Source/WebCore/dom/ScopedEventQueue.cpp

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

#include "Event.h"
#include "Node.h"
#include <wtf/NeverDestroyed.h>

namespace WebCore {

ScopedEventQueue& ScopedEventQueue::singleton()
{
    static NeverDestroyed<ScopedEventQueue> scopedEventQueue;
    return scopedEventQueue;
}

void ScopedEventQueue::enqueueEvent(Ref<Event>&& event)
{
    ASSERT(is<Node>(event->target()));
    if (m_scopingLevel)
        m_queuedEvents.append(WTFMove(event));
    else
        dispatchEvent(event);
}

void ScopedEventQueue::dispatchEvent(Event& event) const
{
    downcast<Node>(*event.target()).dispatchEvent(event);
}

void ScopedEventQueue::dispatchAllEvents()
{
    Vector<Ref<Event>> queuedEvents = WTFMove(m_queuedEvents);
    for (auto& queuedEvent : queuedEvents)
        dispatchEvent(queuedEvent);
}

void ScopedEventQueue::incrementScopingLevel()
{
    ++m_scopingLevel;
}

void ScopedEventQueue::decrementScopingLevel()
{
    ASSERT(m_scopingLevel);
    --m_scopingLevel;
    if (!m_scopingLevel)
        dispatchAllEvents();
}

}