fix(users): fix broken email fallback

src/Foundation.hs

@@ -3366,7 +3366,11 @@ upsertCampusUser ldapData Creds{..} = do
 
   let
     userMatrikelnummer' = fold [ v | (k, v) <- ldapData, k == ldapUserMatriculation ]
-    userEmail'          = fold [ v | (k, v) <- ldapData, k' <- toList ldapUserEmail, k' == k ]
+    userEmail'          = fold $ do
+      k' <- toList ldapUserEmail
+      (k, v) <- ldapData
+      guard $ k' == k
+      return v
     userDisplayName''   = fold [ v | (k, v) <- ldapData, k == ldapUserDisplayName   ]
     userFirstName'      = fold [ v | (k, v) <- ldapData, k == ldapUserFirstName     ]
     userSurname'        = fold [ v | (k, v) <- ldapData, k == ldapUserSurname       ]
@@ -3379,8 +3383,7 @@ upsertCampusUser ldapData Creds{..} = do
     userLastAuthentication = now <$ guard (not isDummy)
 
   userEmail <- if
-    | bs : _ <- userEmail'
-    , Right userEmail <- Text.decodeUtf8' bs
+    | userEmail : _ <- mapMaybe (assertM (elem '@') . either (const Nothing) Just . Text.decodeUtf8') userEmail'
       -> return $ mk userEmail
     | otherwise
       -> throwM CampusUserInvalidEmail