Rearrange the tests and add another case where

it would still render the sidebar whenever the wiki is empty.

spec/features/projects/wiki/user_creates_wiki_page_spec.rb

@@ -249,7 +249,18 @@ describe 'User creates wiki page' do
     end
   end
 
-  context 'when wiki has two pages' do
+  describe 'sidebar feature' do
+    context 'when the wiki is empty' do
+      it 'renders my customized sidebar' do
+        create(:wiki_page, wiki: wiki, attrs: { title: '_sidebar', content: 'My customized sidebar' })
+
+        visit(project_wikis_path(project))
+
+        expect(page).to have_content('My customized sidebar')
+      end
+    end
+
+    context 'when there are some existing pages' do
       before do
         create(:wiki_page, wiki: wiki, attrs: { title: 'home', content: 'home' })
         create(:wiki_page, wiki: wiki, attrs: { title: 'another', content: 'another' })
@@ -276,4 +287,5 @@ describe 'User creates wiki page' do
         end
       end
     end
+  end
 end