isEqualTo(
ToolbarState(
visibility = GONE,
titleRes = app_name,
isSupportActionBarEnabled = false))
verify {
getMainFeedList(any(), any())
}
confirmVerified(ContentRepository)
}
}
如果 none 的解决方案在我的情况下效果相似，如果您使用的是更高版本的 Gradle 并且您使用的是 androidix，请确保从 导入androix 在你的构建 gradle.
implementation 'androidx.arch.core:core-testing:$version'
而不是
implementation 'android.arch.core:core-testing:$version'
我尝试在我的应用程序上测试一些方法，但在调用 mutablelivedata.postValue 时出现错误。这是一个片段和错误消息：
@Test
public void callStartScreenRepository(){
Observer<User> userObserver = mock(Observer.class);
startScreenViewModel.returnUser().observeForever(userObserver);
maennlich = new User();
maennlich.setVorname("Christian");
MutableLiveData<User> userTest = new MutableLiveData<>();
userTest.postValue(maennlich);
when(startScreenRepository.userWebService("testUser")).thenReturn(userTest);
verify(userObserver).onChanged(maennlich);
}
java.lang.RuntimeException：android.os.Looper 中的方法 getMainLooper 未被模拟。有关详细信息，请参阅 http://g.co/androidstudio/not-mocked。
at android.os.Looper.getMainLooper(Looper.java)
at android.arch.core.executor.DefaultTaskExecutor.postToMainThread(DefaultTaskExecutor.java:48)
at android.arch.core.executor.AppToolkitTaskExecutor.postToMainThread(AppToolkitTaskExecutor.java:100)
at android.arch.lifecycle.LiveData.postValue(LiveData.java:277)
at android.arch.lifecycle.MutableLiveData.postValue(MutableLiveData.java:28)
at com.example.cfrindt.foodtracking.ViewModels.StartScreenViewModelTest.callStartScreenRepository(StartScreenViewModelTest.java:102)
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.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.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.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access[=11=]0(ParentRunner.java:58)
at org.junit.runners.ParentRunner.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:117)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:42)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:262)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:84)
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.AppMain.main(AppMain.java:147)
无论我使用 setValue() 还是 postValue()，我都会收到此错误。 我怎样才能让它发挥作用？
首先，您需要使用 InstantTaskExecutorRule，这意味着：
@Rule public InstantTaskExecutorRule instantExecutorRule = new InstantTaskExecutorRule();
这将允许立即使用 MutableLiveData。请记住在您的应用的 build.gradle 中包含导入：
testCompile "android.arch.core:core-testing:$rootProject.ext.arch_version"
然后，您需要使用覆盖 RxSchedulers 的规则定义 JUnit 规则，或者在 @Before 中使用 RxAndroidPlugins 覆盖调度程序（如果您使用的是 RxJava）
RxSchedulersOverrideRule:
public class RxSchedulersOverrideRule implements TestRule {
@Override public Statement apply(final Statement base, Description description) {
return new Statement() {
@Override public void evaluate() throws Throwable {
RxAndroidPlugins.reset();
RxAndroidPlugins.setMainThreadSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.reset();
RxJavaPlugins.setIoSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.setComputationSchedulerHandler(scheduler -> Schedulers.trampoline());
RxJavaPlugins.setNewThreadSchedulerHandler(scheduler -> Schedulers.trampoline());
base.evaluate();
RxAndroidPlugins.reset();
RxJavaPlugins.reset();
}
};
}
}
并在测试中调用class:
@Rule public RxSchedulersOverrideRule rxSchedulersOverrideRule = new RxSchedulersOverrideRule();
另一个选项是在 @Before 的 setup() 中调用：
RxAndroidPlugins.setInitMainThreadSchedulerHandler(schedulerCallable -> Schedulers.trampoline());
