Adding unshift to add to front of the queue

[mattpodwysocki]

I'm a developer on the Thali Project at Microsoft, and we'd love to use your library. We currently have our own implementation of a PromiseQueue which has associated tests in testPromiseQueue.js.

What we're missing from this implementation is the ability to add items to the beginning of the queue as we file things in priority order. We'd rather just use something simple instead of a priority queue, so your project is perfect. All we'd want to add is something like the following?

    /**
     * @param {Function} promiseGenerator
     * @return {LocalPromise}
     */
    Queue.prototype.unshift = function (promiseGenerator) {
        var self = this;
        return new LocalPromise(function (resolve, reject, notify) {
            // Do not queue to much promises
            if (self.queue.length >= self.maxQueuedPromises) {
                reject(new Error('Queue limit reached'));
                return;
            }

            // Add to queue
            self.queue.unshift({
                promiseGenerator: promiseGenerator,
                resolve: resolve,
                reject: reject,
                notify: notify || noop
            });

            self._dequeue();
        });
    };

If you are amenable to adding it, with the choice of your name of course, then we'd happily file the PR with any documentation changes and tests included. Thoughts?

[jbnicolai]

I'd definitely like to see this in 👍

[mattpodwysocki]

@jbnicolai thanks, this should be pretty easy. @azproduction any interest in this?

[azproduction]

@mattpodwysocki looks good! Sort of jumpTheQueue() :)

[rops]

+1

[azproduction]

There are some pending changes in PR.