Run results for: lodash mapValues vs vanilla Object.keys foreach vs lodash reduce

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

vanilla object.keys

21K/s

lodash mapValues

20K/s

lodash reduce

2K/s

View exact numbers

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var obj = {}
for (let i = 0; i < 1000; ++i) {
    obj[`a${i}`] = i;
}
var transform = (n) => n * n + 1;

Tests:

lodash mapValues
const newObj = _.mapValues(obj, (v, k) => transform(v));
vanilla object.keys
const newObj = {}; Object.keys(obj).forEach((key) => { newObj[key] = transform(obj[key]); });
lodash reduce
const newObj = _.reduce(obj, (acc, val, key) => { acc[key] = transform(val); return acc; })