fix: Redirect after authentication on http://localhost without /

* fix: manage root path properly when we join them

src/writer/auth.py

@@ -339,14 +339,17 @@ def urljoin(*args):
     >>> "app1/edit"
 
     >>> urljoin("/app1/", "/edit")
-    >>> "app1/edit"
+    >>> "/app1/edit"
     """
+    root_part = args[0]
+    root_part_is_root_path = root_part.startswith('/') and len(root_part) > 1
+
     url_strip_parts = []
     for part in args:
         if part:
             url_strip_parts.append(urlstrip(part))
 
-    return '/'.join(url_strip_parts)
+    return '/'.join(url_strip_parts) if root_part_is_root_path is False else '/' + '/'.join(url_strip_parts)
 
 def urlstrip(url_path: str):
     """

tests/backend/test_auth.py

@@ -43,7 +43,8 @@ def test_basicauth_authentication_module_disabled_when_server_setup_hook_is_disa
         ("http://localhost", "/"),
         ("http://localhost/", "/"),
         ("http://localhost/any", "/any"),
-        ("http://localhost/any/", "/any/")
+        ("http://localhost/any/", "/any/"),
+        ("/any/yolo", "/any/yolo")
     ])
     def test_url_path_scenarios(self, path: str, expected_path: str):
         assert auth.urlpath(path) == expected_path
@@ -63,6 +64,8 @@ def test_url_split_scenarios(self, path: str, expected_path: str):
     @pytest.mark.parametrize("path1,path2,expected_path", [
         ("/", "any", "/any"),
         ("", "any", "any"),
+        ("/yolo", "any", "/yolo/any"),
+        ("/yolo", "/any", "/yolo/any"),
         ("http://localhost", "any", "http://localhost/any"),
         ("http://localhost/", "/any", "http://localhost/any"),
         ("http://localhost/yolo", "/any", "http://localhost/yolo/any"),