@jetshop/core/experiments/integration.test.js

import React from 'react';
import { render, cleanup } from '@testing-library/react';
import useExperiment from './useExperiment';
import { StaticRouter } from 'react-router';
import { CookiesProvider } from 'react-cookie';
import Cookies from 'universal-cookie';
import ExperimentsProvider from './ExperimentsProvider';
import AnalyticsProvider from '../analytics/AnalyticsProvider';
import { ConfigProvider } from '../components/ConfigProvider';
import { ChannelProvider } from '../components/ChannelContext';
import { ChannelHandler } from '../ChannelHandler/ChannelHandler';
import { channels, selectedChannel } from '../test-utils/variables';
import { HelmetProvider } from 'react-helmet-async';
afterEach(cleanup);

const Experiment = () => {
  const first = useExperiment('test', 1);
  const second = useExperiment('test', 2);

  if (first) {
    return <div>First</div>;
  } else if (second) {
    return <div>Second</div>;
  } else {
    return <div>Original</div>;
  }
};

const setup = ({ cookies }) => {
  const channelHandler = new ChannelHandler({
    channels,
    selectedChannel
  });
  return render(
    <StaticRouter>
      <CookiesProvider cookies={cookies}>
        <HelmetProvider context={{}}>
          <ChannelProvider channelHandler={channelHandler}>
            <ConfigProvider config={{}}>
              <AnalyticsProvider config={{}}>
                <ExperimentsProvider>
                  <Experiment />
                </ExperimentsProvider>
              </AnalyticsProvider>
            </ConfigProvider>
          </ChannelProvider>
        </HelmetProvider>
      </CookiesProvider>
    </StaticRouter>
  );
};

describe('experiments', () => {
  describe('a/b testing', () => {
    it('renders original if no cookie was set', () => {
      const cookies = new Cookies({});
      const { getByText } = setup({ cookies });
      expect(getByText('Original')).toBeTruthy();
    });

    it('renders a specific variant if that variant was selected', () => {
      const cookies = new Cookies({
        optimizeExperiment: 'test.2'
      });
      const { getByText } = setup({ cookies });
      expect(getByText('Second')).toBeTruthy();
    });
  });
});