Run results for: JavaScript spread operator vs Slice/Splice performance - 2

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36

Browser: Chrome 91

Operating system: Linux

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Array clone with spread operator	12637350.0 Ops/sec
Array clone with slice	13544460.0 Ops/sec
Array addition with spread operator	4757603.0 Ops/sec
Array addition with slice and push	5011318.0 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);

Run results for: JavaScript spread operator vs Slice/Splice performance - 2

Array clone with spread operator

Array clone with slice

Array addition with spread operator

Array addition with slice and push