/**
* 测试[Arr::unshift]的功能
*
* @dataProvider dataUnshift
* @param mixed $key
* @param mixed $val
*/
public function testUnshift($key, $val)
{
$arr = [uniqid(time()) => uniqid(), uniqid() => uniqid()];
Arr::unshift($arr, $key, $val);
$this->assertEquals(true, Arr::get($arr, $key) === $val && array_search($key, $arr) == 0);
}