C++ ContainerNode::treeScope方法代码示例

ALWAYS_INLINE void SelectorDataList::executeFastPathForIdSelector(const ContainerNode& rootNode, const SelectorData& selectorData, const CSSSelector* idSelector, typename SelectorQueryTrait::OutputType& output) const
{
    ASSERT(m_selectors.size() == 1);
    ASSERT(idSelector);

    const AtomicString& idToMatch = idSelector->value();
    if (UNLIKELY(rootNode.treeScope().containsMultipleElementsWithId(idToMatch))) {
        const Vector<Element*>* elements = rootNode.treeScope().getAllElementsById(idToMatch);
        ASSERT(elements);
        size_t count = elements->size();
        bool rootNodeIsTreeScopeRoot = isTreeScopeRoot(rootNode);
        for (size_t i = 0; i < count; ++i) {
            Element& element = *elements->at(i);
            if ((rootNodeIsTreeScopeRoot || element.isDescendantOf(&rootNode)) && selectorMatches(selectorData, element, rootNode)) {
                SelectorQueryTrait::appendOutputForElement(output, &element);
                if (SelectorQueryTrait::shouldOnlyMatchFirstElement)
                    return;
            }
        }
        return;
    }

    Element* element = rootNode.treeScope().getElementById(idToMatch);
    if (!element || !(isTreeScopeRoot(rootNode) || element->isDescendantOf(&rootNode)))
        return;
    if (selectorMatches(selectorData, *element, rootNode))
        SelectorQueryTrait::appendOutputForElement(output, element);
}

void SelectorDataList::execute(ContainerNode& rootNode, typename SelectorQueryTrait::OutputType& output) const
{
    if (!canUseFastQuery(rootNode)) {
        if (m_needsUpdatedDistribution)
            rootNode.updateDistribution();
        if (m_crossesTreeBoundary) {
            executeSlowTraversingShadowTree<SelectorQueryTrait>(rootNode, output);
        } else {
            executeSlow<SelectorQueryTrait>(rootNode, output);
        }
        return;
    }

    ASSERT(m_selectors.size() == 1);

    const CSSSelector& selector = *m_selectors[0];
    const CSSSelector& firstSelector = selector;

    // Fast path for querySelector*('#id'), querySelector*('tag#id').
    if (const CSSSelector* idSelector = selectorForIdLookup(firstSelector)) {
        const AtomicString& idToMatch = idSelector->value();
        if (rootNode.treeScope().containsMultipleElementsWithId(idToMatch)) {
            const WillBeHeapVector<RawPtrWillBeMember<Element>>& elements = rootNode.treeScope().getAllElementsById(idToMatch);
            size_t count = elements.size();
            for (size_t i = 0; i < count; ++i) {
                Element& element = *elements[i];
                if (!(isTreeScopeRoot(rootNode) || element.isDescendantOf(&rootNode)))
                    continue;
                if (selectorMatches(selector, element, rootNode)) {
                    SelectorQueryTrait::appendElement(output, element);
                    if (SelectorQueryTrait::shouldOnlyMatchFirstElement)
                        return;
                }
            }
            return;
        }
        Element* element = rootNode.treeScope().getElementById(idToMatch);
        if (!element || !(isTreeScopeRoot(rootNode) || element->isDescendantOf(&rootNode)))
            return;
        if (selectorMatches(selector, *element, rootNode))
            SelectorQueryTrait::appendElement(output, *element);
        return;
    }

    if (!firstSelector.tagHistory()) {
        // Fast path for querySelector*('.foo'), and querySelector*('div').
        switch (firstSelector.match()) {
        case CSSSelector::Class:
            collectElementsByClassName<SelectorQueryTrait>(rootNode, firstSelector.value(), output);
            return;
        case CSSSelector::Tag:
            collectElementsByTagName<SelectorQueryTrait>(rootNode, firstSelector.tagQName(), output);
            return;
        default:
            break; // If we need another fast path, add here.
        }
    }

    findTraverseRootsAndExecute<SelectorQueryTrait>(rootNode, output);
}

void SelectorDataList::execute(ContainerNode& rootNode, typename SelectorQueryTrait::OutputType& output) const
{
    if (!canUseFastQuery(rootNode)) {
        executeSlow<SelectorQueryTrait>(rootNode, output);
        return;
    }

