Run results for: Spread vs Object.assign vs Object.keys with forEach deep clone

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36

Browser: Chrome 117

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Using the spread operator	19153344.0 Ops/sec
Using Object.assign	10854715.0 Ops/sec
forEach	1855195.9 Ops/sec
deep clone	377658.8 Ops/sec

Script Preparation code:

var firstObject = {
  "name": "John Doe",
  "age": 30,
  "isStudent": false,
  "address": {
    "street": "123 Main St",
    "city": "Anytown",
    "zipcode": "12345"
  },
  "contacts": [
    {
      "type": "email",
      "value": "john.doe@example.com"
    },
    {
      "type": "phone",
      "value": "+1 123-456-7890"
    }
  ],
  "skills": {
    "programming": ["JavaScript", "Python", "Java"],
    "design": ["Photoshop", "Illustrator"],
    "languages": {
      "spoken": ["English", "Spanish"],
      "written": ["English", "French"]
    }
  },
  "isActive": true,
  "projects": [
    {
      "name": "Project A",
      "status": "completed",
      "team": ["Alice", "Bob"]
    },
    {
      "name": "Project B",
      "status": "in progress",
      "team": ["Charlie", "David"]
    }
  ]
}

Tests:

Using the spread operator
const finalObject = {...firstObject};
Using Object.assign
const finalObject = Object.assign(firstObject);
forEach
const finalObject = {} Object.keys(firstObject).forEach(key => {finalObject[key] = firstObject[key] })
deep clone
function deepClone(original) { const cloned = {}; Object.keys(original).forEach(key => { const value = original[key]; if (typeof value === 'object' && value !== null) { // Recursively clone nested objects cloned[key] = deepClone(value); } else { // Copy non-object values directly cloned[key] = value; } }); return cloned; } const finalObject = deepClone(firstObject);

Run results for: Spread vs Object.assign vs Object.keys with forEach deep clone

Using the spread operator

Using Object.assign

forEach

deep clone