Unit testing in JavaScript Part 1 - Why unit testing?

Today, we are going to start exploring unit testing in JavaScript.
I think of Unit testing as a software development technique where you break your software up into small, isolated units and write automated tests that ensure that each unit works as expected.
My main motivation for doing unit testing is to keep complexity from overwhelming me. And that is what we're going to explore in this first video - we're going to look at how a new piece of code always starts out simple but very quickly gets too much to keep all in our heads.
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"it's completely normal to be afraid of the new things but remember that new things become less scary the more you use them" ❤

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3:57

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Love this format ! It looks way more like a show, the new personas are a really nice asset. Keep on rockin'

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glad you like them!

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”even with reduce, that I’m uncomfortable with - because it’s new” 🙄😂🤣 (Unfortunately a very realistic statement 😥)

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I saw .reduce, paused, googled it, came back, was still feeling that feel a bit. "AH NEW THINGS"

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The inner dialog between feelings, benefits, and the guy in the sunglasses in this episode is hilarious and insightful. This show rocks!

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I've been wanting this series since I started watching! The multiple personalities is a nice touch. Thanks for all your hard work, mpj!

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MPJ, you are the best author of video lessons I ever see. Fun, short, motivated and very energetic videos. You are AWESOME!

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Fantastic episode. Loved the different characters arguing out their respective positions. Great work MPJ

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I love the characters thrown in about reduce, super fun! :)

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+iam13islucky glad you liked them!

[@minademian]

The staging of the inner conversations in a developer is just brilliant. Helps validate the chaos often experienced. Tack! 😀

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You put the fun in function 😁 Great content - informative and entertaining. Love the delivery and energy!

[@Francisco-ph4bp]

Loved this one. I liked the emphasis on feelings and the argument about the way of thinking "a rockstar programmer could keep this function on their brain" not being scalable is so true and I never thought about it. Super helpful and epiphany inducing video. Big theater kid vibes haha ❤

[@KimHogeling]

Dat cliffhanger 🤘 This was done really well! Looking forward to next week 👋☺️

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Love this episode! It was informative, addresses software by design, was very entertaining and eccentric in the best possible way. Thanks MPJ.

[@amgdeg4897]

This felt less like learning and more like a fun journey... A fun fun journeeeey

[@doubledoorsd4]

Man that "doesn't that mean that I'm dumb" bit. This is so me. Really uplifting to hear you say that man! .. and yeah a great start to understanding unit testing :)

[@craftonrobert5236]

Probably one of your best episodes, love the personas - you need to bring them more into your series!

[@pdowner1]

Man! I wish I didnt have to wait for the next video. Thank you so much for breaking this down like this and starting with the Why first, you've really helped me to wrap my head around it. I have so many questions after watching this video and thats a good thing!

[@mutosui]

The part on how you should think about when deciding if you should break a function in smaller ones is absolutely amazing (and it's no even the main topic!)

[@funfunfunction]

Thanks! In a way it’s a sub topic, but in away it’s the main one for me. It’s very easy to fool yourself into thinking that you’ve modularized something if you don’t actually test it as a module

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I'm so excited for this episode and hopefully the series this kicks off!!!

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Watched a video first time on this channel and just love the presentation which made the concepts stick into the head with the help of creative visuals.

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FunFunFunction motivates me to write unit testing in everyday development with prior test target setup with triangulation. Unit tests provide results, which provide immediate feedback to develop codes in flow(zen) modes. More than great lectures, FunFunFunction stimulates me to love coding passionately. Awesome work. Thanks.

[@kevinb1594]

I need Part 2! I hope this is a long/in depth series because even though I know the WHY of unit testing, I've never been able to get the 'how' with javascript. I really want to get my head around TDD + javascript.

[@nicholasnewell3358]

Fantastic video! Loved the characters and thinking processes going on. Thanks for approaching stuff with a easily digestible format for us scrubs :)

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I’m half way through the video and I am crying laughing - and learning . This is what made me so hooked on this Ch. I often wonder why you have not exploded - the quality of your content is amazing. Truly a show and not a tutorial.

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"Doesn't this mean that I'm dumb?" Never a more relatable sentiment in this whole career change journey... Thank you for this!

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this is so fun to watch! i dont get sleepy learning new stuff, thank you for this awesome content

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I really appreciate these mini episodes, thanks for inspiring me :D

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Seriously you nailed it the battle on the code reviewers. The different personalities you played.

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This episode aims at fans who didn’t see all previous episodes. Diehard followers like myself learned nothing new, although I leave a like because I’m excited for part 2 and also because I missed you mpj! Have a great week!

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And the multi-mpj thingy kept it fresh (? hahaha

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I learned about MPJ's schizophrenia

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no one asked

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Hey MPJ! I love the characters. It helps me better understand conflicting views, and how/why some decisions come about. It’s like Plato’s style for the Allegory of the Cave, applied to coding, and I love it. Thanks again for all you do.

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ooh did not think of that!

