def METHOD_NAME(get_users_by_mock):
    target_user = "testuser"
    command = craft_command(
        command_data=GPGEncryptCommandData(
            vault_secret_path="/tmp/tmp",
            target_user=target_user,
        ),
        secret={},
    )
    get_users_by_mock.side_effect = [[]]
    with pytest.raises(UserException) as exc:
        command.execute()
    assert "Expected to find exactly one user" in str(exc.value)