Unit test in deno

In this presentation we will see how to use the cli to run unit tests in deno, write assertions and have an overview of the benchmark API.

Transcript

1. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Unit tests in deno
   A std journey
   

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2. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Me myself and I
   @paul.souche
   paulsouche
   @paulsouche
   2
   

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3. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Disclaimer
   Deno is in v0.40.0 at the time I made this presentation.
   Some presented patterns may evolve in further releases.
   Purpose is to present the opinionated choices deno made in
   its architecture.
   3
   

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4. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   My first IT job interview
   4
   For the algorithm test we
   should begin with Fibonacci.
   Do you know it ?
   Yes, I studied it in
   highschool
   Ok great ! Could you begin
   with a unit test ?
   I never did a unit test of
   my life sorry ! but maybe
   can you help me ?
   

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5. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   You have the job but...
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6. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Me at the time
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   Fibonacci master
   First IT job Need to learn
   everything about tests
   

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7. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Resolution #1
   Always learn a language / framework / library / …
   through tests
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8. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Seven years later
   8
   deno test
   Hey Lilian ! Deno looks so
   great but how do you test ?
   Try yourself and make a
   presentation !
   Ok but what are the
   patterns ? What do you
   write ?
   Ok then...
   

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9. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
   Deno test command
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10. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Useful options
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    ● -A --allow-all to manage permissions
    ● --filter to filter spec files
    ● --inspect-brk to debug
    ● --log-level to debug
    

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11. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Limitations
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    ● No watch mode out of the box
    ● Specs are executed sequentially (no
    parallelism)
    ● Coverage is missing
    ● Files must respect pattern (can be tricked
    with Deno.runTests())
    

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12. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    First test
    

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13. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Assertions 1 / 3
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14. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Assertions 2 / 3
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15. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Assertions 3 / 3
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    Powerful Error assertions
    

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16. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Now I can do job interviews myself
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    And have access to all job interviews reports
    

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17. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Doesn’t know Fibonacci at all !!!
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18. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    Fibonacci
    1 / 1 / 2 / 3 / 5 / 8 / 13
    f(0) = 1
    f(1) = 1
    f(n) = f(n-1) + f(n-2)
    

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19. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    What I did at the time 1/3 : fibonacci
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20. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    What I did at the time 2/3 : fibonacci Rec
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21. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    What I did at the time 3/3 : famous unit test
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22. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    What I missed at the time : fibonacci memo
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23. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    deno benchmarks
    

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24. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    Demno time
    

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25. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
    Conclusion
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    ● deno dev experience is great (thanks to
    axetroy extension for vs code)
    ● testing std & cli are not production ready at all
    ● I hope the bench API will be kept
    

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26. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    Thank you
    Questions ?
    

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27. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020
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    Ressources
    ● repository (https://github.com/paulsouche/unit-tests-in-deno)
    ● testing std (https://github.com/denoland/deno/tree/master/std/testing)
    ● fibonacci & golden number (https://youtu.be/J6tcnc7LukM?t=971) (french)
    ● fibonacci & JavaScript
    (https://medium.com/developers-writing/fibonacci-sequence-algorithm-in-javascript-b253dc7e320e)
    ● demo meme (https://youtu.be/y_lYoENIffI) (check it out it's hilarious)
    Thanks to Paris Deno, axetroy, Aurélien & Mathieu
    

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