lessons from testing
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The document outlines lessons from testing examples, emphasizing that tests should be simpler, linear, and specific, while also noting that duplication often indicates missing abstractions. It discusses the relationship between code and tests, suggesting that they co-evolve and must complement each other. Key takeaways include the importance of clear diagnostics and the pitfalls of overusing mockist styles in testing.
lessons from testing
- 1. Lessons from Testing examples taken from http://cyber-dojo.org @JonJagger jon@jaggersoft.com 1 Thursday, 23 October 14
- 2. Avoid unnecessary burning of calories! 2 Thursday, 23 October 14
- 3. FizzBuzz 3 Thursday, 23 October 14
- 4. what do I notice? E09E8C snake 4 Thursday, 23 October 14
- 5. 5 Thursday, 23 October 14
- 6. Suppose we measure the average cyclomatic complexity of the code under test and the test code. 6 Thursday, 23 October 14
- 7. Higher number means more complex. 7 Thursday, 23 October 14
- 8. tests code 3.7 > 2.1 8 Thursday, 23 October 14
- 9. tests code 3.7 2.1 9 tests tests 4.3 > > Thursday, 23 October 14
- 10. NO!tests code 4.3> 3.7 > 2.1 10 tests tests Thursday, 23 October 14
- 11. tests code 2.1 == 2.1 11 Thursday, 23 October 14
- 12. NO! tests code 2.1 == 2.1 12 Thursday, 23 October 14
- 13. tests code 2.0 < 2.1 13 Thursday, 23 October 14
- 14. NO! tests code 2.0 < 2.1 14 Thursday, 23 October 14
- 15. code tests 1.0 <<< 2.1 15 Thursday, 23 October 14
- 16. YEScode tests 1.0 <<< 2.1 16 Thursday, 23 October 14
- 17. 1.0 ~> Simple E09E8C wolf 17 Thursday, 23 October 14
- 18. what do I notice most? 18 Thursday, 23 October 14
- 19. Duplication! 19 Thursday, 23 October 14
- 20. Duplication usually indicates a missing abstraction 20 Thursday, 23 October 14
- 21. what do I notice now? 21 Thursday, 23 October 14
- 22. Duplication! 22 Thursday, 23 October 14
- 23. 23 Thursday, 23 October 14
- 24. what do I notice now? 24 Thursday, 23 October 14
- 25. Duplication! 25 Thursday, 23 October 14
- 26. 26 Thursday, 23 October 14
- 27. what do I notice now? 27 Thursday, 23 October 14
- 28. missing examples? 28 Thursday, 23 October 14
- 29. 29 Thursday, 23 October 14
- 30. what do I notice now? 30 Thursday, 23 October 14
- 31. better test names? 31 Thursday, 23 October 14
- 32. 32 Thursday, 23 October 14
- 33. what do I notice now? 33 Thursday, 23 October 14
- 34. different_identifier_style? differentIdentifierStyle? 34 Thursday, 23 October 14
- 35. that's ok! 35 Thursday, 23 October 14
- 36. what do I notice now? 36 Thursday, 23 October 14
- 37. duplication? 37 Thursday, 23 October 14
- 38. this is worse! 38 Thursday, 23 October 14
- 39. how about this? 39 Thursday, 23 October 14
- 40. 40 Thursday, 23 October 14
- 41. 41 1.0 Specific ? 21F1F3 alligator Thursday, 23 October 14
- 42. 42 ! Thursday, 23 October 14
- 43. Specific ? 43 Thursday, 23 October 14
- 44. Specific :-) 44 Thursday, 23 October 14
- 45. Repetition ? 45 ? Thursday, 23 October 14
- 46. Repetition can indicate a missing abstraction 46 Thursday, 23 October 14
- 47. Specific 47 Thursday, 23 October 14
- 48. Specific 48 Thursday, 23 October 14
- 49. 49 Thursday, 23 October 14
- 50. Recently Used List 50 Thursday, 23 October 14
- 51. e.g. Recent Files... 51 Thursday, 23 October 14
- 52. what do I notice? DE3BF3 buffalo 52 Thursday, 23 October 14
- 53. Duplication! 53 Thursday, 23 October 14
- 54. What's left? red WTF? blue green 54 Thursday, 23 October 14
