This document discusses Earl Grey, an open source UI testing framework for iOS apps created by Google. It describes how Earl Grey enables writing clear and concise UI tests by providing synchronization, user interactions like taps and swipes, and extensible APIs. The document outlines Earl Grey's selection, action and assertion APIs and provides examples of selecting elements and performing taps. It also mentions some of Earl Grey's other features like custom matchers and failure handlers.

1. UI TESTING WITH
EARL GREY
SHYAM BHAT
swift.berlin

2. TESTING MOBILE APPS

3. APPS ARE GETTING COMPLEX

4. TESTING IS ESSENTIAL FOR
GREAT QUALITY

5. TESTING INFLUENCES GOOD
ARCHITECTURE

6. TESTING IMPROVES CODE
READABILITY

7. PROGRAMS MUST BE WRITTEN FOR
PEOPLE TO READ, AND ONLY
INCIDENTALLY FOR MACHINES TO
EXECUTE.
Harold Abelson

8. UI TESTS ARE ESSENTIAL

9. ▸ Germany’s leading digital
real estate marketplace.
▸ Over 12 million App
downloads.
▸ Swift + Objective C

10. OUR TEST SUITE
▸ XCTest + FBSnapshots for Unit testing
▸ Xcode UI Testing + KIF
▸ 3000+ Unit tests and Integration tests.

11. BUT…

12. UI TESTS ARE SLOW AND
COMPLEX TO WRITE

13. SYNCHRONIZING THE UI IS A
PAIN

14. RESULTS ARE INCONSISTENT
AND UNRELIABLE

16. MEET EARL GREY

17. EARL GREY IS AN UI AUTOMATION
TEST FRAMEWORK THAT ENABLES
YOU TO WRITE CLEAR, CONCISE
TESTS.

18. EARL GREY
▸ Google’s internal UI Testing framework.
▸ Used in YouTube, Google Calendar, Google Photos,
Google Translate, Google Play Music.
▸ Recently open sourced.

19. FEATURES
▸ Synchronization.
▸ User-like interactions (taps, swipes).
▸ Visibility checks before interactions.
▸ Extensible API - custom UI actions and assertions.

20. HOW EARL GREY WORKS
▸ EarlGrey runs in the same process as the app under test,
and has access to the same memory as the app.
▸ Uses private methods to learn view hierarchy and inject
touches.
▸ Works in conjunction with the XCTest framework.

21. EARL GREY API
▸ Interaction APIs
▸ Synchronization APIs
▸ Other Top Level APIs

22. INTERACTION APIS
▸ Selection API - Selecting an element to interact with.
▸ Action API - Performing an action on it,
▸ Assertion API - Making an assertion to verify state and
behavior.

23. SELECTION
▸ Format:
selectElementWithMatcher(<GREYMatcher>)
▸ GREYMatcher
grey_accessibilityID(“ClickMe”)
grey_accessibilityLabel(“Berlin")
grey_kindOfClass(UITableViewCell)
▸ Example:
// Select the button with Accessibility ID "clickMe".
EarlGrey().selectElementWithMatcher(grey_accessibilityID("ClickMe"))

24. SELECTION
▸ A GREYMatcher compliant object can be ambiguous and match
multiple elements.
▸ Must be narrowed down until a single element is identified.
▸ You can combine multiple GREYMatchers using -
grey_allOf()
grey_anyOf()
grey_not()
▸ Example:
let sendButtonMatcher : <GREYMatcher> =
grey_allOf(grey_accessibilityLabel("Send"), grey_sufficientlyVisible(), nil)
EarlGrey().selectElementWithMatcher(sendButtonMatcher)

25. ACTION
▸ Format:
selectElementWithMatcher(<GREYMatcher>).performAction(<GREYAction>)
▸ <GREYAction>
grey_tap()
grey_longPress()
grey_tapAtPoint(CGPoint point)
grey_scrollInDirection(GREYDirection direction, CGFloat amount)
▸ Example:
// Select the button with Accessibility ID “clickMe" and perform Tap Action.
EarlGrey().selectElementWithMatcher(grey_accessibilityID(“ClickMe”)).
performAction(grey_tap())

26. ASSERTIONS
▸ Format:
selectElementWithMatcher(<GREYMatcher>).assertWithMatcher(<GREYAction>)
▸ Example:
// Select the button with Accessibility ID “ClickMe" and perform Tap Action.
EarlGrey().selectElementWithMatcher(grey_accessibilityID(“ClickMe”))
.assertWithMatcher(grey_sufficientlyVisible())

27. SEARCH FUNNEL TESTS
DEMO :

28. OTHER API
▸ Custom Assertions and Matchers
▸ Failure Handlers
▸ Synchronization API
▸ Layout Testing

29. KNOWN ISSUES
▸ Cannot interact with system dialogs (yet).
▸ No 3D Touch support.

30. REFERENCES
▸ Github Repository and API Documentation - https://
github.com/google/EarlGrey
▸ Google’s Developer blog - https://
developers.googleblog.com/2016/02/earlgrey-ios-
functional-ui-testing.html

31. THANKS!
QUESTIONS?
@bhatthead
github.com/shyambhat