TESTING IT & LOVING IT ZAN MARKAN 

THE WHAT AGENDA ▸ Motivation ▸ Testing 101 ▸ How do I… ▸ ♥ It 

MOTIVATION - 2 REASONS REASON[0] 

MOTIVATION - 2 REASONS REASON[1] “MOVE FAST AND BREAK THINGS” - a company at scale “MOVE FAST AND KNOW WHEN THINGS BREAK” - me 

MOTIVATION - 2 REASONS java.lang.ArrayIndexOutOfBoundsException: 2 

TESTING 101 WHAT IS THIS “TESTING” THING? 

TESTING 101 WHAT IS THIS “TESTING” THING ▸ You are doing it already ▸ Just get the computer to do it, and call it “automated”! ▸ Hint, it’s not just for QA ▸ …and it takes many shapes & forms 

TESTING 101 ANATOMY OF A TEST ▸ System under test ▸ Preconditions ▸ Input ▸ Expected output 

TESTING 101 WHY TEST? ▸ FREE documentation ▸ More FREE Time ▸ FREE architecture (to some extent) ▸ For love of money… 

TESTING 101 WHAT TO TEST ▸ Frontend vs Backend code ▸ Config changes ▸ What happens when you time travel… ▸ Remember when the API developer tried to murder you? ▸ 

TESTING 101 THE MANDATORY PYRAMID OF TESTS Source: Google Testing blog http://googletesting.blogspot.nl/2015/04/just-say-no-to-more-end-to-end-tests.html 

HOW DO I…? TALES FROM THE TRENCHES 

HOW DO I… UNIT TESTING ▸ Fast and simple ▸ Test the public “API” on a class level ▸ If it’s hard, you’re doing it wrong ▸ Having fun with mocks ▸ Great for TDD 

HOW DO I… UNIT TESTING BEST PRACTICES ▸ BFFs: POJOs, Mocks and Interfaces ▸ No statics and com.android.* allowed ▸ Wrap it! 

HOW DO I… TEST DRIVEN WHAT?? ▸ Not just for purists ▸ Red - Green - Refactor ▸ Drives design ▸ Free code coverage ▸ Learn by doing Katas 

HOW DO I… …IN THE LAND OF MVP ▸ Model - View - Presenter pattern ▸ The most popular Android architecture at present ▸ (after spaghetti code) ▸ Easily testable 

HOW DO I… MVP - MODEL ▸ Pure Java ▸ Unit tests - jUnit, Mockito ▸ Business logic ▸ Easiest to test 

HOW DO I… MVP - PRESENTER ▸ Still pure Java (ideally) ▸ (Fairly) clean architecture ▸ Lots of interfaces, piping… 

HOW DO I… MVP - VIEW ▸ Tied with framework :( ▸ No pure java testing, apart from Robolectric ▸ Espresso, Android Instrumentation, Calabash… ▸ Integration testing? 

HOW DO I… ROBOLECTRIC ▸ TDD on the views ▸ Katas - http://coreylatislaw.com/robolectric-kata/ ▸ Shadow classes != Android framework ▸ So simple, it’s dangerous 

HOW DO I… INSTRUMENTATION FRAMEWORK ▸ Runs on “proper” Android ▸ Espresso for fluent testing experience ▸ Test individual screens / activities /services/ applications ▸ Test flow between them ▸ Config changes much? 

HOW DO I… MORE TESTING SHENANIGANS ▸ Functional/End 2 End ▸ BDD-ish ▸ Calabash, Robotium, Appium and other -iums. ▸ Device clouds ▸ Can take forever 

HOW DO I… RXJAVA (WE’VE ALL HEARD ABOUT THAT) ▸ Easy to test functions individually ▸ Mocking functions ▸ Observable.toBlocking() ▸ TestScheduler 

…AND LOVING IT OTHER FUN STUFF 

LOVING IT TESTING PLAYGROUND ▸ They never see production, yet are still there ▸ New coding styles (drop hungarian notation, perhaps?) ▸ Architectural patterns ▸ Try new libraries with androidTestCompile and testCompile 

LOVING IT A NICE TIME TO TRY KOTLIN Source: Antonio Leiva - Kotlin for Android Developers http://antonioleiva.com/kotlin-android-developers-book/ 

FIN GET IN TOUCH ▸ Twitter: @zmarkan ▸ Slack https://androidchat.co/ @zmarkan ▸ Reddit /r/androiddev /u/zmarkan ▸ www.spacecowboyrocketcompany.com ▸ [email protected] 

DIRECTOR’S CUT (RE)SOURCES ▸ http://globalday.coderetreat.org/ ▸ https://google.github.io/android-testing-support-library/ ▸ http://calaba.sh/ ▸ https://aws.amazon.com/device-farm/ ▸ https://medium.com/ribot-labs/unit-testing-rxjava-6e9540d4a329 ▸ http://fedepaol.github.io/blog/2015/09/13/testing-rxjava-observables-subscriptions/ ▸ http://reactivex.io/RxJava/javadoc/ ▸ https://kotlinlang.org/docs/tutorials/koans.html