JavaScript Testing Basics with Jest

An overview of unit testing with Jest, covering the main features it offers. This includes: initial setup and writing of first tests, watch mode usage, common expect statement matchers in use, test filters, coverage reports, and snapshots.

This video is also part of a playlist of Jest content:

00:00 - What we'll cover
03:06 - Project setup and watch mode
05:45 - Creating tests
10:55 - Red, Green example
13:43 - Expect statements
25:17 - Add test script and git
27:08 - Coverage
36:43 - Test run control utility methods
40:08 - Test filters
41:27 - What files coverage includes by default
46:07 - Snapshots
53:12 - Wrap-up

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[Andrea-Giachetto]

The quality of your videos is amazing! With this pace, you will be the next big tech channel :)

[Scetils]

Pretty late to the party but in terms of not having to reopen the Coverage Report each time you run tests.
If you open the coverage index.html file with the VCCode LiveServer extension it will listen for changes and refresh. You'd have to open it initially but it will update in the browser when the file changes.

Awesome video. About to work my way through the rest of the playlist :)

[pedro.britto]

It's really pleasant to hear you explaining things. It's pretty nice to follow. Thanks!

[hyfydistro]

Testing is so underrated! It doesn't get that much attention than it should. 😭 People don't usually pick it up until they fully utilise the programming language either. I'm just picking up Jest now. I wasn't advised when to pick it up in my earlier time learning to program. Thank you for putting this video up. ❤ Much appreciated!

[testquality]

Jimmy! Thank you for this great video.
Software Testing is undervalued but when done iteratively, it helps produce major testing criteria and also reduces issues by focusing on defects or unpleasant delays early in the Software Delivery Life Cycle. Along with a right Test Management tool, it may help to reduce a lot of time and effort to perform the many tasks involved in testing either with Jest, JUnit or any other Testrunners.

[mpcabete]

first video of yours that I saw. Subscribed! I am exited to see the rest of them

[christiantirado]

Love this video man! Very informative and explained in a way that's concise and easy to digest :)

[havefun]

Thanks for the video. Hope more advance video such as a real react app with Unit test

[simpleprogramming]

I love your channel man. very useful stuff here <3 thanks

[srenschmidt]

Awesome video and great content quality! Love it :-D

[samueltorres]

Awesome video! In the future could you do a jest series where you go through building a real world app using TDD with Jest and some form of Javascript (node, react) etc...? Just a thought. Thanks again

[adithyakiransekar]

Great video, how does snapshot testing compare with using chromatic? Is there a use case to use both?

[santhoshraghavpidathala]

Could you please make a video on promises, async and generators by taking real time example or REST API . Without using setTimeOut.. functions etc

[harilovableterror]

Hey Swash, Followed your jest videos for creating my unit test coverage and it was very helpful. When I tried to run the same npm test in looper for CI, I am getting message - Ran all test suites but still not exiting from the test and next job is the pipeline is not kicked off. can you help mw with this.

[gager]

Which camera and microphone are you using? The quality is awesome

[MoraisSanFoo]

Nice, but what about mocking function, modules, etc.?

[ayodejijoseph]

Great video dude, love how you teach, would love you to set it up from scratch in your future video, am an SDET need to work more closely in supporting my devs in writing unit test and integration test, so need to bump up my understanding on this tool. Love Jest, can you also make video on Axios?

[AbdurrahmanHafez]

Perfect🚀 one of the best
Could you please tell me the name of your font ?

[Goku]

Thank yo for this video. Very useful. Do you have a config file to enable ESM?

[amannegi]

WOW Keanu Reeves " us code WOWWW..