make it possible for any script object to serve as activation object

This was possible in the old back-end. In JSC, activation objects
have to be instances of JSC::JSVariableObject. So the way we solve
it is by having our QScriptActivationObject be able to act as a
proxy to any other JSObject.

3 files changed, 98 insertions, 11 deletions

diff --git a/src/script/api/qscriptcontext.cpp b/src/script/api/qscriptcontext.cpp
index 1b69ac1..4a78f7c 100644
--- a/src/script/api/qscriptcontext.cpp
+++ b/src/script/api/qscriptcontext.cpp
@@ -461,6 +461,13 @@ QScriptValue QScriptContext::activationObject() const
             result = new (frame)JSC::JSActivation(frame, body);
         }*/
     }
+
+    if (result && result->isObject(&QScript::QScriptActivationObject::info)
+        && (static_cast<QScript::QScriptActivationObject*>(result)->delegate() != 0)) {
+        // Return the object that property access is being delegated to
+        result = static_cast<QScript::QScriptActivationObject*>(result)->delegate();
+    }
+
     return QScript::scriptEngineFromExec(frame)->scriptValueFromJSCValue(result);
 }
 
@@ -485,15 +492,16 @@ void QScriptContext::setActivationObject(const QScriptValue &activation)
     JSC::JSObject *object = JSC::asObject(engine->scriptValueToJSCValue(activation));
     if (object == engine->originalGlobalObjectProxy)
         object = engine->originalGlobalObject();
-    if (!object->isVariableObject()) {
-        qWarning("QScriptContext::setActivationObject() failed: not an activation object");
-        return;
-    }
 
     uint flags = QScriptEnginePrivate::contextFlags(frame);
     if ((flags & QScriptEnginePrivate::NativeContext) && !(flags & QScriptEnginePrivate::HasScopeContext)) {
         //For native functions, we create a scope node
-        frame->setScopeChain(frame->scopeChain()->copy()->push(object));
+        JSC::JSObject *scope = object;
+        if (!scope->isVariableObject()) {
+            // Create a QScriptActivationObject that acts as a proxy
+            scope = new (frame) QScript::QScriptActivationObject(frame, scope);
+        }
+        frame->setScopeChain(frame->scopeChain()->copy()->push(scope));
         QScriptEnginePrivate::setContextFlags(frame, flags | QScriptEnginePrivate::HasScopeContext);
         return;
     }
@@ -502,7 +510,16 @@ void QScriptContext::setActivationObject(const QScriptValue &activation)
     JSC::ScopeChainNode *node = frame->scopeChain();
     while (node != 0) {
         if (node->object && node->object->isVariableObject()) {
-            node->object = object;
+            if (!object->isVariableObject()) {
+                if (node->object->isObject(&QScript::QScriptActivationObject::info)) {
+                    static_cast<QScript::QScriptActivationObject*>(node->object)->setDelegate(object);
+                } else {
+                    // Create a QScriptActivationObject that acts as a proxy
+                    node->object = new (frame) QScript::QScriptActivationObject(frame, object);
+                }
+            } else {
+                node->object = object;
+            }
             break;
         }
         node = node->next;
diff --git a/src/script/bridge/qscriptactivationobject.cpp b/src/script/bridge/qscriptactivationobject.cpp
index ae466e8..5faf7fe 100644
--- a/src/script/bridge/qscriptactivationobject.cpp
+++ b/src/script/bridge/qscriptactivationobject.cpp
@@ -63,8 +63,9 @@ namespace QScript
 
 const JSC::ClassInfo QScriptActivationObject::info = { "QScriptActivationObject", 0, 0, 0 };
 
-QScriptActivationObject::QScriptActivationObject(JSC::ExecState *callFrame)
-    : JSC::JSVariableObject(callFrame->globalData().activationStructure, new QScriptActivationObjectData(callFrame->registers()))
+QScriptActivationObject::QScriptActivationObject(JSC::ExecState *callFrame, JSC::JSObject *delegate)
+    : JSC::JSVariableObject(callFrame->globalData().activationStructure,
+                            new QScriptActivationObjectData(callFrame->registers(), delegate))
 {
 }
 
@@ -73,8 +74,36 @@ QScriptActivationObject::~QScriptActivationObject()
     delete d;
 }
 
