At the time of writing these notes, Create React App uses React 16. In order to use Enzyme with React 16, we need to install the enzyme-adapter-react-16 package:
npm install --save-dev enzyme-adapter-react-16
With this package, we can now configure our application to use this adapter. In src/App.test.js:
// ...
import { configure } from 'enzyme'
import Adapter from 'enzyme-adapter-react-16'
configure({ adapter: new Adapter() })
// ...More information about the enzyme-adapter-react-16 package and what package to use with specific versions of React can be found in the resources.