test/webkit/function-prototype-descriptor.js

// Copyright 2013 the V8 project authors. All rights reserved.
// Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
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description(
'Test for function.prototype\'s property descriptor.'
);

function test(func)
{
    // test function.prototype has the correct attributes - writable, enumerable, non-configurable.
    descriptor = Object.getOwnPropertyDescriptor(func, 'prototype');
    shouldBeTrue("descriptor['writable']");
    shouldBeFalse("descriptor['enumerable']");
    shouldBeFalse("descriptor['configurable']");
}

// Test prototype's attributes are correct.
function a() {}
test(a);

// Test prototype's attributes are correct, if assigned without first having being accessed.
function b() {}
b.prototype = {};
test(b);

// Given that prototype is non-configurable, defineProperty should not be able to assign a getter to it.
function c() {}
shouldThrow("Object.defineProperty(c, 'prototype', { get: function(){} })");
test(c);