Index: src/org/mozilla/javascript/ScriptableObject.java
===================================================================
RCS file: /cvsroot/mozilla/js/rhino/src/org/mozilla/javascript/ScriptableObject.java,v
retrieving revision 1.125
diff -u -r1.125 ScriptableObject.java
--- src/org/mozilla/javascript/ScriptableObject.java	18 Jul 2007 15:09:25 -0000	1.125
+++ src/org/mozilla/javascript/ScriptableObject.java	14 Jan 2008 13:24:32 -0000
@@ -149,6 +149,12 @@
     private static final int SLOT_MODIFY_GETTER_SETTER = 4;
     private static final int SLOT_MODIFY_CONST = 5;
 
+    // Used to indicate a failed MOP call.
+    private static final Object MOP_CALL_FAILED = new Object();
+    
+    // Guards to protect against infinite recursion with __metaobject__.get.
+    boolean disableMop = false;
+
     private static class Slot implements Serializable
     {
         static final long serialVersionUID = -3539051633409902634L;
@@ -240,6 +246,60 @@
      * method.
      */
     public abstract String getClassName();
+    
+    /**
+     * Gets the metaobject for the specified object.
+     */
+    protected ScriptableObject getMetaobject(Scriptable object)
+    {
+        if (this.has("__metaobject__", object, null))
+        {
+            Object o = this.get("__metaobject__", object, null);
+            if (o instanceof ScriptableObject)
+            {
+                ScriptableObject metaobject = (ScriptableObject) o;
+                //We want to disable MOP for the metaobject itself
+                metaobject.put("__metaobject__", metaobject, null);
+                
+                return metaobject;
+            }
+        }
+        return null;
+    }
+    
+    /**
+     * Call the function on the specified metaobject, if the function
+     * is specified by the metaobject.
+     * 
+     * @param metaobject  Metaobject which may have the function.
+     * @param metafunction  Function name to call.
+     * @param start  Scope of the metaobject, used to disable the metaobject.
+     * @param args  Arguments to pass to the function.
+     * 
+     * @return  Result of the call, or MOP_CALL_FAILED.
+     */
+    protected Object callMetafunction(ScriptableObject metaobject, String metafunction,
+            Scriptable start, Object[] args)
+    {
+        Object value = MOP_CALL_FAILED;
+        if (metaobject.has(metafunction, metaobject, null))
+        {
+            try
+            {
+                start.put("__metaobject__", start, null);
+                Context cx = Context.getCurrentContext();
+                Callable f = ScriptRuntime.getNameFunctionAndThis(metafunction, cx, metaobject);
+                Scriptable thisObj = ScriptRuntime.lastStoredScriptable(cx);
+                
+                value = f.call(cx, start, thisObj, args);
+            }
+            finally
+            {
+                start.put("__metaobject__", start, metaobject);
+            }
+        }
+        return value;
+    }
 
     /**
      * Returns true if the named property is defined.
@@ -248,10 +308,30 @@
      * @param start the object in which the lookup began
      * @return true if and only if the property was found in the object
      */
-    public boolean has(String name, Scriptable start)
+    public boolean has(String name, Scriptable start, Object flag)
     {
         return null != getSlot(name, 0, SLOT_QUERY);
     }
+    
+    /**
+     *  This looks for a metaobject, specified by the __metaobject__ property.
+     *  If one is found, __metaobject__.has(thisObj,property) will be called.
+     *   
+     *  @see org.mozilla.javascript.Scriptable#has(java.lang.String, org.mozilla.javascript.Scriptable)
+     */
+    public boolean has(String name, Scriptable start) {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = name;
+            
+            Object value = this.callMetafunction(metaobject, "has", start, args);
+            if (value != MOP_CALL_FAILED) return ScriptRuntime.toBoolean(value);
+        }
+        return this.has(name, start, null);
+    }
 
     /**
      * Returns true if the property index is defined.
@@ -260,10 +340,28 @@
      * @param start the object in which the lookup began
      * @return true if and only if the property was found in the object
      */
-    public boolean has(int index, Scriptable start)
+    public boolean has(int index, Scriptable start, Object flag)
     {
         return null != getSlot(null, index, SLOT_QUERY);
     }
+    
+    /**
+     * Looks for __metaobject__.has.  If not found, works normally.
+     * @see org.mozilla.javascript.Scriptable#has(int, org.mozilla.javascript.Scriptable)
+     */
+    public boolean has(int index, Scriptable start) {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = new Integer(index);
+            
+            Object value = this.callMetafunction(metaobject, "has", start, args);
+            if (value != MOP_CALL_FAILED) return ScriptRuntime.toBoolean(value);
+        }
+        return this.has(index, start, null);
+    }
 
