PyTest expected exceptions (bank deposit) - no exception happens

Pytest properly reports that there was no exception where an exception was expected.

class NegativeDeposite(Exception):
    pass

class Bank:
    def __init__(self, start):
        self.balance = start

    def deposit(self, money):
        #if money < 0:
        #    raise NegativeDeposite('Cannot deposit negative sum')
        self.balance += money
        return

    def test_negative_deposit():
        b = Bank(10)
        with pytest.raises(NegativeDeposite) as e:
>           b.deposit(-1)
E           Failed: DID NOT RAISE <class 'Exception'>