Run results for: spread vs push vs ifSpread vs ifPush

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36

Browser: Chrome 87

Operating system: Mac OS X 10.15.6

Device Platform: Desktop

Date tested: 3 years ago

Script Preparation code:

var arr1 = [1,32,4,34,5,6,7,34,5,6];
var arr2 = [5,232,545,56,223,5,1,6,30];

Tests:

spread
var resultSpread = [...arr1, ...arr2];
push
for (let index = 0; index < arr2.length; index++) { const element = arr2[index]; arr1.push(element); }
ifPush
for (let index = 0; index < arr2.length; index++) { const element = arr2[index]; if (arr1.findIndex((item) => item === element) < 0) { arr1.push(element); } }
ifSpread
for (let index = 0; index < arr2.length; index++) { const element = arr2[index]; if (arr1.findIndex((item) => item === element) < 0) { arr1 = [...arr1, element]; } }