I've been running some tests on an android application using Robolectric and it's been working well until now.
My application passes the result of getApplicationContext() to a constructor, but Robolectric should be ensuring the value of this is not null as I am using the BuildActivity() method. The error is in some configuration of my test environment, or a bug in Robolectric. The result is a NullPointerException in the constructor of Toast.
My environment:
com.android.tools.build:gradle:3.0.1
org.robolectric:robolectric:3.4.2
junit:junit:4.12
I'm trying to test our class SystemMonitorActivity, which is abstract
public abstract class SystemMonitorActivity extends BaseActivity implements OnClickListener
BaseActivity:
public class BaseActivity extends Activity implements IHandleMessageReceived, Thread.UncaughtExceptionHandler
I've created a subclass of SystemMonitorActivity so that I can instantiate it in my tests:
public class SystemMonitorActivitySubclass extends SystemMonitorActivity
Here is my mock test class to reproduce the error I am seeing:
@RunWith(RobolectricTestRunner.class)
@Config(constants = BuildConfig.class)
public class BuildActivityTest {
@Test
public void onCreateTest000() throws Exception {
SystemMonitorActivitySubclass systemMonitorActivitySubclass = Robolectric.buildActivity(SystemMonitorActivitySubclass.class).create().get();
}
}
My test output:
java.lang.NullPointerException
at android.widget.Toast.__constructor__(Toast.java:114)
at android.widget.Toast.<init>(Toast.java)
at org.robolectric.shadows.ShadowToast.makeText(ShadowToast.java:38)
at android.widget.Toast.makeText(Toast.java)
at com.siemens.hc.poc.isf.admin.sysmon.SystemMonitorActivity.setUpDeviceOwner(SystemMonitorActivity.java:649)
at com.siemens.hc.poc.isf.admin.sysmon.SystemMonitorActivity.onCreate(SystemMonitorActivity.java:401)
at android.app.Activity.performCreate(Activity.java:6975)
at org.robolectric.util.ReflectionHelpers.callInstanceMethod(ReflectionHelpers.java:232)
at org.robolectric.android.controller.ActivityController$1.run(ActivityController.java:73)
at org.robolectric.shadows.ShadowLooper.runPaused(ShadowLooper.java:366)
at org.robolectric.shadows.CoreShadowsAdapter$1.runPaused(CoreShadowsAdapter.java:27)
at org.robolectric.android.controller.ActivityController.create(ActivityController.java:70)
at org.robolectric.android.controller.ActivityController.create(ActivityController.java:80)
at com.siemens.hc.poc.isf.admin.sysmon.BuildActivityTest.setUp(BuildActivityTest.java:63)
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.statements.RunBefores.evaluate(RunBefores.java:24)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.robolectric.internal.SandboxTestRunner$2.evaluate(SandboxTestRunner.java:228)
at org.robolectric.internal.SandboxTestRunner.runChild(SandboxTestRunner.java:110)
at org.robolectric.internal.SandboxTestRunner.runChild(SandboxTestRunner.java:37)
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.robolectric.internal.SandboxTestRunner$1.evaluate(SandboxTestRunner.java:64)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.runTestClass(JUnitTestClassExecuter.java:114)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.execute(JUnitTestClassExecuter.java:57)
at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassProcessor.processTestClass(JUnitTestClassProcessor.java:66)
at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.processTestClass(SuiteTestClassProcessor.java:51)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:32)
at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
at com.sun.proxy.$Proxy1.processTestClass(Unknown Source)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.processTestClass(TestWorker.java:108)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:146)
at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:128)
at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:404)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
at java.lang.Thread.run(Thread.java:748)
I've made sure to include the Android resources in my tests in build.gradle:
android.testOptions.unitTests.includeAndroidResources = true
Could it be that I need to add SystemMonitorActivitySubclass to the AndroidManifest.xml somehow?
Working our way through the stack trace, the actual NPE occurs in this snippet of code:
java.lang.NullPointerException
at android.widget.Toast.__constructor__(Toast.java:114)
public Toast(@NonNull Context context, @Nullable Looper looper) {
mContext = context;
mTN = new TN(context.getPackageName(), looper);
...
Which is called from Robolectrics ShadowToast:
at android.widget.Toast.<init>(Toast.java)
at org.robolectric.shadows.ShadowToast.makeText(ShadowToast.java:38)
@Implementation
public static Toast makeText(Context context, CharSequence text, int duration) {
Toast toast = new Toast(context);
...
Context being passed to makeText is getApplicationContext(), which should be handled by Robolectric to ensure it is not null:
at android.widget.Toast.makeText(Toast.java)
at com.siemens.hc.poc.isf.admin.sysmon.SystemMonitorActivity.setUpDeviceOwner(SystemMonitorActivity.java:649)
Toast.makeText(getApplicationContext(), "Not a device owner", Toast.LENGTH_SHORT).show();
I've been debugging this for 6+ hours now and I don't feel any closer to figuring out what the issue is. Any help is much appreciated, thanks!
UPDATE: I've tried the following approach as suggested by Anton Malyshev
@Test
public void onCreateTest000() throws Exception {
ActivityController controller = Robolectric.buildActivity(SystemMonitorActivitySubclass.class).create().start();
Activity activity = (Activity)controller.get();
}
This has the same result;
java.lang.NullPointerException
at android.widget.Toast.__constructor__(Toast.java:114)
