V8PopStateEventCustom.cpp   [plain text]

/*
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#include "config.h"
#include "V8PopStateEvent.h"

#include "History.h"
#include "PopStateEvent.h"
#include "SerializedScriptValue.h"
#include "V8HiddenPropertyName.h"
#include "V8History.h"
#include "V8Proxy.h"

namespace WebCore {

// Save the state value to a hidden attribute in the V8PopStateEvent, and return it, for convenience.
static v8::Handle<v8::Value> cacheState(v8::Handle<v8::Object> popStateEvent, v8::Handle<v8::Value> state)
{
    popStateEvent->SetHiddenValue(V8HiddenPropertyName::state(), state);
    return state;
}

v8::Handle<v8::Value> V8PopStateEvent::stateAccessorGetter(v8::Local<v8::String> name, const v8::AccessorInfo& info)
{
    INC_STATS("DOM.PopStateEvent.state");

    v8::Handle<v8::Value> result = info.Holder()->GetHiddenValue(V8HiddenPropertyName::state());

    if (!result.IsEmpty())
        return result;

    PopStateEvent* event = V8PopStateEvent::toNative(info.Holder());
    if (!event->state().hasNoValue())
        return cacheState(info.Holder(), event->state().v8Value());

    History* history = event->history();
    if (!history || !event->serializedState())
        return cacheState(info.Holder(), v8::Null());

    // There's no cached value from a previous invocation, nor a state value was provided by the
    // event, but there is a history object, so first we need to see if the state object has been
    // deserialized through the history object already.
    // The current history state object might've changed in the meantime, so we need to take care
    // of using the correct one, and always share the same deserialization with history.state.

    bool isSameState = history->isSameAsCurrentState(event->serializedState());

    if (isSameState) {
        v8::Handle<v8::Object> v8History = toV8(history, info.GetIsolate()).As<v8::Object>();
        if (!history->stateChanged()) {
            result = v8History->GetHiddenValue(V8HiddenPropertyName::state());
            if (!result.IsEmpty())
                return cacheState(info.Holder(), result);
        }
        result = event->serializedState()->deserialize(0, info.GetIsolate());
        v8History->SetHiddenValue(V8HiddenPropertyName::state(), result);
    } else
        result = event->serializedState()->deserialize(0, info.GetIsolate());

    return cacheState(info.Holder(), result);
}

} // namespace WebCore