prop_copy() will now keep track of abstract methods

lib/class.js

@@ -58,10 +58,13 @@ exports.extend = function( base )
  */
 exports.abstractMethod = function( definition )
 {
-    return function()
+    var method = function()
     {
         throw new Error( "Cannot call abstract method" );
-    }
+    };
+
+    method.abstractFlag = true;
+    return method;
 }
 
 
@@ -94,6 +97,11 @@ function prop_copy( props, dest, result_data )
 {
     result_data = result_data || {};
 
+    // initialize result_data
+    result_data = {
+        abstractMethods: [],
+    };
+
     // copy each of the properties to the destination object
     for ( property in props )
     {
@@ -105,6 +113,12 @@ function prop_copy( props, dest, result_data )
             getter = ( ( getset ) ? props.__lookupGetter__( property ) : null ),
             setter = ( ( getset ) ? props.__lookupSetter__( property ) : null );
 
+        // did we find an abstract method?
+        if ( ( prop instanceof Function ) && ( prop.abstractFlag === true ) )
+        {
+            result_data.abstractMethods.push( property );
+        }
+
         // check for getter/setter overrides
         if ( getter || setter )
         {