为什么在使用 Robolectric 的 Android 单元测试中调用 HtmlCompat 时会出现 ExceptionInInitializerError？

Question

我正在尝试对属于 Android 应用程序用例层一部分的方法进行单元测试。 该方法接收 XML RSS 提要并将其作为 GSON 解析对象返回到视图 model。 测试 class 用@RunWith(RobolectricTestRunner::class)注释。

测试失败是因为java.lang.ExceptionInInitializerError （以及其他）在用例 class 的这个方法中被.fromHtml()抛出：

    private fun convertHtml(rawString: String): String {
    return HtmlCompat
        .fromHtml(rawString, HtmlCompat.FROM_HTML_MODE_COMPACT)
        .toString()
        .replace("", "")
        .trim()
}

在阅读堆栈跟踪时，这似乎是 Robolectric 尝试初始化 static 方法或 class 的问题？ 我这样说是因为堆栈跟踪中的一些行，例如：

    at org.robolectric.internal.bytecode.RobolectricInternals.performStaticInitialization(RobolectricInternals.java:61)
    at org.robolectric.internal.bytecode.ShadowWrangler.classInitializing(ShadowWrangler.java:178)

不幸的是，我所有的研究都无济于事。 我似乎找不到与此问题相关的任何内容。 我已经看到几个线程讨论一起使用 Robolectric 和 PowerMock 来测试 static 个类，尽管我不确定这是否是相关方法，并且我想尽可能避免添加更多测试框架。 为什么抛出这个异常，如何解决这个异常？

