使用socket.io redis适配器运行所有测试后，Jest挂起

Question

我有一个使用Redis适配器使用Socket.IO的Node.JS服务器。运行Jest测试时，所有测试都已运行后，Jest进程将挂起。我已将代码最小化为以下代码，以便能够重现。导致此问题的是Redis适配器。我还需要做什么？

app-test.ts

import express from 'express';
import fse from 'fs-extra';
import * as http from 'http';
import socketIo from 'socket.io';
import SocketIORedis from 'socket.io-redis';
import { CONFIG_TYPE, CONFIGS_PATHS } from '../../constants';

class Server {
  // Bootstrap the application.
  public static bootstrap(): Server {
    return new Server();
  }

  public app: express.Application;
  public server: http.Server;
  private io: SocketIO.Server;

  constructor() {
    // Create expressjs application
    this.app = express();

    // Create server
    this.createServer();
  }

  public shutdown(): void {
    this.io.close();
    this.server.close();
  }

  private async createServer() {
    this.server = http.createServer(this.app);
    this.io = socketIo(this.server, { transports: ['polling', 'websocket'] });
    const redisConfig = await fse.readJson(CONFIGS_PATHS[CONFIG_TYPE].REDIS);
    const redisAdapter = SocketIORedis(redisConfig);
    this.io.adapter(redisAdapter);

  }
}

// Bootstrap the server
const server = Server.bootstrap();
export default server;

app-test.spec.ts

import app from './app-test';

describe('test', () => {
  afterAll((done) => {
    app.shutdown();
    done();
  });

  it('fake test', () => {
    expect(true).toBeTruthy();
  });
});