public function test_values_at_extra_key()
{
$name = array('name' => 'John Doe', 'first' => 'John', 'middle' => 'M', 'last' => 'Doe', 'title' => 'Dr.');
$result = Enumerator::values_at($name, 'title', 'suffix');
$expected = array('title' => 'Dr.', 'suffix' => null);
$this->assertEquals($expected, $result);
}