- 55. e.g. Files! 55 Thursday, 23 October 14
- 56. better! BAC947 snake 56 Thursday, 23 October 14
- 57. better still 57 Thursday, 23 October 14
- 58. What do I notice now? 58 Thursday, 23 October 14
- 59. Duplication! 59 Thursday, 23 October 14
- 60. What does assertEquals() print when it fails? 60 Thursday, 23 October 14
- 61. 61 Thursday, 23 October 14
- 62. Do your diagnostics diagnose? 62 Thursday, 23 October 14
- 63. What diagnostic do you want? 63 Thursday, 23 October 14
- 64. make it pass 64 refactor write a test for new functionality write a test for new functionality ship it! Thursday, 23 October 14
- 65. make it pass 65 write a test for new functionality write a test for new functionality refactor ship it! Thursday, 23 October 14
- 66. make it pass 66 refactor write a test for new functionality write a test for new functionality ship it! refactor the diagnostic! Thursday, 23 October 14
- 67. make it pass 67 refactor write a test for new functionality write a test for new functionality ship it! refactor the diagnostic! Thursday, 23 October 14
- 68. How about this? 68 Thursday, 23 October 14
- 69. Make it so! 69 Thursday, 23 October 14
- 70. 70 Thursday, 23 October 14
- 71. 71 A B C D E F G external external Thursday, 23 October 14
- 72. 72 A B C tA mockist style B' C' D E F G Thursday, 23 October 14
- 73. mockist style 73 A B C D E F G tB D' E' C' Thursday, 23 October 14
- 74. mockist style 74 A B C D E F G G' F' B' tC Thursday, 23 October 14
- 75. mockist style code tests 75 Thursday, 23 October 14
- 76. classic style 76 A B C tA D E F G D' F' Thursday, 23 October 14
- 77. classic style code tests 77 Thursday, 23 October 14
- 78. the.law.of.demeter 78 Thursday, 23 October 14
- 79. 79 Thursday, 23 October 14
- 80. which is more important? the code or the tests? 80 Thursday, 23 October 14
- 81. both 81 Thursday, 23 October 14
- 82. You cannot determine the character or nature of a system within itself. Attempts to do so lead to confusion and disorder. 82 Thursday, 23 October 14
- 83. code and tests co-evolve 83 Thursday, 23 October 14
- 84. evolution is always co-evolution 84 Thursday, 23 October 14
- 85. 85 Thursday, 23 October 14
- 86. 86 Thursday, 23 October 14
- 87. 87 testing time Thursday, 23 October 14
- 88. 88 debugging time Thursday, 23 October 14
- 89. debugging = removing what you don't want 89 Thursday, 23 October 14
- 90. if you get rid of what you don't want, will you be left with what you do want? 90 Thursday, 23 October 14
- 91. 91 ? Thursday, 23 October 14
- 92. 92 testing time Thursday, 23 October 14
- 93. 93 specification time Thursday, 23 October 14
- 94. 94 specific......... time Thursday, 23 October 14
- 95. Summary Burning calories - a metaphor for understandability Tests should be simple, linear, low complexity Tests should be specific Long_specific_test_names_are_ok Duplication usually means a missing abstraction Repetition can indicate a missing abstraction too Do your diagnostics diagnose? Custom assertions Don't cheat on test data - "String1" vs "red" Beware overusing Mockist style Code and tests co-evolve Test at the end is often debugging Test at the beginning as specification 95 Thursday, 23 October 14
- 96. 96 Thursday, 23 October 14
- 97. 97 Thursday, 23 October 14
- 98. 98 Thursday, 23 October 14
- 99. 99 Thursday, 23 October 14
- 100. code with no tests 100 FB75B3 Thursday, 23 October 14
- 101. 101 Thursday, 23 October 14
- 102. Lesson ONE test code must be much simpler than the code it tests 102 Thursday, 23 October 14