Berlindroid: Kotlin Test Robots

Following the announcement at this year's Google IO we've seen a dramatic uptake in Kotlin and over the last few months we've learnt how we can use it to improve and produce clean architecture applications and supercharge our unit tests, but what about our UI tests?

In this session, I'll show you how you can utilise Kotlin with the Robot pattern to build concise, terse and easy to read UI tests

Transcript

1. Kotlin Test Robots
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2. Testing
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3. Tooling
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4. ashdavies.io
   

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5. UI Testing
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6. Architecture Agnostic
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7. Espresso
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8. ashdavies.io
   

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9. ViewInteraction appCompatEditText = onView(
   allOf(withId(R.id.email),
   withParent(allOf(withId(R.id.activity_main),
   withParent(withId(android.R.id.content)))),
   isDisplayed()));
   appCompatEditText.perform(click());
   ViewInteraction appCompatEditText2 = onView(
   allOf(withId(R.id.email),
   withParent(allOf(withId(R.id.activity_main),
   withParent(withId(android.R.id.content)))),
   isDisplayed()));
   appCompatEditText2.perform(replaceText("test@invalid"), closeSoftKeyboard());
   ViewInteraction appCompatButton = onView(
   allOf(withId(R.id.validate_button), withText("Validate"),
   withParent(allOf(withId(R.id.activity_main),
   withParent(withId(android.R.id.content)))),
   isDisplayed()));
   appCompatButton.perform(click());
   ViewInteraction textView = onView(
   allOf(withId(R.id.validation_result), withText("Invalid Email Format"),
   childAtPosition(
   allOf(withId(R.id.activity_main),
   childAtPosition(
   withId(android.R.id.content),
   0)),
   1),
   isDisplayed()));
   textView.check(matches(isDisplayed()));
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10. "I've calculated your chance of survival,
    but I don't think you'll like it."
    -- Marvin
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11. Espresso
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12. Espresso
    @Test
    fun shouldValidateEmailAddress() {
    onView(withId(R.id.email)).check(matches(isDisplayed()))
    onView(withId(R.id.email)).perform(typeText("ash"))
    onView(withId(R.id.login)).perform(click())
    onView(withId(R.id.error)).check(matches(allOf(isDisplayed(), withText(R.string.invalid_email))))
    }
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13. Espresso
    @Test
    fun `should validate email address`() {
    onView(withId(R.id.email)).check(matches(isDisplayed()))
    onView(withId(R.id.email)).perform(typeText("ash"))
    onView(withId(R.id.login)).perform(click())
    onView(withId(R.id.error)).check(matches(allOf(isDisplayed(), withText(R.string.invalid_email))))
    }
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14. ashdavies.io
    

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15. Robots
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16. ashdavies.io
    

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17. Robots
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18. Robots
    — Structure your own domain language
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19. Robots
    — Structure your own domain language
    — Contextualise assertions and verifications
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20. Robots
    — Structure your own domain language
    — Contextualise assertions and verifications
    — High level intention language
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21. Robots
    — Structure your own domain language
    — Contextualise assertions and verifications
    — High level intention language
    — Reads like a script
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22. Sound Familiar?
    Testing Robots (Kotlin Night) - JW
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23. ashdavies.io
    

