Test related question (Testing redirection to login page on autogenerated user auth tests)

Questions / Help
1

Hello, I am trying to update tests that come with phoenix autogenerated auth layer, specifically on this function

def on_mount(:ensure_authenticated, _params, session, socket) do
    socket = mount_current_user(socket, session)

    if socket.assigns.current_user do
      {:cont, socket}
    else
      socket =
        socket
        |> Phoenix.LiveView.put_flash(:error, "You must log in to access this page.")
        |> Phoenix.LiveView.redirect(to: ~p"/login")

      {:halt, socket}
    end
  end

and its tests:

describe "on_mount: ensure_authenticated" do
    test "redirects to login page if there isn't a valid user_token", %{conn: conn} do
      user_token = "invalid_token"
      session = conn |> put_session(:user_token, user_token) |> get_session()

      socket = %LiveView.Socket{
        endpoint: EasyBillsWeb.Endpoint,
        assigns: %{__changed__: %{}, flash: %{}}
      }

      {:halt, updated_socket} = UserAuth.on_mount(:ensure_authenticated, %{}, session, socket)
      assert updated_socket.assigns.current_user == nil

      assert updated_socket.assigns.flash["error"] == "You must log in to access this page."
      assert redirected_to(updated_socket) == ~p"/login"
    end

    test "redirects to login page if there isn't a user_token", %{conn: conn} do
      session = conn |> get_session()

      socket = %LiveView.Socket{
        endpoint: EasyBillsWeb.Endpoint,
        assigns: %{__changed__: %{}, flash: %{}}
      }

      {:halt, updated_socket} = UserAuth.on_mount(:ensure_authenticated, %{}, session, socket)
      #failing
      assert updated_socket.assigns.current_user == nil

      assert updated_socket.assigns.flash["error"] == "You must log in to access this page."
      #failing
      assert redirected_to(updated_socket) == ~p"/login"
    end
  end

I want to test the redirection happens back to login page. Above, I have added two tests lines in each test block, the flash error assertion and the next line to assert the redirection happens which is failing.

I realise I can’t use redirected_to/2 with socket as I would with conn, which limits me only to test the presence of specific data in the socket.assigns or flash messages.
But I would wish to assert that the redirection happened.

Any help achieving this will be appreciated.
Thanks.