/**
* @param Node $node
*/
protected function setParent(Node $node)
{
if ($node && !$node instanceof self) {
throw new \InvalidArgumentException('Parent of block must also be block (can not be inline)');
}
parent::setParent($node);
}
/**
* @param Node $sibling
*/
public function insertBefore(Node $sibling)
{
$sibling->detach();
$sibling->previous = $this->previous;
if ($sibling->previous) {
$sibling->previous->next = $sibling;
}
$sibling->next = $this;
$this->previous = $sibling;
$sibling->setParent($this->parent);
if (!$sibling->previous) {
$sibling->parent->firstChild = $sibling;
}
}
