TCR workshop

Slides of the workshop co-facilitated in Stockholm https://www.meetup.com/es-ES/Stockholm-Software-Craftsmanship/events/259388924

The goal was to get to know the TCR workflow, try it in a couple of katas and learn something new, whatever it is :-)

Transcript

1. TCR workshop
   "test && commit || revert"
   Stockholm, 12th March 2019
   

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2. Ego slide
   Software professional (code, product, people...)
   @islomar
   islomar@gmail.com
   Something
   @joebew42
   joebew42@gmail.com
   

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3. Agenda
   1. Review of TDD
   2. New workflow: TCR (test && commit || revert)
   3. Presentation of the kata: Fibonacci
   4. First round to try… go!!
   5. Second round to try… go!!
   6. Opinions and feedback
   7. Some downsides of TCR
   8. Final recap
   9. Interesting links
   10. Dinner and networking!
   

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4. Disclaimer
   We have not tried TCR with Production code
   We are learners
   We are here to practice and learn the new workflow
   

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5. Review TDD
   http://luizricardo.org/wordpress/wp-content/upload-files/2014/05/tdd_flow.gif
   

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6. A new workflow: TCR
   Popularised by Kent Beck after post in September 2018:
   https://medium.com/@kentbeck_7670/test-commit-revert-870bbd756864
   Experiment in Code Camp by Oddmund Strømmer, Lars Barlindhaug and Ole
   Johannessen
   Basic idea: test && commit || revert
   

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7. TCR: an oversimplified diagram
   Run your
   tests…result?
   commit
   revert
   write your code
   GREEN
   RED
   

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8. https://rachelcarmena.github.io/img/cards/posts/test-driven-programming-workflows/workflows-with-an-idea-for-TCR.png
   TCR complete diagram
   

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9. Repository with TCR scripts
   https://github.com/islomar/tcr-workshop
   

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10. Kata: Fibonacci sequence
    

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11. Reminders for the set up
    ● You need Git installed
    ● Disable the auto-save mode
    ● Be sure your files get refreshed in your IDE (or you can force it easily)
    ● If you’re not using Java, Ruby or Python, there is a generic template
    

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12. First pomodoro… go!
    https://entregurus.com/the-pomodoro-technique/
    

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13. Bonus track
    ● Have you tried recursion? And memoization?
    https://medium.com/@nothingisfunny/memoization-improving-recursive-
    solution-for-fibonacci-sequence-problem-c02dab7a74e5
    ● Try another kata, e.g. substring kata:
    

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14. Second pomodoro… go!
    https://entregurus.com/the-pomodoro-technique/
    

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15. Opinions and feedback
    ● Did you learn anything new?
    ● Which was your main pain? With what did you struggle specially?
    ● Would you apply this during your daily job? Why? Or why not?
    ● Even if you don’t apply TCR tomorrow, is there any other practice you
    would consider to apply?
    

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16. Some possible downsides of TCR
    ● What if it doesn’t even compile?
    ○ Problem: a typo/syntax problem triggers the revert
    ○ Possible solution: include previous step to build/compile, BTCR
    ● Vanishing tests
    ○ Problem: everything reverts, including the tests
    ○ Maybe not a real problem: it forces you to nano-steps when writing tests!
    ○ Possible “solutions”:
    ■ commit the test first being pending/skipped
    ■ pass the negation of the test
    ● False green
    ○ Problem: If you don’t go red first, you might be adding a test which does nothing
    ○ Possible solution: negate the test after passing, and see how it reverts
    

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17. Final recap
    ● Fast feedback is more important than ever…
    ● Forces nano-baby-steps
    ● Forces you to think: "how can I make this change with a smaller step?"
    ● High frustration at the beginning?
    ● Beware the downsides…
    

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18. Interesting links
    ● https://medium.com/@kentbeck_7670/test-commit-revert-870bbd756864
    ● https://rachelcarmena.github.io/2018/11/13/test-driven-programming-workflows.html
    ● https://medium.com/@barlindhaug/how-to-test-commit-revert-e850cd6e2520
    ● https://blog.adrianbolboaca.ro/2013/03/taking-baby-steps/
    ● Kent Beck screencast: https://www.youtube.com/watch?v=ZrHBVTCbcE0
    ● https://medium.com/@tdeniffel/test-commit-revert-questions-answered-ddf012a1af97
    ● https://medium.com/@tdeniffel/all-downsides-and-open-questions-of-tcr-885bfee27146
    ● https://www.davidtanzer.net/david's%20blog/2019/03/06/test-commit-revert.html
    ● https://medium.com/@itortv/i-implemented-the-mars-rover-kata-through-tcr-test-commit-reve
    rt-and-these-are-my-7e11c40983a6
    

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