Get information about original function from bound function

src/api.cc

 // Copyright 2012 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 4287 matching lines @@
 
 
 int Function::ScriptId() const {
   i::Handle<i::JSFunction> func = Utils::OpenHandle(this);
   if (!func->shared()->script()->IsScript()) return v8::Script::kNoScriptId;
   i::Handle<i::Script> script(i::Script::cast(func->shared()->script()));
   return script->id()->value();
 }
 
 
+Local<v8::Value> Function::GetBoundFunction() const {
+  i::Handle<i::JSFunction> func = Utils::OpenHandle(this);
+  if (!func->shared()->bound()) {
+    return v8::Undefined(reinterpret_cast<v8::Isolate*>(func->GetIsolate()));
+  }
+  i::Handle<i::FixedArray> bound_args = i::Handle<i::FixedArray>(
+      i::FixedArray::cast(func->function_bindings()));
+  i::Handle<i::Object> original(
+      bound_args->get(i::JSFunction::kBoundFunctionIndex),
+      func->GetIsolate());
+  return Utils::ToLocal(i::Handle<i::JSFunction>::cast(original));
+}
+
+
 int String::Length() const {
   i::Handle<i::String> str = Utils::OpenHandle(this);
   return str->length();
 }
 
 
 bool String::IsOneByte() const {
   i::Handle<i::String> str = Utils::OpenHandle(this);
   return str->HasOnlyOneByteChars();
 }
@@ skipping 3453 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal