Yesterday I started working on a new React project which I am calling for the time being React Universal Blog. I set up my basic workflow, directory structure, and files. I set up for Jest testing, initially mocking out stylesheets and images to make sure everything was working properly. Later I’ll switch over to mocking CSS Modules, because I use them with POSTCSS. It’s not necessary to do that unless you intend to use Jest Snapshot Testing, and I do! I really want to check it out, and it just makes sense when you do use CSS Modules in development.

But that’s not why I am writing this post. I started this new project yesterday. And guess what big event took place yesterday! React 16.0 was released! And guess what happened in my project. I installed React 16.0.

Before I realized all this, I decided to make sure that my Jest configuration was working, so today I typed npm run test in Terminal. This is what was printed out to the console:


> react-universal-blog-app@1.0.0 test /Users/mariacam/Development/react-universal-blog-app
> jest

PASS  src/sum.test.js
PASS  src/App.test.js
● Console

console.error node_modules/fbjs/lib/warning.js:33
Warning: React depends on requestAnimationFrame. Make sure that you load a polyfill in older browsers. http://fb.me/react-polyfills

Test Suites: 2 passed, 2 total
Tests:       2 passed, 2 total
Snapshots:   0 total
Time:        1.669s
Ran all test suites.


Notice something different?


console.error node_modules/fbjs/lib/warning.js:33
Warning: React depends on requestAnimationFrame. Make sure that you load a polyfill in older browsers. http://fb.me/react-polyfills


That’s what reminded me that React 16.0 was released yesterday, and that my project must be using it! I wonder what other new goodies I will encounter!

Happy coding!