Run results for: Array.prototype.slice vs spread operator -- multiple cases

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser: Chrome 79

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Array.prototype.slice -- long -- no additions	6743.3 Ops/sec
spread operator -- long -- no additions	6000.4 Ops/sec
Array.prototype.slice -- long -- add another	1700.8 Ops/sec
spread operator -- long -- add another	967.9 Ops/sec
Array.prototype.slice -- short -- no additions	8379937.5 Ops/sec
spread operator -- short -- no additions	7834072.5 Ops/sec
Array.prototype.slice -- short -- add a few	2503321.2 Ops/sec
spread operator -- short -- add a few	5744029.0 Ops/sec

Script Preparation code:

var longArray = '0'.repeat(30000).split('').map(x => Math.random())
var short = [1, 2, 3]

Tests:

Array.prototype.slice -- long -- no additions
var other = longArray.slice()
spread operator -- long -- no additions
var other = [ ...longArray ]
Array.prototype.slice -- long -- add another
var other = longArray.slice().concat(longArray)
spread operator -- long -- add another
var other = [ ...longArray, ...longArray ]
Array.prototype.slice -- short -- no additions
var other = short.slice()
spread operator -- short -- no additions
var other = [...short]
Array.prototype.slice -- short -- add a few
var other = short.slice().concat([5, 6])
spread operator -- short -- add a few
var other = [...short, 5, 6]