Building a testing culture

Transcript

1. TESTING
   building
   CULTURE
   

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3. THIS IS NOT
   ABOUT TDD!
   

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4. @ordepdev
   

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5. First of all
   Why testing?
   

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6. “It’s time for software
   developers to take up the
   mantle of responsibility
   for what they produce.
   

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7. Testing is the
   engineering rigour of
   software development.
   

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8. Responsibility
   — the state or fact of being
   accountable or to blame for
   something.
   

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9. Rigour
   — the quality of being extremely
   thorough and careful.
   

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10. Software
    Engineering
    

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11. An engineering discipline
    that is concerned with
    all aspects of software
    production.
    

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12. MUCH MORE
    THAN CODING!
    

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13. Types of Bad
    Software Projects
    

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14. 1. Without tests.
    

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15. Zero Automated Tests.
    

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16. ZERO!
    

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17. Lack of
    professionalism?
    

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18. Lack of
    skills?
    

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19. Lack of
    knowledge?
    

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20. Lack of
    time to test?
    

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21. It can be all
    of them.
    

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22. What about
    software quality?
    

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23. Relax, they test
    all features with
    manual testing.
    

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25. 2. With Wrongly
    Designed Tests..
    

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26. Testing is
    HARD.
    

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28. Testing pitfalls:
    coupling.
    

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29. Implementation
    Boundary
    Testing
    Boundary
    

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30. Implementation
    Boundary
    Testing
    Boundary
    ✅
    ✅
    ✅
    ✅
    ✅ ✅
    ✅
    ✅
    ❌
    ❌
    

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31. Uncertainty
    and Doubt.
    

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32. Implementation
    Boundary
    Testing
    Boundary
    ✅
    ✅
    ✅
    ✅
    ✅
    ❌
    ❌
    ❌
    ❌
    ❌
    

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33. Testing pitfalls:
    performance.
    

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34. Taking
    too much time?
    — that’s a no run.
    

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35. Types of
    Testing
    

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36. 1. Testing after the
    implementation.
    

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37. 2. Testing during
    the implementation.
    

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38. 3. Testing that
    reproduce bugs.
    

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39. It’s our job to
    build a testing
    culture!
    

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40. But how?
    

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41. 5 rules.
    

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42. 1. Every change
    must have tests.
    

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43. 50
    100
    150
    200
    Development Unit Tests Functional Tests System Tests Production
    The cost of bugs
    

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44. Bugs in production
    are embarrassing
    and costly.
    

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45. 2. Write more
    than unit tests.
    

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46. Mutation
    testing!
    

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47. def add(x,y)
    x + y
    end
    def add(x,y)
    x - y
    end
    Source Code Mutation
    

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48. Property-based
    testing!
    

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49. http://blog.jessitron.com/2013/04/property-based-testing-what-is-it.html
    

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50. Contract
    testing!
    

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52. Model-based
    testing!
    

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53. Try formal
    methods!
    https://www.infoq.com/presentations/aws-testing-tla
    

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54. 3. Bug fixing
    must have tests.
    

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55. Don’t repeat the
    same bug hunting
    — write a test!
    

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56. 4. Testing code
    must be reviewed.
    

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57. A well-designed test
    suite is much easier to
    read, understand and
    evolve.
    

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58. Testing code is
    production code!
    

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59. 5. Test suites
    must be consistent.
    

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60. L12. assertEquals(input, expectation);
    L35. assertEquals(expectation, input);
    L43. assertThat(input).isEqualTo( expectation);
    Assertions
    

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61. L12. assertEquals(input, expectation);
    L35. assertEquals(expectation, input);
    L43. assertThat(input).isEqualTo( expectation);
    Assertions
    

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62. L12. createEntity
    L35. create_withValidPayload_success
    L43. create_withValidPayload_shouldPersistEntity
    Test Methods
    

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63. L12. createEntity
    L35. create_withValidPayload_success
    L43. create_withValidPayload_shouldPersistEntity
    Test Methods
    

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64. We must share
    the same values,
    practices, and tools.
    

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65. Enforce them through code
    reviews, static analysis, and
    style checking tools.
    

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66. Wrapping up.
    

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67. “People who are successful at
    automating tasks tend to work
    this way in every aspect of their
    jobs. It is just how they work; it
    is part of their culture.”
    

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68. Manual work
    is a bug.
    acmqueue | january-february 2018
    

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69. ALWAYS BE
    AUTOMATING!
    

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70. GO AND FIX YOUR
    BROKEN CULTURE!
    

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71. TESTING
    building
    CULTURE
    

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