No runnable methods on Android JUnit4 Instrumentation Tests

Question

I am new to Instrumentation Testing on Android and was learning from the sample at https://github.com/googlesamples/android-testing/tree/master/runner/AndroidJunitRunnerSample to use AndroidJUnit4.

That code works perfectly.

Trying to implement the same login on my project, however, I get the following exception:

Running tests
Test running started
java.lang.Exception: No runnable methods
at org.junit.runners.BlockJUnit4ClassRunner.validateInstanceMethods(BlockJUnit4ClassRunner.java:191)
at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:128)
at org.junit.runners.ParentRunner.validate(ParentRunner.java:416)
at org.junit.runners.ParentRunner.<init>(ParentRunner.java:84)
at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:65)
at android.support.test.internal.runner.junit4.AndroidJUnit4ClassRunner.<init>(AndroidJUnit4ClassRunner.java:38)
at android.support.test.runner.AndroidJUnit4.<init>(AndroidJUnit4.java:36)
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:288)
at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.buildAndroidRunner(AndroidAnnotatedBuilder.java:57)
at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.runnerForClass(AndroidAnnotatedBuilder.java:45)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
at org.junit.runner.Computer.getRunner(Computer.java:40)
at org.junit.runner.Computer$1.runnerForClass(Computer.java:31)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:101)
at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:87)
at org.junit.runners.Suite.<init>(Suite.java:81)
at org.junit.runner.Computer.getSuite(Computer.java:28)
at android.support.test.internal.runner.TestRequestBuilder.classes(TestRequestBuilder.java:791)
at android.support.test.internal.runner.TestRequestBuilder.build(TestRequestBuilder.java:754)
at android.support.test.runner.AndroidJUnitRunner.buildRequest(AndroidJUnitRunner.java:341)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:238)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853)

My AndroidTestSuite looks like:

import org.junit.runner.RunWith;
import org.junit.runners.Suite;

@RunWith(Suite.class)
@Suite.SuiteClasses({InstrumentationTestSuite.class})
public class AndroidTestSuite {}

And my InstrumentationTestSuite looks like:

import org.junit.runner.RunWith;
import org.junit.runners.Suite;

@RunWith(Suite.class)
@Suite.SuiteClasses({LoginInstrumentationTest.class})
public class InstrumentationTestSuite {}

My LoginInstrumentationTest is

@RunWith(AndroidJUnit4.class)
@LargeTest
public class LoginInstrumentationTest {

    @Rule
    public ActivityTestRule<LoginActivity> mActivityRule = new ActivityTestRule<>(
        LoginActivity.class);

    @Test
    public void attemptToLogin() {
        login("filipebarretto@xxxxxxxxxx.com", "12345678");
    }

    private void login(String email, String password) {

        // Enter user email
        onView(withId(R.id.email)).perform(typeText(email),
            closeSoftKeyboard());

        // Enter user password
        onView(withId(R.id.password)).perform(typeText(password),
            closeSoftKeyboard());

        // Click on the login button
        onView(withId(R.id.email_sign_in_button)).perform(click());

        // Testing
        onView(withId(R.id.email)).check(matches(withText(email)));

    }
}

From what I search, usually the error I'm getting is due to a missing @Test before my method.

The difference I noticed between my code and the one I'm learning from is the gradle version, which I use 1.5.0 and they use 2.0.0-beta2.

I also found that my Instrumentation.java that is called during the test has several "Cannot resolve symbol" error with I can't find the reason, since I use the same dependencies as the sample code.

Any one know what could be the reason of the No runnable methods exception and how to solve it?

Answer 1

I finally solved the problem. The problem was that I was planning on running unit tests also, not just instrumentation tests.

I had a class UnitTestSuite like:

import org.junit.runner.RunWith;
import org.junit.runners.Suite;

@RunWith(Suite.class)
@Suite.SuiteClasses({LoginUnitTest.class})
public class UnitTestSuite {}

And LoginUnitTest didn't implement any tests.

For some reason, even though UnitTestSuite wasn't called from AndroidTestSuite, it tried to run and returned No runnable methods, since LoginUnitTest had no tests implemented. I've added unit tests and now the tests work perfectly.