Create-react-app: Expose Jest Setup Files

[MFry]

With Enzyme 3x come adapter packages. Its a bit tedious to insert into every test file

import { configure } from "enzyme";
import Adapter from "enzyme-adapter-react-15";

configure({ adapter: new Adapter() });

when you can create just a single setup file to serve all the tests.

[denkristoffer]

That's what src/setupTests.js is for: https://github.com/facebookincubator/create-react-app/blob/master/packages/react-scripts/template/README.md#initializing-test-environment

[MFry]

I can't believe I missed that! Thanks