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24. ashdavies.io
    

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25. Robot
    class FinanceRobot {
    fun price(amount: Int): FinanceRobot { ... }
    fun costs(amount: Int): FinanceRobot { ... }
    fun funds(amount: Int): FinanceRobot { ... }
    fun next(): ResultRobot { ... }
    }
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26. Robots
    class FinanceRobot {
    fun price(amount: Int) = apply {
    onChild(withId(R.id.price)).perform(typeText(value))
    }
    fun costs(amount: Int) = apply {
    onChild(withId(R.id.costs)).perform(typeText(value))
    }
    fun funds(amount: Int) = apply {
    onChild(withId(R.id.funds)).perform(typeText(value))
    }
    fun next() = apply {
    onChild(withId(R.id.next)).perform(click())
    }
    }
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27. class FinanceTest {
    fun `should update seek bar amount`() {
    FinanceRobot()
    .price(200_000)
    .next()
    }
    }
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28. Cucumber
    Gherkin
    Feature: Some terse yet descriptive text of what is desired
    Textual description of the business value of this feature
    Business rules that govern the scope of the feature
    Any additional information that will make the feature easier to understand
    Scenario: Some determinable business situation
    Given some precondition
    And some other precondition
    When some action by the actor
    And some other action
    And yet another action
    Then some testable outcome is achieved
    And something else we can check happens too
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29. Kotlin
    @Test
    fun `should update progress bar amount`() {
    FinanceRobot()
    .given { amount(200_000) }
    .then { progress(200_000) }
    }
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30. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun amount(value: Int) = apply {
    onChild(withId(R.id.input)).perform(typeText(value))
    }
    }
    }
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31. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun amount(value: Int) = apply {
    onChild(withId(R.id.input)).perform(typeText(value))
    }
    }
    }
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32. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun amount(value: Int) = apply {
    onChild(withId(R.id.input)).perform(typeText(value))
    }
    }
    }
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33. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun amount(value: Int) = apply {
    onChild(withId(R.id.input)).perform(typeText(value))
    }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    }
    }
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34. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun inputText(value: Int) = apply {
    onChild(withId(R.id.input)).perform(typeText(value))
    }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    }
    class Then {
    fun hasProgress(value: Int) = apply {
    onChild(withId(R.id.progress)).perform(scrubProgress(value))
    }
    }
    }
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35. IntentsTestRule
    @get:Rule
    val rule: IntentsTestRule = FinanceRobot.rule(FinanceActivity::class.java, false, false)
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36. Robot Companion
    class FinanceRobot {
    companion object {
    fun start(rule: IntentsTestRule, amount: Int = 200_000): FinanceRobot {
    rule.launchActivity(FinanceActivity.newIntent(context, amount))
    return FinanceRobot()
    }
    }
    }
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37. Testing Robots
    @Test
    fun `should update progress bar amount`() {
    FinanceRobot.start(rule)
    given { inputText("200000") }
    then { hasProgress(200_000) }
    }
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38. Testing Robots
    @Test
    fun `should update progress bar amount`() {
    FinanceRobot.start(rule)
    given { /* ??? */ }
    then { /* ??? */ }
    }
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39. Kotlin
    class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun inputText(value: Int) = apply { /* ... */ }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    }
    class Then {
    fun hasProgress(value: Int) = apply { /* ... */ }
    }
    }
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40. class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun price(func: Will.() -> Unit) = Will(R.id.price).apply(func)
    class Will(@IdRes parent: Int) {
    fun inputText(value: Int) = apply { /* ... */ }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    }
    }
    class Then {
    fun hasProgress(value: Int) = apply { /* ... */ }
    }
    }
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41. class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun price(func: Will.() -> Unit) = Will(R.id.price).apply(func)
    class Will(@IdRes parent: Int) {
    fun inputText(value: Int) = apply {
    onView(allOf(isDescendantOfA(withId(parent)), withId(R.id.input)))
    .perform(typeText(value)).perform(pressImeActionButton())
    }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    }
    }
    class Then {
    fun hasProgress(value: Int) = apply { /* ... */ }
    }
    }
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42. class FinanceRobot {
    fun given(func: Given.() -> Unit) = Given().apply(func)
    class Given {
    fun price(func: Will.() -> Unit) = {
    Will(R.id.price).apply(func)
    return FinanceRobot()
    }
    class Will(@IdRes parent: Int) {
    fun inputText(value: Int) = apply { /* ... */ }
    }
    }
    fun then(func: Then.() -> Unit) = Then().apply(func)
    class Then {
    fun hasProgress(value: Int) = apply { /* ... */ }
    }
    }
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43. Testing Robots
    fun `should update progress bar amount`() {
    FinanceRobot.start(rule)
    given {
    price { inputText("200000") }
    funds { scrubTo(40_000) }
    }
    then {
    price { hasText("200.000 €") }
    funds { hasText("40.000 € / 20 %") }
    }
    }
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44. Testing Robots
    fun `should update progress bar amount`() {
    rule.start()
    given {
    price { inputText("200000") }
    funds { scrubTo(40_000) }
    }
    then {
    price { hasText("200.000 €") }
    funds { hasText("40.000 € / 20 %") }
    }
    }
    fun IntentsTestRule.start(amount: Int = 200_000): FinanceRobot {
    return FinanceRobot.start(this, amount)
    }
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45. Thanks
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