作为参考，这里是整个堆栈跟踪：

java.lang.ExceptionInInitializerError
    at android.text.SpannableStringBuilder.__constructor__(SpannableStringBuilder.java:61)
    at android.text.SpannableStringBuilder.<init>(SpannableStringBuilder.java)
    at android.text.HtmlToSpannedConverter.__constructor__(Html.java:425)
    at android.text.HtmlToSpannedConverter.<init>(Html.java)
    at android.text.Html.fromHtml(Html.java:135)
    at android.text.Html.fromHtml(Html.java:101)
    at androidx.core.text.HtmlCompat.fromHtml(HtmlCompat.java:150)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertHtml(GetNewsHeadlinesUseCase.kt:162)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertXmlToJson(GetNewsHeadlinesUseCase.kt:80)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.execute(GetNewsHeadlinesUseCase.kt:35)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest$parsing success$1.invokeSuspend(GetNewsHeadlinesUseCaseTest.kt:33)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
    at kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:279)
    at kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
    at kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
    at kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest.parsing success(GetNewsHeadlinesUseCaseTest.kt:32)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
    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$3.evaluate(ParentRunner.java:306)
    at org.robolectric.RobolectricTestRunner$HelperTestRunner$1.evaluate(RobolectricTestRunner.java:570)
    at org.robolectric.internal.SandboxTestRunner$2.lambda$evaluate$0(SandboxTestRunner.java:278)
    at org.robolectric.internal.bytecode.Sandbox.lambda$runOnMainThread$0(Sandbox.java:89)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
    at org.robolectric.internal.bytecode.ShadowWrangler.classInitializing(ShadowWrangler.java:181)
    at org.robolectric.internal.bytecode.RobolectricInternals.classInitializing(RobolectricInternals.java:21)
    at android.text.TextUtils.<clinit>(TextUtils.java)
    at android.text.SpannableStringBuilder.$$robo$$android_text_SpannableStringBuilder$__constructor__(SpannableStringBuilder.java:61)
    at android.text.SpannableStringBuilder.<init>(SpannableStringBuilder.java)
    at android.text.SpannableStringBuilder.<init>(SpannableStringBuilder.java)
    at android.text.SpannableStringBuilder.<init>(SpannableStringBuilder.java)
    at android.text.HtmlToSpannedConverter.$$robo$$android_text_HtmlToSpannedConverter$__constructor__(Html.java:425)
    at android.text.HtmlToSpannedConverter.<init>(Html.java)
    at android.text.Html.$$robo$$android_text_Html$fromHtml(Html.java:135)
    at android.text.Html.fromHtml(Html.java)
    at android.text.Html.$$robo$$android_text_Html$fromHtml(Html.java:101)
    at android.text.Html.fromHtml(Html.java)
    at androidx.core.text.HtmlCompat.fromHtml(HtmlCompat.java:150)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertHtml(GetNewsHeadlinesUseCase.kt:162)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertXmlToJson(GetNewsHeadlinesUseCase.kt:80)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.execute(GetNewsHeadlinesUseCase.kt:35)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest$parsing success$1.invokeSuspend(GetNewsHeadlinesUseCaseTest.kt:33)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
    at kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:279)
    at kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
    at kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
    at kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest.parsing success(GetNewsHeadlinesUseCaseTest.kt:32)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    ... 13 more
Caused by: java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.robolectric.internal.bytecode.RobolectricInternals.performStaticInitialization(RobolectricInternals.java:61)
    at org.robolectric.internal.bytecode.ShadowWrangler.classInitializing(ShadowWrangler.java:178)
    ... 43 more
Caused by: java.lang.NullPointerException
    at org.robolectric.shadows.ShadowLegacyAssetManager.getAndResolve(ShadowLegacyAssetManager.java:1019)
    at org.robolectric.shadows.ShadowLegacyAssetManager.getResourceText(ShadowLegacyAssetManager.java:285)
    at android.content.res.AssetManager.getResourceText(AssetManager.java)
    at android.content.res.Resources.getText(Resources.java:225)
    at android.content.res.Resources.getString(Resources.java:313)
    at android.text.TextUtils.__staticInitializer__(TextUtils.java:1704)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at org.robolectric.internal.bytecode.RobolectricInternals.performStaticInitialization(RobolectricInternals.java:61)
    at org.robolectric.internal.bytecode.ShadowWrangler.classInitializing(ShadowWrangler.java:178)
    at org.robolectric.internal.bytecode.RobolectricInternals.classInitializing(RobolectricInternals.java:21)
    at android.text.TextUtils.<clinit>(TextUtils.java)
    at android.text.SpannableStringBuilder.__constructor__(SpannableStringBuilder.java:61)
    at android.text.SpannableStringBuilder.<init>(SpannableStringBuilder.java)
    at android.text.HtmlToSpannedConverter.__constructor__(Html.java:425)
    at android.text.HtmlToSpannedConverter.<init>(Html.java)
    at android.text.Html.fromHtml(Html.java:135)
    at android.text.Html.fromHtml(Html.java:101)
    at androidx.core.text.HtmlCompat.fromHtml(HtmlCompat.java:150)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertHtml(GetNewsHeadlinesUseCase.kt:162)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.convertXmlToJson(GetNewsHeadlinesUseCase.kt:80)
    at com.domg.testrss.domain.usecase.GetNewsHeadlinesUseCase.execute(GetNewsHeadlinesUseCase.kt:35)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest$parsing success$1.invokeSuspend(GetNewsHeadlinesUseCaseTest.kt:33)
    at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
    at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
    at kotlinx.coroutines.EventLoopImplBase.processNextEvent(EventLoop.common.kt:279)
    at kotlinx.coroutines.BlockingCoroutine.joinBlocking(Builders.kt:85)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking(Builders.kt:59)
    at kotlinx.coroutines.BuildersKt.runBlocking(Unknown Source)
    at kotlinx.coroutines.BuildersKt__BuildersKt.runBlocking$default(Builders.kt:38)
    at kotlinx.coroutines.BuildersKt.runBlocking$default(Unknown Source)
    at com.domg.testrss.GetNewsHeadlinesUseCaseTest.parsing success(GetNewsHeadlinesUseCaseTest.kt:32)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    ... 13 more

Answer 1

我发现了一个解决方案。 将以下内容添加到模块build.gradle的android部分：

    testOptions {
        unitTests {
            includeAndroidResources = true
        }
    }

根据文档，将此设置为 true 将允许单元测试通过“在运行单元测试之前执行[ing]资源、资产和清单合并”来“使用 Android 资源、资产和清单”。

一旦我如上所述添加了它，异常就会停止并且我调用HtmlCompat的单元测试能够完成。