Don't leave user in limbo if they change their username

ckan/lib/base.py

@@ -195,12 +195,17 @@ def _identify_user(self):
             c.userobj = model.User.by_name(c.user)
             if c.userobj is None:
                 # This occurs when you are logged in, clean db
-                # and then restart i.e. only really for testers. There is no
-                # user object, so even though repoze thinks you are logged in
-                # and your cookie has ckan_display_name, we need to force user
-                # to logout and login again to get the User object.
-                c.user = None
-                self.log.warn('Logout to login')
+                # and then restart (or when you change your username)
+                # There is no user object, so even though repoze thinks you
+                # are logged in and your cookie has ckan_display_name, we
+                # need to force user to logout and login again to get the
+                # User object.
+                session['lang'] = request.environ.get('CKAN_LANG')
+                session.save()
+
+                pth = getattr(request.environ['repoze.who.plugins']\
+                    ['friendlyform'], 'logout_handler_path')
+                h.redirect_to(pth)
         else:
             c.userobj = self._get_user_for_apikey()
             if c.userobj is not None:

ckan/templates/user/edit_user_form.html

@@ -1,6 +1,6 @@
-<form 
-  id="user-edit" 
-  action="" 
+<form
+  id="user-edit"
+  action=""
   method="post"
   class="form-horizontal ${'has-errors' if errors else ''}"
   xmlns:i18n="http://genshi.edgewall.org/i18n"
@@ -63,6 +63,7 @@ <h2>Errors in form</h2>
       <label for="name" class="control-label">Username</label>
       <div class="controls">
         <input type="text" name="name" value="${data.get('name','')}" />
+        <p>Changing your username will log you out, and require you to log back in with the new username</p>
       </div>
     </div>
   </fieldset>