November 2018
Beginner
502 pages
10h 22m
English
Content preview from Learn React with TypeScript 3
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Unit Testing with Jest
Building a robust suite of unit tests that catches real bugs and doesn't flag false positives as we refactor our code is one of the hardest tasks we do as software developers. Jest is a great testing tool that helps us meet this challenge, as we'll find out in this chapter.
Perhaps the easiest bits of an app to unit test are pure functions, because there are no side effects to deal with. We'll revisit the validator functions we built in Chapter 7, Working with Form, and implement some unit tests against them in order to learn how to unit test pure functions.
Unit testing components is the most common type of unit test we'll be carrying out while building our apps. We'll learn about it in detail, and leverage a library ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.