Multi Level Sorting with JavaScript

sort.js

const multilevelsort = (records, order) => records.sort(chainSortBy(order))

const sort_by = ({ key, direction }) => {
  return function (a, b) {
    a = a[key]
    b = b[key]
    
    return a == b ? 0 : [-1, 1][+(direction === 'ascending')] * ((a > b) - (b > a))
  }
}

const chainSortBy = order => {
  return function (a, b) {
    for (let k in order) {
      let res = sort_by(order[k])(a, b)
      
      if (res != 0)
        return res
    }
    
    return 0
  }
}

test.js

var records = [
  {name:"christian", age:40, job:"developer"},
  {name:"andrew", age:48, job:"developer"},
  {name:"elisabeth", age:31, job:"floor manager"},
  {name:"oscar", age:61, job:"floor manager"},
  {name:"gisela", age:51, job:"area manager"},
  {name:"buffy", age:27, job:"trainee"},
  {name:"carl", age:23, job:"trainee"}
];
var order = [
  {key: "job", direction: "ascending"},
  {key: "age", direction: "descending"}
];
var result = [
  {name:"gisela",age:51,job:"area manager"},
  {name:"andrew",age:48,job:"developer"},
  {name:"christian",age:40,job:"developer"},
  {name:"oscar",age:61,job:"floor manager"},
  {name:"elisabeth",age:31,job:"floor manager"},
  {name:"buffy",age:27,job:"trainee"},
  {name:"carl",age:23,job:"trainee"}
];
multilevelsort(records,order) === result