Source/bindings/v8/V8AdaptorFunction.h

/*
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#ifndef V8AdaptorFunction_h
#define V8AdaptorFunction_h

#include "bindings/v8/V8Binding.h"
#include "bindings/v8/V8HiddenPropertyName.h"
#include "bindings/v8/WrapperTypeInfo.h"
#include "wtf/PassRefPtr.h"

namespace WebCore {

//
// FIXME(https://bugs.webkit.org/show_bug.cgi?id=108138):
// V8AdaptorFunction class and V8WrapAsFunction IDL attribute are needed for two reasons:
// - 1) V8 doesn't allow expanding the internal field of function objects. https://code.google.com/p/v8/issues/detail?id=837
//      WebKit need it to associate each wrapper to its backing C++ object. We store it in a hidden property of the wrapped object.
// - 2) Binding codebase assumes every wrapper object is created through ObjectTemplate::NewInstance(), not FunctionTemplate::GetFunction().
// Once 1) is addresssed, we could attack 2) with it. 
//
class V8AdaptorFunction {
public:
    static WrapperTypeInfo info;
    static v8::Handle<v8::Object> unwrap(v8::Handle<v8::Function>);
    static v8::Handle<v8::Function> wrap(v8::Handle<v8::Object>, const AtomicString& name, v8::Isolate*);
    static v8::Handle<v8::Function> get(v8::Handle<v8::Object>);

    static v8::Persistent<v8::FunctionTemplate> getTemplate(v8::Isolate*, WrapperWorldType);
    static v8::Persistent<v8::FunctionTemplate> configureTemplate(v8::Persistent<v8::FunctionTemplate>);
    static v8::Handle<v8::Value> invocationCallback(const v8::Arguments&);
};

inline v8::Handle<v8::Object> V8AdaptorFunction::unwrap(v8::Handle<v8::Function> function)
{
    v8::Handle<v8::Value> wrapped = function->GetHiddenValue(V8HiddenPropertyName::adaptorFunctionPeer());
    ASSERT(!wrapped.IsEmpty());
    ASSERT(wrapped->IsObject());
    return v8::Handle<v8::Object>::Cast(wrapped);
}

inline v8::Handle<v8::Function> V8AdaptorFunction::get(v8::Handle<v8::Object> object)
{
    v8::Handle<v8::Value> adaptorFunction = object->GetHiddenValue(V8HiddenPropertyName::adaptorFunctionPeer());
    ASSERT(!adaptorFunction.IsEmpty());
    ASSERT(adaptorFunction->IsFunction());
    return v8::Handle<v8::Function>::Cast(adaptorFunction);
}

} // namespace WebCore

#endif // V8AdaptorFunction_h