Run results for: 2unshift vs2 spread vs concat

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 YaBrowser/21.8.0.1716 Yowser/2.5 Safari/537.36

Browser: Yandex Browser 21

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
array.unshift(0);	41257.8 Ops/sec
array = [0].concat(array)	2192.4 Ops/sec
[0, ...array]	372.6 Ops/sec

Script Preparation code:

var array = [];
for (let i = 0; i < 100000; i++ ) {
    array.push(i)
}

var test = null;

Tests:

array.unshift(0);
test = array.unshift(0);
array = [0].concat(array)
test = [0].concat(array)
[0, ...array]
test = [0, ...array]

Run results for: 2unshift vs2 spread vs concat

array.unshift(0);

array = [0].concat(array)

[0, ...array]