Emit better error message about writable properties

test/webkit/fast/js/Object-defineProperty-expected.txt

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1.  Redistributions of source code must retain the above copyright
 #     notice, this list of conditions and the following disclaimer.
 # 2.  Redistributions in binary form must reproduce the above copyright
 #     notice, this list of conditions and the following disclaimer in the
@@ skipping 27 matching lines @@
 PASS JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], 'foo', {value:1, configurable: true}), 'foo')) is JSON.stringify({value: 1, writable: false, enumerable: false, configurable: true})
 PASS Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], '1', {value:'foo', configurable: true}), '1').value is 'foo'
 PASS a=[1,2,3], Object.defineProperty(a, '1', {value:'foo', configurable: true}), a[1] is 'foo'
 PASS Object.getOwnPropertyDescriptor(Object.defineProperty([1,2,3], '1', {get:getter, configurable: true}), '1').get is getter
 PASS Object.defineProperty([1,2,3], '1', {get:getter, configurable: true})[1] threw exception called getter.
 PASS Object.defineProperty() threw exception TypeError: Object.defineProperty called on non-object.
 PASS Object.defineProperty(null) threw exception TypeError: Object.defineProperty called on non-object.
 PASS Object.defineProperty('foo') threw exception TypeError: Object.defineProperty called on non-object.
 PASS Object.defineProperty({}) threw exception TypeError: Property description must be an object: undefined.
 PASS Object.defineProperty({}, 'foo') threw exception TypeError: Property description must be an object: undefined.
-PASS Object.defineProperty({}, 'foo', {get:undefined, value:true}).foo threw exception TypeError: Invalid property.  A property cannot both have accessors and be writable or have a value, #<Object>.
+PASS Object.defineProperty({}, 'foo', {get:undefined, value:true}).foo threw exception TypeError: Invalid property descriptor. Cannot both specify accessors and a value or writable attribute, #<Object>.
 PASS Object.defineProperty({get foo() { return true; } }, 'foo', {configurable:false}).foo is true
 PASS Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {configurable: true}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {writable: true}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(createUnconfigurableProperty({}, 'foo'), 'foo', {enumerable: true}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(createUnconfigurableProperty({}, 'foo', false, true), 'foo', {enumerable: false}), 'foo' threw exception TypeError: Cannot redefine property: foo.
 PASS JSON.stringify(Object.getOwnPropertyDescriptor(Object.defineProperty(createUnconfigurableProperty({}, 'foo', true), 'foo', {writable: false}), 'foo')) is JSON.stringify({value: 1, writable: false, enumerable: false, configurable: false})
-PASS Object.defineProperty({}, 'foo', {value:1, get: function(){}}) threw exception TypeError: Invalid property.  A property cannot both have accessors and be writable or have a value, #<Object>.
-PASS Object.defineProperty({}, 'foo', {value:1, set: function(){}}) threw exception TypeError: Invalid property.  A property cannot both have accessors and be writable or have a value, #<Object>.
-PASS Object.defineProperty({}, 'foo', {writable:true, get: function(){}}) threw exception TypeError: Invalid property.  A property cannot both have accessors and be writable or have a value, #<Object>.
-PASS Object.defineProperty({}, 'foo', {writable:true, set: function(){}}) threw exception TypeError: Invalid property.  A property cannot both have accessors and be writable or have a value, #<Object>.
+PASS Object.defineProperty({}, 'foo', {value:1, get: function(){}}) threw exception TypeError: Invalid property descriptor. Cannot both specify accessors and a value or writable attribute, #<Object>.
+PASS Object.defineProperty({}, 'foo', {value:1, set: function(){}}) threw exception TypeError: Invalid property descriptor. Cannot both specify accessors and a value or writable attribute, #<Object>.
+PASS Object.defineProperty({}, 'foo', {writable:true, get: function(){}}) threw exception TypeError: Invalid property descriptor. Cannot both specify accessors and a value or writable attribute, #<Object>.
+PASS Object.defineProperty({}, 'foo', {writable:true, set: function(){}}) threw exception TypeError: Invalid property descriptor. Cannot both specify accessors and a value or writable attribute, #<Object>.
 PASS Object.defineProperty({}, 'foo', {get: null}) threw exception TypeError: Getter must be a function: null.
 PASS Object.defineProperty({}, 'foo', {set: null}) threw exception TypeError: Setter must be a function: null.
 PASS Object.defineProperty({}, 'foo', {set: setter}).foo='test' threw exception called setter.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {set: setter1}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {get: getter1}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter}), 'foo', {value: 1}) threw exception TypeError: Cannot redefine property: foo.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {set: setter1}).foo='test' threw exception called setter1.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {get: getter1}).foo threw exception called getter1.
 PASS Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {value: true}).foo is true
 PASS 'foo' in Object.defineProperty(Object.defineProperty({}, 'foo', {set: setter, configurable: true}), 'foo', {writable: true}) is true
@@ skipping 98 matching lines @@
 PASS anObj.slot5 is 123
 PASS anObj._Slot5 is 123
 PASS Object.getOwnPropertyDescriptor(anObj, 'slot5') is undefined.
 PASS anObj.slot5 is 456
 PASS anObj._Slot5 is 123
 PASS Object.getOwnPropertyDescriptor(anObj, 'slot5').value is 456
 PASS successfullyParsed is true
 
 TEST COMPLETE