MergeSort example in JavaScript

MergeSorter.js

var MergeSorter = (function () {
	var merge = function (arr1, arr2) {
			var result = [];
			
			while (arr1.length > 0 && arr2.length > 0) {
				if (arr1[0] <= arr2[0]) {
					result.push(arr1.shift());
				} else {
					result.push(arr2.shift());
				}
			}

			while (arr1.length > 0) {
				result.push(arr1.shift());
			}

			while (arr2.length > 0) {
				result.push(arr2.shift());
			}
			return result;
		}, iterations = 0;

	return {
		mergeSort: function (arr) {
			iterations++;
			if (arr. length < 2) {
				return arr;
			}
			
			var splitPoint = Math.round(arr.length / 2),
				arrOne = arr.slice(0, splitPoint),
				arrTwo = arr.slice(splitPoint, arr.length);
			
			//console.log(iterations);
			return merge(this.mergeSort(arrOne), this.mergeSort(arrTwo));
		}
	};
}());

MergeSorter.mergeSort([4,5,2,4,2,-5,2,4,34,53,45,345,3,5,345,67,3,45,34,5]);
//[-5, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 34, 34, 45, 45, 53, 67, 345, 345]
MergeSorter.mergeSort(["andrew","kristina","john","greg"]);
//["andrew", "greg", "john", "kristina"]