Source/WebCore/rendering/RenderListItem.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003-2018 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */

 #include "config.h"
 #include "RenderListItem.h"

 #include "CSSFontSelector.h"
 #include "ElementInlines.h"
 #include "ElementTraversal.h"
 #include "HTMLNames.h"
 #include "HTMLOListElement.h"
 #include "HTMLUListElement.h"
 #include "PseudoElement.h"
 #include "RenderStyleConstants.h"
 #include "RenderTreeBuilder.h"
 #include "RenderView.h"
 #include "StyleInheritedData.h"
 #include "UnicodeBidi.h"
 #include <wtf/IsoMallocInlines.h>
 #include <wtf/StackStats.h>
 #include <wtf/StdLibExtras.h>

 namespace WebCore {

 using namespace HTMLNames;

 WTF_MAKE_ISO_ALLOCATED_IMPL(RenderListItem);

 RenderListItem::RenderListItem(Element& element, RenderStyle&& style)
     : RenderBlockFlow(element, WTFMove(style))
 {
     setInline(false);
 }

 RenderListItem::~RenderListItem()
 {
     // Do not add any code here. Add it to willBeDestroyed() instead.
     ASSERT(!m_marker);
 }

 RenderStyle RenderListItem::computeMarkerStyle() const
 {
     if (!is<PseudoElement>(element())) {
         if (auto markerStyle = getCachedPseudoStyle(PseudoId::Marker, &style()))
             return RenderStyle::clone(*markerStyle);
     }

     // The marker always inherits from the list item, regardless of where it might end
     // up (e.g., in some deeply nested line box). See CSS3 spec.
     auto markerStyle = RenderStyle::create();
     markerStyle.inheritFrom(style());

     // In the case of a ::before or ::after pseudo-element, we manually apply the properties
     // otherwise set in the user-agent stylesheet since we don't support ::before::marker or
     // ::after::marker. See bugs.webkit.org/b/218897.
     auto fontDescription = style().fontDescription();
     fontDescription.setVariantNumericSpacing(FontVariantNumericSpacing::TabularNumbers);
     markerStyle.setFontDescription(WTFMove(fontDescription));
     markerStyle.fontCascade().update(&document().fontSelector());
     markerStyle.setUnicodeBidi(UnicodeBidi::Isolate);
     markerStyle.setWhiteSpace(WhiteSpace::Pre);
     markerStyle.setTextTransform(TextTransform::None);
     return markerStyle;
 }

 void RenderListItem::insertedIntoTree(IsInternalMove isInternalMove)
 {
     RenderBlockFlow::insertedIntoTree(isInternalMove);

     if (isInternalMove == IsInternalMove::No)
         updateListMarkerNumbers();
 }

 void RenderListItem::willBeRemovedFromTree(IsInternalMove isInternalMove)
 {
     RenderBlockFlow::willBeRemovedFromTree(isInternalMove);

     if (isInternalMove == IsInternalMove::No)
         updateListMarkerNumbers();
 }

 bool isHTMLListElement(const Node& node)
 {
     return is<HTMLUListElement>(node) || is<HTMLOListElement>(node);
 }

 // Returns the enclosing list with respect to the DOM order.
 static Element* enclosingList(const RenderListItem& listItem)
 {
     auto& element = listItem.element();
     auto* parent = is<PseudoElement>(element) ? downcast<PseudoElement>(element).hostElement() : element.parentElement();
     for (auto* ancestor = parent; ancestor; ancestor = ancestor->parentElement()) {
         if (isHTMLListElement(*ancestor))
             return ancestor;
     }

     // If there's no actual list element, then the parent element acts as our
     // list for purposes of determining what other list items should be numbered as
     // part of the same list.
     return parent;
 }

 static RenderListItem* nextListItemHelper(const Element& list, const Element& element)
 {
     auto* current = &element;
     auto advance = [&] {
         if (!current->renderOrDisplayContentsStyle())
             current = ElementTraversal::nextIncludingPseudoSkippingChildren(*current, &list);
         else
             current = ElementTraversal::nextIncludingPseudo(*current, &list);
     };
     advance();
     while (current) {
         auto* renderer = current->renderer();
         if (!is<RenderListItem>(renderer)) {
             advance();
             continue;
         }
         auto& item = downcast<RenderListItem>(*renderer);
         auto* otherList = enclosingList(item);
         if (!otherList) {
             advance();
             continue;
         }

