TextField.test.js

import React from 'react';
import { fireEvent, render, screen } from '@testing-library/react';
import TextField from '@material-ui/core/TextField';

describe("TextField onChange demo", () => {
    it.each`
        initialValue | changeValue
        ${"test"}    | ${"changed"}
        ${"test"}    | ${"test"}
    `("given a text field with initial value '$initialValue' when changed to '$changeValue' then the onChange handler should be called", ({ initialValue, changeValue }) => {
        let onChangeCalled = null;

        render(<TextField id="testing" label="Testing" value={ initialValue } onChange={ (e) => onChangeCalled = true } />);

        fireEvent.change(screen.getByLabelText("Testing"), { target: { value: changeValue } });

        expect(onChangeCalled).toBeTruthy();
    });
});