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
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
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
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 ?
5. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 You have the job but... 5
6. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Me at the time 6 Fibonacci master First IT job Need to learn everything about tests
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 7
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...
9. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Deno test command 9
10. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Useful options 10 • -A --allow-all to manage permissions • --filter to filter spec files • --inspect-brk to debug • --log-level to debug
11. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Limitations 11 • 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())
12. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 12 First test
13. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Assertions 1 / 3 13
14. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Assertions 2 / 3 14
15. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Assertions 3 / 3 15 Powerful Error assertions
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 16 And have access to all job interviews reports
17. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Doesn’t know Fibonacci at all !!! 17
18. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 18 Fibonacci 1 / 1 / 2 / 3 / 5 / 8 / 13 f(0) = 1 f(1) = 1 f(n) = f(n-1) + f(n-2)
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 19
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 20
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 21
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 22
23. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 23 deno benchmarks
24. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 24 Demno time
25. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 Conclusion 25 • 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
26. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 26 Thank you Questions ?
27. Paul SOUCHE Repository => https://github.com/paulsouche/unit-tests-in-deno Meetup Paris Deno 4/14/2020 27 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