The document discusses test-driven development (TDD) and the benefits of automated unit testing. It describes the TDD rhythm of adding a test, seeing it fail, making the minimal code change to pass the test, then refactoring. TDD helps produce maintainable, loosely coupled code by focusing on writing tests first, catching errors early, and communicating design decisions. The goals of TDD include making programming more enjoyable, understanding code easily, and reducing maintenance costs significantly.

1. Test Driven Development
Why Should You Care about TDD
And Automated (Unit) Testing?
Naresh Jain
Twitter: @nashjain
Blog: http://blogs.agilefaqs.com
Licensed Under Creative Commons by Naresh Jain
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2. Test Driven Development
TDD Rhythm - Test, Code, Refactor
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3. Test Driven Development
Add a Test
TDD Rhythm - Test, Code, Refactor
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4. Test Driven Development
Add a Test
Run the Test
TDD Rhythm - Test, Code, Refactor
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5. Test Driven Development
Add a Test
Pass
Run the Test
TDD Rhythm - Test, Code, Refactor
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6. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor
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7. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
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8. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Run the Test
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9. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
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10. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
Pass
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11. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
Pass
Refactor
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12. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
Pass
Refactor
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13. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
Pass
Refactor
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14. Test Driven Development
Add a Test
Pass
Run the Test
Fail
TDD Rhythm - Test, Code, Refactor Make a little
change
Fail
Run the Test
Pass
Refactor
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15. Why Learn TDD?
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16. Manual (monkey) Checking by
Developers and Tester
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17. Stay away from (time hungry)
debugger
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18. Maintain Focus
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19. Confidence
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20. Reduce Wastage: Hand Overs
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21. Helps you
Slow down
and Think
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22. Communication
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23. 11

24. Ultimate Goals
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25. Ultimate Goals
• Bring JOY back to programming
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26. Ultimate Goals
• Bring JOY back to programming
• Understand Code Easily
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27. Ultimate Goals
• Bring JOY back to programming
• Understand Code Easily
• Produce Simple, Testable, Loosely-Coupled Design
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28. Ultimate Goals
• Bring JOY back to programming
• Understand Code Easily
• Produce Simple, Testable, Loosely-Coupled Design
• Build Quality In
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29. Ultimate Goals
• Bring JOY back to programming
• Understand Code Easily
• Produce Simple, Testable, Loosely-Coupled Design
• Build Quality In
• Reduce Maintenance Significantly
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30. Living, up-to-date
specification
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31. Learning:
Listen to your code
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32. Testable Code by Design
+
Safety Net
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33. Communicate Design
Decisions
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34. Loosely-Coupled Design
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35. Refactoring
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36. Ultimate Goals
• Bring JOY back to programming
• Understand Code Easily
• Produce Simple, Testable, Loosely-Coupled Design
• Build Quality In
• Reduce Maintenance Significantly
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37. Thank You!
Naresh Jain
naresh@agilefaqs.com
Licensed Under Creative Commons by Naresh Jain
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