         // This item is part of our current list, so it's what we're looking for.
         if (&list == otherList)
             return &item;

         // We found ourself inside another list; skip the rest of its contents.
         current = ElementTraversal::nextIncludingPseudoSkippingChildren(*current, &list);
     }

     return nullptr;
 }

 static inline RenderListItem* nextListItem(const Element& list, const RenderListItem& item)
 {
     return nextListItemHelper(list, item.element());
 }

 static inline RenderListItem* firstListItem(const Element& list)
 {
     return nextListItemHelper(list, list);
 }

 static RenderListItem* previousListItem(const Element& list, const RenderListItem& item)
 {
     auto* current = &item.element();
     auto advance = [&] {
         current = ElementTraversal::previousIncludingPseudo(*current, &list);
     };
     advance();
     while (current) {
         auto* renderer = current->renderer();
         if (!is<RenderListItem>(renderer)) {
             advance();
             continue;
         }
         auto& item = downcast<RenderListItem>(*renderer);
         auto* otherList = enclosingList(item);
         if (!otherList) {
             advance();
             continue;
         }

         // This item is part of our current list, so we found what we're looking for.
         if (&list == otherList)
             return &item;

         // We found ourself inside another list; skip the rest of its contents by
         // advancing to it. However, since the list itself might be a list item,
         // don't advance past it.
         current = otherList;
     }
     return nullptr;
 }

 void RenderListItem::updateItemValuesForOrderedList(const HTMLOListElement& list)
 {
     for (auto* listItem = firstListItem(list); listItem; listItem = nextListItem(list, *listItem))
         listItem->updateValue();
 }

 unsigned RenderListItem::itemCountForOrderedList(const HTMLOListElement& list)
 {
     unsigned itemCount = 0;
     for (auto* listItem = firstListItem(list); listItem; listItem = nextListItem(list, *listItem))
         ++itemCount;
     return itemCount;
 }

 void RenderListItem::updateValueNow() const
 {
     auto* list = enclosingList(*this);
     auto* orderedList = dynamicDowncast<HTMLOListElement>(list);

     // The start item is either the closest item before this one in the list that already has a value,
     // or the first item in the list if none have before this have values yet.
     auto* startItem = this;
     if (list) {
         auto* item = this;
         while ((item = previousListItem(*list, *item))) {
             startItem = item;
             if (item->m_value)
                 break;
         }
     }

     auto& startValue = startItem->m_value;
     if (!startValue)
         startValue = orderedList ? orderedList->start() : 1;
     int value = *startValue;
     int increment = (orderedList && orderedList->isReversed()) ? -1 : 1;

     for (auto* item = startItem; item != this; ) {
         item = nextListItem(*list, *item);
         item->m_value = (value += increment);
     }
 }

 void RenderListItem::updateValue()
 {
     if (!m_valueWasSetExplicitly) {
         m_value = std::nullopt;
         if (m_marker)
             m_marker->setNeedsLayoutAndPrefWidthsRecalc();
     }
 }

 void RenderListItem::layout()
 {
     StackStats::LayoutCheckPoint layoutCheckPoint;
     ASSERT(needsLayout());

     RenderBlockFlow::layout();
 }

 void RenderListItem::addOverflowFromChildren()
 {
     if (m_marker)
         m_marker->addOverflowFromListMarker();
     RenderBlockFlow::addOverflowFromChildren();
 }

 void RenderListItem::computePreferredLogicalWidths()
 {
     // FIXME: RenderListMarker::updateMargins() mutates margin style which affects preferred widths.
     if (m_marker && m_marker->preferredLogicalWidthsDirty())
         m_marker->updateMarginsAndContent();

     RenderBlockFlow::computePreferredLogicalWidths();
 }

 void RenderListItem::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     if (!logicalHeight() && hasNonVisibleOverflow())
         return;

     RenderBlockFlow::paint(paintInfo, paintOffset);
 }

 StringView RenderListItem::markerTextWithoutSuffix() const
 {
     if (!m_marker)
         return { };
     return m_marker->textWithoutSuffix();
 }

