michael@0: /*
michael@0:  * Don't throw a type error if the trap reports an undefined property as
michael@0:  * non-present, regardless of extensibility.
michael@0:  */
michael@0: var target = {};
michael@0: Object.preventExtensions(target);
michael@0: assertEq(
michael@0:     'foo' in new Proxy(target, {
michael@0:         has: function (target, name) {
michael@0:             return false;
michael@0:         }
michael@0:     }), false);