import React from "react"; import { fireEvent, render } from "@testing-library/react"; export default class Counter extends React.Component { constructor(props) { super(props); this.state = { count: 0 }; } render() { return ( ); } } describe("sample counter test", function() { it("mutliple counts", function() { const { container } = render(); const button = container.getElementsByTagName("Button")[0]; fireEvent( button, new MouseEvent("click", { bubbles: true, cancelable: true }) ); fireEvent( button, new MouseEvent("click", { bubbles: true, cancelable: true }) ); expect(button.textContent).toEqual("Count 2"); }); });