Intro To TDD

A short session introducing Test Driven Development presented at Evergreen State University in Olympia, Washington.

Transcript

1. Intro to Test Driven
   Development
   

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2. Jim Holmes
   Executive Consultant, Guidepost Systems LLC
   Jim@GuidepostSystems.com
   GitHub: JimHolmes
   Xbox: FrazzledDad
   Blogs:
   http://GuidepostSystems.com
   http://FrazzledDad.com
   Coding for Non-Coders: Lesson 1—Course Introduction
   Who am I?
   

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3. Slides:
   https://speakerdeck.com/
   jimholmes/intro-to-tdd
   

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4. How do you know
   your stuff works?
   

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5. How do you know
   you built
   the right thing?
   

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6. How do you keep
   your stuff working?
   

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7. Goals for today:
   Talk about building test cases
   Spend some writing tests and code
   

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8. Level Set:
   What are all y’all working
   with?
   (testing, specs, etc.)
   

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9. Why writing tests matters
   

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10. Correctness
    

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11. Maintainability
    

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12. Why writing tests
    first
    matters
    

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13. Stay lean
    

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14. Focus on value
    

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15. Red
    Refactor Green
    

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16. Think
    Refactor
    Green
    Red
    

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17. The problem
    

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18. Customer wants a
    payroll system
    

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19. Today’s work:
    Figure payroll for hourly
    workers
    

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20. Let’s write some specs!
    

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21. Hours
    Worked
    Hourly Rate Wages Should Be
    0 10 0
    1 10 10
    40 10 400
    41 10 415
    60 10 700
    61 10 Error. Requires supervisor review (Business rule!)
    -1 10 Error. Do not process
    1 -1 Error. Do not process
    10 Max Value
    (500)
    10 * max value.
    10 Max Value + 1 Error. Requires supervisor review (Business rule!)
    10 1 10
    

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22. Let’s write some tests!
    

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