Run results for: Flatten array of array v3

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser: Chrome 111

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
iterate / push	26205.8 Ops/sec
reduce / spread	3296.1 Ops/sec
reduce / concat	8366.2 Ops/sec

Script Preparation code:

var arr = [];
for (let i = 0; i < 100; i++) {
  let internal = [];
  for (let j = 0; j < 100; j++) {
    internal.push(i * 100 + j);
  }
  arr.push(internal);
}

Tests:

iterate / push
let flattened = []; for (let i = 0; i < arr.length; i++) { let internal = arr[i]; for (let j = 0; j < internal.length; j++) { flattened.push(internal[j]); } }
reduce / spread
let flattened = arr.reduce((acc, i) => [ ...acc, ...i], []);
reduce / concat
let flattened = arr.reduce((acc, i) => acc.concat(i), []);
reduce / push
let flattened = arr.reduce((acc, i) => { i.forEach(e => acc.push(e)); return acc; }, []);
array.flat
let flattend = arr.flat();
frray.flatMap
let flattend = arr.flatMap((x) => (x));

Run results for: Flatten array of array v3

iterate / push

reduce / spread

reduce / concat

reduce / push

array.flat

frray.flatMap