Minimal repro of superagent redirect following breaking cookies

superagent-redirect-cookie-bug-repro.js

import express from 'express';
import superagent from 'superagent';
import Cookies from 'cookies';

const app = express();

app.get('/set-cookies', function (req, res) {
  const cookies = new Cookies(req, res);
  cookies.set('cookie_with_domain', 'with_domain', { domain: 'localhost' });
  cookies.set('cookie_without_domain', 'without_domain');
  res.status(200).end();
});

app.get('/set-cookies-and-redirect', function (req, res) {
  const cookies = new Cookies(req, res);
  cookies.set('cookie_with_domain', 'with_domain_in_redirect', { domain: 'localhost' });
  cookies.set('cookie_without_domain', 'without_domain_in_redirect');
  res.redirect('/read-cookies');
});

app.get('/read-cookies', function (req, res) {
  const cookies = new Cookies(req, res);
  const withDomain = cookies.get('cookie_with_domain');
  const withoutDomain = cookies.get('cookie_without_domain');
  res.json({'cookieWithDomain': withDomain, 'cookieWithoutDomain': withoutDomain});
});

app.listen(8080, async () => {
  try {
    // 1. Create an agent
    const agent = superagent.agent();

    // 2. Set a cookie in a standard response (without a redirect)
    await agent.get('http://localhost:8080/set-cookies');
    const response = await agent.get('http://localhost:8080/read-cookies');
    console.log(response.body);

    // 3. Try to set the same cookie in a followed redirect
    const redirectResponse = await (agent.get('http://localhost:8080/set-cookies-and-redirect').redirects(1));
    console.log(redirectResponse.body);
  } finally {
    process.exit(0);
  }
});