third_party/WebKit/Source/core/html/HTMLSlotElement.cpp

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#include "core/html/HTMLSlotElement.h"

#include "core/HTMLNames.h"
#include "core/dom/NodeTraversal.h"
#include "core/dom/shadow/InsertionPoint.h"

namespace blink {

using namespace HTMLNames;

inline HTMLSlotElement::HTMLSlotElement(Document& document)
    : HTMLElement(slotTag, document)
{
}

DEFINE_NODE_FACTORY(HTMLSlotElement);

void HTMLSlotElement::appendAssignedNode(Node& node)
{
    m_assignedNodes.append(&node);
}

void HTMLSlotElement::appendDistributedNode(Node& node)
{
    m_distributedNodes.append(&node);
}

void HTMLSlotElement::appendDistributedNodes(const WillBeHeapVector<RefPtrWillBeMember<Node>>& nodes)
{
    m_distributedNodes.appendVector(nodes);
}

void HTMLSlotElement::clearDistribution()
{
    m_assignedNodes.clear();
    m_distributedNodes.clear();
}

Node* HTMLSlotElement::distributedNodeNextTo(const Node& node) const
{
    size_t index = m_distributedNodes.find(&node);
    if (index == kNotFound || index + 1 == m_distributedNodes.size())
        return nullptr;
    return m_distributedNodes[index + 1].get();
}

Node* HTMLSlotElement::distributedNodePreviousTo(const Node& node) const
{
    size_t index = m_distributedNodes.find(&node);
    if (index == kNotFound || index == 0)
        return nullptr;
    return m_distributedNodes[index - 1].get();
}

void HTMLSlotElement::attach(const AttachContext& context)
{
    for (auto& node : m_distributedNodes) {
        if (node->needsAttach())
            node->attach(context);
    }

    HTMLElement::attach(context);
}

void HTMLSlotElement::detach(const AttachContext& context)
{
    for (auto& node : m_distributedNodes)
        node->lazyReattachIfAttached();

    HTMLElement::detach(context);
}

void HTMLSlotElement::updateDistributedNodesWithFallback()
{
    if (!m_distributedNodes.isEmpty())
        return;
    for (auto& child : NodeTraversal::childrenOf(*this)) {
        // Insertion points are not supported as slots fallback
        if (isActiveInsertionPoint(child))
            continue;
        if (isHTMLSlotElement(child))
            appendDistributedNodes(toHTMLSlotElement(child).getDistributedNodes());
        else
            appendDistributedNode(child);
    }
}

DEFINE_TRACE(HTMLSlotElement)
{
    visitor->trace(m_assignedNodes);
    visitor->trace(m_distributedNodes);
    HTMLElement::trace(visitor);
}

}