public function testSortUserDefinedInArrayCollection()
{
$collection = new ArrayCollection(array(5, 5, 4, 3, 2, 1, 0));
$this->assertEquals(5, $collection->first());
$collection->sort(function ($a, $b) {
if ($a === $b) {
return 0;
}
return $a < $b ? -1 : 1;
});
$this->assertEquals(5, $collection->last());
}