Run results for: Spread vs Array.prototype.concat

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

Browser: Chrome 69

Operating system: Mac OS X 10.14.0

Device Platform: Desktop

Date tested: 6 years ago

Test name	Executions per second
Array.prototype.concat	0.0 Ops/sec
Spead	0.7 Ops/sec

Script Preparation code:

function generateRandomNumbers(m) {
  const array = new Uint32Array(m);
  window.crypto.getRandomValues(array);
  return array;
}

function generateRandomArrays(n, m) {
  const array = [];
  for (let i = 0; i < n; i++) {
	array.push(generateRandomNumbers(m))
  }
  return array;
}


var array = generateRandomArrays(1e3, 1e2);

​x
 
function generateRandomNumbers(m) {  const array = new Uint32Array(m);  window.crypto.getRandomValues(array);  return array;}​function generateRandomArrays(n, m) {  const array = [];  for (let i = 0; i < n; i++) {    array.push(generateRandomNumbers(m))  }  return array;}​​var array = generateRandomArrays(1e3, 1e2);

Tests:

Array.prototype.concat
b = array.reduce((accumulator, value) => accumulator.concat(value));
b = array.reduce((accumulator, value) => accumulator.concat(value));

Spead

b = array.reduce((accumulator, value) => [...accumulator, ...value])

 
b = array.reduce((accumulator, value) => [...accumulator, ...value])