Run results for: [] + push vs new Array() + index insertion (random insertion order) (fixed)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36

Browser: Chrome 133

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

new Array() + index insertion

7K/s

[] + push

4K/s

View exact numbers

Test name	Executions per second
✓ new Array() + index insertion	7,152 Ops/sec
[] + push	3,531 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

const ITEMS_COUNT = 100000
function shuffleArray(array) {
    for (var i = array.length - 1; i >= 0; i--) {
        var j = Math.floor(Math.random() * (i + 1));
        var temp = array[i];
        array[i] = array[j];
        array[j] = temp;
    }
  return array;
}
const ITEMS_IN_RANDOM_ORDER = shuffleArray(Array.from(Array(ITEMS_COUNT).keys()))

Tests:

[] + push
const arr = []; for (const i of ITEMS_IN_RANDOM_ORDER) { arr.push(i); }
new Array() + index insertion
const arr = new Array(ITEMS_COUNT) for (const i of ITEMS_IN_RANDOM_ORDER) { arr[i] = i }