+bool QScriptActivationObject::getOwnPropertySlot(JSC::ExecState* exec, const JSC::Identifier& propertyName, JSC::PropertySlot& slot)
+{
+    if (d_ptr()->delegate != 0)
+        return d_ptr()->delegate->getOwnPropertySlot(exec, propertyName, slot);
+    return JSC::JSVariableObject::getOwnPropertySlot(exec, propertyName, slot);
+}
+
+bool QScriptActivationObject::getPropertyAttributes(JSC::ExecState* exec, const JSC::Identifier& propertyName, unsigned& attributes) const
+{
+    if (d_ptr()->delegate != 0)
+        return d_ptr()->delegate->getPropertyAttributes(exec, propertyName, attributes);
+    return JSC::JSVariableObject::getPropertyAttributes(exec, propertyName, attributes);
+}
+
+void QScriptActivationObject::getPropertyNames(JSC::ExecState* exec, JSC::PropertyNameArray& propertyNames, unsigned listedAttributes)
+{
+    if (d_ptr()->delegate != 0) {
+        d_ptr()->delegate->getPropertyNames(exec, propertyNames, listedAttributes);
+        return;
+    }
+    return JSC::JSVariableObject::getPropertyNames(exec, propertyNames, listedAttributes);
+}
+
 void QScriptActivationObject::putWithAttributes(JSC::ExecState *exec, const JSC::Identifier &propertyName, JSC::JSValue value, unsigned attributes)
 {
+    if (d_ptr()->delegate != 0) {
+        d_ptr()->delegate->putWithAttributes(exec, propertyName, value, attributes);
+        return;
+    }
+
     if (symbolTablePutWithAttributes(propertyName, value, attributes))
         return;
     
@@ -82,6 +111,31 @@ void QScriptActivationObject::putWithAttributes(JSC::ExecState *exec, const JSC:
     JSObject::putWithAttributes(exec, propertyName, value, attributes, true, slot);
 }
 
+void QScriptActivationObject::put(JSC::ExecState* exec, const JSC::Identifier& propertyName, JSC::JSValue value, JSC::PutPropertySlot& slot)
+{
+    if (d_ptr()->delegate != 0) {
+        d_ptr()->delegate->put(exec, propertyName, value, slot);
+        return;
+    }
+    JSC::JSVariableObject::put(exec, propertyName, value, slot);
+}
+
+void QScriptActivationObject::put(JSC::ExecState* exec, unsigned propertyName, JSC::JSValue value)
+{
+    if (d_ptr()->delegate != 0) {
+        d_ptr()->delegate->put(exec, propertyName, value);
+        return;
+    }
+    JSC::JSVariableObject::put(exec, propertyName, value);
+}
+
+bool QScriptActivationObject::deleteProperty(JSC::ExecState* exec, const JSC::Identifier& propertyName, bool checkDontDelete)
+{
+    if (d_ptr()->delegate != 0)
+        return d_ptr()->delegate->deleteProperty(exec, propertyName, checkDontDelete);
+    return JSC::JSVariableObject::deleteProperty(exec, propertyName, checkDontDelete);
+}
+
 } // namespace QScript
 
 QT_END_NAMESPACE
diff --git a/src/script/bridge/qscriptactivationobject_p.h b/src/script/bridge/qscriptactivationobject_p.h
index 8c62b23..fd7b0be 100644
--- a/src/script/bridge/qscriptactivationobject_p.h
+++ b/src/script/bridge/qscriptactivationobject_p.h
@@ -64,21 +64,37 @@ namespace QScript
 
 class QScriptActivationObject : public JSC::JSVariableObject {
 public:
-    QScriptActivationObject(JSC::ExecState *callFrame);
+    QScriptActivationObject(JSC::ExecState *callFrame, JSC::JSObject *delegate = 0);
     virtual ~QScriptActivationObject();
     virtual bool isDynamicScope() const { return true; }
+
+    virtual bool getOwnPropertySlot(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::PropertySlot&);
+    virtual bool getPropertyAttributes(JSC::ExecState*, const JSC::Identifier&, unsigned&) const;
+    virtual void getPropertyNames(JSC::ExecState*, JSC::PropertyNameArray&, unsigned listedAttributes = JSC::Structure::Prototype);
+
     virtual void putWithAttributes(JSC::ExecState *exec, const JSC::Identifier &propertyName, JSC::JSValue value, unsigned attributes);
+    virtual void put(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::JSValue value, JSC::PutPropertySlot&);
+    virtual void put(JSC::ExecState*, unsigned propertyName, JSC::JSValue value);
+
+    virtual bool deleteProperty(JSC::ExecState*, const JSC::Identifier& propertyName, bool checkDontDelete = true);
 
     virtual const JSC::ClassInfo* classInfo() const { return &info; }
     static const JSC::ClassInfo info;
 
     struct QScriptActivationObjectData : public JSVariableObjectData {
-        QScriptActivationObjectData(JSC::Register* registers)
-            : JSVariableObjectData(&symbolTable, registers)
+        QScriptActivationObjectData(JSC::Register* registers, JSC::JSObject *dlg)
+            : JSVariableObjectData(&symbolTable, registers),
+              delegate(dlg)
         { }
         JSC::SymbolTable symbolTable;
+        JSC::JSObject *delegate;
     };
 
+    JSC::JSObject *delegate() const
+    { return d_ptr()->delegate; }
+    void setDelegate(JSC::JSObject *delegate)
+    { d_ptr()->delegate = delegate; }
+
     QScriptActivationObjectData *d_ptr() const { return static_cast<QScriptActivationObjectData *>(d); }
 };