Run results for: lazy getters vs proxy vs property

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36

Browser: Chrome 138

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

lazy2

10.7M/s

lazy1

10.7M/s

property

8.9M/s

proxy

627K/s

View exact numbers

Test name	Executions per second
✓ lazy2	10,723,576 Ops/sec
lazy1	10,691,199 Ops/sec
property	8,863,970 Ops/sec
proxy	627,352 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

function lazy1(prototype, propertyKey, descriptor) {
    const originalFunction = descriptor.get;

    descriptor.get = function() {
        const val = originalFunction.apply(this, arguments);
        Object.defineProperty(this, propertyKey, {
            value: val
        });
        return val;
    }
}

function lazy2(prototype, propertyKey, descriptor) {
    const originalFunction = descriptor.get;
    const cachedKey = `__lazy__${propertyKey}`;

    descriptor.get = function() {
        if (!this.hasOwnProperty(cachedKey)) {
            this[cachedKey] = originalFunction.apply(this, arguments);
        }

        return this[cachedKey];
    };
}

class A {
	constructor(){
    	this.w = 1;
    }
    get x() {
        return 1;
    }
    get y() {
        return 1;
    }
}
lazy1(A.prototype, 'x', Object.getOwnPropertyDescriptor(A.prototype, 'x'));
lazy2(A.prototype, 'y', Object.getOwnPropertyDescriptor(A.prototype, 'y'));
const b = new Proxy({},{get(target, key){return 1;}});
const a = new A();

Tests:

lazy1
let tot = 0; while(tot < 100) tot+=a.x;
lazy2
let tot = 0; while(tot < 100) tot+=a.y;
proxy
let tot = 0; while(tot < 100) tot+=b.z;
property
let tot = 0; while(tot < 100) tot+=a.w;