在我的应用程序中我调用了ContextCompat.getExternalFilesDirs，我的Robolectric测试因以下堆栈跟踪而失败：
java.lang.NoSuchMethodError: android.content.Context.getExternalFilesDirs(Ljava/lang/String;)[Ljava/io/File;
at android.support.v4.content.ContextCompatKitKat.getExternalFilesDirs(ContextCompatKitKat.java:29)
at android.support.v4.content.ContextCompat.getExternalFilesDirs(ContextCompat.java:216)
at com.mondiamedia.mmplaylistapp.helpers.SongFileHelper.getMyPlaylistSongsFolder(SongFileHelper.java:73)
at com.mondiamedia.mmplaylistapp.helpers.SongFileHelper.getNewMyPlaylistSongFile(SongFileHelper.java:48)
at com.mondiamedia.mmplaylistapp.helpers.SongFileHelperTest.testGetNewMyPlaylistSongFileWithValidSong(SongFileHelperTest.java:60)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
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.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.robolectric.RobolectricTestRunner$2.evaluate(RobolectricTestRunner.java:250)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.robolectric.RobolectricTestRunner$1.evaluate(RobolectricTestRunner.java:177)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.runTestClass(JUnitTestClassExecuter.java:86)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.execute(JUnitTestClassExecuter.java:49)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassProcessor.processTestClass(JUnitTestClassProcessor.java:69)
at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.processTestClass(SuiteTestClassProcessor.java:50)
at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.messaging.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:32)
at org.gradle.messaging.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
at com.sun.proxy.$Proxy2.processTestClass(Unknown Source)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.processTestClass(TestWorker.java:103)
at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.messaging.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:355)
at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:64)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
我查看了ContextCompat.java，罪魁祸首似乎是这部分：
final int version = Build.VERSION.SDK_INT;
if (version >= 19) {
return ContextCompatKitKat.getExternalFilesDirs(context, type);
} else {
final File single;
if (version >= 8) {
single = ContextCompatFroyo.getExternalFilesDir(context, type);
在测试中我放了@Config（emulateSdk = 18），但似乎Robolectric仍然以SDK 19运行它，因此调用ContextCompatKitKat类。有谁知道如何防止这个错误？显而易见的解决方案是调用ContextCompatFroyo，但我不知道是否有任何不必要的副作用。