Source code
Revision control
Copy as Markdown
Other Tools
/*
* Any copyright is dedicated to the Public Domain.
*/
var gTestfile = 'isPrototypeOf.js';
var BUGNUMBER = 619283;
var summary = "Object.prototype.isPrototypeOf";
print(BUGNUMBER + ": " + summary);
/**************
* BEGIN TEST *
**************/
function expectThrowTypeError(fun)
{
try
{
var r = fun();
throw new Error("didn't throw TypeError, returned " + r);
}
catch (e)
{
assertEq(e instanceof TypeError, true,
"didn't throw TypeError, got: " + e);
}
}
var isPrototypeOf = Object.prototype.isPrototypeOf;
/*
* 1. If V is not an Object, return false.
*/
assertEq(isPrototypeOf(), false);
assertEq(isPrototypeOf(1), false);
assertEq(isPrototypeOf(Number.MAX_VALUE), false);
assertEq(isPrototypeOf(NaN), false);
assertEq(isPrototypeOf(""), false);
assertEq(isPrototypeOf("sesquicentennial"), false);
assertEq(isPrototypeOf(true), false);
assertEq(isPrototypeOf(false), false);
assertEq(isPrototypeOf(0.72), false);
assertEq(isPrototypeOf(undefined), false);
assertEq(isPrototypeOf(null), false);
/*
* 2. Let O be the result of calling ToObject passing the this value as the
* argument.
*/
var protoGlobal = Object.create(this);
expectThrowTypeError(function() { isPrototypeOf.call(null, {}); });
expectThrowTypeError(function() { isPrototypeOf.call(undefined, {}); });
expectThrowTypeError(function() { isPrototypeOf({}); });
expectThrowTypeError(function() { isPrototypeOf.call(null, protoGlobal); });
expectThrowTypeError(function() { isPrototypeOf.call(undefined, protoGlobal); });
expectThrowTypeError(function() { isPrototypeOf(protoGlobal); });
/*
* 3. Repeat
*/
/*
* 3a. Let V be the value of the [[Prototype]] internal property of V.
* 3b. If V is null, return false.
*/
assertEq(Object.prototype.isPrototypeOf(Object.prototype), false);
assertEq(String.prototype.isPrototypeOf({}), false);
assertEq(Object.prototype.isPrototypeOf(Object.create(null)), false);
/* 3c. If O and V refer to the same object, return true. */
assertEq(Object.prototype.isPrototypeOf({}), true);
assertEq(this.isPrototypeOf(protoGlobal), true);
assertEq(Object.prototype.isPrototypeOf({}), true);
assertEq(Object.prototype.isPrototypeOf(new Number(17)), true);
assertEq(Object.prototype.isPrototypeOf(function(){}), true);
/******************************************************************************/
if (typeof reportCompare === "function")
reportCompare(true, true);
print("All tests passed!");