Introduce `has-sub-items` class to top links

lib/sidebars/menu.rb

@@ -83,6 +83,17 @@ module Sidebars
       insert_element_after(@items, after_item, new_item)
     end
 
+    override :container_html_options
+    def container_html_options
+      super.tap do |html_options|
+        # Flagging menus that can be rendered but without any children
+        # like the merge requests or the requirements menu
+        if render? && has_renderable_items?
+          html_options[:class] = [*html_options[:class], 'has-sub-items'].join(' ')
+        end
+      end
+    end
+
     private
 
     override :index_of

lib/sidebars/projects/menus/scope_menu.rb

@@ -34,6 +34,11 @@ module Sidebars
 
           { class: 'context-header' }
         end
+
+        override :render?
+        def render?
+          true
+        end
       end
     end
   end

spec/lib/sidebars/menu_spec.rb

@@ -144,4 +144,56 @@ RSpec.describe Sidebars::Menu do
       end
     end
   end
+
+  describe '#container_html_options' do
+    before do
+      allow(menu).to receive(:title).and_return('Foo Menu')
+    end
+
+    context 'when menu can be rendered' do
+      before do
+        allow(menu).to receive(:render?).and_return(true)
+      end
+
+      context 'when menu has renderable items' do
+        before do
+          allow(menu).to receive(:has_renderable_items?).and_return(true)
+        end
+
+        it 'contains the special class' do
+          menu.add_item(Sidebars::MenuItem.new(title: 'foo1', link: 'foo1', active_routes: { path: 'bar' }))
+
+          expect(menu.container_html_options[:class]).to eq 'has-sub-items'
+        end
+
+        context 'when menu already has other classes' do
+          it 'appends special class' do
+            allow(menu).to receive(:extra_container_html_options).and_return(class: 'foo')
+
+            expect(menu.container_html_options[:class]).to eq 'foo has-sub-items'
+          end
+        end
+      end
+
+      context 'when menu does not have renderable items' do
+        before do
+          allow(menu).to receive(:has_renderable_items?).and_return(false)
+        end
+
+        it 'does not contain the special class' do
+          expect(menu.container_html_options[:class]).to be_nil
+        end
+      end
+    end
+
+    context 'when menu cannot be rendered' do
+      before do
+        allow(menu).to receive(:render?).and_return(false)
+      end
+
+      it 'does not contain "has-sub-items" class' do
+        expect(menu.container_html_options[:class]).to be_nil
+      end
+    end
+  end
 end