Closing a websocket server in a unit test

import { send, App } from './mod.ts'

Deno.test('send', async (t) => {
  await t.step('should send a message with websocket', async () => {
    const app = new App()
    await app.listen({ port: 8881, hostname: 'localhost' })

    const socket = new WebSocket('ws://localhost:8881')
    socket.onopen = () => {
      send(socket, { hello: 'world' })
      socket.close()
      app.close()
    }
  })
})