June 2019
Intermediate to advanced
192 pages
4h
English
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Chapter 1Test-Driven Development with Jest
Most tests are an afterthought. A programmer writes hundreds of lines of code to add a new feature to an application, followed by a perfunctory test or two. This “test-later” way of working has several drawbacks.
First, without tests, the programmer receives no feedback while writing the feature. If their approach turns out to be a dead-end, they won’t know it until they’ve finished the entire implementation.
Second, the tests the programmer writes after implementing the feature tend to be unthorough and unimaginative. Typically they confirm that the feature works along the “happy path”—that is, when used exactly as anticipated—rather than revealing potential bugs that might occur under edge case conditions. ...
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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.