def test_add_user_returns_none_on_failure(self):
        self.user.status = FAILED
        self.stub.AddUser.return_value = self.user

        client_stub = ClientStub(stub=self.stub)
        assert client_stub.add_user("Test") is None
    def test_add_user(self):
        self.user.status = SUCCESS
        self.stub.AddUser.return_value = self.user

        client_stub = ClientStub(stub=self.stub)
        assert client_stub.add_user("Test") == self.user