app/javascript/components/Thermometer.test.js
import React from 'react';
import renderer from 'react-test-renderer';
import { IntlProvider } from 'react-intl';
import { Thermometer } from './Thermometer';
test('Renders as expected', () => {
const component = renderer.create(
<IntlProvider locale="en-GB" messages={{}}>
<Thermometer
title="Title"
donations={1000}
goal={600000}
currency={'GBP'}
/>
</IntlProvider>
);
expect(component.toJSON()).toMatchSnapshot();
});