Rewrite group nav_left sheet to work also in specs

refs hitobito/hitobito_sac_cas#523

app/helpers/sheet/group/nav_left.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-#  Copyright (c) 2014-2021 Pfadibewegung Schweiz. This file is part of
+#  Copyright (c) 2014-2024 Pfadibewegung Schweiz. This file is part of
 #  hitobito and licensed under the Affero General Public License version 3
 #  or later. See the COPYING file at the top-level directory or at
 #  https://github.com/hitobito/hitobito.
@@ -117,15 +117,19 @@ def render_deleted_people_link
       end
 
       def render_sub_layers
-        safe_join(grouped_sub_layers) do |type, layers|
+        layers = grouped_sub_layers.map do |type, layers|
           content_tag(:li, content_tag(:span, type, class: 'divider')) +
-          safe_join(layers.map { |l| GroupDecorator.new(l) }) do |l|
-            l.use_hierarchy_from_parent(layer)
-            content_tag(:li, class: l.archived_class) do
-              link_to(l.display_name, active_path(l),
-                      title: l.to_s, data: { turbo_submits_with: l.display_name })
-            end
-          end
+            safe_join(layers.map { |l| render_sub_layer(l.decorate)  })
+
+        end
+        safe_join(layers)
+      end
+
+      def render_sub_layer(l)
+        l.use_hierarchy_from_parent(layer)
+        content_tag(:li, class: l.archived_class) do
+          link_to(l.display_name, active_path(l),
+                  title: l.to_s, data: { turbo_submits_with: l.display_name })
         end
       end
 

spec/helpers/sheet/group/nav_left_spec.rb

@@ -1,4 +1,4 @@
-#  Copyright (c) 2012-2014, Pfadibewegung Schweiz. This file is part of
+#  Copyright (c) 2012-2024, Pfadibewegung Schweiz. This file is part of
 #  hitobito and licensed under the Affero General Public License version 3
 #  or later. See the COPYING file at the top-level directory or at
 #  https://github.com/hitobito/hitobito.
@@ -46,11 +46,9 @@ def can?(*_args)
       is_expected.to_not have_link('TP', text: 'TP')
     end
 
-    # TODO: safe_join of this test's view does not behave as it should
-    # it 'displays sub layer with short name if available' do
-    #   is_expected.to have_link('One', text: 'One')
-    #   is_expected.to_not have_link('Bottom One', text: 'Bottom One')
-    # end
+    it 'displays sub layer' do
+      is_expected.to have_link('Bottom One', text: 'Bottom One')
+    end
 
     it 'displays group with short name if available' do
       is_expected.to have_link('TG', text: 'TG')