Slide 1
Slide 1 text
Effective
Espresso
Misumi_Rize
Roppongi.aar #2 (Nov. 17, 2015)
Slide 2
Slide 2 text
Log.d("introduction", me);
→ Twitter @Misumi_Rize
→ GitHub @MisumiRize
→ I'm not Android APK developer
Slide 3
Slide 3 text
My previous presentation
Slide 4
Slide 4 text
First of all:
androidTest !=
Espresso
Slide 5
Slide 5 text
Espresso is...
→ High level wrapper of Instrumentation
→ High level wrapper of InputEvent
→ View assertion
Slide 6
Slide 6 text
You can test them with Espresso
→ View interaction
→ Activity transition
Slide 7
Slide 7 text
Espresso Pros.
→ You can stub out unnecessary APIs
→ Simple synchronous interaction API
→ Built-in matchers
Slide 8
Slide 8 text
Espresso Cons.
→ Requires slow simulator or real device
→ Long test problem
→ Built-in matchers
Slide 9
Slide 9 text
Use case of Espresso
→ Activity integration test
→ Do not test everything using Espresso
→ Avoid writing too many tests using Espresso
Slide 10
Slide 10 text
Start Using
Espresso
Slide 11
Slide 11 text
build.gradle
android {
defaultConfig {
// ...
testInstrumentationRunner 'android.support.test.runner.AndroidJUnitRunner'
}
// ...
packagingOptions {
exclude 'LICENSE.txt'
}
}
dependencies {
// ...
androidTestCompile 'com.android.support.test:runner:0.4.1'
androidTestCompile 'com.android.support.test:rules:0.4.1'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.1'
}
Slide 12
Slide 12 text
Run with JUnit 4
@RunWith(AndroidJUnit4Runner.class)
public class MainActivityTest {
@Rule
public ActivityTestRule activityRule
= new ActivityTestRule<>(MainActivity.class);
@Test
public void submitButtonIsDisplayed() {
Espresso.onView(ViewMatchers.withId(R.id.submit_button))
.check(ViewAssertions.isDisplayed());
}
}
Slide 13
Slide 13 text
Note
→ @Rule is just JUnit lifecycle hook
→ You can also launch Activity manually
→ You can also assert regular JUnit way
Slide 14
Slide 14 text
Composite ViewMatchers
→ ViewMatchers.hasText()
→ ViewMatchers.hasSibling()
→ allOf(), oneOf()
Slide 15
Slide 15 text
Capture
Intents
Slide 16
Slide 16 text
build.gradle
dependencies {
// ...
androidTestCompile 'com.android.support.test.espresso:espresso-intents:2.2.1'
}
Slide 17
Slide 17 text
Intent matching
@Test
public void testTransitingToBrowser() {
Espresso.onView(ViewMatchers.withId(R.id.launch_browser))
.perform(ViewActions.click());
Intents.intended(
Matchers.allOf(
IntentMatchers.hasAction(IsEqual.equalTo(Intent.ACTION_VIEW)),
IntentMatchers.hasData("https://google.com")
)
);
}
Slide 18
Slide 18 text
Async
Handling
Slide 19
Slide 19 text
build.gradle
dependencies {
// ...
androidTestCompile 'com.android.support.test.espresso:espresso-idling-resource:2.2.1'
}
Slide 20
Slide 20 text
public class MyIdlingResource implements IdlingResource {
private ResourceCallback resourceCallback;
private idle = true;
@Override
public String getName() {
return IntentServiceIdlingResource.class.getName();
}
@Override
public void registerIdleTransitionCallback(ResourceCallback resourceCallback) {
this.resourceCallback = resourceCallback;
}
@Override
public boolean isIdleNow() {
if (idle && resourceCallback != null) {
resourceCallback.onTransitionToIdle();
}
return idle;
}
public void setIdle(boolean idle) {
this.idle = idle;
}
}
Slide 21
Slide 21 text
On test
@Test
public void testHandleAsync() {
MyIdlingResource idlingResource = new MyIdlingResource();
Espresso.registerIdlingResources(idlingResource);
// Do something
// Do not forget unregister idlingResource
Espresso.unregisterIdlingResources(idlingResource);
}
Slide 22
Slide 22 text
Don't Repeat
Yourself
Slide 23
Slide 23 text
DRY
→ Separate content from code
→ Make refactoring easy
Slide 24
Slide 24 text
@Test
public void submitButtonIsDisplayed() {
submitButton().check(
ViewAssertions.isDisplayed()
);
}
private ViewInteraction submitButton() {
return Espresso.onView(
ViewMatchers.withText("Submit")
);
}
Slide 25
Slide 25 text
Random Data
Slide 26
Slide 26 text
Use Faker
→ More natural user data
→ Bootstrappable (zip code, address)
→ Internet-friendly (email, domain)
Slide 27
Slide 27 text
build.gradle
dependencies {
// ...
androidTestCompile 'com.github.javafaker:javafaker:0.6'
}
Slide 28
Slide 28 text
private Faker faker;
@Before
public void setUp() {
faker = new Faker();
}
@Test
public void inputEmailAddress() {
editEmailAddress()
.perform(ViewActions.sendKeys(emailAddress()));
}
private String emailAddress() {
return faker.internet().emailAddress();
}
Slide 29
Slide 29 text
Use With
Lambda
Slide 30
Slide 30 text
Lambda on Android
→ Shorten anonymous class declaration
→ Retrolambda, Kotlin, Groovy
Slide 31
Slide 31 text
Check with Lambda
@Test
public void textIsCorrect() {
myTextView()
.check((View view, NoMatchingViewException e) ->
if (e != null) {
Assert.fail(e.getMessage());
}
Assert.assertEquals(
((TextView) view).getText().toString(),
"Hello, world"
);
})
}
Slide 32
Slide 32 text
But little dirty hack is needed with Kotlin...
private val activityRule = ActivityTestRule(MainActivity::class.java)
@Rule
public fun getActivityRule(): ActivityTestRule = activityRule
Slide 33
Slide 33 text
Page Object
Pattern?
Slide 34
Slide 34 text
Does Page Object Pattern adapt?
→ I think page object pattern is too huge
→ Espresso: Integration test
→ Selenium (Appium): End-to-end test
Slide 35
Slide 35 text
Conclusion
→ Espresso is high level wrapper of Instrumentation
→ There are many tips to make tests solid
→ Do not test everything using Espresso
Slide 36
Slide 36 text
→ Rocket Espresso Cellini V3 by Scott Schiller