michael@0: load(libdir + "asserts.js");
michael@0: 
michael@0: /*
michael@0:  * Throw a TypeError if the current descriptor is a data descriptor and the
michael@0:  * descriptor returned by the trap is not, or vice versa, and the current
michael@0:  * descriptor is non-configurable
michael@0:  */
michael@0: var target = {};
michael@0: Object.defineProperty(target, 'foo', {
michael@0:     value: 'bar',
michael@0:     configurable: false
michael@0: });
michael@0: var caught = false;
michael@0: assertThrowsInstanceOf(function () { 
michael@0:     Object.getOwnPropertyDescriptor(new Proxy(target, {
michael@0:         getOwnPropertyDescriptor: function (target, name) {
michael@0:             return {
michael@0:                 get: function () {
michael@0:                     return 'bar';
michael@0:                 },
michael@0:                 configurable: false
michael@0:             };
michael@0:         }
michael@0:     }), 'foo');
michael@0: }, TypeError);
michael@0: 
michael@0: var target = {};
michael@0: Object.defineProperty(target, 'foo', {
michael@0:     value: function () {
michael@0:         return 'bar';
michael@0:     },
michael@0:     configurable: false
michael@0: });
michael@0: assertThrowsInstanceOf(function () { 
michael@0:     Object.getOwnPropertyDescriptor(new Proxy(target, {
michael@0:         getOwnPropertyDescriptor: function (target, name) {
michael@0:             return {
michael@0:                 value: 'bar',
michael@0:                 configurable: false
michael@0:             };
michael@0:         }
michael@0:     }), 'foo');
michael@0: }, TypeError);