def METHOD_NAME(self, context):
    context.path = 'facebook/sso/redirect'
    internal_request = InternalData(
        subject_type=NAMEID_FORMAT_TRANSIENT, requester='test_requester'
    )
    resp = self.fb_backend.start_auth(context, internal_request, mock_get_state)
    login_url = resp.message
    assert login_url.startswith(FB_AUTH_ENDPOINT)
    expected_params = {
        "client_id": CLIENT_ID,
        "state": mock_get_state.return_value,
        "response_type": "code",
        "redirect_uri": "%s/%s" % (BASE_URL, AUTHZ_PAGE)
    }
    actual_params = dict(parse_qsl(urlparse(login_url).query))
    assert actual_params == expected_params