static bool isValidColumnSpanner(RenderMultiColumnFlowThread* flowThread, RenderObject* descendant)
{
// We assume that we're inside the flow thread. This function is not to be called otherwise.
ASSERT(descendant->isDescendantOf(flowThread));
// First make sure that the renderer itself has the right properties for becoming a spanner.
RenderStyle& style = descendant->style();
if (style.columnSpan() != ColumnSpanAll || !descendant->isBox() || descendant->isFloatingOrOutOfFlowPositioned())
return false;
RenderBlock* container = descendant->containingBlock();
if (!container->isRenderBlockFlow() || container->childrenInline()) {
// Needs to be block-level.
return false;
}
// This looks like a spanner, but if we're inside something unbreakable, it's not to be treated as one.
for (RenderBox* ancestor = toRenderBox(descendant)->parentBox(); ancestor; ancestor = ancestor->parentBox()) {
if (ancestor->isRenderFlowThread()) {
// Don't allow any intervening non-multicol fragmentation contexts. The spec doesn't say
// anything about disallowing this, but it's just going to be too complicated to
// implement (not to mention specify behavior).
return ancestor == flowThread;
}
ASSERT(ancestor->style().columnSpan() != ColumnSpanAll || !isValidColumnSpanner(flowThread, ancestor));
if (ancestor->isUnsplittableForPagination())
return false;
}
ASSERT_NOT_REACHED();
return false;
}
void RenderBoxModelObject::moveChildrenTo(RenderBoxModelObject* toBoxModelObject, RenderObject* startChild, RenderObject* endChild, RenderObject* beforeChild, bool fullRemoveInsert)
{
// This condition is rarely hit since this function is usually called on
// anonymous blocks which can no longer carry positioned objects (see r120761)
// or when fullRemoveInsert is false.
if (fullRemoveInsert && isRenderBlock()) {
RenderBlock* block = toRenderBlock(this);
block->removePositionedObjects(0);
if (block->isRenderBlockFlow())
toRenderBlockFlow(block)->removeFloatingObjects();
}
ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
for (RenderObject* child = startChild; child && child != endChild; ) {
// Save our next sibling as moveChildTo will clear it.
RenderObject* nextSibling = child->nextSibling();
moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
child = nextSibling;
}
}