 StringView RenderListItem::markerTextWithSuffix() const
 {
     if (!m_marker)
         return { };
     return m_marker->textWithSuffix();
 }

 void RenderListItem::explicitValueChanged()
 {
     if (m_marker)
         m_marker->setNeedsLayoutAndPrefWidthsRecalc();

     updateValue();
     auto* list = enclosingList(*this);
     if (!list)
         return;
     auto* item = this;
     while ((item = nextListItem(*list, *item)))
         item->updateValue();
 }

 void RenderListItem::setExplicitValue(std::optional<int> value)
 {
     if (!value) {
         if (!m_valueWasSetExplicitly)
             return;
     } else {
         if (m_valueWasSetExplicitly && m_value == value)
             return;
     }
     m_valueWasSetExplicitly = value.has_value();
     m_value = value;
     explicitValueChanged();
 }

 void RenderListItem::updateListMarkerNumbers()
 {
     auto* list = enclosingList(*this);
     if (!list)
         return;

     bool isInReversedOrderedList = false;
     if (is<HTMLOListElement>(*list)) {
         auto& orderedList = downcast<HTMLOListElement>(*list);
         orderedList.itemCountChanged();
         isInReversedOrderedList = orderedList.isReversed();
     }

     // If an item has been marked for update before, we know that all following items have, too.
     // This gives us the opportunity to stop and avoid marking the same nodes again.
     auto* item = this;
     auto subsequentListItem = isInReversedOrderedList ? previousListItem : nextListItem;
     while ((item = subsequentListItem(*list, *item)) && item->m_value)
         item->updateValue();
 }

 bool RenderListItem::isInReversedOrderedList() const
 {
     auto* list = enclosingList(*this);
     return is<HTMLOListElement>(list) && downcast<HTMLOListElement>(*list).isReversed();
 }

 } // namespace WebCore
	/*
	* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
	* (C) 1999 Antti Koivisto (koivisto@kde.org)
	* Copyright (C) 2003-2018 Apple Inc. All rights reserved.
	* Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Library General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Library General Public License for more details.
	*
	* You should have received a copy of the GNU Library General Public License
	* along with this library; see the file COPYING.LIB. If not, write to
	* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*
	*/

	#include "config.h"
	#include "RenderListItem.h"

	#include "CSSFontSelector.h"
	#include "ElementInlines.h"
	#include "ElementTraversal.h"
	#include "HTMLNames.h"
	#include "HTMLOListElement.h"
	#include "HTMLUListElement.h"
	#include "PseudoElement.h"
	#include "RenderStyleConstants.h"
	#include "RenderTreeBuilder.h"
	#include "RenderView.h"
	#include "StyleInheritedData.h"
	#include "UnicodeBidi.h"
	#include <wtf/IsoMallocInlines.h>
	#include <wtf/StackStats.h>
	#include <wtf/StdLibExtras.h>

	namespace WebCore {

	using namespace HTMLNames;

	WTF_MAKE_ISO_ALLOCATED_IMPL(RenderListItem);

	RenderListItem::RenderListItem(Element& element, RenderStyle&& style)
	: RenderBlockFlow(element, WTFMove(style))
	{
	setInline(false);
	}

	RenderListItem::~RenderListItem()
	{
	// Do not add any code here. Add it to willBeDestroyed() instead.
	ASSERT(!m_marker);
	}

	RenderStyle RenderListItem::computeMarkerStyle() const
	{
	if (!is<PseudoElement>(element())) {
	if (auto markerStyle = getCachedPseudoStyle(PseudoId::Marker, &style()))
	return RenderStyle::clone(*markerStyle);
	}

	// The marker always inherits from the list item, regardless of where it might end
	// up (e.g., in some deeply nested line box). See CSS3 spec.
	auto markerStyle = RenderStyle::create();
	markerStyle.inheritFrom(style());

