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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
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "AccessibilityTableCell.h"
#include "AXObjectCache.h"
#include "AccessibilityTable.h"
#include "AccessibilityTableRow.h"
#include "ElementIterator.h"
#include "HTMLElement.h"
#include "HTMLNames.h"
#include "RenderObject.h"
#include "RenderTableCell.h"
namespace WebCore {
using namespace HTMLNames;
AccessibilityTableCell::AccessibilityTableCell(RenderObject* renderer)
: AccessibilityRenderObject(renderer)
, m_axColIndexFromRow(-1)
{
}
AccessibilityTableCell::~AccessibilityTableCell() = default;
Ref<AccessibilityTableCell> AccessibilityTableCell::create(RenderObject* renderer)
{
return adoptRef(*new AccessibilityTableCell(renderer));
}
bool AccessibilityTableCell::computeAccessibilityIsIgnored() const
{
AccessibilityObjectInclusion decision = defaultObjectInclusion();
if (decision == AccessibilityObjectInclusion::IncludeObject)
return false;
if (decision == AccessibilityObjectInclusion::IgnoreObject)
return true;
// Ignore anonymous table cells as long as they're not in a table (ie. when display:table is used).
RenderObject* renderTable = is<RenderTableCell>(renderer()) ? downcast<RenderTableCell>(*m_renderer).table() : nullptr;
bool inTable = renderTable && renderTable->node() && (renderTable->node()->hasTagName(tableTag) || nodeHasRole(renderTable->node(), "grid"_s));
if (!node() && !inTable)
return true;
if (!isTableCell())
return AccessibilityRenderObject::computeAccessibilityIsIgnored();
return false;
}
AccessibilityTable* AccessibilityTableCell::parentTable() const
{
if (!is<RenderTableCell>(renderer()))
return nullptr;
// If the document no longer exists, we might not have an axObjectCache.
if (!axObjectCache())
return nullptr;
// Do not use getOrCreate. parentTable() can be called while the render tree is being modified
// by javascript, and creating a table element may try to access the render tree while in a bad state.
// By using only get() implies that the AXTable must be created before AXTableCells. This should
// always be the case when AT clients access a table.
// https://bugs.webkit.org/show_bug.cgi?id=42652
AccessibilityObject* parentTable = axObjectCache()->get(downcast<RenderTableCell>(*m_renderer).table());
if (!is<AccessibilityTable>(parentTable))
return nullptr;
// The RenderTableCell's table() object might be anonymous sometimes. We should handle it gracefully
// by finding the right table.
if (!parentTable->node()) {
for (AccessibilityObject* parent = parentObject(); parent; parent = parent->parentObject()) {
// If this is a non-anonymous table object, but not an accessibility table, we should stop because
// we don't want to choose another ancestor table as this cell's table.
if (is<AccessibilityTable>(*parent)) {
auto& parentTable = downcast<AccessibilityTable>(*parent);
if (parentTable.isExposable())
return &parentTable;
if (parentTable.node())
break;
}
}
return nullptr;
}
return downcast<AccessibilityTable>(parentTable);
}
bool AccessibilityTableCell::isTableCell() const
{
// If the parent table is an accessibility table, then we are a table cell.
// This used to check if the unignoredParent was a row, but that exploded performance if
// this was in nested tables. This check should be just as good.
AccessibilityObject* parentTable = this->parentTable();
return is<AccessibilityTable>(parentTable) && downcast<AccessibilityTable>(*parentTable).isExposable();
}
AccessibilityRole AccessibilityTableCell::determineAccessibilityRole()
{
// AccessibilityRenderObject::determineAccessibleRole provides any ARIA-supplied
// role, falling back on the role to be used if we determine here that the element
// should not be exposed as a cell. Thus if we already know it's a cell, return that.
AccessibilityRole defaultRole = AccessibilityRenderObject::determineAccessibilityRole();
if (defaultRole == AccessibilityRole::ColumnHeader || defaultRole == AccessibilityRole::RowHeader || defaultRole == AccessibilityRole::Cell || defaultRole == AccessibilityRole::GridCell)
return defaultRole;
if (!isTableCell())
return defaultRole;
if (isColumnHeaderCell())
return AccessibilityRole::ColumnHeader;
if (isRowHeaderCell())
return AccessibilityRole::RowHeader;
return AccessibilityRole::Cell;
}
bool AccessibilityTableCell::isTableHeaderCell() const
{
return node() && node()->hasTagName(thTag);
}
bool AccessibilityTableCell::isColumnHeaderCell() const
{
const AtomString& scope = getAttribute(scopeAttr);
if (scope == "col"_s || scope == "colgroup"_s)
return true;
if (scope == "row"_s || scope == "rowgroup"_s)
return false;
if (!isTableHeaderCell())
return false;
// We are in a situation after checking the scope attribute.
// It is an attempt to resolve the type of th element without support in the specification.
// Checking tableTag and tbodyTag allows to check the case of direct row placement in the table and lets stop the loop at the table level.
for (Node* parentNode = node(); parentNode; parentNode = parentNode->parentNode()) {
if (parentNode->hasTagName(theadTag))
return true;
if (parentNode->hasTagName(tfootTag))
return false;
if (parentNode->hasTagName(tableTag) || parentNode->hasTagName(tbodyTag)) {
auto rowRange = rowIndexRange();
if (!rowRange.first)
return true;
return false;
}
}
return false;
}
bool AccessibilityTableCell::isRowHeaderCell() const
{
const AtomString& scope = getAttribute(scopeAttr);
if (scope == "row"_s || scope == "rowgroup"_s)
return true;
if (scope == "col"_s || scope == "colgroup"_s)
return false;
if (!isTableHeaderCell())
return false;
// We are in a situation after checking the scope attribute.
// It is an attempt to resolve the type of th element without support in the specification.
// Checking tableTag allows to check the case of direct row placement in the table and lets stop the loop at the table level.
for (Node* parentNode = node(); parentNode; parentNode = parentNode->parentNode()) {
if (parentNode->hasTagName(tfootTag) || parentNode->hasTagName(tbodyTag) || parentNode->hasTagName(tableTag)) {
auto colRange = columnIndexRange();
if (!colRange.first)
return true;
return false;
}
if (parentNode->hasTagName(theadTag))
return false;
}
return false;
}
bool AccessibilityTableCell::isTableCellInSameRowGroup(AXCoreObject* otherTableCell)
{
Node* parentNode = node();
for ( ; parentNode; parentNode = parentNode->parentNode()) {
if (parentNode->hasTagName(theadTag) || parentNode->hasTagName(tbodyTag) || parentNode->hasTagName(tfootTag))
break;
}
Node* otherParentNode = otherTableCell->node();
for ( ; otherParentNode; otherParentNode = otherParentNode->parentNode()) {
if (otherParentNode->hasTagName(theadTag) || otherParentNode->hasTagName(tbodyTag) || otherParentNode->hasTagName(tfootTag))
break;
}
return otherParentNode == parentNode;
}
bool AccessibilityTableCell::isTableCellInSameColGroup(AXCoreObject* tableCell)
{
auto colRange = columnIndexRange();
auto otherColRange = tableCell->columnIndexRange();
if (colRange.first <= (otherColRange.first + otherColRange.second))
return true;
return false;
}
String AccessibilityTableCell::expandedTextValue() const
{
return getAttribute(abbrAttr);
}
bool AccessibilityTableCell::supportsExpandedTextValue() const
{
return isTableHeaderCell() && hasAttribute(abbrAttr);
}
AXCoreObject::AccessibilityChildrenVector AccessibilityTableCell::columnHeaders()
{
auto* parent = parentTable();
if (!parent)
return { };
// Choose columnHeaders as the place where the "headers" attribute is reported.
auto headers = relatedObjects(AXRelationType::Headers);
// If the headers attribute returned valid values, then do not further search for column headers.
if (!headers.isEmpty())
return headers;
auto rowRange = rowIndexRange();
auto colRange = columnIndexRange();
for (unsigned row = 0; row < rowRange.first; row++) {
auto* tableCell = parent->cellForColumnAndRow(colRange.first, row);
if (!tableCell || tableCell == this || headers.contains(tableCell))
continue;
ASSERT(is<AccessibilityObject>(tableCell));
const AtomString& scope = downcast<AccessibilityObject>(tableCell)->getAttribute(scopeAttr);
if (scope == "colgroup"_s && isTableCellInSameColGroup(tableCell))
headers.append(tableCell);
else if (tableCell->isColumnHeaderCell())
headers.append(tableCell);
}
return headers;
}
AXCoreObject::AccessibilityChildrenVector AccessibilityTableCell::rowHeaders()
{
AccessibilityChildrenVector headers;
AccessibilityTable* parent = parentTable();
if (!parent)
return headers;
auto rowRange = rowIndexRange();
auto colRange = columnIndexRange();
for (unsigned column = 0; column < colRange.first; column++) {
auto* tableCell = parent->cellForColumnAndRow(column, rowRange.first);
if (!tableCell || tableCell == this || headers.contains(tableCell))
continue;
const AtomString& scope = downcast<AccessibilityObject>(tableCell)->getAttribute(scopeAttr);
if (scope == "rowgroup"_s && isTableCellInSameRowGroup(tableCell))
headers.append(tableCell);
else if (tableCell->isRowHeaderCell())
headers.append(tableCell);
}
return headers;
}
AccessibilityTableRow* AccessibilityTableCell::ariaOwnedByParent() const
{
auto owners = this->owners();
if (owners.size() == 1 && owners[0]->isTableRow())
return downcast<AccessibilityTableRow>(owners[0].get());
return nullptr;
}
AccessibilityObject* AccessibilityTableCell::parentObjectUnignored() const
{
if (auto ownerParent = ariaOwnedByParent())
return ownerParent;
return AccessibilityRenderObject::parentObjectUnignored();
}
AccessibilityTableRow* AccessibilityTableCell::parentRow() const
{
if (auto ownerParent = ariaOwnedByParent())
return ownerParent;
AXCoreObject* parent = parentObjectUnignored();
if (!is<AccessibilityTableRow>(*parent))
return nullptr;
return downcast<AccessibilityTableRow>(parent);
}
std::pair<unsigned, unsigned> AccessibilityTableCell::rowIndexRange() const
{
std::pair<unsigned, unsigned> rowRange { 0, 1 };
if (!is<RenderTableCell>(renderer()))
return rowRange;
RenderTableCell& renderCell = downcast<RenderTableCell>(*m_renderer);
// ARIA 1.1's aria-rowspan attribute is intended for cells and gridcells which are not contained
// in a native table. But if we have a valid author-provided value and do not have an explicit
// native host language value for the rowspan, expose the ARIA value.
rowRange.second = axRowSpan();
if (static_cast<int>(rowRange.second) == -1)
rowRange.second = renderCell.rowSpan();
if (AccessibilityTableRow* parentRow = this->parentRow())
rowRange.first = parentRow->rowIndex();
return rowRange;
}
std::pair<unsigned, unsigned> AccessibilityTableCell::columnIndexRange() const
{
std::pair<unsigned, unsigned> columnRange { 0, 1 };
if (!is<RenderTableCell>(renderer()))
return columnRange;
const RenderTableCell& cell = downcast<RenderTableCell>(*m_renderer);
columnRange.first = cell.table()->colToEffCol(cell.col());
// ARIA 1.1's aria-colspan attribute is intended for cells and gridcells which are not contained
// in a native table. But if we have a valid author-provided value and do not have an explicit
// native host language value for the colspan, expose the ARIA value.
columnRange.second = axColumnSpan();
if (static_cast<int>(columnRange.second) != -1)
return columnRange;
columnRange.second = cell.table()->colToEffCol(cell.col() + cell.colSpan()) - columnRange.first;
return columnRange;
}
AccessibilityObject* AccessibilityTableCell::titleUIElement() const
{
// Try to find if the first cell in this row is a <th>. If it is,
// then it can act as the title ui element. (This is only in the
// case when the table is not appearing as an AXTable.)
if (isTableCell() || !is<RenderTableCell>(renderer()))
return nullptr;
// Table cells that are th cannot have title ui elements, since by definition
// they are title ui elements
Node* node = m_renderer->node();
if (node && node->hasTagName(thTag))
return nullptr;
RenderTableCell& renderCell = downcast<RenderTableCell>(*m_renderer);
// If this cell is in the first column, there is no need to continue.
int col = renderCell.col();
if (!col)
return nullptr;
int row = renderCell.rowIndex();
RenderTableSection* section = renderCell.section();
if (!section)
return nullptr;
RenderTableCell* headerCell = section->primaryCellAt(row, 0);
if (!headerCell || headerCell == &renderCell)
return nullptr;
if (!headerCell->element() || !headerCell->element()->hasTagName(thTag))
return nullptr;
return axObjectCache()->getOrCreate(headerCell);
}
int AccessibilityTableCell::axColumnIndex() const
{
if (int value = getIntegralAttribute(aria_colindexAttr); value >= 1)
return value;
// "ARIA 1.1: If the set of columns which is present in the DOM is contiguous, and if there are no cells which span more than one row
// or column in that set, then authors may place aria-colindex on each row, setting the value to the index of the first column of the set."
// Here, we let its parent row to set its index beforehand, so we don't have to go through the siblings to calculate the index.
AccessibilityTableRow* parentRow = this->parentRow();
if (parentRow && m_axColIndexFromRow != -1)
return m_axColIndexFromRow;
return -1;
}
int AccessibilityTableCell::axRowIndex() const
{
// ARIA 1.1: Authors should place aria-rowindex on each row. Authors may also place
// aria-rowindex on all of the children or owned elements of each row.
if (int value = getIntegralAttribute(aria_rowindexAttr); value >= 1)
return value;
if (AccessibilityTableRow* parentRow = this->parentRow())
return parentRow->axRowIndex();
return -1;
}
int AccessibilityTableCell::axColumnSpan() const
{
// According to the ARIA spec, "If aria-colpan is used on an element for which the host language
// provides an equivalent attribute, user agents must ignore the value of aria-colspan."
if (hasAttribute(colspanAttr))
return -1;
// ARIA 1.1: Authors must set the value of aria-colspan to an integer greater than or equal to 1.
if (int value = getIntegralAttribute(aria_colspanAttr); value >= 1)
return value;
return -1;
}
int AccessibilityTableCell::axRowSpan() const
{
// According to the ARIA spec, "If aria-rowspan is used on an element for which the host language
// provides an equivalent attribute, user agents must ignore the value of aria-rowspan."
if (hasAttribute(rowspanAttr))
return -1;
// ARIA 1.1: Authors must set the value of aria-rowspan to an integer greater than or equal to 0.
// Setting the value to 0 indicates that the cell or gridcell is to span all the remaining rows in the row group.
if (getAttribute(aria_rowspanAttr) == "0"_s)
return 0;
if (int value = getIntegralAttribute(aria_rowspanAttr); value >= 1)
return value;
return -1;
}
} // namespace WebCore