Run results for: Array.concat vs Array.prototype.concat.apply

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36

Browser: Chrome 86

Operating system: Windows

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Array.concat	441341.2 Ops/sec
Array.prototype.concat.apply	388216.6 Ops/sec
Array.prototype.concat.apply short form	426644.2 Ops/sec
Array.prototype.concat.apply short form without new empty array instance in apply	434897.3 Ops/sec
Array.prototype.concat.apply short form without new empty array at all	418083.2 Ops/sec

Script Preparation code:

var array1 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array2 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array3 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array4 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array5 = Array(400).fill().map(() => Math.round(Math.random() * 40));

Tests:

Array.concat
var others = array1.concat(array2, array3, array4, array5);
Array.prototype.concat.apply
var others = Array.prototype.concat.apply([], [array1, array2, array3, array4, array5]);
Array.prototype.concat.apply short form
var others = [].concat.apply([], [array1, array2, array3, array4, array5]);
Array.prototype.concat.apply short form without new empty array instance in apply
var others = [].concat.apply(array1, [array2, array3, array4, array5]);
Array.prototype.concat.apply short form without new empty array at all
var others = array1.concat.apply(array1, [array2, array3, array4, array5]);

Run results for: Array.concat vs Array.prototype.concat.apply

Compare direct concat call with apply for multiple arrays concatenation

Array.concat

Array.prototype.concat.apply

Array.prototype.concat.apply short form

Array.prototype.concat.apply short form without new empty array instance in apply

Array.prototype.concat.apply short form without new empty array at all