	// In the case of a ::before or ::after pseudo-element, we manually apply the properties
	// otherwise set in the user-agent stylesheet since we don't support ::before::marker or
	// ::after::marker. See bugs.webkit.org/b/218897.
	auto fontDescription = style().fontDescription();
	fontDescription.setVariantNumericSpacing(FontVariantNumericSpacing::TabularNumbers);
	markerStyle.setFontDescription(WTFMove(fontDescription));
	markerStyle.fontCascade().update(&document().fontSelector());
	markerStyle.setUnicodeBidi(UnicodeBidi::Isolate);
	markerStyle.setWhiteSpace(WhiteSpace::Pre);
	markerStyle.setTextTransform(TextTransform::None);
	return markerStyle;
	}

	void RenderListItem::insertedIntoTree(IsInternalMove isInternalMove)
	{
	RenderBlockFlow::insertedIntoTree(isInternalMove);

	if (isInternalMove == IsInternalMove::No)
	updateListMarkerNumbers();
	}

	void RenderListItem::willBeRemovedFromTree(IsInternalMove isInternalMove)
	{
	RenderBlockFlow::willBeRemovedFromTree(isInternalMove);

	if (isInternalMove == IsInternalMove::No)
	updateListMarkerNumbers();
	}

	bool isHTMLListElement(const Node& node)
	{
	return is<HTMLUListElement>(node) \|\| is<HTMLOListElement>(node);
	}

	// Returns the enclosing list with respect to the DOM order.
	static Element* enclosingList(const RenderListItem& listItem)
	{
	auto& element = listItem.element();
	auto* parent = is<PseudoElement>(element) ? downcast<PseudoElement>(element).hostElement() : element.parentElement();
	for (auto* ancestor = parent; ancestor; ancestor = ancestor->parentElement()) {
	if (isHTMLListElement(*ancestor))
	return ancestor;
	}

	// If there's no actual list element, then the parent element acts as our
	// list for purposes of determining what other list items should be numbered as
	// part of the same list.
	return parent;
	}

	static RenderListItem* nextListItemHelper(const Element& list, const Element& element)
	{
	auto* current = &element;
	auto advance = [&] {
	if (!current->renderOrDisplayContentsStyle())
	current = ElementTraversal::nextIncludingPseudoSkippingChildren(*current, &list);
	else
	current = ElementTraversal::nextIncludingPseudo(*current, &list);
	};
	advance();
	while (current) {
	auto* renderer = current->renderer();
	if (!is<RenderListItem>(renderer)) {
	advance();
	continue;
	}
	auto& item = downcast<RenderListItem>(*renderer);
	auto* otherList = enclosingList(item);
	if (!otherList) {
	advance();
	continue;
	}

	// This item is part of our current list, so it's what we're looking for.
	if (&list == otherList)
	return &item;

	// We found ourself inside another list; skip the rest of its contents.
	current = ElementTraversal::nextIncludingPseudoSkippingChildren(*current, &list);
	}

	return nullptr;
	}

	static inline RenderListItem* nextListItem(const Element& list, const RenderListItem& item)
	{
	return nextListItemHelper(list, item.element());
	}

	static inline RenderListItem* firstListItem(const Element& list)
	{
	return nextListItemHelper(list, list);
	}

	static RenderListItem* previousListItem(const Element& list, const RenderListItem& item)
	{
	auto* current = &item.element();
	auto advance = [&] {
	current = ElementTraversal::previousIncludingPseudo(*current, &list);
	};
	advance();
	while (current) {
	auto* renderer = current->renderer();
	if (!is<RenderListItem>(renderer)) {
	advance();
	continue;
	}
	auto& item = downcast<RenderListItem>(*renderer);
	auto* otherList = enclosingList(item);
	if (!otherList) {
	advance();
	continue;
	}

	// This item is part of our current list, so we found what we're looking for.
	if (&list == otherList)
	return &item;

	// We found ourself inside another list; skip the rest of its contents by
	// advancing to it. However, since the list itself might be a list item,
	// don't advance past it.
	current = otherList;
	}
	return nullptr;
	}

	void RenderListItem::updateItemValuesForOrderedList(const HTMLOListElement& list)
	{
	for (auto* listItem = firstListItem(list); listItem; listItem = nextListItem(list, *listItem))
	listItem->updateValue();
	}

	unsigned RenderListItem::itemCountForOrderedList(const HTMLOListElement& list)
	{
	unsigned itemCount = 0;
	for (auto* listItem = firstListItem(list); listItem; listItem = nextListItem(list, *listItem))
	++itemCount;
	return itemCount;
	}

	void RenderListItem::updateValueNow() const
	{
	auto* list = enclosingList(*this);
	auto* orderedList = dynamicDowncast<HTMLOListElement>(list);

