Swaps to elements of an array without mutating the original array. Returns the swapped array.

swapArrayElements.js

const swapArrayElements = (arr, index1, index2) => arr.map((val, idx) => {
  if (idx === index1) return arr[index2];
  if (idx === index2) return arr[index1];
  return val;
});
const foo = [1, 2, 3, 4, 5];
const swapped = swapArrayElements(foo, 1, 3); 
console.log(foo); //=> [1, 2, 3, 4, 5]
console.log(swapped); //=> [ 1, 4, 3, 2, 5 ]