Run results for: structuredClone vs spread vs Object.assign + more

Note!: none of these tests actually do the same thing, and the data in the example is simple. consider also using arrays: those are nice. Some of these are shallow, some of these are deep-ish. Data is lost through JSON serialization and back, and more data would be lost in JSON and other methods depending on the data stored.

Go to the benchmark

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:135.0) Gecko/20100101 Firefox/135.0

Browser: Firefox 135

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Cursed Proxy

31.4M/s

Object.assign

20.4M/s

spread syntax

6.8M/s

Object.fromEntries

1.5M/s

JSON

1.0M/s

structuredClone()

601K/s

View exact numbers

Test name	Executions per second
✓ Cursed Proxy	31,418,248 Ops/sec
Object.assign	20,394,786 Ops/sec
spread syntax	6,750,126 Ops/sec
Object.fromEntries	1,465,096 Ops/sec
JSON	1,010,684 Ops/sec
structuredClone()	601,000 Ops/sec

Script Preparation code:

var voucher = {
    "single": false,
    "applyOverTaxes": false,
    "discountType": "1",
    "value": 100,
    "minimumAmount": 0,
    "quantity": 1,
    "suffixLength": 8,
    "code": "IF5R0AFX",
    "vertical": true,
    "allowedPaymentMethods": null,
    "allowedBanks": null,
    "types": undefined,
    "partners": "Many",
    "startDate": "2020-10-21T00:00:00.000Z",
    "endDate": "2020-10-21T00:00:00.000Z",
    "applyed": false
}

Tests:

structuredClone()
var newObj = structuredClone(voucher)
spread syntax
var newObj = {...voucher}
Object.assign
var newObj = Object.assign({}, voucher)
Object.fromEntries
var newObj = Object.fromEntries(Object.entries(voucher))
JSON
// loses the "types" property var newObj = JSON.parse(JSON.stringify(voucher))
Cursed Proxy
// this registers as surprisingly performant for some reason, but keep in mind i didn't benchmark // usage, only creation, so in reality this could potentially not be performant when setting/getting. // either way this is really scuffed so you probably shouldn't take this approach var newObject = new Proxy({}, { get (o, p) { return p in o ? o[p] : o[p] ??= voucher[p] }, set (o, p, v) { o[p] = v; return true } })