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Thanks for going full time! Love this stuff

[@sreid70]

Great video. Enjoy how you explain the "why" of unit testing. Can't wait for then next video. I don't do ANY unit testing, mostly because I don't work in a team environment. I can see how unit testing would be useful, but I haven't been able to justify the extra time it takes when I am working against deadlines on my own. I realize it should be done, however, I've been getting away without doing it....so far...

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I’ve been waiting for some good videos from you about Unit Testing! Finally :)

[@ISTefrain]

I would like to find what is the best word to describe how excellent this video is but I think it doesn't exist. Thanks a lot, mpj!

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You're one of the best teachers i've ever encountered in my life

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Definitely you rock on teaching man! Many thanks and keep this awesome work! Peace from Brazil!

[@fmkoba]

years later to the party, but the video was genius, the discussion follows exactly the thought process we face when working on these cases

[@lsd22252]

Clever use of the pause button. So relatable. Coding drives you crazy and you've fully embraced the feeling. Maybe those voices in your head are worth reducing to a total of one in the interest of sanity. You're a one man party . . . keep up the good work.

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love the new intro, and the hair ofc :D, i also really like the background music used. keep it up!!

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Dear sir this discussion with yourself was one of the most interesting conversation i have ever heard about complexity

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This was the most enjoyable technical discussion :) Bravo man !

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Loving it - bring on the unit testing!

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Love all your videos, but the multiple view points expressed through the wacky characters really made this video amazing!

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Your videos are very cool and useful. You cover different points of view and that's how it happens in real life. I wish you keep going with your 'Fun Fun Function':-)

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Great video and love the intro lol kaffe drop was hilarious !

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you're way funnier in your natural habitat, I came from DevTips and I don't intend to go anywhere until I finish watching every single video you make xD

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Very insightful! Thanx so much MJ

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This gave me a serious case of deja vu. Good stuff.

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I loved how the MPJMEs changed wardrobe mid show, got all confused on who was the one wearing sunglasses, funny as hell, give this guy an Emmy

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Amazing.. like you're reading my mind live. Thank You!

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This was fantastic!

[@tourk1234]

MPJ, you outdone yourself :) Congratulations. Good stuff. I would like to add that sometimes when project is manageable size, with limited expectation of project growth and you are almost positive that you are going to develop that project only by yourself. Then unit testing makes more sense for really hard to test parts of project only. Overtesting in that particular situation is possible waste of time. Exception to that is requirement that project must work 100% of the time.

[@funfunfunction]

Yeah, absolutely. I agree with you 100%. I actually had a segment about that, but ended up deleting it as it diluted the narrative, and I ended up focusing on the reason that applies to all devs, not just teams.

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I freaking love this episode. Hilarious! 😀

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Good episode. Loved the new format. The only problem is that the music was way too loud.

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Great work. This format is awesome

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at 5:30, you said "even with this reduce, I am not comfortable with, because it's new". I laugh so much. It speaks my heart. Awesome, it make the show entertaining!

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Excellent video man! Thanks

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Well done! I like your different characters!

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Awsome hello from 2020! Searching for a great tutorial for juniors and found this! You are brilliant))

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Year: 2022. Still valid, still funny, still valuable. Thank You for lesson.

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You are a fantastic teacher. Thank you.

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Great introduction into unit testing

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I was searching for "testing' in your channel and saw this video, started to search for part 2 until realized this video has just published a few hours before that.

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You hit every thought I have when coding!

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Such a good episode. Deserves more views.

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Nice characters! Keep on the hard work. :D

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Amazing, amazing videos! So glad you address these topics. I just watched the second video, and I'm curious: Is writing in a TDD behavior ultimately mainly for writing API, or is it also just general good habit for everyday coding?

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[@illusionarybliss]

excellent thoughts on how you would break up a function; you would need to be able to break it up conceptually

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First time watcher, subscribed. Lets do this!

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Can't wait for the next Monday. ^^

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I love your videos dude!

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Awesome channel bro!

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Wallaby is telling me you have already wrote your tests and they are pretty good ;-) Anyway awesome videos and refreshing to see a developer having fun with it!

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Thanks man, great stuff

[@antonioaugustocastanheira5966]

Awesome! Really helpful

[@NicholasMarshall]

A prime example of why the two dudes talking is a common format. Using two dudes requires less hats. On the other hand, it was neat once accepted that you were sharing your inner monolog.

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This was brilliant

[@fragrantbloom]

Great video!!!

[@johongirrahimov2343]

SUMMARY: 1. Unit testing is a software development technique where you divide software up into smaller isolated parts and write tests for each of those isolated parts to verify that they work as expected 2. In order to break larger function into smaller isolated functions, you have to be able to break that function conceptually as well otherwise you are just spreading the problem into different places which increases complexity instead reducing ADDITIONAL INFO: In TDD, we write automated tests for the code before that code is written. In Unit testing, we write tests before or while writing ode, or after writing code

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when & where we use TDD?

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You're an awesome programmer and an acteur man. You should mix those thing and start some kind of programming show :)

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Nice one MPJ!

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Yeah. incredibly useful as always.

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You're very good at explaining things :)

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love the way you explain. :)

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This guy has value. How am I so late to the show?