Async while loop

promise_loop.js

'use strict';

var Promise = require('bluebird'),
    slice   = Array.prototype.slice,
    promiseLoop;

promiseLoop = function (fn, thisArg) {
    var argsArray = slice.call(arguments, 2);
    return function () {
        var pending = Promise.pending(),
            tick;
        tick = function () {
            return fn.apply(thisArg, argsArray)
                .then(function (loop) {
                    if (loop) {
                        process.nextTick(tick);
                    }
                    else {
                        pending.resolve();
                    }
                })
                .catch(pending.reject);
        };
        process.nextTick(tick);
        return pending.promise;
    };
};

module.exports = promiseLoop;