Robolectric启动时反射的NullPointerException - 任何提示？

Question

我正在Eclipse上开发一个Android项目,我正在尝试从模拟器/设备(非常慢)上的运行测试切换到Robolectric.

我用Robolectric取代了Android库,将JUnit添加到路径中,将测试用例更改回常规TestCase并添加@RunWith(RobolectricTestRunner.class)了快速入门指南中的建议(进行必要的更改以实例化我的Activity而不是依赖于Android的活动测试来执行此操作为了我).

但是,当我运行测试时,我得到:

java.lang.NullPointerException
 at com.xtremelabs.robolectric.RobolectricTestRunner.isInstrumented(RobolectricTestRunner.java:123)
 at com.xtremelabs.robolectric.RobolectricTestRunner.<init>(RobolectricTestRunner.java:72)
 at com.xtremelabs.robolectric.RobolectricTestRunner.<init>(RobolectricTestRunner.java:57)
 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
 at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
 at java.lang.reflect.Constructor.newInstance(Constructor.java:532)
 at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:31)
 at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:24)
 at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
 at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29)
 at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
 at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:24)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.<init>(JUnit4TestReference.java:29)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.<init>(JUnit4TestClassReference.java:25)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:40)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:30)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:452)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

这似乎与此代码有关(来自0.9标签,因为0.9.1标签没有它)RobolectricTestRunner.java:

private static boolean isInstrumented() {
    return RobolectricTestRunner.class.getClassLoader().getClass().getName().contains(RobolectricClassLoader.class.getName());
}

但我无法理解,因为这种反思应该来自班级本身.

此外,我可以发誓它在重复失败之前运行了一次 - 我已经删除了robolectric缓存(如此处所示)并用最新版本(4.8.2)替换了Eclipse的JUnit,但没有任何改变.

任何提示？

更新:我尝试创建一个新的Java(即普通的,非Android)测试项目,就像快速入门指南中所述.但是,现在测试运行抱怨没有AndroidManifest.xml:

java.lang.RuntimeException: java.io.FileNotFoundException: /Users/chester/Documents/workspace/minitruco-android/minitruco-android-robolectric-test/AndroidManifest.xml (No such file or directory)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:245)
    at com.xtremelabs.robolectric.RobolectricTestRunner.setupApplicationState(RobolectricTestRunner.java:215)
    at com.xtremelabs.robolectric.RobolectricTestRunner.internalBeforeTest(RobolectricTestRunner.java:163)
    at com.xtremelabs.robolectric.RobolectricTestRunner.methodBlock(RobolectricTestRunner.java:143)
    at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.io.FileNotFoundException: /Users/chester/Documents/workspace/minitruco-android/minitruco-android-robolectric-test/AndroidManifest.xml (No such file or directory)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(FileInputStream.java:137)
    at java.io.FileInputStream.<init>(FileInputStream.java:96)
    at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:87)
    at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:178)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLVersionDetector.determineDocVersion(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    at javax.xml.parsers.DocumentBuilder.parse(Unknown Source)
    at com.xtremelabs.robolectric.RobolectricTestRunner.findResourcePackageName(RobolectricTestRunner.java:255)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:236)
    ... 18 more

我想测试应该从原始项目(minitruco-android)加载文件,这些文件显示在测试项目的构建路径和Eclipse上的Run/Debug构建配置中(在测试项目的类路径条目下).无论如何,我已经复制了我原来的测试项目(只是为了测试的缘故)的文件,但随后抱怨R.java(和那确实应该已经从原来的项目进口):

java.lang.RuntimeException: java.lang.ClassNotFoundException: caught an exception while obtaining a class file for me.chester.minitruco.test.R
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:245)
    at com.xtremelabs.robolectric.RobolectricTestRunner.setupApplicationState(RobolectricTestRunner.java:215)
    at com.xtremelabs.robolectric.RobolectricTestRunner.internalBeforeTest(RobolectricTestRunner.java:163)
    at com.xtremelabs.robolectric.RobolectricTestRunner.methodBlock(RobolectricTestRunner.java:143)
    at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.ClassNotFoundException: caught an exception while obtaining a class file for me.chester.minitruco.test.R
    at javassist.Loader.findClass(Loader.java:359)
    at com.xtremelabs.robolectric.RobolectricClassLoader.findClass(RobolectricClassLoader.java:60)
    at javassist.Loader.loadClass(Loader.java:311)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:268)
    at com.xtremelabs.robolectric.RobolectricClassLoader.loadClass(RobolectricClassLoader.java:37)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:336)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:186)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:237)
    ... 18 more
Caused by: javassist.NotFoundException: me.chester.minitruco.test.R
    at javassist.ClassPool.get(ClassPool.java:436)
    at com.xtremelabs.robolectric.AndroidTranslator.onLoad(AndroidTranslator.java:68)
    at javassist.Loader.findClass(Loader.java:340)
    ... 26 more

我的设置和快速启动之间唯一不同的是我在测试项目和常规项目的常规源上保留测试源(自第一次构建以来,我假设测试项目看到常规源 - 这些,当然,这在很大程度上取决于).

我正在使用SoyLatte,但也尝试了Mac OS的默认1.6 JVM,结果相同.

谢谢.

Answer 1

我们过去也遇到过同样的问题.对我们有用的是扩展RoboletricTestRunner并为其提供一个了解我们项目位置的RoboletricConfig实例.这样我就不必修改任何运行配置与eclipse,它只是工作.

    package ...;

    import java.io.File;

    import org.junit.runners.model.InitializationError;

    import com.xtremelabs.robolectric.RobolectricConfig;
    import com.xtremelabs.robolectric.RobolectricTestRunner;

    public class TestRunner extends RobolectricTestRunner {

        public static final string MAIN_PROJECT_PATH = "../path_to_android_project";

        public TestRunner(Class<?> testClass) throws InitializationError {
             super(testClass, new RobolectricConfig(new File(MAIN_PROJECT_PATH)));
        }
    }

Answer 2

通常你不需要扩展TestCase,但我认为不应该导致这个问题.你能否包括失败测试的来源？

关于更新中的简化项目,请确保将Eclipse配置为将当前工作目录设置为主项目的根目录,而不是测试项目,因此它将找到AndroidManifest.xml和res目录.