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 RenderStyle& style, const RenderObject& parent)
{
if (isEditingText())
return true;
if (!length())
return false;
if (style.display() == NONE)
return false;
if (style.requiresOnlyBlockChildren())
return false;
if (!containsOnlyWhitespace())
return true;
if (!parent.canHaveWhitespaceChildren())
return false;
if (style.preserveNewline()) // pre/pre-wrap/pre-line always make renderers.
return true;
RenderObject* prev;
for (Node* sibling = this->previousSibling(); sibling; sibling = sibling->previousSibling()) {
if ((prev = sibling->renderer()))
break;
}
if (parent.isRenderInline()) {
// <span><div/> <div/></span>
if (prev && !prev->isInline())
return false;
} else {
if (parent.isRenderBlock() && !parent.isRenderParagraph() && (!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.slowFirstChild();
while (first && first->isFloatingOrOutOfFlowPositioned() && maxSiblingsToVisit--)
first = first->nextSibling();
if (!first) {
// If the block has nothing but white-space we ignore it
return false;
}
for (Node* sibling = this->nextSibling(); sibling; sibling = sibling->nextSibling()) {
if (RenderObject* nextRenderer = sibling->renderer()) {
if (nextRenderer == first) {
// Whitespace at the start of a block just goes away. Don't even
// make a render object for this text.
return false;
}
break;
}
}
}
return true;
}