Changes after code-review (thanks @paroga)

app/controllers/concerns/auth.rb

@@ -56,16 +56,16 @@ def authenticate(role = 'any')
       # We have an authenticated user, now check role...
       # Roles gets the user through his memberships.
       hasRole = case role
-      when "admin"  then current_user.role_admin?
-      when "finance"   then  current_user.role_finance?
-      when "article_meta" then current_user.role_article_meta?
-      when "pickups" then current_user.role_pickups?
-      when "suppliers"  then current_user.role_suppliers?
-      when "orders" then current_user.role_orders?
-      when "finance_or_orders" then (current_user.role_finance? || current_user.role_orders?)
-      when "pickups_or_orders" then (current_user.role_pickups? || current_user.role_orders?)
-      when "any" then true        # no role required
-      else false                  # any unknown role will always fail
+      when 'admin'             then current_user.role_admin?
+      when 'finance'           then current_user.role_finance?
+      when 'article_meta'      then current_user.role_article_meta?
+      when 'pickups'           then current_user.role_pickups?
+      when 'suppliers'         then current_user.role_suppliers?
+      when 'orders'            then current_user.role_orders?
+      when 'finance_or_orders' then (current_user.role_finance? || current_user.role_orders?)
+      when 'pickups_or_orders' then (current_user.role_pickups? || current_user.role_orders?)
+      when 'any'               then true  # no role required
+      else false                          # any unknown role will always fail
       end
       if hasRole
         current_user

app/controllers/concerns/locale.rb

@@ -10,7 +10,7 @@ def explicitly_requested_language
   end
 
   def user_settings_language
-    current_user.locale if current_user
+    current_user&.locale
   end
 
   def session_language
@@ -30,7 +30,7 @@ def default_language
   def select_language_according_to_priority
     language = explicitly_requested_language || session_language || user_settings_language
     language ||= browser_language unless FoodsoftConfig[:ignore_browser_locale]
-    language.to_sym unless language.blank?
+    language.presence&.to_sym unless language.blank?
   end
 
   def available_locales

config/application.rb

@@ -63,11 +63,11 @@ class Application < Rails::Application
     config.assets.precompile += [ 'vendor/assets/javascripts/*.js' ]
 
     # CORS for API
-    config.middleware.insert_before 0, "Rack::Cors" do
+    config.middleware.insert_before 0, 'Rack::Cors' do
       allow do
         origins '*'
         # this restricts Foodsoft scopes to certain characters - let's discuss it when it becomes an actual problem
-        resource %r{\A/[-a-zA-Z0-9_]+/api/v1/}, :headers => :any, :methods => :any
+        resource %r{\A/[-a-zA-Z0-9_]+/api/v1/}, headers: :any, methods: :any
       end
     end
   end

config/locales/de.yml

@@ -663,6 +663,7 @@ de:
       use_wiki: Wiki verwenden
       webstats_tracking_code: Code für Websiteanalysetool
     tabs:
+      applications: Apps
       foodcoop: Foodcoop
       language: Sprache
       layout: Layout