Render the proper value so that the table sorts correctly by last edited

app/views/collections/_dataset_table.html.erb

@@ -25,7 +25,8 @@
               <span title="<%= ds.curator&.display_name %>"><%= ds.curator&.uid %></span>
           </td>
           <td><%= ds.state %></td>
-          <td>
+          <!-- see https://datatables.net/manual/data/orthogonal-data for sorting options -->
+          <td class="last-edited" data-sort="<%= ds.updated_at %>">
             <span title="<%= ds.updated_at.localtime %>"><%= distance_of_time_in_words_to_now(ds.updated_at) %></span>
           </td>
         </tr>

app/views/users/_dataset_table.html.erb

@@ -25,7 +25,8 @@
               <span title="<%= ds.curator&.display_name %>"><%= ds.curator&.uid %></span>
           </td>
           <td><%= ds.state %></td>
-          <td>
+          <!-- see https://datatables.net/manual/data/orthogonal-data for sorting options -->
+          <td class="last-edited" data-sort="<%= ds.updated_at %>">
             <span title="<%= ds.updated_at.localtime %>"><%= distance_of_time_in_words_to_now(ds.updated_at) %></span>
           </td>
         </tr>

spec/system/user_show_spec.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+require "rails_helper"
+RSpec.describe "User dashboard" do
+  describe "Sort by last edited uses the proper value" do
+    let(:user_admin) { FactoryBot.create :super_admin_user }
+    let(:work) { FactoryBot.create(:draft_work) }
+
+    it "renders the proper date value for sorting by last edited", js: true do
+      work_last_edited = work.updated_at.strftime("%Y-%m-%d %H:%M:%S %Z")
+      sort_value = '<td class="last-edited" data-sort="' + work_last_edited + '">'
+      sign_in user_admin
+      visit user_path(user_admin)
+      expect(page.html.include?(sort_value)).to be true
+    end
+  end
+end