funfunfunfun.js

const { Readable } = require('stream');

const oldOn = Readable.prototype.on;
Readable.prototype.on = function on(name, fn) {
  oldOn.apply(this, arguments);

  if (name !== 'allData' || this._readableState.objectMode) {
    return;
  }

  const bufs = [];
  oldOn.call(this, 'data', d => bufs.push(d));
  oldOn.call(this, 'end', () => {
    this.emit('allData',
      Buffer.isBuffer(bufs[0]) ? Buffer.concat(bufs) : bufs.join(''));
  });

  return this;
};
Readable.prototype.addListener = Readable.prototype.on;

require('events').prototype.whence = function (name) {
  return new Promise(res => this.once(name, res));
};

// --------------------------

const https = require('https');
async function get (url) {
  const res = await https.get(url).whence('response');
  return res.whence('allData');
}

(async function main () {
  console.log(await get('https://nodejs.org'));
})();