errorMessage.spec.js

import React from 'react';

import { render, getByText } from '@testing-library/react';

import ErrorMessage from '../ErrorMessage';

test('ErrorMessage renders correctly', () => {

    const { container } = render(

        <ErrorMessage error={{message: 'Something went wrong.'}}/>

    );

    expect(getByText(container, 'Something went wrong.')).toBeDefined();

    expect(container).toMatchSnapshot();

});

test('ErrorMessage does not render if error message is empty', () => {

    const { container } = render(

        <ErrorMessage error={{message: ''}}/>

    );

    expect(container.firstChild).toBeNull();

});