Run results for: Initializing array with map function

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:133.0) Gecko/20100101 Firefox/133.0

Browser: Firefox 133

Operating system: Windows

Device Platform: Desktop

Date tested: 16 days ago

Test name	Executions per second
[...Array(n).keys()].map(filler)	1075.4 Ops/sec
Array.apply(null, { length: 4 }).map(filler)	508.5 Ops/sec
Array.from	2719.5 Ops/sec
Array(n).fill(undefined).map(filler)	1634.4 Ops/sec
for loop push	3437.7 Ops/sec

Script Preparation code:

var n = 100000; // 100k
function filler(v, i) {
    return i ** 2;
}

Tests:

[...Array(n).keys()].map(filler)
[...Array(n).keys()].map(filler);
Array.apply(null, { length: 4 }).map(filler)
Array.apply(null, { length: n }).map(filler);
Array.from
Array.from({ length: n }, filler);
Array(n).fill(undefined).map(filler)
Array(n).fill(undefined).map(filler)
for loop push
const arr = []; for (let i = 0; i < n; i++) { arr.push(filler(null, i)); }