Run results for: Filtering duplicates

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser: Chrome 114

Operating system: Linux

Device Platform: Desktop

Date tested: 10 months ago

Test name	Executions per second
Set + filter	527.2 Ops/sec
Reduce	528.9 Ops/sec
Set	493.0 Ops/sec

Script Preparation code:


var array = [];
for (let i = 0; i < 100000; i++) {
    array.push({
        id: Math.floor((Math.random() * 10) + 1),
        name: 'name' + i
    });
}

Tests:

Set + filter
const seen = new Set(); const filtered = array.filter(el => { const duplicate = seen.has(el.id); seen.add(el.id); return !duplicate; });
Reduce
const filtered = array.reduce((acc, current) => { const x = acc.find(item => item.id === current.id); if (!x) { return acc.concat([current]); } else { return acc; } }, []);
Set
const filtered = Array.from(new Set(array.map(a => a.id))) .map(id => { return array.find(a => a.id === id) })

Run results for: Filtering duplicates

Set + filter

Reduce

Set