MeasureThat.net

Run results for: lodash uniqBy vs custom uniqBy

the custom uniqBy doesn't rely on sorting. Instead it creates an object with the already added values

Go to the benchmark
Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36
Chrome 103
Mac OS X 10.15.7
Desktop
2 years ago
Test name Executions per second
lodash 3288946.2 Ops/sec
javascript 5109225.0 Ops/sec
HTML Preparation code:
AخA
 
1
<script>https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.core.js</script>
Script Preparation code:
 
var data = [{a: 1}, {a: 2}, {a: 3}, {a: 4}, {a: 5}, {a: 6}, {a: 7}, {a: 8}, {a: 1}];
Tests:

  • lodash

     
    _.uniqBy(data, 'a');

  • javascript

    ​x
     
    const uniqueBy = (array, fieldName) => {
        const uniqueArr = [];
        const addedFields = {};
    ​
        array.forEach((el) => {
            if (addedFields[fieldName]) {
                return;
            }
            addedFields[el[fieldName]] = true;
            uniqueArr.push(el);
        })
        return uniqueArr;
    }
    uniqueBy(data, 'a')