Inefficient priority queue

pqueue.js

/**
 * Extremely inefficient priority queue.
 *
 * In a real program this would probably be implemented as a heap,
 * but this is good enough for this demonstration.
 */
function PQueue(comparator) {
  this.comparator = comparator || function(x, y) { return x - y }
  this.array = []
}

PQueue.prototype.add = function(item) {
  this.array.push(item)
  this.heapify()
}

PQueue.prototype.addAll = function(items) {
  for (var i = 0; i < items.length; ++i) {
    this.array.push(items[i])
  }
  this.heapify()
}

PQueue.prototype.heapify = function() {
  // lol
  this.array.sort(this.comparator)
}

PQueue.prototype.size = function() {
  return this.array.length
}

PQueue.prototype.shift = function() {
  return this.array.shift()
}