	// The start item is either the closest item before this one in the list that already has a value,
	// or the first item in the list if none have before this have values yet.
	auto* startItem = this;
	if (list) {
	auto* item = this;
	while ((item = previousListItem(list, item))) {
	startItem = item;
	if (item->m_value)
	break;
	}
	}

	auto& startValue = startItem->m_value;
	if (!startValue)
	startValue = orderedList ? orderedList->start() : 1;
	int value = *startValue;
	int increment = (orderedList && orderedList->isReversed()) ? -1 : 1;

	for (auto* item = startItem; item != this; ) {
	item = nextListItem(list, item);
	item->m_value = (value += increment);
	}
	}

	void RenderListItem::updateValue()
	{
	if (!m_valueWasSetExplicitly) {
	m_value = std::nullopt;
	if (m_marker)
	m_marker->setNeedsLayoutAndPrefWidthsRecalc();
	}
	}

	void RenderListItem::layout()
	{
	StackStats::LayoutCheckPoint layoutCheckPoint;
	ASSERT(needsLayout());

	RenderBlockFlow::layout();
	}

	void RenderListItem::addOverflowFromChildren()
	{
	if (m_marker)
	m_marker->addOverflowFromListMarker();
	RenderBlockFlow::addOverflowFromChildren();
	}

	void RenderListItem::computePreferredLogicalWidths()
	{
	// FIXME: RenderListMarker::updateMargins() mutates margin style which affects preferred widths.
	if (m_marker && m_marker->preferredLogicalWidthsDirty())
	m_marker->updateMarginsAndContent();

	RenderBlockFlow::computePreferredLogicalWidths();
	}

	void RenderListItem::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
	{
	if (!logicalHeight() && hasNonVisibleOverflow())
	return;

	RenderBlockFlow::paint(paintInfo, paintOffset);
	}

	StringView RenderListItem::markerTextWithoutSuffix() const
	{
	if (!m_marker)
	return { };
	return m_marker->textWithoutSuffix();
	}

	StringView RenderListItem::markerTextWithSuffix() const
	{
	if (!m_marker)
	return { };
	return m_marker->textWithSuffix();
	}

	void RenderListItem::explicitValueChanged()
	{
	if (m_marker)
	m_marker->setNeedsLayoutAndPrefWidthsRecalc();

	updateValue();
	auto* list = enclosingList(*this);
	if (!list)
	return;
	auto* item = this;
	while ((item = nextListItem(list, item)))
	item->updateValue();
	}

	void RenderListItem::setExplicitValue(std::optional<int> value)
	{
	if (!value) {
	if (!m_valueWasSetExplicitly)
	return;
	} else {
	if (m_valueWasSetExplicitly && m_value == value)
	return;
	}
	m_valueWasSetExplicitly = value.has_value();
	m_value = value;
	explicitValueChanged();
	}

	void RenderListItem::updateListMarkerNumbers()
	{
	auto* list = enclosingList(*this);
	if (!list)
	return;

	bool isInReversedOrderedList = false;
	if (is<HTMLOListElement>(*list)) {
	auto& orderedList = downcast<HTMLOListElement>(*list);
	orderedList.itemCountChanged();
	isInReversedOrderedList = orderedList.isReversed();
	}

	// If an item has been marked for update before, we know that all following items have, too.
	// This gives us the opportunity to stop and avoid marking the same nodes again.
	auto* item = this;
	auto subsequentListItem = isInReversedOrderedList ? previousListItem : nextListItem;
	while ((item = subsequentListItem(list, item)) && item->m_value)
	item->updateValue();
	}

	bool RenderListItem::isInReversedOrderedList() const
	{
	auto* list = enclosingList(*this);
	return is<HTMLOListElement>(list) && downcast<HTMLOListElement>(*list).isReversed();
	}

	} // namespace WebCore