Love your tests

Testing practices and principles used at .Tuenti in order to get better tests and make them easier to write and read.

Transcript

1. Love your tests @KINISOFTWARE MADRID · NOV 27-28 · 2015
2. .Love your tests (Story of a healthy addiction - Chapter 2) kinisoftware kini@tuenti.com
5. We are hiring!!
6. Once upon a time… 2013 1
7. .Tuenti <3 .Testing (Story of a healthy addiction - Chapter 1)
8. • We <3 our customers • Confidence • Safety Net • Refactoring, refactoring, refactoring • It is professional, guys :)
9. By Martin Fowler
10. Testability
11. Present day… 2
12. Good good
13. “It’s overwhelmingly easy to write bad unit tests that add very little value to a project while inflating the cost of code changes astronomically.”
14. • Code coverage != Test quality • Don’t Repeat Yourself (Globally) • Mocks, mocks everywhere • Test smells
15. .Tuenti Subject Under Test 3
16. Microservices Fresh start Java Focus on testability
17. Talk is cheap. Show me the code.
18. Coding time (1446 tests) •Code readability + Naming + Code structure + DSL • One (logical) assert per test + Meaningful asserts + Custom matchers • Exceptions • Builders + Mothers • Mock providers • Testing real things • Customize your runners + DI
19. Code readability + Naming + Code structure + DSL • Unit & Integration folders • Tests names • AAA • @SetUp vs Explicit SetUpTM • DSL
20. • Unit & Integration folders
24. Code readability + Naming + Code structure + DSL • Tests names
26. Code readability + Naming + Code structure + DSL • AAA
28. Code readability + Naming + Code structure + DSL • @SetUp vs Explicit SetUpTM
29. Code readability + Naming + Code structure + DSL
30. Code readability + Naming + Code structure + DSL • DSL
32. One (logical) assert per test + Meaningful asserts + Custom matchers • Assert Equals vs Assert That • Actual & Expected • One (logical) assert per test • Hamcrest & Assert J • Custom matchers
33. • Assert Equals vs Assert That / Actual & Expected One (logical) assert per test + Meaningful asserts + Custom matchers
34. One (logical) assert per test + Meaningful asserts + Custom matchers • One (logical) assert per test
37. One (logical) assert per test + Meaningful asserts + Custom matchers • Hamcrest
38. • Assert J
39. One (logical) assert per test + Meaningful asserts + Custom matchers • Custom matchers
41. Exceptions • Try/Catch… really? • @Test(expected = ….) • @Rule ExpectedException
42. Exceptions • @Test(expected = ….) • @Rule ExpectedException
43. Builders + Mothers • Value Objects are leaf in our classes tree == No mocks here please • Building value objects “issue” • Builders • Mothers • Builders + Mothers
44. Builders + Mothers • Builders
45. Builders + Mothers
46. Mock providers • DRY using mocks globally • DSL • Builders + Mocks = Mocks providers
48. Testing using real things • Mocks, mocks everywhere • Sociable Unit Tests • Local resources • Helper & Utility classes
52. Testing using real things • Helper & Utility classes
53. Customize your runners + DI • JUnit @RunWith + your platform • SetUp and TearDown for expensive resources • DI container and “integration mocks”
54. Customize your runners + DI • JUnit @RunWith + your platform
56. Customize your runners + DI • SetUp and TearDown for expensive resources
57. Customize your runners + DI • SetUp and TearDown for expensive resources
58. Customize your runners + DI
59. .Thanks!
61. • Mix JVM Languages (Groovy&Scala rule!) • Java 8 fuck yeah! • JUnit Lambda • Property-based testing • Mutation Testing Keep an eye on…
62. Reading a lot • Effective Unit Testing • WEWUT • Pragmatic Unit Testing with JUnit • GOOS • The Art of Unit Testing • JUnit in Action • xUnit Patterns • Refactoring