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Mocks and Stubs and Spies, oh my!

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Avatar for Brian Gardner Brian Gardner
August 27, 2018
Technology
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Mocks and Stubs and Spies, oh my!

Slides from my introduction to test doubles talk given at DroidCon NYC

Avatar for Brian Gardner

Brian Gardner

August 27, 2018

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Transcript

  1. Mocks and Stubs and Spies, Oh My! Brian Gardner

  2. Test Double Hierarchy Test Doubles Mock Fake Spy Stub Dummy

  3. Types of Tests

  4. When to use Test Doubles? • System under test has

    indirect inputs • System under test has indirect outputs • Slow tests*

  5. Indirect Inputs

  6. Indirect Outputs

  7. Slow Tests

  8. Mocks

  9. What is a Mock?

  10. What is a Mock?

  11. What is a Mock?

  12. Mock Types Mocks Strict Lenient

  13. Mock Usage

  14. Mock Usage

  15. Mock Usage

  16. Mock Usage

  17. Stubs

  18. What is a Stub?

  19. What is a Stub?

  20. What is a Stub?

  21. Stub Types Stubs Responder Saboteur Temporary

  22. Stub Usage

  23. Stub Usage

  24. Stub Usage

  25. Stub Usage

  26. Spies

  27. What is a Spy?

  28. Spy Usage

  29. Spy Usage

  30. Spy Usage

  31. Spy Usage

  32. Dummies

  33. What is a Dummy?

  34. What is a Dummy?

  35. Dummy Usage

  36. Dummy Usage

  37. Dummy Usage

  38. Dummy Usage

  39. Fakes

  40. What is a Fake?

  41. Fake Usage

  42. Fake Usage

  43. Fake Usage

  44. Fake Usage

  45. Term Confusion

  46. Mocking Library

  47. Mockito mocks

  48. Mockito Stubs

  49. Mockito Spies

  50. Actual Mockito Spies

  51. Mockito dummies

  52. Mockito Fakes N/A

  53. Recap • Use correct terms for more effective communication •

    Match test doubles to the appropriate tests • Don’t over use them

  54. Who am I? Brian Gardner @BrianGardnerAtl