Score the Tendulkar Test Coverage

Simple coding principles and design patterns you can follow to make your code testable and achieve organic and high test coverage

Transcript

1. Score the Tendulkar Test Coverage @GopalAkshintala
2. Gopal S Akshintala Engineering Lead, Salesforce Community Day 2022 September 10th, 2022 T-Hub, Hyderabad @GopalAkshintala overfullstack.ga
3. Sachin Tendulkar holds the record for highest number of dismissals in the 90s (28 times)🏏
4. @GopalAkshintala
5. Why Unit Test ? 🧪 @GopalAkshintala
6. Why Unit Test? @GopalAkshintala Find Bugs Statement Coverage Behaviour documentation in form of code Strive for behaviour coverage NOT Statement coverage
7. What makes Unit Testing Di ffi cult? 😓 @GopalAkshintala Code Smells void methods static methods that are not static Bad Design Legacy Code interactions
8. We have the Hammer! OOps! @GopalAkshintala
9. The Unstoppable Hammer! OOps! @GopalAkshintala Suppress this and super constructor static init blocks Stub private methods static methods final methods Constructors Mock final classes
10. The PowerMock Rocky! @GopalAkshintala OOps! 100%
11. The Dark Powers 👹 Synthetic coverage is dangerous PowerMock is a new framework to learn Involves a lot of Setup and trail-and-error to get it right Tests written with PowerMock are brittle and difficult to Maintain It’s not Transparent OOps! @GopalAkshintala
12. @GopalAkshintala
13. PowerMock is a 💊 Painkiller @GopalAkshintala
14. But! Why is PowerMock Invasive? @GopalAkshintala
15. @GopalAkshintala powermock.github.io
16. PowerMock Compatibility Incompatible with JUnit 5 JUnit 5 was release 5 years ago Incompatible with Latest Mockito Latest Mockito: 4.20 Compatible version: 3.12 Not fully compatible with Java 11 OOps! @GopalAkshintala
17. But do I need Unit Tests at all? Can’t I get Coverage with Integration Tests!? 🤷 @GopalAkshintala
18. @GopalAkshintala ITests Vs UTests
19. @GopalAkshintala Use-Case Diagram
20. @GopalAkshintala ITests Vs UTests Use-case: How customer uses ITests should test Features Use-cases : Features : Components 1 Feature: Reflects software Functionality UTests should test Component Behaviour N N
21. @GopalAkshintala ITests Vs UTests Traceability - How well a given test can precisely trace/pinpoint the cause of failure when it fails Productivity - Writing, Executing and Maintaining effort
22. The Redemption 🍕 🥗 @GopalAkshintala
23. @GopalAkshintala Code Smells 🐽
24. @GopalAkshintala Code Smells 🐽 Avoid void Methods
25. @GopalAkshintala Code Smells 🐽 Are static methods bad for Unit testing?
26. @GopalAkshintala Pure Vs Impure Pure Logic Impure Side-Effects REST I/O DB I/O Events • Data-in 
 Data-out • Referentially Transparent
27. @GopalAkshintala Impure static void add(int a, int b) { System.out.println(a + b); }
28. @GopalAkshintala Pure static int add(int a, int b) { return a + b; }
29. @GopalAkshintala Impure Pure static void add(int a, int b, Consumer<Integer> consumer) { consumer.accept(a + b); } / / Function call in Prod add(1, 2, System.out :: println); / / Function call in Test add(1, 2, result -> assertEquals(3, result));
30. @GopalAkshintala Bad Design
31. @GopalAkshintala Bad Design OOP P 💩
32. @GopalAkshintala 👨💼 🙉 Domain Logic DB layer Prod Test
33. @GopalAkshintala Design for Tests A Unit Test is the First client for your Component
34. @GopalAkshintala Test in Isolation Mock Dependencies NOT Statements
35. @GopalAkshintala Test in Isolation Inject your Dependencies 💉
36. @GopalAkshintala Legacy Dependencies 🗿 🗿
37. @GopalAkshintala Legacy Dependencies If you interact with a
 Legacy component, Your component Instantly turns Legacy!
38. @GopalAkshintala Legacy Dependencies If you “Directly” interact with a
 Legacy component, Your component Instantly turns Legacy!
39. @GopalAkshintala Ports & Adapters Domain Adapters
40. @GopalAkshintala 👨💼 🙉 Domain Logic DB layer Prod Test
41. @GopalAkshintala Port 👨💼 🐵 Isolated Domain Logic DB layer Prod Adapter Fake Adapter Prod Test
42. @GopalAkshintala Black box Unit Testing Unit Test ! = Test Internals Unit Test == E2E test for the Component
43. @GopalAkshintala Anti-Patterns (digitaltapestry.net) https://confluence.internal.salesforce.com/display/TESTSFDC/ Unit+Testing+Best+Practices https://confluence.internal.salesforce.com/display/TESTSFDC/ Unit+Test+Recipes%3A+How+to+Write+High-Quality+Tests Explanation how proxy based Mock Frameworks work Write tests. Not too many. Mostly integration. (kentcdodds.com) Testing of Microservices - Spotify Engineering : Spotify Engineering (atspotify.com) On the Diverse And Fantastical Shapes of Testing (martinfowler.com) ongoing by Tim Bray · Testing in the Twenties (tbray.org) Resources
44. No one gives you Change, you need to bring Change - Ramulu, Bus conductor #dadJoke
45. @GopalAkshintala github.com/overfullstack/sttc-demo { } speakerdeck.com/gopalakshintala/ score-the-tendulkar-test-coverage
46. @GopalAkshintala 🐵