     /**
      * Returns the value of the named property or NOT_FOUND.
@@ -275,10 +373,36 @@
      * @param start the object in which the lookup began
      * @return the value of the property (may be null), or NOT_FOUND
      */
-    public Object get(String name, Scriptable start)
+    public Object get(String name, Scriptable start, Object flag)
     {
         return getImpl(name, 0, start);
     }
+    
+    /**
+     * This checks for the existence of a __metaobject__ property with a get method.
+     * Otherwise, this method will work normally.
+     * 
+     * @see org.mozilla.javascript.Scriptable#get(java.lang.String, org.mozilla.javascript.Scriptable)
+     */
+    public Object get(String name, Scriptable start)
+    {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null && !this.disableMop)// && !name.equals(lastPropCalled))
+        {
+            //lastPropCalled = name;
+            this.disableMop = true;
+            
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = name;
+            
+            Object value = this.callMetafunction(metaobject, "get", start, args);
+            //lastPropCalled = null;
+            this.disableMop = false;
+            if (value != MOP_CALL_FAILED) return value;
+        }
+        return this.get(name, start, null);
+    }
 
     /**
      * Returns the value of the indexed property or NOT_FOUND.
@@ -287,10 +411,34 @@
      * @param start the object in which the lookup began
      * @return the value of the property (may be null), or NOT_FOUND
      */
-    public Object get(int index, Scriptable start)
+    public Object get(int index, Scriptable start, Object flag)
     {
         return getImpl(null, index, start);
     }
+    
+    /**
+     * This checks for the existence of a __metaobject__ property with a get method.
+     * Otherwise, this method will work normally.
+     * @see org.mozilla.javascript.Scriptable#get(int, org.mozilla.javascript.Scriptable)
+     */
+    public Object get(int index, Scriptable start) {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null && !this.disableMop)//(lastIndexCalled==null || index!=lastIndexCalled.intValue()))
+        {
+            //lastIndexCalled = new Integer(index);
+            this.disableMop = true;
+            
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = new Integer(index);
+            
+            Object value = this.callMetafunction(metaobject, "get", start, args);
+            //lastIndexCalled = null;
+            this.disableMop = false;
+            if (value != MOP_CALL_FAILED) return value;
+        }
+        return this.get(index, start, null);
+    }
 
     /**
      * Sets the value of the named property, creating it if need be.
@@ -307,7 +455,7 @@
      * @param start the object whose property is being set
      * @param value value to set the property to
      */
-    public void put(String name, Scriptable start, Object value)
+    public void put(String name, Scriptable start, Object value, Object flag)
     {
         if (putImpl(name, 0, start, value, EMPTY))
             return;
@@ -315,6 +463,26 @@
         if (start == this) throw Kit.codeBug();
         start.put(name, start, value);
     }
+    
+    /**
+     * Looks for __metaobject__.set.  Otherwise, works normally.
+     * @see org.mozilla.javascript.Scriptable#put(java.lang.String, org.mozilla.javascript.Scriptable, java.lang.Object)
+     */
+    public void put(String name, Scriptable start, Object value)
+    {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null && !name.equals("__metaobject__"))
+        {
+            Object[] args = new Object[3];
+            args[0] = start;
+            args[1] = name;
+            args[2] = value;
+            
+            Object result = this.callMetafunction(metaobject, "set", start, args);
+            if (result != MOP_CALL_FAILED) return;
+        }
+        this.put(name, start, value, null);
+    }
 
     /**
      * Sets the value of the indexed property, creating it if need be.
@@ -323,7 +491,7 @@
      * @param start the object whose property is being set
      * @param value value to set the property to
      */
-    public void put(int index, Scriptable start, Object value)
+    public void put(int index, Scriptable start, Object value, Object flag)
     {
         if (putImpl(null, index, start, value, EMPTY))
             return;
@@ -331,6 +499,26 @@
         if (start == this) throw Kit.codeBug();
         start.put(index, start, value);
     }
+    
+    /**
+     * Looks for __metaobject__.set.  Otherwise, works normally.
+     * @see org.mozilla.javascript.Scriptable#put(int, org.mozilla.javascript.Scriptable, java.lang.Object)
+     */
+    public void put(int index, Scriptable start, Object value)
+    {
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[3];
+            args[0] = start;
+            args[1] = new Integer(index);
+            args[2] = value;
+            
+            Object result = this.callMetafunction(metaobject, "set", start, args);
+            if (result != MOP_CALL_FAILED) return;
+        }
+        this.put(index, start, value, null);
+    }
 
