bubble sort and merge sort in JS

sorting.js

bubbleSort = function(array){
  var swaps = 0;
  var comparisions = 0;
  var bool = true;

  if (array.length <= 1){
    bool = false;
    return array;
  }

  while (bool){
      var count = 0;
      for (var i=0; i<array.length-1; i++){
        comparisions++;
        if (array[i] > array[i+1]){
          swaps++;
          var a = array[i];
          var b = array[i+1];
          array[i] = b;
          array[i+1] = a;
        }
        else {
          count++;
        }
      }
      if (count == array.length-1){
          bool = false;
          console.log('swap: '+swaps);
          console.log('comparisons: '+comparisions);
          return array;
      }
    }
}



var mergeSort = function(array) {
 if (array.length <= 1) return array;
 var length = Math.floor(array.length / 2);
 var leftArr = array.slice(0, length);
 var rightArr = array.slice(length, array.length);

 var left = mergeSort(leftArr);
 var right = mergeSort(rightArr);

 return merge(left, right);
};

var merge = function(left, right) {
 var sorted = [];
 var iteration = left.length + right.length;
 for (var i = 0; i < iteration; i++) {
    if(right[0] !== undefined && left[0]!== undefined){
      if (left[0] < right[0]) { sorted.push(left.shift()); }
      else { sorted.push(right.shift()); }
    }
    else if( left[0] !== undefined){
      sorted.push(left.shift());
    }
    else{
      sorted.push(right.shift());
    }

 }
 return sorted;
};