Enzyme expects an adapter to be configured
Add it to your test case file.
import React from 'react';import Adapter from 'enzyme-adapter-react-16';import { shallow, configure } from 'enzyme';configure({adapter: new Adapter()});test('message box', ()=> { ...})
Also, if you don't want to import your setupTests.js file into every test file, you can place it in your package.json folder:
"jest": { "setupTestFrameworkScriptFile": "./test/setupTests.js" }Update:
Note: setupTestFrameworkScriptFile is deprecated in favor of setupFilesAfterEnv.
The file 'setupTests' has to be imported to the test file:
import MessageBox from "../MessageBox";import { shallow } from 'enzyme';import React from 'react';import "../setupTests"test('message box', ()=> { ...})