Sort by Two Fields in JS

sort.js

var obj = [
    { "name":'a', "count1": 1, "count2": 9 },
    { "name":'b', "count1": 10, "count2": 4 },
    { "name":'c', "count1": 21, "count2": 93 },
    { "name":'d', "count1": 10, "count2": 10 },
    { "name":'e', "count1": 10, "count2": 2  },  
    { "name":'f', "count1": 5,  "count2": 9  },
];


obj.sort(function(a, b) {
    return a.count1 - b.count1 || a.count2 - b.count2;
});

console.log(obj);

/*[
  [object Object] { count1: 1, count2: 9, name: "a" }, 
  [object Object] { count1: 5, count2: 9, name: "f" },
  [object Object] { count1: 10, count2: 2, name: "d" }, 
  [object Object] { count1: 10, count2: 4, name: "b" },
  [object Object] { count1: 10, count2: 10, name: "e" },
  [object Object] { count1: 21, count2: 93, name: "c" }] */