Run results for: Array.prototype.concat vs spread operator for joining arrays incrementally

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:63.0) Gecko/20100101 Firefox/63.0

Browser: Firefox 63

Operating system: Mac OS X 10.14

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
Array.prototype.concat	47038.5 Ops/sec
spread operator	16223.8 Ops/sec

Script Preparation code:

var arrays = [
	Array(100).fill(1),
	Array(100).fill(2),
	Array(100).fill(3),
	Array(100).fill(4),
	Array(100).fill(5),
];

Tests:

Array.prototype.concat
let combinedArray = []; arrays.forEach((array) => { combinedArray = combinedArray.concat(array) })
spread operator
let combinedArray = []; arrays.forEach((array) => { combinedArray = [ ...combinedArray, ...array, ] })