Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.97 Safari/537.36
Chrome 96
Mac OS X 10.15.7
Desktop
3 years ago
Test name Executions per second
Object.fromEntries 135.9 Ops/sec
Reduce (reuse object) 991.2 Ops/sec
Reduce (creating temporary objects) 46.0 Ops/sec
Script Preparation code:
AخA
 
var data = { ...Array.from(Array(10000).keys()) };
Tests:
  • Object.fromEntries

     
    Object.fromEntries(Object.entries(data).map((key, value) => [key, value]));
  • Reduce (reuse object)

     
    Object.entries(data).reduce((acc, [k, v]) => {
      acc[k] = v;
      return acc;
    }, {});
  • Reduce (creating temporary objects)

     
    Object.entries(data).reduce((acc, [k, v]) => ({
      ...acc,
      [k]: v
    }), {});