I'd be curious as to why. Even if the answer is 321 by default, you should still be able to get 123 as the result by wrapping resolve

// should print 123
addEventListener('unhandledrejection', () => console.log(als.getStore()));

let reject;
als.run(123, () => new Promise((a,b) => reject = AsyncResource.bind(b)));
als.run(321, () => reject());

process.on('foo', () => console.log(als.getStore()); // context at emit
process.on('unhandledRejection' () => console.log(als.getStore()); // context at promise create

const ctx = new AsyncContext()

const queue = [];

const thenable = {
  then(onRes, _onRej) {
    queue.push("thenable: " + ctx.get());
    onRes();
  },
};

const out = ctx.run(1, () => {
  queue.push("new Promise");
  const p = new Promise(res => res(thenable));

  queue.push("p.then");
  const p2 = p.then(() => thenable);

  queue.push("p2.then");
  return p2.then(() => {
    queue.push("promise: " + ctx.get());
  });
});

queue.push("out.then");
out.then(() => {
  queue.push("done");
  //hook.disable();
  console.log(queue);
});

[
  'new Promise',
  'p.then',
  'p2.then',
  'out.then',
  'thenable: undefined',
  'thenable: undefined',
  'promise: 1',
  'done'
]