Run results for: Map vs Vanilla For vs For Of 1000

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36

Browser: Chrome 76

Operating system: Windows

Device Platform: Desktop

Date tested: 5 years ago

Script Preparation code:

var objects = new Array(100000);
objects.fill({key: 'derp'});

Tests:

Map with clone
objects.map((obj) => { obj = Object.assign({}, obj); obj.group = 'grouping'; return obj; })
Map
objects.map((obj) => { obj.group = 'grouping'; return obj; })
Vanilla For
for (let i = 0; i < objects.length; i++) { objects[i].group = 'grouping'; }
For Of
for (const obj of objects) { obj.group = 'grouping'; }