User Settings > Personal allows creation of invalid display names moi…

…nwiki#1707

docs/user/accounts.rst

@@ -65,8 +65,10 @@ Name
  Alias names are only useful at login.
 
 Display-Name
- The display name can be used to override your username, so you will still log in using your username
- but your display name will be displayed to other users and in your history page.
+ The display name can be used if a wiki's custom auth method creates cryptic user names.
+ You will still login using your username or alias, but your display-name will be used
+ instead of your name to create your home page in the users namespace. Links in history pages
+ and footers will use your display-name.
 
 Timezone
  Setting this value will display edit times converted to your local time zone. For

src/moin/apps/frontend/views.py

@@ -2455,6 +2455,18 @@ class UserSettingsUIForm(Form):
                                         )
                                     )
                                     success = False
+                        if form[DISPLAY_NAME]:
+                            display_name = str(form[DISPLAY_NAME])
+                            if not user.normalizeName(display_name) == display_name:
+                                response["flash"].append(
+                                    (
+                                        _("The displayname '{name}' contains invalid characters").format(
+                                            name=display_name
+                                        ),
+                                        "error",
+                                    )
+                                )
+                                success = False
                     if part == "notification":
                         if (
                             form["email"].value != flaskg.user.email

src/moin/themes/__init__.py

@@ -382,18 +382,17 @@ def userhome(self):
         :returns: arguments of user homepage link in tuple (wiki_href, display_name, title, exists)
         """
         user = self.user
-        name = user.name0
-        display_name = user.display_name or name
+        name = user.display_name or user.name0
         wikiname, itemname = getInterwikiHome(name)
-        title = f"{display_name} @ {wikiname}"
         # link to (interwiki) user homepage
         if is_local_wiki(wikiname):
             exists = self.storage.has_item(itemname)
         else:
             # We cannot check if wiki pages exists in remote wikis
             exists = True
         wiki_href = url_for_item(itemname, wiki_name=wikiname, namespace=NAMESPACE_USERS)
-        return wiki_href, display_name, title, exists
+        title = wiki_href
+        return wiki_href, name, title, exists
 
     def split_navilink(self, text):
         """
@@ -655,13 +654,13 @@ def get_editor_info(meta, external=False):
     if userid:
         u = user.User(userid)
         name = u.name0
+        name = u.display_name or name
         text = name
-        display_name = u.display_name or name
         if title:
             # we already have some address info
-            title = f"{display_name} @ {title}"
+            title = f"{name} @ {title}"
         else:
-            title = display_name
+            title = name
         if u.mailto_author and u.email:
             email = u.email
             css = "editor mail"