Android Espresso: Test running failed. No test results Empty test suite. Why?

Question

Can't make my Espresso UI test work. Where's the problem?
What result should I get for this simple app to consider that it's working?

I have "android.support.test.runner.AndroidJUnitRunner" for Instrumentation runner in Edit Confirurations .

From AndroidManifest.xml:

    <instrumentation
android:name="android.support.test.runner.AndroidJUnitRunner"
android:targetPackage="my.package"/>

From build.gradle:

defaultConfig {
    applicationId "my.package"
    minSdkVersion 18
    targetSdkVersion 22
    versionCode 1
    versionName "1.0"
    testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}

packagingOptions {
    exclude 'LICENSE.txt'}

repositories { jcenter()}

dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.2.0'
compile 'com.android.support:support-annotations:22.2.0'
androidTestCompile 'com.android.support.test:runner:0.3'
androidTestCompile 'com.android.support.test:rules:0.3'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'
androidTestCompile 'com.android.support.test.uiautomator:uiautomator-v18:2.1.1'
testCompile 'junit:junit:4.12'}

MainActivity.java

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final EditText editText = (EditText)findViewById(R.id.edit_text);
        Button button = (Button) findViewById(R.id.confirm);
        final TextView textView = (TextView)findViewById(R.id.you_entered);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                textView.setText("You entered: " + editText.getText());
            }
        });
    }
}

ApplicationTest.java

    public class ApplicationTest extends ApplicationTestCase<Application> {
    public ApplicationTest() {
        super(Application.class);
    }
}

MainActivityTest

public class MainActivityTest extends ActivityInstrumentationTestCase2 <MainActivity> {

    Activity activity;
    public MainActivityTest() {
        super(MainActivity.class);
    }

    @Override
    public void setUp() throws Exception {
        super.setUp();
        activity = getActivity();
    }

    @SmallTest
    public void testInputOutput() {
        Espresso.onView(ViewMatchers.withId(R.id.edit_text)).perform(ViewActions.click())
                .perform(ViewActions.typeText("Espresso"));
        Espresso.onView(ViewMatchers.withId(R.id.confirm)).perform(ViewActions.click());
        Espresso.onView(ViewMatchers.withId(R.id.you_entered)).check(ViewAssertions.matches
                (ViewMatchers.withText("Espresso")));
        assertEquals(((TextView)ViewMatchers.withId(R.id.you_entered)).getText(), "Espresso");
    }
}

The results of running all tests:

Testing started at 12:36 ...
Installing my.package
DEVICE SHELL COMMAND: pm install -r "/data/local/tmp/my.package"
pkg: /data/local/tmp/my.package
Success

Uploading file
    local path: /home/jane_doe/project/android/MyTestApp/app/build/outputs/apk/app-debug-androidTest-unaligned.apk
    remote path: /data/local/tmp/my.package.test
Installing my.package.test
DEVICE SHELL COMMAND: pm install -r "/data/local/tmp/my.package.test"
pkg: /data/local/tmp/my.package.test
Success

Running tests
Test running startedTest running failed: No test results
Empty test suite.

The result of running MainActivityTest only:

Testing started at 12:39 ...
12:39:39: Executing external tasks 'cleanTest test --tests cosysoft.cupofcoffee.MainActivityTest'...
:app:cleanTest UP-TO-DATE
:app:preBuild UP-TO-DATE
:app:preDebugBuild UP-TO-DATE
:app:checkDebugManifest
:app:preReleaseBuild UP-TO-DATE
:app:prepareComAndroidSupportAppcompatV72220Library UP-TO-DATE
:app:prepareComAndroidSupportSupportV42220Library UP-TO-DATE
:app:prepareDebugDependencies
:app:compileDebugAidl UP-TO-DATE
:app:compileDebugRenderscript UP-TO-DATE
:app:generateDebugBuildConfig UP-TO-DATE
:app:generateDebugAssets UP-TO-DATE
:app:mergeDebugAssets UP-TO-DATE
:app:generateDebugResValues UP-TO-DATE
:app:generateDebugResources UP-TO-DATE
:app:mergeDebugResources UP-TO-DATE
:app:processDebugManifest UP-TO-DATE
:app:processDebugResources UP-TO-DATE
:app:generateDebugSources UP-TO-DATE
:app:processDebugJavaRes UP-TO-DATE
:app:compileDebugJava UP-TO-DATE
:app:preCompileDebugUnitTestJava
:app:preDebugUnitTestBuild UP-TO-DATE
:app:prepareDebugUnitTestDependencies
:app:processDebugUnitTestJavaRes UP-TO-DATE
:app:compileDebugUnitTestJava UP-TO-DATE
:app:compileDebugUnitTestSources UP-TO-DATE
:app:mockableAndroidJar UP-TO-DATE
:app:assembleDebugUnitTest UP-TO-DATE
:app:testDebug
:app:testDebug FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:testDebug'.
> No tests found for given includes: [my.package.MainActivityTest]
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
BUILD FAILED
Total time: 3.079 secs
No tests found for given includes: [my.package.MainActivityTest]

Answer 1

Note that you are using the deprecated ActivityInstrumentationTestCase2 and that

TestCases like ActivityInstrumentationTestCase2 or ServiceTestCase are deprecated in favor of ActivityTestRule or ServiceTestRule.

So try switchwing to using the rules , which is actually pretty straightforward. Also, be sure to use the correct annotations. Check my other answer here to get more useful references.