Source/core/css/analyzer/DescendantInvalidationSet.cpp

/*
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include "config.h"
#include "core/css/analyzer/DescendantInvalidationSet.h"

#include "core/css/resolver/StyleResolver.h"
#include "core/dom/Element.h"

namespace WebCore {

DescendantInvalidationSet::DescendantInvalidationSet()
    : m_allDescendantsMightBeInvalid(false)
{
}

void DescendantInvalidationSet::combine(const DescendantInvalidationSet& other)
{
    // No longer bother combining data structures, since the whole subtree is deemed invalid.
    if (wholeSubtreeInvalid())
        return;

    if (other.wholeSubtreeInvalid()) {
        setWholeSubtreeInvalid();
        return;
    }

    if (other.m_classes) {
        HashSet<AtomicString>::const_iterator end = other.m_classes->end();
        for (HashSet<AtomicString>::const_iterator it = other.m_classes->begin(); it != end; ++it)
            addClass(*it);
    }

    if (other.m_ids) {
        HashSet<AtomicString>::const_iterator end = other.m_ids->end();
        for (HashSet<AtomicString>::const_iterator it = other.m_ids->begin(); it != end; ++it)
            addId(*it);
    }

    if (other.m_tagNames) {
        HashSet<AtomicString>::const_iterator end = other.m_tagNames->end();
        for (HashSet<AtomicString>::const_iterator it = other.m_tagNames->begin(); it != end; ++it)
            addTagName(*it);
    }
}

HashSet<AtomicString>& DescendantInvalidationSet::ensureClassSet()
{
    if (!m_classes)
        m_classes = adoptPtr(new HashSet<AtomicString>);
    return *m_classes;
}

HashSet<AtomicString>& DescendantInvalidationSet::ensureIdSet()
{
    if (!m_ids)
        m_ids = adoptPtr(new HashSet<AtomicString>);
    return *m_ids;
}

HashSet<AtomicString>& DescendantInvalidationSet::ensureTagNameSet()
{
    if (!m_tagNames)
        m_tagNames = adoptPtr(new HashSet<AtomicString>);
    return *m_tagNames;
}

void DescendantInvalidationSet::addClass(const AtomicString& className)
{
    if (wholeSubtreeInvalid())
        return;
    ensureClassSet().add(className);
}

void DescendantInvalidationSet::addId(const AtomicString& id)
{
    if (wholeSubtreeInvalid())
        return;
    ensureIdSet().add(id);
}

void DescendantInvalidationSet::addTagName(const AtomicString& tagName)
{
    if (wholeSubtreeInvalid())
        return;
    ensureTagNameSet().add(tagName);
}

void DescendantInvalidationSet::getClasses(Vector<AtomicString>& classes) const
{
    if (!m_classes)
        return;
    for (HashSet<AtomicString>::const_iterator it = m_classes->begin(); it != m_classes->end(); ++it)
        classes.append(*it);
}

void DescendantInvalidationSet::setWholeSubtreeInvalid()
{
    if (m_allDescendantsMightBeInvalid)
        return;

    m_allDescendantsMightBeInvalid = true;
    m_classes = nullptr;
    m_ids = nullptr;
    m_tagNames = nullptr;
}

} // namespace WebCore