    ASSERT(m_selectors.size() == 1);

    const SelectorData& selector = m_selectors[0];
    const CSSSelector& firstSelector = selector.selector;

    // Fast path for querySelector*('#id'), querySelector*('tag#id').
    if (const CSSSelector* idSelector = selectorForIdLookup(firstSelector)) {
        const AtomicString& idToMatch = idSelector->value();
        Element* singleMatchingElement = 0;
        if (rootNode.treeScope().getNumberOfElementsWithId(idToMatch, singleMatchingElement) > 1) {
            const Vector<Element*>& elements = rootNode.treeScope().getAllElementsById(idToMatch);
            size_t count = elements.size();
            for (size_t i = 0; i < count; ++i) {
                Element& element = *elements[i];
                if (!(isTreeScopeRoot(rootNode) || element.isDescendantOf(&rootNode)))
                    continue;
                if (selectorMatches(selector, element, rootNode)) {
                    SelectorQueryTrait::appendElement(output, element);
                    if (SelectorQueryTrait::shouldOnlyMatchFirstElement)
                        return;
                }
            }
            return;
        }

        if (!singleMatchingElement || !(isTreeScopeRoot(rootNode) || singleMatchingElement->isDescendantOf(&rootNode)))
            return;
        if (selectorMatches(selector, *singleMatchingElement, rootNode))
            SelectorQueryTrait::appendElement(output, *singleMatchingElement);
        return;
    }

    if (!firstSelector.tagHistory()) {
        // Fast path for querySelector*('.foo'), and querySelector*('div').
        switch (firstSelector.m_match) {
        case CSSSelector::Class:
            collectElementsByClassName<SelectorQueryTrait>(rootNode, firstSelector.value(), output);
            return;
        case CSSSelector::Tag:
            collectElementsByTagName<SelectorQueryTrait>(rootNode, firstSelector.tagQName(), output);
            return;
        default:
            break; // If we need another fast path, add here.
        }
    }

    findTraverseRootsAndExecute<SelectorQueryTrait>(rootNode, output);
}

void SelectorDataList::findTraverseRootsAndExecute(ContainerNode& rootNode, typename SelectorQueryTrait::OutputType& output) const
{
    // We need to return the matches in document order. To use id lookup while there is possiblity of multiple matches
    // we would need to sort the results. For now, just traverse the document in that case.
    ASSERT(m_selectors.size() == 1);

    bool isRightmostSelector = true;
    bool startFromParent = false;

    for (const CSSSelector* selector = m_selectors[0]; selector; selector = selector->tagHistory()) {
        if (selector->match() == CSSSelector::Id && !rootNode.document().containsMultipleElementsWithId(selector->value())) {
            Element* element = rootNode.treeScope().getElementById(selector->value());
            ContainerNode* adjustedNode = &rootNode;
            if (element && (isTreeScopeRoot(rootNode) || element->isDescendantOf(&rootNode)))
                adjustedNode = element;
            else if (!element || isRightmostSelector)
                adjustedNode = 0;
            if (isRightmostSelector) {
                executeForTraverseRoot<SelectorQueryTrait>(*m_selectors[0], adjustedNode, MatchesTraverseRoots, rootNode, output);
                return;
            }

            if (startFromParent && adjustedNode)
                adjustedNode = adjustedNode->parentNode();

            executeForTraverseRoot<SelectorQueryTrait>(*m_selectors[0], adjustedNode, DoesNotMatchTraverseRoots, rootNode, output);
            return;
        }

        // If we have both CSSSelector::Id and CSSSelector::Class at the same time, we should use Id
        // to find traverse root.
        if (!SelectorQueryTrait::shouldOnlyMatchFirstElement && !startFromParent && selector->match() == CSSSelector::Class) {
            if (isRightmostSelector) {
                ClassElementList<AllElements> traverseRoots(rootNode, selector->value());
                executeForTraverseRoots<SelectorQueryTrait>(*m_selectors[0], traverseRoots, MatchesTraverseRoots, rootNode, output);
                return;
            }
            // Since there exists some ancestor element which has the class name, we need to see all children of rootNode.
            if (ancestorHasClassName(rootNode, selector->value())) {
                executeForTraverseRoot<SelectorQueryTrait>(*m_selectors[0], &rootNode, DoesNotMatchTraverseRoots, rootNode, output);
                return;
            }

