Run results for: reduce vs. filter + map vs. forEach - list 20m

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36

Browser: Chrome 117

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
reduce	4.2 Ops/sec
filter+map	2.0 Ops/sec
forEach	3.3 Ops/sec
for...of	2.1 Ops/sec

Script Preparation code:

function createTeamList(n) {
    var teamList = Array(n);
    for (var i = 0; i < n; i++){
        teamList[i] = {
            id: i,
            isSelected: true,
            name: `team ${i}`
        }
    }
    return teamList;
}

var searchableTeamList = createTeamList(20000000);

Tests:

reduce
const selectedTeamIds = searchableTeamList.reduce((ids, team) => { if (team.isSelected) { ids.push(team.id) } return ids; }, []);
filter+map
const selectedTeamIds = searchableTeamList.filter((team) => team.isSelected)?.map((team) => team.id);
forEach
const selectedTeamIds = []; searchableTeamList.forEach((team) => { if (team.isSelected) { selectedTeamIds.push(team.id) } });
for...of
const selectedTeamIds = []; for (const team of searchableTeamList) { if (team.isSelected) { selectedTeamIds.push(team.id) } }

Run results for: reduce vs. filter + map vs. forEach - list 20m

reduce

filter+map

forEach

for...of