API: added function to find instance of template in prototype chain.

src/api.cc

 // Copyright 2009 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 1910 matching lines @@
 
 Local<Value> v8::Object::GetPrototype() {
   ON_BAILOUT("v8::Object::GetPrototype()", return Local<v8::Value>());
   ENTER_V8;
   i::Handle<i::Object> self = Utils::OpenHandle(this);
   i::Handle<i::Object> result = i::GetPrototype(self);
   return Utils::ToLocal(result);
 }
 
 
+Local<Object> v8::Object::FindInstanceInPrototypeChain(
+    v8::Handle<FunctionTemplate> tmpl) {
+  ON_BAILOUT("v8::Object::FindInstanceInPrototypeChain()",
+             return Local<v8::Object>());
+  ENTER_V8;
+  i::JSObject* object = *Utils::OpenHandle(this);
+  i::FunctionTemplateInfo* tmpl_info = *Utils::OpenHandle(*tmpl);
+  while (!object->IsInstanceOf(tmpl_info)) {
+    i::Object* prototype = object->GetPrototype();
+    if (!prototype->IsJSObject()) return Local<Object>();
+    object = i::JSObject::cast(prototype);
+  }
+  return Utils::ToLocal(i::Handle<i::JSObject>(object));
+}
+
+
 Local<Array> v8::Object::GetPropertyNames() {
   ON_BAILOUT("v8::Object::GetPropertyNames()", return Local<v8::Array>());
   ENTER_V8;
   v8::HandleScope scope;
   i::Handle<i::JSObject> self = Utils::OpenHandle(this);
   i::Handle<i::FixedArray> value = i::GetKeysInFixedArrayFor(self);
   // Because we use caching to speed up enumeration it is important
   // to never change the result of the basic enumeration function so
   // we clone the result.
   i::Handle<i::FixedArray> elms = i::Factory::CopyFixedArray(value);
@@ skipping 1678 matching lines @@
       reinterpret_cast<HandleScopeImplementer*>(storage);
   List<void**>* blocks_of_archived_thread = thread_local->Blocks();
   v8::ImplementationUtilities::HandleScopeData* handle_data_of_archived_thread =
       &thread_local->handle_scope_data_;
   Iterate(v, blocks_of_archived_thread, handle_data_of_archived_thread);
 
   return storage + ArchiveSpacePerThread();
 }
 
 } }  // namespace v8::internal