Run results for: Lodash keyBy vs JS Map (with small and large size)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/111.0

Browser: Firefox 111

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Lodash keyBy	584.4 Ops/sec
JS Map	824.0 Ops/sec

Script Preparation code:

window.data = [];
for (let i = 0; i < 10000; i++) {
    data.push({
        key: `key${i}`
    });
}

window.dataBig = [];
for (let i = 0; i < 100000; i++) {
    dataBig.push({
        key: `key${i}`
    });
}

Tests:

Lodash keyBy (10k entries)
const keyed = _.keyBy(data, v => v.key)
JS Map (10k entries)
const map = new Map(); for (let i = 0; i < data.length; i++) { map.set(data[i].key, data[i]); }
Lodash keyBy (100k entries)
const keyed = _.keyBy(dataBig, v => v.key)
JS Map (100k entries)
const map = new Map(); for (let i = 0; i < dataBig.length; i++) { map.set(dataBig[i].key, dataBig[i]); }

Run results for: Lodash keyBy vs JS Map (with small and large size)

Lodash keyBy (10k entries)

JS Map (10k entries)

Lodash keyBy (100k entries)

JS Map (100k entries)