ツイートの会話スレッドに現れてるユーザーの列挙

sekimiya.js

import ThreadedUsers = require("./threadedUsers");
let threaded = new ThreadedUsers("https://twitter.com/sekimiya/status/666901649798000640");

threaded.fetch().then(users => console.log(users));

threadedUsers.js

import {JSDOM} from "jsdom";
import request from "request";

export default class ThreadedUsers {
  constructor(url) {
    this.target = url
  }

  fetch() {
    return (new Promise((resolve, reject) => 
      request.get({url: this.target}, (err, res) => err ? reject(err) : resolve(res))))
        .then(res => {
          this.rawDOM = new JSDOM(res.body);
          return this.rawDOM;
        })
        .then(dom => {
          this.users = this.listUser(dom);
          return this.users;
        })
  }

  listUser(dom) {
    return [...dom.window.document.querySelectorAll(".username.u-dir")]
      .map(u => u.textContent)
      .filter(u => u !== "@")
      .filter((u, i, arr) => 
        arr.slice(0,i)
        .filter(_u => _u === u).length === 0); 
  }
}