LayoutMultiColumnSet* LayoutMultiColumnSet::nextSiblingMultiColumnSet() const
{
for (LayoutObject* sibling = nextSibling(); sibling; sibling = sibling->nextSibling()) {
if (sibling->isLayoutMultiColumnSet())
return toLayoutMultiColumnSet(sibling);
}
return nullptr;
}
LayoutMultiColumnSet* LayoutMultiColumnFlowThread::lastMultiColumnSet() const
{
for (LayoutObject* sibling = multiColumnBlockFlow()->lastChild(); sibling; sibling = sibling->previousSibling()) {
if (sibling->isLayoutMultiColumnSet())
return toLayoutMultiColumnSet(sibling);
}
return nullptr;
}
// When processing layout objects to remove or when processing layout objects that have just been
// inserted, certain types of objects should be skipped.
static bool shouldSkipInsertedOrRemovedChild(LayoutMultiColumnFlowThread* flowThread, const LayoutObject& child)
{
if (child.isSVG() && !child.isSVGRoot()) {
// Don't descend into SVG objects. What's in there is of no interest, and there might even
// be a foreignObject there with column-span:all, which doesn't apply to us.
return true;
}
if (child.isLayoutFlowThread()) {
// Found an inner flow thread. We need to skip it and its descendants.
return true;
}
if (child.isLayoutMultiColumnSet() || child.isLayoutMultiColumnSpannerPlaceholder()) {
// Column sets and spanner placeholders in a child multicol context don't affect the parent
// flow thread.
return true;
}
if (child.isOutOfFlowPositioned() && child.containingBlock()->flowThreadContainingBlock() != flowThread) {
// Out-of-flow with its containing block on the outside of the multicol container.
return true;
}
return false;
}
