Run results for: reduce vs flatMap test3

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:89.0) Gecko/20100101 Firefox/89.0

Browser: Firefox 89

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
reduce with forEach	1857.1 Ops/sec
flatMap	1363.2 Ops/sec
reduce with forEach (directly)	647.8 Ops/sec
flat	1454.4 Ops/sec
reduce with apply	708.3 Ops/sec
for with foreach	427.3 Ops/sec
for with apply	714.9 Ops/sec
nested for	2040.7 Ops/sec
reduce with while	3464.1 Ops/sec
while with foreach	419.4 Ops/sec
while with apply	724.9 Ops/sec
while with for	2017.6 Ops/sec
nested while	3884.6 Ops/sec
nested reduce	1215.3 Ops/sec

Script Preparation code:

var arr = new Array(10000).fill([1,2]);

Tests:

reduce with forEach
arr.reduce((res, x) => { x.forEach(item => {res.push(item)}) return res; },[]);
flatMap
arr.flatMap(x => x);
reduce with forEach (directly)
arr.reduce((res, x) => { x.forEach(res.push, res); return res; },[]);
flat
arr.flat();
reduce with apply
arr.reduce((res, x) => { Array.prototype.push.apply(res, x); return res; },[]);
for with foreach
const res = []; for (let i = 0; i < arr.length ; i++) { arr[i].forEach(res.push, res); }
for with apply
const res = []; for (let i = 0; i < arr.length ; i++) { Array.prototype.push.apply(res, arr[i]); }
nested for
const res = []; for (let i = 0; i < arr.length ; i++) { const x = arr[i]; for (let j = 0; j < x.length; j++) { res.push(x[j]); } }
reduce with while
arr.reduce((res, x) => { let i = x.length; while (--i > 0) { res.push(x[i]); } return res; },[]);
while with foreach
const res = []; let i = arr.length; while (--i > 0) { arr[i].forEach(res.push, res); }
while with apply
const res = []; let i = arr.length; while (--i > 0) { Array.prototype.push.apply(res, arr[i]); }
while with for
const res = []; let i = arr.length; while (--i > 0) { const x = arr[i]; for (let j = 0; j < x.length; j++) { res.push(x[j]); } }
nested while
const res = []; let i = arr.length; while (--i > 0) { const x = arr[i]; let j = x.length; while(--j > 0) { res.push(x[j]); } }
nested reduce
arr.reduce((res, x) => x.reduce((acc, y) => { acc.push(y); return acc; }, res),[]);