| description("This test makes sure we don't hang when setting cyclic prototype values: http://bugs.webkit.org/show_bug.cgi?id=6985") |
| |
| var o1 = { p1: 1 }; |
| var o2 = { p2: 2 }; |
| o2.__proto__ = o1; |
| var o3 = { p3: 3 }; |
| o3.__proto__ = o2; |
| |
| // Try to create a cyclical prototype chain. |
| shouldThrow("o1.__proto__ = o3;"); |
| shouldThrow("Object.setPrototypeOf(o1, o3)"); |
| |
| // This changes __proto__ setter behaviour, since __proto__ is an accessor on Object.prototype. |
| o1.__proto__ = null; |
| shouldBeFalse("({}).hasOwnProperty.call(o1, '__proto__')"); |
| o1.__proto__ = o3; |
| shouldBeTrue("({}).hasOwnProperty.call(o1, '__proto__')"); |
| shouldBe("Object.getPrototypeOf(o1)", "null"); |
| |
| // But setPrototypeOf will still work, and will still detect the cycle. |
| shouldThrow("Object.setPrototypeOf(o1, o3)"); |
