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/*
* Copyright (C) 2008 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.
* 3. Neither the name of Apple Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE 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 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.
*/
#include "config.h"
#include "AccessibilityList.h"
#include "AXObjectCache.h"
#include "HTMLElement.h"
#include "HTMLNames.h"
#include "ListStyleType.h"
#include "PseudoElement.h"
#include "RenderListItem.h"
#include "RenderStyleInlines.h"
namespace WebCore {
using namespace HTMLNames;
AccessibilityList::AccessibilityList(RenderObject* renderer)
: AccessibilityRenderObject(renderer)
{
}
AccessibilityList::AccessibilityList(Node& node)
: AccessibilityRenderObject(node)
{
}
AccessibilityList::~AccessibilityList() = default;
Ref<AccessibilityList> AccessibilityList::create(RenderObject* renderer)
{
return adoptRef(*new AccessibilityList(renderer));
}
Ref<AccessibilityList> AccessibilityList::create(Node& node)
{
return adoptRef(*new AccessibilityList(node));
}
bool AccessibilityList::computeAccessibilityIsIgnored() const
{
return accessibilityIsIgnoredByDefault();
}
bool AccessibilityList::isUnorderedList() const
{
// The ARIA spec says the "list" role is supposed to mimic a UL or OL tag.
// Since it can't be both, it's probably OK to say that it's an un-ordered list.
// On the Mac, there's no distinction to the client.
if (ariaRoleAttribute() == AccessibilityRole::List)
return true;
auto* node = this->node();
return node && (node->hasTagName(menuTag) || node->hasTagName(ulTag));
}
bool AccessibilityList::isOrderedList() const
{
// ARIA says a directory is like a static table of contents, which sounds like an ordered list.
if (ariaRoleAttribute() == AccessibilityRole::Directory)
return true;
auto* node = this->node();
return node && node->hasTagName(olTag);
}
bool AccessibilityList::isDescriptionList() const
{
auto* node = this->node();
return node && node->hasTagName(dlTag);
}
bool AccessibilityList::childHasPseudoVisibleListItemMarkers(Node* node)
{
// Check if the list item has a pseudo-element that should be accessible (e.g. an image or text)
auto* element = dynamicDowncast<Element>(node);
auto* beforePseudo = element ? element->beforePseudoElement() : nullptr;
if (!beforePseudo)
return false;
RefPtr axBeforePseudo = axObjectCache()->getOrCreate(beforePseudo->renderer());
if (!axBeforePseudo)
return false;
if (!axBeforePseudo->accessibilityIsIgnored())
return true;
for (const auto& child : axBeforePseudo->children()) {
if (!child->accessibilityIsIgnored())
return true;
}
// Platforms which expose rendered text content through the parent element will treat
// those renderers as "ignored" objects.
#if USE(ATSPI)
String text = axBeforePseudo->textUnderElement();
return !text.isEmpty() && !text.containsOnly<isASCIIWhitespace>();
#else
return false;
#endif
}
AccessibilityRole AccessibilityList::determineAccessibilityRole()
{
m_ariaRole = determineAriaRoleAttribute();
// Directory is mapped to list for now, but does not adhere to the same heuristics.
if (ariaRoleAttribute() == AccessibilityRole::Directory)
return AccessibilityRole::List;
// Heuristic to determine if this list is being used for layout or for content.
// 1. If it's a named list, like ol or aria=list, then it's a list.
// 1a. Unless the list has no children, then it's not a list.
// 2. If it displays visible list markers, it's a list.
// 3. If it does not display list markers and has only one child, it's not a list.
// 4. If it does not have any listitem children, it's not a list.
// 5. Otherwise it's a list (for now).
auto role = AccessibilityRole::List;
// Temporarily set role so that we can query children (otherwise canHaveChildren returns false).
m_role = role;
unsigned listItemCount = 0;
bool hasVisibleMarkers = false;
const auto& children = this->children();
// DescriptionLists are always semantically a description list, so do not apply heuristics.
if (isDescriptionList() && children.size())
return AccessibilityRole::DescriptionList;
for (const auto& child : children) {
auto* axChild = dynamicDowncast<AccessibilityObject>(child.get());
if (axChild && axChild->ariaRoleAttribute() == AccessibilityRole::ListItem)
listItemCount++;
else if (child->roleValue() == AccessibilityRole::ListItem) {
// Rendered list items always count.
if (auto* childRenderer = child->renderer(); childRenderer && childRenderer->isListItem()) {
if (!hasVisibleMarkers && (childRenderer->style().listStyleType().type != ListStyleType::Type::None || childRenderer->style().listStyleImage() || childHasPseudoVisibleListItemMarkers(childRenderer->node())))
hasVisibleMarkers = true;
listItemCount++;
} else if (child->node() && child->node()->hasTagName(liTag)) {
// Inline elements that are in a list with an explicit role should also count.
if (m_ariaRole == AccessibilityRole::List)
listItemCount++;
if (childHasPseudoVisibleListItemMarkers(child->node())) {
hasVisibleMarkers = true;
listItemCount++;
}
}
}
}
// Non <ul> lists and ARIA lists only need to have one child.
// <ul>, <ol> lists need to have visible markers.
if (ariaRoleAttribute() != AccessibilityRole::Unknown) {
if (!listItemCount)
role = AccessibilityRole::ApplicationGroup;
} else if (!hasVisibleMarkers) {
// http://webkit.org/b/193382 lists inside of navigation hierarchies should still be considered lists.
if (Accessibility::findAncestor<AccessibilityObject>(*this, false, [] (auto& object) { return object.roleValue() == AccessibilityRole::LandmarkNavigation; }))
role = AccessibilityRole::List;
else
role = AccessibilityRole::Group;
}
return role;
}
AccessibilityRole AccessibilityList::roleValue() const
{
ASSERT(m_role != AccessibilityRole::Unknown);
return m_role;
}
} // namespace WebCore
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