bool HTMLFormElement::rendererIsNeeded(const NodeRenderingContext& context)
{
if (!m_wasDemoted)
return HTMLElement::rendererIsNeeded(context);
ContainerNode* node = parentNode();
RenderObject* parentRenderer = node->renderer();
// FIXME: Shouldn't we also check for table caption (see |formIsTablePart| below).
bool parentIsTableElementPart = (parentRenderer->isTable() && node->hasTagName(tableTag))
|| (parentRenderer->isTableRow() && node->hasTagName(trTag))
|| (parentRenderer->isTableSection() && node->hasTagName(tbodyTag))
|| (parentRenderer->isRenderTableCol() && node->hasTagName(colTag))
|| (parentRenderer->isTableCell() && node->hasTagName(trTag));
if (!parentIsTableElementPart)
return true;
EDisplay display = context.style()->display();
bool formIsTablePart = display == TABLE || display == INLINE_TABLE || display == TABLE_ROW_GROUP
|| display == TABLE_HEADER_GROUP || display == TABLE_FOOTER_GROUP || display == TABLE_ROW
|| display == TABLE_COLUMN_GROUP || display == TABLE_COLUMN || display == TABLE_CELL
|| display == TABLE_CAPTION;
return formIsTablePart;
}
bool Text::textRendererIsNeeded(const NodeRenderingContext& context)
{
if (isEditingText())
return true;
if (!length())
return false;
if (context.style()->display() == NONE)
return false;
if (!containsOnlyWhitespace())
return true;
RenderObject* parent = context.parentRenderer();
if (!parent->canHaveWhitespaceChildren())
return false;
if (context.style()->preserveNewline()) // pre/pre-wrap/pre-line always make renderers.
return true;
RenderObject* prev = context.previousRenderer();
if (prev && prev->isBR()) // <span><br/> <br/></span>
return false;
if (parent->isRenderInline()) {
// <span><div/> <div/></span>
if (prev && !prev->isInline())
return false;
} else {
if (parent->isRenderBlock() && !parent->childrenInline() && (!prev || !prev->isInline()))
return false;
// Avoiding creation of a Renderer for the text node is a non-essential memory optimization.
// So to avoid blowing up on very wide DOMs, we limit the number of siblings to visit.
unsigned maxSiblingsToVisit = 50;
RenderObject* first = parent->firstChild();
while (first && first->isFloatingOrOutOfFlowPositioned() && maxSiblingsToVisit--)
first = first->nextSibling();
if (!first || context.nextRenderer() == first)
// Whitespace at the start of a block just goes away. Don't even
// make a render object for this text.
return false;
}
return true;
}
bool Text::textRendererIsNeeded(const NodeRenderingContext& context)
{
if (isEditingText())
return true;
if (!length())
return false;
if (context.style()->display() == NONE)
return false;
bool onlyWS = containsOnlyWhitespace();
if (!onlyWS)
return true;
RenderObject* parent = context.parentRenderer();
if (parent->isTable() || parent->isTableRow() || parent->isTableSection() || parent->isRenderTableCol() || parent->isFrameSet())
return false;
if (context.style()->preserveNewline()) // pre/pre-wrap/pre-line always make renderers.
return true;
RenderObject* prev = context.previousRenderer();
if (prev && prev->isBR()) // <span><br/> <br/></span>
return false;
if (parent->isRenderInline()) {
// <span><div/> <div/></span>
if (prev && !prev->isInline())
return false;
} else {
if (parent->isRenderBlock() && !parent->childrenInline() && (!prev || !prev->isInline()))
return false;
RenderObject* first = parent->firstChild();
while (first && first->isFloatingOrOutOfFlowPositioned())
first = first->nextSibling();
if (!first || context.nextRenderer() == first) {
// Whitespace at the start of a block just goes away. Don't even
// make a render object for this text.
return false;
}
}
return true;
}
bool HTMLIFrameElement::rendererIsNeeded(const NodeRenderingContext& context)
{
return isURLAllowed() && context.style()->display() != NONE;
}
bool HTMLFrameSetElement::rendererIsNeeded(const NodeRenderingContext& context)
{
// For compatibility, frames render even when display: none is set.
// However, we delay creating a renderer until stylesheets have loaded.
return context.style()->isStyleAvailable();
}
bool PseudoElement::rendererIsNeeded(const NodeRenderingContext& context)
{
return pseudoElementRendererIsNeeded(context.style());
}