     /**
      * Removes a named property from the object.
@@ -340,11 +528,31 @@
      *
      * @param name the name of the property
      */
-    public void delete(String name)
+    public void delete(String name, Object flag)
     {
         checkNotSealed(name, 0);
         accessSlot(name, 0, SLOT_REMOVE);
     }
+    
+    /**
+     * Looks for __metaobject__.remove().  If not found, works normally.  
+     * @see org.mozilla.javascript.Scriptable#delete(java.lang.String)
+     */
+    public void delete(String name)
+    {
+        Scriptable start = this;
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = name;
+            
+            Object result = this.callMetafunction(metaobject, "remove", start, args);
+            if (result != MOP_CALL_FAILED) return;
+        }
+        this.delete(name, null);
+    }
 
     /**
      * Removes the indexed property from the object.
@@ -354,11 +562,31 @@
      *
      * @param index the numeric index for the property
      */
-    public void delete(int index)
+    public void delete(int index, Object flag)
     {
         checkNotSealed(null, index);
         accessSlot(null, index, SLOT_REMOVE);
     }
+    
+    /**
+     * Looks for __metaobject__.remove().  If not found, works normally.
+     * @see org.mozilla.javascript.Scriptable#delete(int)
+     */
+    public void delete(int index)
+    {
+        Scriptable start = this;
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = new Integer(index);
+            
+            Object result = this.callMetafunction(metaobject, "remove", start, args);
+            if (result != MOP_CALL_FAILED) return;
+        }
+        this.delete(index, null);
+    }
 
     /**
      * Sets the value of the named const property, creating it if need be.
@@ -606,6 +834,7 @@
 
     /**
      * Sets the prototype of the object.
+     * @return 
      */
     public void setPrototype(Scriptable m)
     {
@@ -639,9 +868,44 @@
      * Integer entry in the returned array. Properties accessed by
      * a String will have a String entry in the returned array.
      */
-    public Object[] getIds() {
+    public Object[] getIds(Object flag) {
         return getIds(false);
     }
+    
+    /**
+     * Returns ids for the current object, deferring to
+     * __metaobject__.getIds(thisObj), if that exists. 
+     * @see org.mozilla.javascript.Scriptable#getIds()
+     */
+    public Object[] getIds()
+    {
+        Scriptable start = this;
+        ScriptableObject metaobject = this.getMetaobject(start);
+        
+        if (metaobject != null)
+        {
+            Object[] args = new Object[1];
+            args[0] = start;
+            
+            Object result = this.callMetafunction(metaobject, "getIds", start, args);
+            if (result != MOP_CALL_FAILED) {
+                if (result instanceof NativeArray) {
+                    NativeArray na = (NativeArray) result;
+                    Object[] naIds = na.getIds();
+                    Object[] ids = new Object[naIds.length];
+                    for (int i=0; i<naIds.length; i++) {
+                        ids[i] = na.get(i, na);
+                    }
+                    return ids;
+                }
+                else {
+                    throw new IllegalArgumentException("Did not receive an array of ids.  Got a "
+                            + result.getClass().getName());
+                }
+            }
+        }
+        return getIds(null);
+    }
 
     /**
      * Returns an array of ids for the properties of the object.
@@ -768,13 +1032,28 @@
      * @return true if "this" appears in value's prototype chain
      *
      */
-    public boolean hasInstance(Scriptable instance) {
+    public boolean hasInstance(Scriptable instance, Object flag) {
         // Default for JS objects (other than Function) is to do prototype
         // chasing.  This will be overridden in NativeFunction and non-JS
         // objects.
 
         return ScriptRuntime.jsDelegatesTo(instance, this);
     }
+    
+    public boolean hasInstance(Scriptable instance) {
+        Scriptable start = this;
+        ScriptableObject metaobject = this.getMetaobject(start);
+        if (metaobject != null)
+        {
+            Object[] args = new Object[2];
+            args[0] = start;
+            args[1] = instance;
+            
+            Object value = this.callMetafunction(metaobject, "hasInstanceOf", start, args);
+            if (value != MOP_CALL_FAILED) return ScriptRuntime.toBoolean(value);
+        }
+        return this.hasInstance(instance, null);
+    }
 
     /**
      * Custom <tt>==</tt> operator.
Index: src/org/mozilla/javascript/BaseFunction.java
===================================================================
RCS file: /cvsroot/mozilla/js/rhino/src/org/mozilla/javascript/BaseFunction.java,v
retrieving revision 1.65
diff -u -r1.65 BaseFunction.java
--- src/org/mozilla/javascript/BaseFunction.java	28 Nov 2007 10:15:06 -0000	1.65
+++ src/org/mozilla/javascript/BaseFunction.java	14 Jan 2008 13:24:32 -0000
@@ -88,7 +88,7 @@
      *              value's prototype chain
      *
      */
-    public boolean hasInstance(Scriptable instance)
+    public boolean hasInstance(Scriptable instance, Object flag)
     {
         Object protoProp = ScriptableObject.getProperty(this, "prototype");
         if (protoProp instanceof Scriptable) {