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
   

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2. .Love your tests
   (Story of a healthy addiction - Chapter 2)
   kinisoftware kini@tuenti.com
   

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5. We are
   hiring!!
   

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6. Once upon a time…
   2013
   1
   

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7. .Tuenti <3 .Testing
   (Story of a healthy addiction - Chapter 1)
   

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8. • We <3 our customers
   • Confidence
   • Safety Net
   • Refactoring, refactoring, refactoring
   • It is professional, guys :)
   

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9. By
   Martin Fowler
   

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10. Testability
    

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11. Present day…
    2
    

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12. Good
    good
    

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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.”
    

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14. • Code coverage != Test quality
    • Don’t Repeat Yourself (Globally)
    • Mocks, mocks everywhere
    • Test smells
    

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15. .Tuenti
    Subject Under Test
    3
    

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16. Microservices
    Fresh start
    Java
    Focus on testability
    

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17. Talk is cheap.
    Show me the code.
    

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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
    

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19. Code readability + Naming + Code
    structure + DSL
    • Unit & Integration folders
    • Tests names
    • AAA
    • @SetUp vs Explicit SetUpTM
    • DSL
    

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20. • Unit & Integration folders
    

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24. Code readability + Naming + Code
    structure + DSL
    • Tests names
    

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26. Code readability + Naming + Code
    structure + DSL
    • AAA
    

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28. Code readability + Naming + Code
    structure + DSL
    • @SetUp vs Explicit SetUpTM
    

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29. Code readability + Naming + Code
    structure + DSL
    

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30. Code readability + Naming + Code
    structure + DSL
    • DSL
    

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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
    

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33. • Assert Equals vs Assert That / Actual & Expected
    One (logical) assert per test +
    Meaningful asserts + Custom matchers
    

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34. One (logical) assert per test +
    Meaningful asserts + Custom matchers
    • One (logical) assert per test
    

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37. One (logical) assert per test +
    Meaningful asserts + Custom matchers
    • Hamcrest
    

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38. • Assert J
    

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39. One (logical) assert per test +
    Meaningful asserts + Custom matchers
    • Custom matchers
    

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41. Exceptions
    • Try/Catch… really?
    • @Test(expected = ….)
    • @Rule ExpectedException
    

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42. Exceptions
    • @Test(expected = ….)
    • @Rule ExpectedException
    

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43. Builders + Mothers
    • Value Objects are leaf in our classes tree == No mocks here please
    • Building value objects “issue”
    • Builders
    • Mothers
    • Builders + Mothers
    

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44. Builders + Mothers
    • Builders
    

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45. Builders + Mothers
    

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46. Mock providers
    • DRY using mocks globally
    • DSL
    • Builders + Mocks = Mocks providers
    

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48. Testing using real things
    • Mocks, mocks everywhere
    • Sociable Unit Tests
    • Local resources
    • Helper & Utility classes
    

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52. Testing using real things
    • Helper & Utility classes
    

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53. Customize your runners + DI
    • JUnit @RunWith + your platform
    • SetUp and TearDown for expensive resources
    • DI container and “integration mocks”
    

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54. Customize your runners + DI
    • JUnit @RunWith + your platform
    

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56. Customize your runners + DI
    • SetUp and TearDown for expensive resources
    

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57. Customize your runners + DI
    • SetUp and TearDown for expensive resources
    

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58. Customize your runners + DI
    

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59. .Thanks!
    

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61. • Mix JVM Languages (Groovy&Scala rule!)
    • Java 8 fuck yeah!
    • JUnit Lambda
    • Property-based testing
    • Mutation Testing
    Keep an eye on…
    

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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
    

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