object.getprototypeof

object.getprototypeof

An ES5 mostly-spec-compliant Object.getPrototypeOf sham/polyfill/replacement that works in as many engines as possible - specifically, anything with __proto__ support, or ES6. Built-in types will also work correctly in older engines.

This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the spec.

Example

var getPrototypeOf = require('object.getprototypeof');
var assert = require('assert');

assert.equal(getPrototypeOf(true), Boolean.prototype);
assert.equal(getPrototypeOf(42), Number.prototype);
assert.equal(getPrototypeOf(''), String.prototype);
assert.equal(getPrototypeOf(/a/g), RegExp.prototype);
assert.equal(getPrototypeOf(new Date()), Date.prototype);
assert.equal(getPrototypeOf(function () {}), Function.prototype);
assert.equal(getPrototypeOf([]), Array.prototype);
assert.equal(getPrototypeOf({}), Object.prototype);

var getPrototypeOf = require('object.getprototypeof');
var assert = require('assert');
/* when Object.getPrototypeOf is not present */
delete Object.getPrototypeOf;
var shimmed = getPrototypeOf.shim();
assert.equal(shimmed, getPrototypeOf.getPolyfill());

assert.equal(Object.getPrototypeOf(true), Boolean.prototype);
assert.equal(Object.getPrototypeOf(42), Number.prototype);
assert.equal(Object.getPrototypeOf(''), String.prototype);
assert.equal(Object.getPrototypeOf(/a/g), RegExp.prototype);
assert.equal(Object.getPrototypeOf(new Date()), Date.prototype);
assert.equal(Object.getPrototypeOf(function () {}), Function.prototype);
assert.equal(Object.getPrototypeOf([]), Array.prototype);
assert.equal(Object.getPrototypeOf({}), Object.prototype);

var getPrototypeOf = require('object.getprototypeof');
var assert = require('assert');
/* when Object.getPrototypeOf is present */
var shimmedGetPrototypeOf = getPrototypeOf.shim();
assert.equal(shimmedGetPrototypeOf, Object.getPrototypeOf);
assert.equal(Object.getPrototypeOf([]), Array.prototype);

Tests

Simply clone the repo, npm install, and run npm test

Changelog

v1.0.7 - 2025-01-02

Commits

• [actions] split out node 10-20, and 20+ 66e0766
• [Tests] remove unused ESM tests 038e9c6
• [Refactor] use get-proto directly 675ecee
• [Dev Deps] update @es-shims/api, @ljharb/eslint-config, auto-changelog, tape d606eaa
• [Deps] update call-bind, reflect.getprototypeof 004d807
• [Tests] replace aud with npm audit 67b494b
• [Dev Deps] add missing dev dep 1993c8d
• [Dev Deps] add missing peer dep bfe72fa