core-js/internals/object-get-prototype-of.js

Standard library

// 19.1.2.9 / 15.2.3.2 Object.getPrototypeOf(O)
var has = require('../internals/has');
var toObject = require('../internals/to-object');
var IE_PROTO = require('../internals/shared-key')('IE_PROTO');
var CORRECT_PROTOTYPE_GETTER = require('../internals/correct-prototype-getter');
var ObjectPrototype = Object.prototype;

module.exports = CORRECT_PROTOTYPE_GETTER ? Object.getPrototypeOf : function (O) {
  O = toObject(O);
  if (has(O, IE_PROTO)) return O[IE_PROTO];
  if (typeof O.constructor == 'function' && O instanceof O.constructor) {
    return O.constructor.prototype;
  } return O instanceof Object ? ObjectPrototype : null;
};