add tests

fsd_utils/locale_selector/set_lang.py

@@ -36,7 +36,6 @@ def __init__(self, app):
     @staticmethod
     def select_language(locale):
         referrer = request.referrer or "/"
-        referrer = referrer.replace("\\", "/")
         if not urlparse(referrer).netloc and not urlparse(referrer).scheme:
             response = make_response(redirect(referrer, 302))
         else:

tests/test_set_lang.py

@@ -13,3 +13,25 @@ def test_set_lang(flask_test_client):
         response_cookie = response.headers.get("Set-Cookie")
         assert response_cookie is not None, "No cookie set for language"
         assert response_cookie.split(";")[0] == ("language" + "=cy")
+
+
+def test_set_lang_referrer_ignores_external_referrer(flask_test_client):
+    mock_app = Mock()
+    set_lang = LanguageSelector(mock_app)
+    mock_app.add_url_rule.assert_called_with("/language/<locale>", view_func=ANY)
+    with flask_test_client.application.test_request_context(
+        headers={"Referer": "http://example.com/foo"}
+    ):
+        response = set_lang.select_language("cy")
+        assert response.location == "/"
+
+
+def test_set_lang_follows_internal_referrer(flask_test_client):
+    mock_app = Mock()
+    set_lang = LanguageSelector(mock_app)
+    mock_app.add_url_rule.assert_called_with("/language/<locale>", view_func=ANY)
+    with flask_test_client.application.test_request_context(
+        headers={"Referer": "localhost/foo"}
+    ):
+        response = set_lang.select_language("cy")
+        assert response.location == "localhost/foo"