Added checks for ES5 features

lib/class.js

@@ -22,6 +22,12 @@
  * @package core
  */
 
+// whether getters/setters are supported
+var getset = ( Object.prototype.__defineGetter__ === undefined )
+    ? false
+    : true
+;
+
 
 /**
  * Default class implementation
@@ -52,8 +58,8 @@ var prop_copy = function( props, dest )
         // care about methods - properties will simply have their values
         // overwritten)
         var pre    = dest[ property ],
-            getter = props.__lookupGetter__( property ),
+            getter = ( ( getset ) ? props.__lookupGetter__( property ) : null ),
-            setter = props.__lookupSetter__( property );
+            setter = ( ( getset ) ? props.__lookupSetter__( property ) : null );
 
         // check for getter/setter overrides
         if ( getter || setter )
@@ -166,15 +172,26 @@ var attach_extend = function( func )
      *
      * @return  {Object}  extended class
      */
-    Object.defineProperty( func, 'extend',
+    var ext_method = function( props )
-    {
-        value: function( props )
     {
         return extend( this, props );
-        },
+    };
+
+    // if defineProperty is unsupported, do it the old fashioned way (it's just
+    // less restrictive)
+    if ( Object.defineProperty === undefined )
+    {
+        func.extend = ext_method;
+    }
+    else
+    {
+        Object.defineProperty( func, 'extend',
+        {
+            value: ext_method,
 
             enumerable:   false,
             writable:     false,
             configurable: false,
         } );
+    }
 }

test/test-class-gettersetter.js

@@ -22,6 +22,12 @@
  * @package test
  */
 
+// don't perform these tests if getters/setters are unsupported
+if ( Object.prototype.__defineGetter__ === undefined )
+{
+    return;
+}
+
 require( './common' );
 
 var assert = require( 'assert' ),