Sample of long stack traces in upcoming Q release: https://github.com/kriskowal/q/tree/long-stacks

1 q-long-stacks.js

"use strict";

var Q = require("q");

function doA() {
    return Q.resolve("A");
}

function doB() {
    return Q.resolve("B");
}

function doC() {
    return Q.resolve("C");
}

function doABC() {
    return doA().then(function aFulfillment() {
        return doB().then(function bFulfillment() {
            return doC().then(function cFulfillment() {
                throw new Error("boo!");
            });
        });
    });
}

doABC().done(); // Will re-throw the error, but with the long stack trace.

doABC().catch(function (err) {
    console.log(err.stack); // also works here
});

2 console-output.txt

Error: boo!
    at cFulfillment (C:\Users\Domenic\Dropbox\Programming\GitHub\q\test.js:21:23)
From previous event:
    at bFulfillment (C:\Users\Domenic\Dropbox\Programming\GitHub\q\test.js:20:26)
From previous event:
    at aFulfillment (C:\Users\Domenic\Dropbox\Programming\GitHub\q\test.js:19:22)
From previous event:
    at doABC (C:\Users\Domenic\Dropbox\Programming\GitHub\q\test.js:18:18)
    at Object.<anonymous> (C:\Users\Domenic\Dropbox\Programming\GitHub\q\test.js:29:1) # or 27:1 for the .done()

interesting. +1