public function testPrepend()
{
$array = Arr::prepend(['one', 'two', 'three', 'four'], 'zero');
$this->assertEquals(['zero', 'one', 'two', 'three', 'four'], $array);
$array = Arr::prepend(['one' => 1, 'two' => 2], 0, 'zero');
$this->assertEquals(['zero' => 0, 'one' => 1, 'two' => 2], $array);
}