public function testDifference()
{
// from js
$result = __u::difference(array(1, 2, 3), array(2, 30, 40));
$this->assertEquals(array(1, 3), $result, 'takes the difference of two arrays');
$result = __u::difference(array(1, 2, 3, 4), array(2, 30, 40), array(1, 11, 111));
$this->assertEquals('3 4', join(' ', $result), 'takes the difference of three arrays');
// extra
$result = __u(array(1, 2, 3))->difference(array(2, 30, 40));
$this->assertEquals(array(1, 3), $result, 'works with OO-style call');
// docs
$this->assertEquals(array(1, 3, 4), __u::difference(array(1, 2, 3, 4, 5), array(5, 2, 10)));
}
