Example custom test runner crashes

The README.md states to do:

public class ExampleTestRunner extends AndroidJUnitRunner {
  @Override
  public void onStart() {
      TestButler.setup(ApplicationProvider.getApplicationContext());
      super.onStart();
  }

  @Override
  public void finish(int resultCode, Bundle results) {
      TestButler.teardown(ApplicationProvider.getApplicationContext());
      super.finish(resultCode, results);
  }
}

however, this crashed for me with androidX’s test-core v1.0.0 with this:

java.lang.IllegalStateException: No instrumentation registered! Must run under a registering instrumentation.
   at androidx.test.platform.app.InstrumentationRegistry.getInstrumentation(InstrumentationRegistry.java:45)
   at androidx.test.core.app.ApplicationProvider.getApplicationContext(ApplicationProvider.java:41)
   at my.custom.AndroidJUnitRunner.onStart(AndroidJUnitRunner.kt:11)
   at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:2145)

so I figured this might be a race here that the registry doesn’t know of the instrumentation yet. It is however totally unneccessary to use the registry at all, since the runner itself is the instrumentation that we need, so it is sufficient to do this:

public class ExampleTestRunner extends AndroidJUnitRunner {
  @Override
  public void onStart() {
      TestButler.setup(getTargetContext());
      super.onStart();
  }

  @Override
  public void finish(int resultCode, Bundle results) {
      TestButler.teardown(getTargetContext());
      super.finish(resultCode, results);
  }
}

This properly initialized TestButler for me, i.e. disabled animations, and ran my tests.

[realdadfish]

No, ApplicationProvider.getApplicationContext() just redirects to the InstrumentationRegistry, this won’t help. I’m suggesting to use the created application context of the runner itself, since AndroidJUnitRunner extends from Instrumentation.

[mennatallah]

I have the same issue when I’m trying to Run my feature file as iam using a cucumber integrated with Espresso for Android UI java.lang.IllegalStateException: No instrumentation registered! Must run under a registering instrumentation. at androidx.test.platform.app.InstrumentationRegistry.getInstrumentation(InstrumentationRegistry.java:45)