Run results for: map vs reduce/concat vs reduce/push vs reduce/spread

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.36

Browser: Chrome 104

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Array.map()	4480210.5 Ops/sec
Array.reduce().concat()	943257.8 Ops/sec
Array.reduce().push()	4384685.5 Ops/sec
Array.reduce() spread	2477613.2 Ops/sec

Script Preparation code:

var object = {
    a: {
        foo: 'bar'
    },
    b: {
        foo: 'bar'
    },
    c: {
        foo: 'bar'
    },
    d: {
        foo: 'bar'
    },
    e: {
        foo: 'bar'
    },
    f: {
        foo: 'bar'
    },
    g: {
        foo: 'bar'
    },
}

Tests:

Array.map()
const array = Object.values(object).map(({ foo }) => foo)
Array.reduce().concat()
const array = Object.values(object).reduce((arr, { foo }) => { return arr.concat(foo); }, []);
Array.reduce().push()
const array = Object.values(object).reduce((arr, { foo }) => { arr.push(foo); return arr }, []);
Array.reduce() spread
const array = Object.values(object).reduce((arr, { foo }) => { return [...arr, foo]; }, []);

Run results for: map vs reduce/concat vs reduce/push vs reduce/spread

Array.map()

Array.reduce().concat()

Array.reduce().push()

Array.reduce() spread