espresso-support

Includes custom rules for testing Views in isolation and running tests with Google TalkBack enabled.

The library is split into two components:

• core - main espresso dependency (androidTestCompile)
• extras - optional, depending on which classes you use (debugCompile/espressoCompile)

The extras dependency adds some components to your app (hence it's not androidTestCompile), e.g. the ViewActivity.

Usage

The artifacts are available on JCenter:

debugCompile 'com.novoda:espresso-support-extras:<latest-version>'
androidTestCompile 'com.novoda:espresso-support:<latest-version>'

Testing views in isolation

Use the ViewTestRule, passing in a layout resource. It'll inflate the resource into the ViewActivity with MATCH_PARENT for both dimensions. You can use rule.getView() to obtain an instance of the View and it'll be typed to the class you specified.

@Rule
public ViewTestRule<MovieItemView> rule = new ViewTestRule<>(R.layout.test_movie_item_view);

You can write BDD style tests here, highlighting the expected behaviour for your custom views, using a mixture of Espresso ViewActions and Mockito verifies:

@Test
public void givenViewIsUpdatedWithDifferentMovie_whenClicking_thenListenerDoesNotGetFiredForOriginalMovie() {
    givenMovieItemViewIsBoundTo(EDWARD_SCISSORHANDS);
    givenMovieItemViewIsBoundTo(NOT_EDWARD_SCISSORHANDS);

    onView(withId(R.id.movie_item_button_play)).perform(click());

    verify(movieItemListener, never()).onClickPlay(eq(EDWARD_SCISSORHANDS));
}

private void givenMovieItemViewIsBoundTo(final Movie movie) {
    viewTestRule.runOnUiThread(new ViewTestRule.UiThreadAction<MovieItemView>() {
        @Override
        public void run(MovieItemView view) {
            view.bind(movie);
        }
    });
}

⚠️ This rule requires the extras module to be included for the app under test, so it can open the ViewActivity.

Testing behaviour with TalkBack enabled

Often, our apps will behave differently when TalkBack is enabled to offer a more streamlined experience for users of screen readers.

Use either TalkBackViewTestRule or TalkBackActivityTestRule - TalkBack will be enabled before each test is run and disabled after each test finishes.

⚠️ This rule requires the extras module to be included for the app under test, so it can open the TalkBackStateSettingActivity. :warning: Toggling TalkBack state requires the WRITE_SECURE_SETTINGS permission being set for the app under test.

adb shell pm grant com.novoda.movies android.permission.WRITE_SECURE_SETTINGS

If the app is installed and the permission granted, you can enable/disable TalkBack via adb with the following actions:

$ adb shell am start -a "com.novoda.espresso.ENABLE_TALKBACK"
$ adb shell am start -a "com.novoda.espresso.DISABLE_TALKBACK"

You can also do the same with an Intent:

Intent intent = new Intent("com.novoda.espresso.ENABLE_TALKBACK")
context.startActivity(intent);

Demo

You can run the demo tests with the following commands:

./gradlew demo:installDebug; adb shell pm grant com.novoda.movies android.permission.WRITE_SECURE_SETTINGS; adb shell am start -a "com.novoda.espresso.DISABLE_TALKBACK"; ./gradlew demo:cAT; adb shell am start -a "com.novoda.espresso.DISABLE_TALKBACK";

You have to install the app first to set the permission. We also disable TalkBack before and after the tests so we don't mess up non-TalkBack tests.

Links

Here are a list of useful links:

• We always welcome people to contribute new features or bug fixes, here is how
• If you have a problem check the Issues Page first to see if we are working on it // TODO: waiting on repo to exist