JSTests/test262/test/built-ins/Object/prototype/isPrototypeOf/builtin.js

// Copyright (C) 2009 the Sputnik authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.

/*---
esid: sec-object.prototype.isprototypeof
description: >
  Tests that Object.prototype.isPrototypeOf meets the requirements
  for built-in objects defined by the introduction of chapter 17 of
  the ECMAScript Language Specification.
features: [Reflect.construct]
---*/

assert(
  Object.isExtensible(Object.prototype.isPrototypeOf),
  'Object.isExtensible(Object.prototype.isPrototypeOf) must return true'
);
assert.sameValue(
  Object.prototype.toString.call(Object.prototype.isPrototypeOf),
  "[object Function]",
  'Object.prototype.toString.call(Object.prototype.isPrototypeOf) must return "[object Function]"'
);
assert.sameValue(
  Object.getPrototypeOf(Object.prototype.isPrototypeOf),
  Function.prototype,
  'Object.getPrototypeOf(Object.prototype.isPrototypeOf) must return the value of Function.prototype'
);
assert.sameValue(
  Object.prototype.isPrototypeOf.hasOwnProperty("prototype"),
  false,
  'Object.prototype.isPrototypeOf.hasOwnProperty("prototype") must return false'
);