Run results for: Read property reflect vs getOwnPropertyDescriptor

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.81 Safari/537.36 Edg/94.0.992.50

Browser: Chrome 94

Operating system: Windows

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
t.requiredProp	7558763.5 Ops/sec
getPropertyOrDefault(t)	411337.6 Ops/sec
d.requiredProp	7693993.0 Ops/sec
getPropertyOrDefault(d)	288381.9 Ops/sec

Script Preparation code:

 function getPropertyDescriptor(obj, property) {
     const descriptor = Object.getOwnPropertyDescriptor(obj, property);
     if (descriptor !== undefined)
         return descriptor;
     const proto = Object.getPrototypeOf(obj);
     if (proto === null)
         return undefined;
     return getPropertyDescriptor(proto, property);
 }

 function getPropertyOrDefault(obj, property, defaultValue) {
     const d = getPropertyDescriptor(obj, property);
     if (d) {
         if (Object.prototype.hasOwnProperty.call(d, "value"))
             return d.value;
         if (Object.prototype.hasOwnProperty.call(d, "get"))
             return d.get.call(obj);
     }
     return defaultValue;
 }

 function getPropertyOrDefault2(obj, property, defaultValue) {
   if (Reflect.has(obj, property)) return obj[property];
   return defaultValue;
 }

 class T {
     constructor() {
         this.requiredField = 1;
         this.undefinableField = undefined;
         this.m_requiredProp = 1;
         this.m_undefinableProp = undefined;
     }
     get requiredProp() {
         return this.m_requiredProp;
     }
     set requiredProp(value) {
         this.m_requiredProp = value;
     }
     get undefinableProp() {
         return this.m_undefinableProp;
     }
     set undefinableProp(value) {
         this.m_undefinableProp = value;
     }
 }
 var t = new T();
 t.requiredField = 1;
 t.requiredProp = 1;

 class D extends T {}
 var d = new D();
d.requiredField = 1;
 d.requiredProp = 1;

Tests:

requiredProp
const v = t.requiredProp;
requiredProp_getPropertyOrDefault
const v = getPropertyOrDefault(t, "requiredProp", 0);
derived_requiredProp
const v = d.requiredProp
derived_requiredProp_getPropertyOrDefault
const v = getPropertyOrDefault(d, "requiredProp", 0);
requiredField
const v = t.requiredField
requiredField_getPropertyOrDefault
const v = getPropertyOrDefault(t, "requiredField", 0);
derived_requiredField
const v = d.requiredField
derived_requiredField_getPropertyOrDefault
const v = getPropertyOrDefault(d, "requiredField", 0);
derived_prop_reflectHas
const v = getPropertyOrDefault2(d, "requiredField", 0);

Run results for: Read property reflect vs getOwnPropertyDescriptor

requiredProp

requiredProp_getPropertyOrDefault

derived_requiredProp

derived_requiredProp_getPropertyOrDefault

requiredField

requiredField_getPropertyOrDefault

derived_requiredField

derived_requiredField_getPropertyOrDefault

derived_prop_reflectHas