            ClassElementList<OnlyRoots> traverseRoots(rootNode, selector->value());
            executeForTraverseRoots<SelectorQueryTrait>(*m_selectors[0], traverseRoots, DoesNotMatchTraverseRoots, rootNode, output);
            return;
        }

        if (selector->relation() == CSSSelector::SubSelector)
            continue;
        isRightmostSelector = false;
        if (selector->relation() == CSSSelector::DirectAdjacent || selector->relation() == CSSSelector::IndirectAdjacent)
            startFromParent = true;
        else
            startFromParent = false;
    }

    executeForTraverseRoot<SelectorQueryTrait>(*m_selectors[0], &rootNode, DoesNotMatchTraverseRoots, rootNode, output);
}

void StyleElement::clearDocumentData(Document& document, Element* element)
{
    if (m_sheet)
        m_sheet->clearOwnerNode();

    if (element->inDocument()) {
        ContainerNode* scopingNode = isHTMLStyleElement(element) ? toHTMLStyleElement(element)->scopingNode() :  0;
        TreeScope& treeScope = scopingNode ? scopingNode->treeScope() : element->treeScope();
        document.styleEngine()->removeStyleSheetCandidateNode(element, scopingNode, treeScope);
    }
}

HTMLSlotElement::InsertionNotificationRequest HTMLSlotElement::insertedInto(ContainerNode& insertionPoint)
{
    auto insertionResult = HTMLElement::insertedInto(insertionPoint);
    ASSERT_UNUSED(insertionResult, insertionResult == InsertionDone);

    // This function could be called when this element's shadow root's host or its ancestor is inserted.
    // This element is new to the shadow tree (and its tree scope) only if the parent into which this element
    // or its ancestor is inserted belongs to the same tree scope as this element's.
    if (insertionPoint.isInShadowTree() && isInShadowTree() && &insertionPoint.treeScope() == &treeScope()) {
        if (auto shadowRoot = containingShadowRoot())
            shadowRoot->addSlotElementByName(attributeWithoutSynchronization(nameAttr), *this);
    }

    return InsertionDone;
}

Node* HTMLCollection::namedItem(const AtomicString& name) const
{
    // http://msdn.microsoft.com/workshop/author/dhtml/reference/methods/nameditem.asp
    // This method first searches for an object with a matching id
    // attribute. If a match is not found, the method then searches for an
    // object with a matching name attribute, but only on those elements
    // that are allowed a name attribute.

    ContainerNode* root = rootContainerNode();
    if (name.isEmpty() || !root)
        return 0;

    if (!overridesItemAfter() && root->isInTreeScope()) {
        TreeScope* treeScope = root->treeScope();
        Element* candidate = 0;
        if (treeScope->hasElementWithId(name.impl())) {
            if (!treeScope->containsMultipleElementsWithId(name))
                candidate = treeScope->getElementById(name);
        } else if (treeScope->hasElementWithName(name.impl())) {
            if (!treeScope->containsMultipleElementsWithName(name)) {
                candidate = treeScope->getElementByName(name);
                if (candidate && type() == DocAll && (!candidate->isHTMLElement() || !nameShouldBeVisibleInDocumentAll(toHTMLElement(candidate))))
                    candidate = 0;
            }
        } else
            return 0;

        if (candidate
            && isMatchingElement(this, candidate)
            && (shouldOnlyIncludeDirectChildren() ? candidate->parentNode() == root : candidate->isDescendantOf(root)))
            return candidate;
    }

    // The pathological case. We need to walk the entire subtree.
    updateNameCache();

    if (Vector<Element*>* idResults = idCache(name)) {
        if (idResults->size())
            return idResults->at(0);
    }

    if (Vector<Element*>* nameResults = nameCache(name)) {
        if (nameResults->size())
            return nameResults->at(0);
    }

    return 0;
}