Run results for: Object.defineProperty vs Object.assign vs Assign to Proxy

Test name	Executions per second
✓ Direct Object Property	108,661 Ops/sec
Object.defineProperty	35,693 Ops/sec
Object.assign (mutable)	33,443 Ops/sec
Object.defineProperty on Proxy	29,657 Ops/sec
Object.defineProperty with getter and setter	28,697 Ops/sec
Object.defineProperty on Proxy with getter and setter	25,074 Ops/sec
Property direct on Proxy	18,161 Ops/sec
Object.defineProperties (plural) with getter and setter	13,649 Ops/sec
Object.assign (immutable)	741 Ops/sec

Script Preparation code:

var input = new Array(100).fill().map((v, i) => i);
var proxyHandlers = {
  get(target, prop, receiver) {
    return Reflect.get(target, prop, receiver);
  },
  set(target, prop, value) {
    return Reflect.set(target, prop, value);
  },
  defineProperty(target, prop, descriptor) {
    return Reflect.defineProperty(target, prop, descriptor);
  },  
};

Tests:

Object.defineProperty
const output = input.reduce((acc, value) => Object.defineProperty(acc, `key${value}`, { value }), {});
Object.assign (immutable)
const output = input.reduce((acc, value) => Object.assign({}, acc, { [`key${value}`]: value }), {});
Object.assign (mutable)
const output = input.reduce((acc, value) => Object.assign(acc, { [`key${value}`]: value }), {});
Object.defineProperty on Proxy
const output = input.reduce((acc, value) => Object.defineProperty(acc, `key${value}`, { value }), new Proxy({}, proxyHandlers));
Property direct on Proxy
const output = input.reduce((acc, value) => { acc[`key${value}`] = value; return acc; }, new Proxy({}, proxyHandlers));
Direct Object Property
const output = input.reduce((acc, value) => { acc[`key${value}`] = value; return acc; }, {});
Object.defineProperty with getter and setter
const output = input.reduce((acc, value) => Object.defineProperty(acc, `key${value}`, { get(){return value}, set(v) {} }), {});
Object.defineProperties (plural) with getter and setter
const output = input.reduce((acc, value) => Object.defineProperties(acc, {[`key${value}`]: { get(){return value}, set(v) {} }}), {});
Object.defineProperty on Proxy with getter and setter
const output = input.reduce((acc, value) => Object.defineProperty(acc, `key${value}`, { get(){return value}, set(v) {} }), new Proxy({}, proxyHandlers));
Object.assign on Proxy (mutable)
const output = input.reduce((acc, value) => Object.assign(acc, { [`key${value}`]: value }), new Proxy({}, proxyHandlers));

Run results for: Object.defineProperty vs Object.assign vs Assign to Proxy

Object.defineProperty

Object.assign (immutable)

Object.assign (mutable)

Object.defineProperty on Proxy

Property direct on Proxy

Direct Object Property

Object.defineProperty with getter and setter

Object.defineProperties (plural) with getter and setter

Object.defineProperty on Proxy with getter and setter

Object.assign on Proxy (mutable)