Run results for: Performance of JavaScript .forEach, .map and .reduce vs for and for..of with 1000p

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:149.0) Gecko/20100101 Firefox/149.0

Browser: Firefox 149

Operating system: Windows

Device Platform: Desktop

Date tested: 26 days ago

Test name	Executions per second
.forEach	104525.8 Ops/sec
for..of	103553.4 Ops/sec
for..of (destructuring)	83160.4 Ops/sec
.map	81226.0 Ops/sec
.map (destructuring)	85990.1 Ops/sec
.for (init array)	103495.0 Ops/sec
.reduce	99565.0 Ops/sec
.reduce (destructuring)	88471.0 Ops/sec
for..of (reduce)	96089.3 Ops/sec
for..of (reduce) (destructuring)	83354.0 Ops/sec

Script Preparation code:

function generateTestArray() {
  const result = [];
  for (let i = 0; i < 1000; ++i) {
    result.push({
      a: i,
      b: i / 2,
      r: 0,
    });
  }
  return result;
}

Tests:

.forEach
const array = generateTestArray(); array.forEach((x) => { x.r = x.a + x.b; });
for..of
const array = generateTestArray(); for(const x of array) { x.r = x.a + x.b; }
for..of (destructuring)
const array = generateTestArray(); const r = []; for(const {a, b} of array) { r.push(a + b); }
.map
const array = generateTestArray(); array.map(x => x.a + x.b)
.map (destructuring)
const array = generateTestArray(); array.map(({a,b}) => a + b)
.for (init array)
const array = generateTestArray(); const r = new Array(array.length); for (let i = 0; i < array.length; ++i) { r[i] = array[i].a + array[i].b; }
.reduce
const array = generateTestArray(); array.reduce((p, x) => p + x.a + x.b, 0);
.reduce (destructuring)
const array = generateTestArray(); array.reduce((p, {a,b}) => p + a + b, 0);
for..of (reduce)
const array = generateTestArray(); let r = 0; for (const x of array) { r += x.a + x.b; }
for..of (reduce) (destructuring)
const array = generateTestArray(); let r = 0; for (const {a,b} of array) { r += a + b; }

Run results for: Performance of JavaScript .forEach, .map and .reduce vs for and for..of with 1000p

.forEach

for..of

for..of (destructuring)

.map

.map (destructuring)

.for (init array)

.reduce

.reduce (destructuring)

for..of (reduce)

for..of (reduce) (destructuring)