import { configure } from 'enzyme'; import Adapter from 'enzyme-adapter-react-16'; configure({ adapter: new Adapter() }); expect.extend({ toHaveBeenCalledWithVariables(received, argument) { const receivedVariables = received.mock.calls[0][0].variables; const pass = this.equals(receivedVariables, argument); const message = () => `expected ${this.utils.printExpected(argument)} to match ${this.utils.printReceived(receivedVariables)}`; return { message, pass }; }, });