Hide super admin menu items for enterprise users

Imported temporarily missing Spree functionality. This patch becomes
obsolete with another Spree upgrade.

app/helpers/spree/admin/navigation_helper_decorator.rb

@@ -1,6 +1,15 @@
 module Spree
   module Admin
     module NavigationHelper
+      # TEMP: import method until it is re-introduced into Spree.
+      def klass_for(name)
+        model_name = name.to_s
+
+        ["Spree::#{model_name.classify}", model_name.classify, model_name.gsub('_', '/').classify].find do |t|
+          t.safe_constantize
+        end.try(:safe_constantize)
+      end
+
       # Make it so that the Reports admin tab can be enabled/disabled through the cancan
       # :report resource, since it does not have a corresponding resource class (unlike
       # eg. Spree::Product).
@@ -12,6 +21,17 @@ module Spree
       #   klass
       # end
       # alias_method_chain :klass_for, :sym_fallback
+
+      # TEMP: override method until it is fixed in Spree.
+      def tab_with_cancan_check(*args)
+        options = {:label => args.first.to_s}
+        if args.last.is_a?(Hash)
+          options = options.merge(args.last)
+        end
+        return '' if klass = klass_for(options[:label]) and cannot?(:admin, klass)
+        tab_without_cancan_check(*args)
+      end
+      alias_method_chain :tab, :cancan_check
     end
   end
 end

spec/features/admin/authentication_spec.rb

@@ -18,6 +18,7 @@ feature "Authentication", js: true do
       click_login_button
       expect(page).to have_content "DASHBOARD"
       expect(page).to have_current_path spree.admin_path
+      expect(page).to have_no_content "CONFIGURATION"
     end
   end