Run results for: spread vs concat vs unshift vs push+sort

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:74.0) Gecko/20100101 Firefox/74.0

Browser: Firefox 74

Operating system: Ubuntu

Device Platform: Desktop

Date tested: 4 years ago

Script Preparation code:

var array = new Array();
for (let i = 1; i <= 1000; i++) {
  array.push(i);
}

Tests: