bool AccessibilityTable::isDataTable() const
{
if (!m_renderer)
return false;
// Do not consider it a data table is it has an ARIA role.
if (hasARIARole())
return false;
// When a section of the document is contentEditable, all tables should be
// treated as data tables, otherwise users may not be able to work with rich
// text editors that allow creating and editing tables.
if (node() && node()->hasEditableStyle())
return true;
// This employs a heuristic to determine if this table should appear.
// Only "data" tables should be exposed as tables.
// Unfortunately, there is no good way to determine the difference
// between a "layout" table and a "data" table.
RenderTable* table = toRenderTable(m_renderer);
if (!table->element() || !isHTMLTableElement(table->element()))
return false;
// if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
HTMLTableElement* tableElement = toHTMLTableElement(table->element());
if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
return true;
// if someone used "rules" attribute than the table should appear
if (!tableElement->rules().isEmpty())
return true;
// if there's a colgroup or col element, it's probably a data table.
for (const auto& child : childrenOfType<Element>(*tableElement)) {
if (child.hasTagName(colTag) || child.hasTagName(colgroupTag))
return true;
}
// go through the cell's and check for tell-tale signs of "data" table status
// cells have borders, or use attributes like headers, abbr, scope or axis
table->recalcSectionsIfNeeded();
RenderTableSection* firstBody = table->firstBody();
if (!firstBody)
return false;
int numCols = firstBody->numColumns();
int numRows = firstBody->numRows();
// If there's only one cell, it's not a good AXTable candidate.
if (numRows == 1 && numCols == 1)
return false;
// If there are at least 20 rows, we'll call it a data table.
if (numRows >= 20)
return true;
// Store the background color of the table to check against cell's background colors.
const RenderStyle& tableStyle = table->style();
Color tableBGColor = tableStyle.visitedDependentColor(CSSPropertyBackgroundColor);
// check enough of the cells to find if the table matches our criteria
// Criteria:
// 1) must have at least one valid cell (and)
// 2) at least half of cells have borders (or)
// 3) at least half of cells have different bg colors than the table, and there is cell spacing
unsigned validCellCount = 0;
unsigned borderedCellCount = 0;
unsigned backgroundDifferenceCellCount = 0;
unsigned cellsWithTopBorder = 0;
unsigned cellsWithBottomBorder = 0;
unsigned cellsWithLeftBorder = 0;
unsigned cellsWithRightBorder = 0;
Color alternatingRowColors[5];
int alternatingRowColorCount = 0;
int headersInFirstColumnCount = 0;
for (int row = 0; row < numRows; ++row) {
int headersInFirstRowCount = 0;
for (int col = 0; col < numCols; ++col) {
RenderTableCell* cell = firstBody->primaryCellAt(row, col);
if (!cell)
continue;
Element* cellElement = cell->element();
if (!cellElement)
continue;
if (cell->width() < 1 || cell->height() < 1)
continue;
validCellCount++;
bool isTHCell = cellElement->hasTagName(thTag);
// If the first row is comprised of all <th> tags, assume it is a data table.
if (!row && isTHCell)
headersInFirstRowCount++;
// If the first column is comprised of all <th> tags, assume it is a data table.
if (!col && isTHCell)
headersInFirstColumnCount++;
// In this case, the developer explicitly assigned a "data" table attribute.
if (cellElement->hasTagName(tdTag) || cellElement->hasTagName(thTag)) {
HTMLTableCellElement* tableCellElement = toHTMLTableCellElement(cellElement);
if (!tableCellElement->headers().isEmpty() || !tableCellElement->abbr().isEmpty()
|| !tableCellElement->axis().isEmpty() || !tableCellElement->scope().isEmpty())
return true;
}
const RenderStyle& renderStyle = cell->style();
// If the empty-cells style is set, we'll call it a data table.
if (renderStyle.emptyCells() == HIDE)
return true;
// If a cell has matching bordered sides, call it a (fully) bordered cell.
if ((cell->borderTop() > 0 && cell->borderBottom() > 0)
|| (cell->borderLeft() > 0 && cell->borderRight() > 0))
borderedCellCount++;
// Also keep track of each individual border, so we can catch tables where most
// cells have a bottom border, for example.
if (cell->borderTop() > 0)
cellsWithTopBorder++;
if (cell->borderBottom() > 0)
cellsWithBottomBorder++;
if (cell->borderLeft() > 0)
cellsWithLeftBorder++;
if (cell->borderRight() > 0)
cellsWithRightBorder++;
// If the cell has a different color from the table and there is cell spacing,
// then it is probably a data table cell (spacing and colors take the place of borders).
Color cellColor = renderStyle.visitedDependentColor(CSSPropertyBackgroundColor);
if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0
&& tableBGColor != cellColor && cellColor.alpha() != 1)
backgroundDifferenceCellCount++;
// If we've found 10 "good" cells, we don't need to keep searching.
if (borderedCellCount >= 10 || backgroundDifferenceCellCount >= 10)
return true;
// For the first 5 rows, cache the background color so we can check if this table has zebra-striped rows.
if (row < 5 && row == alternatingRowColorCount) {
RenderObject* renderRow = cell->parent();
if (!renderRow || !renderRow->isBoxModelObject() || !toRenderBoxModelObject(renderRow)->isTableRow())
continue;
const RenderStyle& rowRenderStyle = renderRow->style();
Color rowColor = rowRenderStyle.visitedDependentColor(CSSPropertyBackgroundColor);
alternatingRowColors[alternatingRowColorCount] = rowColor;
alternatingRowColorCount++;
}
}
if (!row && headersInFirstRowCount == numCols && numCols > 1)
return true;
}
if (headersInFirstColumnCount == numRows && numRows > 1)
return true;
// if there is less than two valid cells, it's not a data table
if (validCellCount <= 1)
return false;
// half of the cells had borders, it's a data table
unsigned neededCellCount = validCellCount / 2;
if (borderedCellCount >= neededCellCount
|| cellsWithTopBorder >= neededCellCount
|| cellsWithBottomBorder >= neededCellCount
|| cellsWithLeftBorder >= neededCellCount
|| cellsWithRightBorder >= neededCellCount)
return true;
// half had different background colors, it's a data table
if (backgroundDifferenceCellCount >= neededCellCount)
return true;
// Check if there is an alternating row background color indicating a zebra striped style pattern.
if (alternatingRowColorCount > 2) {
Color firstColor = alternatingRowColors[0];
for (int k = 1; k < alternatingRowColorCount; k++) {
// If an odd row was the same color as the first row, its not alternating.
if (k % 2 == 1 && alternatingRowColors[k] == firstColor)
return false;
// If an even row is not the same as the first row, its not alternating.
if (!(k % 2) && alternatingRowColors[k] != firstColor)
return false;
}
return true;
}
return false;
}
CollapsedBorderValue RenderTableCell::collapsedBeforeBorder() const
{
RenderTable* table = this->table();
// For before border, we need to check, in order of precedence:
// (1) Our before border.
int before = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderBeforeColor, table->style()->direction(), table->style()->writingMode());
int after = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderAfterColor, table->style()->direction(), table->style()->writingMode());
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderBefore(), style()->visitedDependentColor(before), BCELL);
RenderTableCell* prevCell = table->cellAbove(this);
if (prevCell) {
// (2) A before cell's after border.
result = chooseBorder(CollapsedBorderValue(&prevCell->style()->borderAfter(), prevCell->style()->visitedDependentColor(after), BCELL), result);
if (!result.exists())
return result;
}
// (3) Our row's before border.
result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderBefore(), parent()->style()->visitedDependentColor(before), BROW));
if (!result.exists())
return result;
// (4) The previous row's after border.
if (prevCell) {
RenderObject* prevRow = 0;
if (prevCell->section() == section())
prevRow = parent()->previousSibling();
else
prevRow = prevCell->section()->lastChild();
if (prevRow) {
result = chooseBorder(CollapsedBorderValue(&prevRow->style()->borderAfter(), prevRow->style()->visitedDependentColor(after), BROW), result);
if (!result.exists())
return result;
}
}
// Now check row groups.
RenderTableSection* currSection = section();
if (!row()) {
// (5) Our row group's before border.
result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderBefore(), currSection->style()->visitedDependentColor(before), BROWGROUP));
if (!result.exists())
return result;
// (6) Previous row group's after border.
currSection = table->sectionAbove(currSection);
if (currSection) {
result = chooseBorder(CollapsedBorderValue(&currSection->style()->borderAfter(), currSection->style()->visitedDependentColor(after), BROWGROUP), result);
if (!result.exists())
return result;
}
}
if (!currSection) {
// (8) Our column and column group's before borders.
RenderTableCol* colElt = table->colElement(col());
if (colElt) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderBefore(), colElt->style()->visitedDependentColor(before), BCOL));
if (!result.exists())
return result;
if (colElt->parent()->isTableCol()) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderBefore(), colElt->parent()->style()->visitedDependentColor(before), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (9) The table's before border.
result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderBefore(), table->style()->visitedDependentColor(before), BTABLE));
if (!result.exists())
return result;
}
return result;
}
CollapsedBorderValue RenderTableCell::collapsedAfterBorder() const
{
RenderTable* table = this->table();
// For after border, we need to check, in order of precedence:
// (1) Our after border.
int before = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderBeforeColor, table->style()->direction(), table->style()->writingMode());
int after = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderAfterColor, table->style()->direction(), table->style()->writingMode());
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderAfter(), style()->visitedDependentColor(after), BCELL);
RenderTableCell* nextCell = table->cellBelow(this);
if (nextCell) {
// (2) An after cell's before border.
result = chooseBorder(result, CollapsedBorderValue(&nextCell->style()->borderBefore(), nextCell->style()->visitedDependentColor(before), BCELL));
if (!result.exists())
return result;
}
// (3) Our row's after border. (FIXME: Deal with rowspan!)
result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderAfter(), parent()->style()->visitedDependentColor(after), BROW));
if (!result.exists())
return result;
// (4) The next row's before border.
if (nextCell) {
result = chooseBorder(result, CollapsedBorderValue(&nextCell->parent()->style()->borderBefore(), nextCell->parent()->style()->visitedDependentColor(before), BROW));
if (!result.exists())
return result;
}
// Now check row groups.
RenderTableSection* currSection = section();
if (row() + rowSpan() >= currSection->numRows()) {
// (5) Our row group's after border.
result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderAfter(), currSection->style()->visitedDependentColor(after), BROWGROUP));
if (!result.exists())
return result;
// (6) Following row group's before border.
currSection = table->sectionBelow(currSection);
if (currSection) {
result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderBefore(), currSection->style()->visitedDependentColor(before), BROWGROUP));
if (!result.exists())
return result;
}
}
if (!currSection) {
// (8) Our column and column group's after borders.
RenderTableCol* colElt = table->colElement(col());
if (colElt) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderAfter(), colElt->style()->visitedDependentColor(after), BCOL));
if (!result.exists()) return result;
if (colElt->parent()->isTableCol()) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderAfter(), colElt->parent()->style()->visitedDependentColor(after), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (9) The table's after border.
result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderAfter(), table->style()->visitedDependentColor(after), BTABLE));
if (!result.exists())
return result;
}
return result;
}
CollapsedBorderValue RenderTableCell::collapsedEndBorder() const
{
RenderTable* table = this->table();
bool isEndColumn = table->colToEffCol(col() + colSpan() - 1) == table->numEffCols() - 1;
// For end border, we need to check, in order of precedence:
// (1) Our end border.
int start = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderStartColor, table->style()->direction(), table->style()->writingMode());
int end = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderEndColor, table->style()->direction(), table->style()->writingMode());
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderEnd(), style()->visitedDependentColor(end), BCELL);
// (2) The start border of the following cell.
if (!isEndColumn) {
RenderTableCell* nextCell = table->cellAfter(this);
if (nextCell && nextCell->style()) {
CollapsedBorderValue startBorder = CollapsedBorderValue(&nextCell->style()->borderStart(), nextCell->style()->visitedDependentColor(start), BCELL);
result = chooseBorder(result, startBorder);
if (!result.exists())
return result;
}
} else {
// (3) Our row's end border.
result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderEnd(), parent()->style()->visitedDependentColor(end), BROW));
if (!result.exists())
return result;
// (4) Our row group's end border.
result = chooseBorder(result, CollapsedBorderValue(§ion()->style()->borderEnd(), section()->style()->visitedDependentColor(end), BROWGROUP));
if (!result.exists())
return result;
}
// (5) Our column and column group's end borders.
bool startColEdge;
bool endColEdge;
RenderTableCol* colElt = table->colElement(col() + colSpan() - 1, &startColEdge, &endColEdge);
if (colElt && endColEdge) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderEnd(), colElt->style()->visitedDependentColor(end), BCOL));
if (!result.exists())
return result;
if (colElt->parent()->isTableCol() && !colElt->nextSibling()) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderEnd(), colElt->parent()->style()->visitedDependentColor(end), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (6) The start border of the next column.
if (!isEndColumn) {
colElt = table->colElement(col() + colSpan(), &startColEdge, &endColEdge);
if (colElt && startColEdge) {
CollapsedBorderValue startBorder = CollapsedBorderValue(&colElt->style()->borderStart(), colElt->style()->visitedDependentColor(start), BCOL);
result = chooseBorder(result, startBorder);
if (!result.exists())
return result;
}
} else {
// (7) The table's end border.
result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderEnd(), table->style()->visitedDependentColor(end), BTABLE));
if (!result.exists())
return result;
}
return result;
}
CollapsedBorderValue RenderTableCell::collapsedStartBorder() const
{
RenderTable* table = this->table();
bool isStartColumn = col() == 0;
// For the start border, we need to check, in order of precedence:
// (1) Our start border.
int start = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderStartColor, table->style()->direction(), table->style()->writingMode());
int end = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderEndColor, table->style()->direction(), table->style()->writingMode());
CollapsedBorderValue result(&style()->borderStart(), style()->visitedDependentColor(start), BCELL);
// (2) The end border of the preceding cell.
if (RenderTableCell* prevCell = table->cellBefore(this)) {
CollapsedBorderValue prevCellBorder = CollapsedBorderValue(&prevCell->style()->borderEnd(), prevCell->style()->visitedDependentColor(end), BCELL);
result = chooseBorder(prevCellBorder, result);
if (!result.exists())
return result;
} else if (isStartColumn) {
// (3) Our row's start border.
result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderStart(), parent()->style()->visitedDependentColor(start), BROW));
if (!result.exists())
return result;
// (4) Our row group's start border.
result = chooseBorder(result, CollapsedBorderValue(§ion()->style()->borderStart(), section()->style()->visitedDependentColor(start), BROWGROUP));
if (!result.exists())
return result;
}
// (5) Our column and column group's start borders.
bool startColEdge;
bool endColEdge;
RenderTableCol* colElt = table->colElement(col(), &startColEdge, &endColEdge);
if (colElt && startColEdge) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderStart(), colElt->style()->visitedDependentColor(start), BCOL));
if (!result.exists())
return result;
if (colElt->parent()->isTableCol() && !colElt->previousSibling()) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderStart(), colElt->parent()->style()->visitedDependentColor(start), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (6) The end border of the preceding column.
if (!isStartColumn) {
colElt = table->colElement(col() -1, &startColEdge, &endColEdge);
if (colElt && endColEdge) {
CollapsedBorderValue endBorder = CollapsedBorderValue(&colElt->style()->borderEnd(), colElt->style()->visitedDependentColor(end), BCOL);
result = chooseBorder(endBorder, result);
if (!result.exists())
return result;
}
} else {
// (7) The table's start border.
result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderStart(), table->style()->visitedDependentColor(start), BTABLE));
if (!result.exists())
return result;
}
return result;
}
bool AccessibilityTable::isTableExposableThroughAccessibility()
{
// the following is a heuristic used to determine if a
// <table> should be exposed as an AXTable. The goal
// is to only show "data" tables
if (!m_renderer || !m_renderer->isTable())
return false;
// if the developer assigned an aria role to this, then we shouldn't
// expose it as a table, unless, of course, the aria role is a table
AccessibilityRole ariaRole = ariaRoleAttribute();
if (ariaRole == TableRole)
return true;
if (ariaRole != UnknownRole)
return false;
RenderTable* table = static_cast<RenderTable*>(m_renderer);
// this employs a heuristic to determine if this table should appear.
// Only "data" tables should be exposed as tables.
// Unfortunately, there is no good way to determine the difference
// between a "layout" table and a "data" table
Node* tableNode = table->element();
if (!tableNode || !tableNode->hasTagName(tableTag))
return false;
// if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
HTMLTableElement* tableElement = static_cast<HTMLTableElement*>(tableNode);
if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
return true;
// if someone used "rules" attribute than the table should appear
if (!tableElement->rules().isEmpty())
return true;
// go through the cell's and check for tell-tale signs of "data" table status
// cells have borders, or use attributes like headers, abbr, scope or axis
RenderTableSection* firstBody = table->firstBody();
if (!firstBody)
return false;
int numCols = firstBody->numColumns();
int numRows = firstBody->numRows();
// if there's only one cell, it's not a good AXTable candidate
if (numRows == 1 && numCols == 1)
return false;
// store the background color of the table to check against cell's background colors
RenderStyle* tableStyle = table->style();
if (!tableStyle)
return false;
Color tableBGColor = tableStyle->backgroundColor();
// check enough of the cells to find if the table matches our criteria
// Criteria:
// 1) must have at least one valid cell (and)
// 2) at least half of cells have borders (or)
// 3) at least half of cells have different bg colors than the table, and there is cell spacing
unsigned validCellCount = 0;
unsigned borderedCellCount = 0;
unsigned backgroundDifferenceCellCount = 0;
for (int row = 0; row < numRows; ++row) {
for (int col = 0; col < numCols; ++col) {
RenderTableCell* cell = firstBody->cellAt(row, col).cell;
if (!cell)
continue;
Node* cellNode = cell->element();
if (!cellNode)
continue;
if (cell->width() < 1 || cell->height() < 1)
continue;
validCellCount++;
HTMLTableCellElement* cellElement = static_cast<HTMLTableCellElement*>(cellNode);
// in this case, the developer explicitly assigned a "data" table attribute
if (!cellElement->headers().isEmpty() || !cellElement->abbr().isEmpty() ||
!cellElement->axis().isEmpty() || !cellElement->scope().isEmpty())
return true;
RenderStyle* renderStyle = cell->style();
if (!renderStyle)
continue;
// a cell needs to have matching bordered sides, before it can be considered a bordered cell.
if ((cell->borderTop() > 0 && cell->borderBottom() > 0) ||
(cell->borderLeft() > 0 && cell->borderRight() > 0))
borderedCellCount++;
// if the cell has a different color from the table and there is cell spacing,
// then it is probably a data table cell (spacing and colors take the place of borders)
Color cellColor = renderStyle->backgroundColor();
if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0 &&
tableBGColor != cellColor && cellColor.alpha() != 1)
backgroundDifferenceCellCount++;
// if we've found 10 "good" cells, we don't need to keep searching
if (borderedCellCount >= 10 || backgroundDifferenceCellCount >= 10)
return true;
}
}
// if there is less than two valid cells, it's not a data table
if (validCellCount <= 1)
return false;
// half of the cells had borders, it's a data table
unsigned neededCellCount = validCellCount / 2;
if (borderedCellCount >= neededCellCount)
return true;
// half had different background colors, it's a data table
if (backgroundDifferenceCellCount >= neededCellCount)
return true;
return false;
}
bool AccessibilityTable::isDataTable() const
{
if (!m_renderer)
return false;
// Do not consider it a data table is it has an ARIA role.
if (hasARIARole())
return false;
// This employs a heuristic to determine if this table should appear.
// Only "data" tables should be exposed as tables.
// Unfortunately, there is no good way to determine the difference
// between a "layout" table and a "data" table.
RenderTable* table = toRenderTable(m_renderer);
Node* tableNode = table->node();
if (!tableNode || !tableNode->hasTagName(tableTag))
return false;
// if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
HTMLTableElement* tableElement = static_cast<HTMLTableElement*>(tableNode);
if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
return true;
// if someone used "rules" attribute than the table should appear
if (!tableElement->rules().isEmpty())
return true;
// go through the cell's and check for tell-tale signs of "data" table status
// cells have borders, or use attributes like headers, abbr, scope or axis
RenderTableSection* firstBody = table->firstBody();
if (!firstBody)
return false;
int numCols = firstBody->numColumns();
int numRows = firstBody->numRows();
// if there's only one cell, it's not a good AXTable candidate
if (numRows == 1 && numCols == 1)
return false;
// store the background color of the table to check against cell's background colors
RenderStyle* tableStyle = table->style();
if (!tableStyle)
return false;
Color tableBGColor = tableStyle->visitedDependentColor(CSSPropertyBackgroundColor);
// check enough of the cells to find if the table matches our criteria
// Criteria:
// 1) must have at least one valid cell (and)
// 2) at least half of cells have borders (or)
// 3) at least half of cells have different bg colors than the table, and there is cell spacing
unsigned validCellCount = 0;
unsigned borderedCellCount = 0;
unsigned backgroundDifferenceCellCount = 0;
Color alternatingRowColors[5];
int alternatingRowColorCount = 0;
int headersInFirstColumnCount = 0;
for (int row = 0; row < numRows; ++row) {
int headersInFirstRowCount = 0;
for (int col = 0; col < numCols; ++col) {
RenderTableCell* cell = firstBody->primaryCellAt(row, col);
if (!cell)
continue;
Node* cellNode = cell->node();
if (!cellNode)
continue;
if (cell->width() < 1 || cell->height() < 1)
continue;
validCellCount++;
HTMLTableCellElement* cellElement = static_cast<HTMLTableCellElement*>(cellNode);
bool isTHCell = cellElement->hasTagName(thTag);
// If the first row is comprised of all <th> tags, assume it is a data table.
if (!row && isTHCell)
headersInFirstRowCount++;
// If the first column is comprised of all <th> tags, assume it is a data table.
if (!col && isTHCell)
headersInFirstColumnCount++;
// in this case, the developer explicitly assigned a "data" table attribute
if (!cellElement->headers().isEmpty() || !cellElement->abbr().isEmpty()
|| !cellElement->axis().isEmpty() || !cellElement->scope().isEmpty())
return true;
RenderStyle* renderStyle = cell->style();
if (!renderStyle)
continue;
// a cell needs to have matching bordered sides, before it can be considered a bordered cell.
if ((cell->borderTop() > 0 && cell->borderBottom() > 0)
|| (cell->borderLeft() > 0 && cell->borderRight() > 0))
borderedCellCount++;
// if the cell has a different color from the table and there is cell spacing,
// then it is probably a data table cell (spacing and colors take the place of borders)
Color cellColor = renderStyle->visitedDependentColor(CSSPropertyBackgroundColor);
if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0
&& tableBGColor != cellColor && cellColor.alpha() != 1)
backgroundDifferenceCellCount++;
// if we've found 10 "good" cells, we don't need to keep searching
if (borderedCellCount >= 10 || backgroundDifferenceCellCount >= 10)
return true;
// For the first 5 rows, cache the background color so we can check if this table has zebra-striped rows.
if (row < 5 && row == alternatingRowColorCount) {
RenderObject* renderRow = cell->parent();
if (!renderRow || !renderRow->isBoxModelObject() || !toRenderBoxModelObject(renderRow)->isTableRow())
continue;
RenderStyle* rowRenderStyle = renderRow->style();
if (!rowRenderStyle)
continue;
Color rowColor = rowRenderStyle->visitedDependentColor(CSSPropertyBackgroundColor);
alternatingRowColors[alternatingRowColorCount] = rowColor;
alternatingRowColorCount++;
}
}
if (!row && headersInFirstRowCount == numCols && numCols > 1)
return true;
}
if (headersInFirstColumnCount == numRows && numRows > 1)
return true;
// if there is less than two valid cells, it's not a data table
if (validCellCount <= 1)
return false;
// half of the cells had borders, it's a data table
unsigned neededCellCount = validCellCount / 2;
if (borderedCellCount >= neededCellCount)
return true;
// half had different background colors, it's a data table
if (backgroundDifferenceCellCount >= neededCellCount)
return true;
// Check if there is an alternating row background color indicating a zebra striped style pattern.
if (alternatingRowColorCount > 2) {
Color firstColor = alternatingRowColors[0];
for (int k = 1; k < alternatingRowColorCount; k++) {
// If an odd row was the same color as the first row, its not alternating.
if (k % 2 == 1 && alternatingRowColors[k] == firstColor)
return false;
// If an even row is not the same as the first row, its not alternating.
if (!(k % 2) && alternatingRowColors[k] != firstColor)
return false;
}
return true;
}
return false;
}
CollapsedBorderValue RenderTableCell::collapsedRightBorder(bool rtl) const
{
RenderTable* tableElt = table();
bool rightmostColumn;
if (rtl)
rightmostColumn = col() == 0;
else {
int effCol = tableElt->colToEffCol(col() + colSpan() - 1);
rightmostColumn = effCol == tableElt->numEffCols() - 1;
}
// For border right, we need to check, in order of precedence:
// (1) Our right border.
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderRight(), BCELL);
// (2) The left border of the cell to the right.
if (!rightmostColumn) {
RenderTableCell* nextCell = rtl ? tableElt->cellBefore(this) : tableElt->cellAfter(this);
if (nextCell && nextCell->style()) {
result = rtl ? compareBorders(CollapsedBorderValue(&nextCell->style()->borderLeft(), BCELL), result) : compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderLeft(), BCELL));
if (!result.exists())
return result;
}
} else {
// (3) Our row's right border.
result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderRight(), BROW));
if (!result.exists())
return result;
// (4) Our row group's right border.
result = compareBorders(result, CollapsedBorderValue(§ion()->style()->borderRight(), BROWGROUP));
if (!result.exists())
return result;
}
// (5) Our column and column group's right borders.
bool startColEdge;
bool endColEdge;
RenderTableCol* colElt = tableElt->colElement(col() + (rtl ? 0 : colSpan() - 1), &startColEdge, &endColEdge);
if (colElt && (!rtl ? endColEdge : startColEdge)) {
result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderRight(), BCOL));
if (!result.exists())
return result;
if (colElt->parent()->isTableCol() && (!rtl ? !colElt->nextSibling() : !colElt->previousSibling())) {
result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderRight(), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (6) The left border of the column to the right.
if (!rightmostColumn) {
colElt = tableElt->colElement(col() + (rtl ? -1 : colSpan()), &startColEdge, &endColEdge);
if (colElt && (!rtl ? startColEdge : endColEdge)) {
result = rtl ? compareBorders(CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL), result) : compareBorders(result, CollapsedBorderValue(&colElt->style()->borderLeft(), BCOL));
if (!result.exists())
return result;
}
} else {
// (7) The table's right border.
result = compareBorders(result, CollapsedBorderValue(&tableElt->style()->borderRight(), BTABLE));
if (!result.exists())
return result;
}
return result;
}