使用后需要在@After's tearDownClass()中重新设置：
RxAndroidPlugins.reset();
@Carlos Daniel 的回答对我帮助很大，但面临另一个问题，即 Rule 未应用于 PowerMockRunner。对于那些有同样问题的人，这里是解决方案：
@RunWith(PowerMockRunner::class)
@PowerMockRunnerDelegate(MockitoJUnitRunner::class) //this line allows you to use the powermock runner and mockito runner
@PrepareForTest(UnderTestClass::class)
class UnderTestClassTest {
@get:Rule
var instantExecutorRule = InstantTaskExecutorRule()
确保观察者不在主线程上
Jeroen Mols outlines each implementation 适用于 JUnit 4 和 JUnit 5。我使用 Junit 5 方法使用 Kotlin、JUnit 5、MockK 和 AssertJ 库进行 Coinverse Open App 的本地单元测试。
JUnit 4
@Carlos Daniel 的 InstantExecutorRule 对于 JUnit 4 是正确的。
ExampleUnitTest.kt
class ExampleUnitTest {
@get:Rule
val rule = InstantTaskExecutorRule()
@Test
fun `my test`() {
val mutableLiveData = MutableLiveData<String>()
mutableLiveData.postValue("test")
assertEquals("test", mutableLiveData.value)
}
}
build.gradle
dependencies {
testImplementation 'android.arch.core:core-testing:X.X.X'
}
JUnit 5
InstantExecutorExtension.kt
import androidx.arch.core.executor.ArchTaskExecutor
import androidx.arch.core.executor.TaskExecutor
import org.junit.jupiter.api.extension.AfterEachCallback
import org.junit.jupiter.api.extension.BeforeEachCallback
import org.junit.jupiter.api.extension.ExtensionContext
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 = true
})
}
override fun afterEach(context: ExtensionContext?) {
ArchTaskExecutor.getInstance().setDelegate(null)
}
}
InstantExecutorExtension在本地单元测试中用注解实现class。
ContentViewModelTest.kt
...
import androidx.paging.PagedList
import com.google.firebase.Timestamp
import io.mockk.*
import org.assertj.core.api.Assertions.assertThat
import org.junit.jupiter.api.AfterAll
import org.junit.jupiter.api.BeforeAll
import org.junit.jupiter.api.BeforeEach
import org.junit.jupiter.api.Test
import org.junit.jupiter.api.extension.ExtendWith
@ExtendWith(InstantExecutorExtension::class)
class ContentViewModelTest {
val timestamp = getTimeframe(DAY)
@BeforeAll
fun beforeAll() {
mockkObject(ContentRepository)
}
@BeforeEach
fun beforeEach() {
clearAllMocks()
}
@AfterAll
fun afterAll() {
unmockkAll()
}
@Test
fun `Feed Load`() {
val content = Content("85", 0.0, Enums.ContentType.NONE, Timestamp.now(), "",
"", "", "", "", "", "", MAIN,
0, 0.0, 0.0, 0.0, 0.0,
0.0, 0.0, 0.0, 0.0)
every {
getMainFeedList(any(), any())
} returns MutableLiveData<Lce<ContentResult.PagedListResult>>().also { lce ->
lce.value = Lce.Content(
ContentResult.PagedListResult(
pagedList = MutableLiveData<PagedList<Content>>().apply {
this.value = listOf(content).asPagedList(
PagedList.Config.Builder().setEnablePlaceholders(false)
.setPrefetchDistance(24)
.setPageSize(12)
.build())
}, errorMessage = ""))
}
val contentViewModel = ContentViewModel(ContentRepository)
contentViewModel.processEvent(ContentViewEvent.FeedLoad(MAIN, DAY, timestamp, false))
assertThat(contentViewModel.feedViewState.getOrAwaitValue().contentList.getOrAwaitValue()[0])
.isEqualTo(content)
assertThat(contentViewModel.feedViewState.getOrAwaitValue().toolbar).isEqualTo(
ToolbarState(
visibility = GONE,
titleRes = app_name,
isSupportActionBarEnabled = false))
verify {
getMainFeedList(any(), any())
}
confirmVerified(ContentRepository)
}
}
如果 none 的解决方案在我的情况下效果相似，如果您使用的是更高版本的 Gradle 并且您使用的是 androidix，请确保从 导入androix 在你的构建 gradle.
implementation 'androidx.arch.core:core-testing:$version'
而不是
implementation 'android.arch.core:core-testing:$version'