Run results for: JavaScript spread operator vs Slice/Splice performance, passing

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:82.0) Gecko/20100101 Firefox/82.0

Browser: Firefox 82

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Array clone with spread operator	30015800.0 Ops/sec
Array clone with slice	18075970.0 Ops/sec
Array addition with spread operator	17071106.0 Ops/sec
Array addition with slice and push	16863518.0 Ops/sec
Array removal with spread operator	5350897.0 Ops/sec
Array removal with slice and splice	7181566.5 Ops/sec
Array update with spread operator	4846191.5 Ops/sec

Script Preparation code:

const ITERATIONS = 500000;
var index = ITERATIONS/2;
var n = Math.random();

var list = [];
for (let i = 0; i < length; i += 1) {
  list.push(Math.random());
}

Tests:

Array clone with spread operator
const clone = [...list];
Array clone with slice
const clone = list.slice();
Array addition with spread operator
const clone = [...list, n];
Array addition with slice and push
const clone = list.slice(); clone.push(n);
Array removal with spread operator
const clone = [ ...list.slice(0, index), ...list.slice(index + 1), ];
Array removal with slice and splice
const clone = list.slice(); clone.splice(index, 1);
Array update with spread operator
const clone = [ ...list.slice(0, index), n, ...list.slice(index + 1), ];

Run results for: JavaScript spread operator vs Slice/Splice performance, passing

Array clone with spread operator

Array clone with slice

Array addition with spread operator

Array addition with slice and push

Array removal with spread operator

Array removal with slice and splice

Array update with spread operator