function testJoin()
{
$item1 = new lmbSet(array('x' => 'C'));
$item2 = new lmbSet(array('x' => 'A'));
$item3 = new lmbSet(array('x' => 'B'));
$item4 = new lmbSet(array('x' => 'D'));
$col1 = new lmbCollection(array($item1, $item2));
$col2 = new lmbCollection(array($item3));
$col3 = array($item4);
$this->assertEqual($col1->join($col2)->join($col3), new lmbCollection(array($item1, $item2, $item3, $item4)));
}