PriorityQueue priorities messed up?

Created by: yonivy

It seems that the jobs do not adhere to the priorities.

I didn't see any tests related to actually checking we get a correct order of execution, so I ran some myself.

This is just the "let's log it out" version, no assertions.

queue = new PriorityQueue(queueName);

var lowPJobs = [], mediumPJobs = [], highPJobs = [];

for(var i = 0; i < 4; i++) {
    lowPJobs.push(queue.add({p: 2}, {priority: 'normal'}));
    mediumPJobs.push(queue.add({p: 1}, {priority: 'medium'}));
    highPJobs.push(queue.add({p: 0}, {priority: 'high'}));
}

// wait for all the jobs to enter the queue
Promise
    .all(lowPJobs, mediumPJobs, highPJobs)
    .then(function() {
        queue.process(function(job, done) {
            console.log(job.data);
            done();
        });
    });

and the output is always

{ p: 0 }
{ p: 0 }
{ p: 1 }
{ p: 1 }
{ p: 1 }
{ p: 1 }
{ p: 2 }
{ p: 2 }
{ p: 2 }
{ p: 2 }
{ p: 0 }
{ p: 0 }

this 'pattern' is repeating every time the 'highest' priority is present more than 2 times.

Does anybody know anything about why and maybe a clue to what should be fixed? I've skimmed through the code and nothing really caught my eye.