Can't pass mysqli object to class in PHP - php

Question

So I'm working on a simple user class in php, which has a class variable which contains the mysqli object, however I keep getting the error:
Fatal error: Call to a member function real_escape_string() on a non-object in */classes/user.php on line X
I've checked everything, it should work, but it doesn't. Somehow. This is my code:
namespace bibliotheek;
class user
{
private $mysql;
private $logged_in = false;
private $user_data = null; //ARRAY: user_id, e-mail, password, bevoegdheid, naam, achternaam, adres, postcode, stad
function __construct(\mysqli $mysql, $salt)
{
$this->mysql = $mysql;
}
public function login($email, $pass, $hash = false)
{
$email = $this->mysql->real_escape_string($email);
if($hash == false)
$pass = sha1($this->salt.$pass);
$query = "SELECT *
FROM gebruikers
WHERE gebruikers.email = '$email' AND gebruikers.password = '$pass'";
$result = $this->mysql->query($query);
$user_data = $result->fetch_assoc();
if($user_data == null)
return;
$this->logged_in = true;
$this->user_data = $user_data;
$this->create_cookies($email, $pass);
}
}
And this is how the mysqli object gets passed to the class:
$mysql = new mysqli($cfg['mysql_server'], $cfg['username'], $cfg['password'], $cfg['database']);
$user = new bibliotheek\user($mysql, $cfg['salt']);
the mysql login data is correct, I've made sure of that.
I must be missing something really obvious here, but I just can't see it. Any help is greatly appreciated. Thanks!

Answer 1

And this is how it should be
error_reporting(E_ALL);
$mysql = new mysqli($cfg['mysql_server'], $cfg['username'], $cfg['password'], $cfg['database']);
if ( !$mysql )
{
throw new Exception(mysqli_connect_error()));
}
$user = new bibliotheek\user($mysql, $cfg['salt']);

Answer 2

I'm really f-ing stupid, I compacted my code a bit when I posted it on here and I left out this part:
$this->mysql = $mysql;
$this->mysql = $salt;
Kill me now.