Change Object.defineProperty to accept undefined as getters and setters and t...

src/v8natives.js

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 545 matching lines @@
         (!desc.hasValue() ||
          SameValue(desc.getValue(), current.getValue())) &&
         (!desc.hasGetter() ||
          SameValue(desc.getGet(), current.getGet())) &&
         (!desc.hasSetter() ||
          SameValue(desc.getSet(), current.getSet()))) {
       return true;
     }
 
     // Step 7
-    if (desc.isConfigurable() ||  desc.isEnumerable() != current.isEnumerable())
+    if (desc.isConfigurable() || desc.isEnumerable() != current.isEnumerable())
       throw MakeTypeError("redefine_disallowed", ["defineProperty"]);
     // Step 9
     if (IsDataDescriptor(current) != IsDataDescriptor(desc))
       throw MakeTypeError("redefine_disallowed", ["defineProperty"]);
     // Step 10
     if (IsDataDescriptor(current) && IsDataDescriptor(desc)) {
       if (!current.isWritable() && desc.isWritable())
         throw MakeTypeError("redefine_disallowed", ["defineProperty"]);
       if (!current.isWritable() && desc.hasValue() &&
           !SameValue(desc.getValue(), current.getValue())) {
@@ skipping 39 matching lines @@
       flag |= READ_ONLY;
     }
     var value = void 0;  // Default value is undefined.
     if (desc.hasValue()) {
       value = desc.getValue();
     } else if (!IS_UNDEFINED(current)) {
       value = current.getValue();
     }
     %DefineOrRedefineDataProperty(obj, p, value, flag);
   } else {
-    if (desc.hasGetter() && IS_FUNCTION(desc.getGet())) {
+    if (desc.hasGetter() &&

[Lasse Reichstein, 2010/12/16 09:43:34]

How about putting desc.getGet() in a variable (and ditto for desc.getSet()
below). You are up to two or three uses of it by now.

[Rico, 2010/12/16 12:17:55]

Well, we don't know if desc has a getter, intuitively I would not like to have a
variable with a value that is not there (if you call getGet it will return
undefined even when there is no getter)

+        (IS_FUNCTION(desc.getGet()) || IS_UNDEFINED(desc.getGet()))) {
        %DefineOrRedefineAccessorProperty(obj, p, GETTER, desc.getGet(), flag);
     }
-    if (desc.hasSetter() && IS_FUNCTION(desc.getSet())) {
+    if (desc.hasSetter() &&
+        (IS_FUNCTION(desc.getSet()) || IS_UNDEFINED(desc.getSet()))) {
       %DefineOrRedefineAccessorProperty(obj, p, SETTER, desc.getSet(), flag);
     }
   }
   return true;
 }
 
 
 // ES5 section 15.2.3.2.
 function ObjectGetPrototypeOf(obj) {
   if (!IS_SPEC_OBJECT(obj))
@@ skipping 553 matching lines @@
 // ----------------------------------------------------------------------------
 
 function SetupFunction() {
   InstallFunctions($Function.prototype, DONT_ENUM, $Array(
     "bind", FunctionBind,
     "toString", FunctionToString
   ));
 }
 
 SetupFunction();