Source/WebCore/dom/PseudoElement.cpp

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 * Copyright (C) 2017 Apple Inc. All rights reserved.
 *
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#include "config.h"
#include "PseudoElement.h"

#include "DocumentPage.h"
#include "InspectorInstrumentation.h"
#include "KeyframeEffectStack.h"
#include "RenderElement.h"
#include "RenderImage.h"
#include "RenderQuote.h"
#include "RenderStyle+GettersInlines.h"
#include "StylableInlines.h"
#include "StyleResolver.h"
#include <wtf/TZoneMallocInlines.h>

namespace WebCore {

WTF_MAKE_TZONE_ALLOCATED_IMPL(PseudoElement);

const QualifiedName& pseudoElementTagName()
{
    static NeverDestroyed<QualifiedName> name(nullAtom(), "<pseudo>"_s, nullAtom());
    return name;
}

PseudoElement::PseudoElement(Element& host, PseudoElementType pseudoElementType)
    : Element(pseudoElementTagName(), host.document(), { TypeFlag::IsPseudoElementOrSpecialInternalNode })
    , m_hostElement(host)
    , m_pseudoElementType(pseudoElementType)
{
    setEventTargetFlag(EventTargetFlag::IsConnected);
    ASSERT(pseudoElementType == PseudoElementType::Before || pseudoElementType == PseudoElementType::After);
}

PseudoElement::~PseudoElement()
{
    ASSERT(!m_hostElement);
}

Ref<PseudoElement> PseudoElement::create(Element& host, PseudoElementType pseudoElementType)
{
    Ref pseudoElement = adoptRef(*new PseudoElement(host, pseudoElementType));

    InspectorInstrumentation::pseudoElementCreated(host.document().protectedPage().get(), pseudoElement.get());

    return pseudoElement;
}

void PseudoElement::clearHostElement()
{
    InspectorInstrumentation::pseudoElementDestroyed(document().protectedPage().get(), *this);

    Styleable::fromElement(*this).elementWasRemoved();

    m_hostElement = nullptr;
}

bool PseudoElement::rendererIsNeeded(const RenderStyle& style)
{
    if (pseudoElementRendererIsNeeded(&style))
        return true;

    if (RefPtr element = m_hostElement.get()) {
        if (auto* stack = element->keyframeEffectStack(Style::PseudoElementIdentifier { pseudoElementType() }))
            return stack->requiresPseudoElement();
    }
    return false;
}

} // namespace