Run results for: merge maps

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36 Edg/92.0.902.73

Browser: Chrome 92

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
Merge spread	56518.6 Ops/sec
merge foreach	71993.4 Ops/sec
merge 2 foreach	94463.4 Ops/sec

Script Preparation code:

const arr = [];
const arr2 = [];
for (let i = 0; i < 100; i++) {
    arr.push([i, 'Val' + i]);
    arr2.push(['key' + i, 'Val' + i]);
}

var map1 = new Map(arr)
var map2 = new Map(arr2)

Tests:

Merge spread
var map3 = new Map([...map1, ...map2]);
merge foreach
var map4 = new Map(map1) map2.forEach((val, key) => {map4.set(key, val)})
merge 2 foreach
var map4 = new Map() map1.forEach((val, key) => {map4.set(key, val)}) map2.forEach((val, key) => {map4.set(key, val)})

Run results for: merge maps

Merge spread

merge foreach

merge 2 foreach