Source/WebCore/html/EmptyHTMLCollection.h

/*
 * Copyright (C) 2023 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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 with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include <WebCore/CollectionType.h>

namespace WebCore {

class EmptyHTMLCollection;

template<>
struct CollectionClassTraits<EmptyHTMLCollection> {
    static constexpr CollectionType collectionType = CollectionType::DocEmpty;
};

} // namespace WebCore

#include "HTMLCollection.h"

namespace WebCore {

class EmptyHTMLCollection final : public HTMLCollection {
public:
    static Ref<EmptyHTMLCollection> create(Document& document, CollectionType type)
    {
        return adoptRef(*new EmptyHTMLCollection(document, type));
    }

    Element* item(unsigned) const final { return nullptr; };
    Element* namedItem(const AtomString&) const final { return nullptr; };
    unsigned length() const final { return 0; }

private:
    EmptyHTMLCollection(Document& document, CollectionType type)
        : HTMLCollection(document, type)
    { }
};

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_HTMLCOLLECTION(EmptyHTMLCollection)