public function testPushFrontList()
{
$l = new DoublyLinkedList();
$e1 = $l->pushFront(1);
$e2 = $l->pushBack(2);
$e3 = $l->pushBack(3);
$other = new DoublyLinkedList();
$e4 = $other->pushBack(4);
$e5 = $other->pushBack(5);
$l->pushFrontList($other);
$this->assertEquals(5, $l->len());
$this->assertEquals(4, $l->getFront()->getValue());
$this->assertEquals(5, $l->getFront()->getNext()->getValue());
$this->assertEquals($e1, $l->getFront()->getNext()->getnext());
// pushFrontList the same list will double its elements.
$other->pushFrontList($other);
$this->assertEquals(4, $other->len());
$this->assertEquals(4, $other->getFront()->getValue());
$this->assertEquals(5, $other->getFront()->getNext()->getValue());
$this->assertEquals(4, $other->getFront()->getNext()->getNext()->getValue());
// pushFrontList empty list won't alter the list.
$emptyList = new DoublyLinkedList();
$other->pushFrontList($emptyList);
$this->assertEquals(4, $other->len());
}
/**
* Inserts a copy of an other list at the front of list.
*
* Other list and current list may be the same.
*
* @param DoublyLinkedList $other Other list to insert
*
* @api
*/
public function pushFrontList(DoublyLinkedList $other)
{
for ($i = $other->len(), $el = $other->getBack(); $i > 0; $i--, $el = $el->getPrev()) {
$this->insertValue($el->getValue(), $this->root);
}
}
