UX: when admin is deleted, make it clear in staff action logs when records belong to a deleted user and show their username in the details

app/assets/javascripts/admin/templates/logs/staff-action-logs.hbs

@@ -32,7 +32,7 @@
   {{else}}
     {{i18n "admin.logs.staff_actions.filter"}} {{combo-box content=userHistoryActions value=filterActionId none="admin.logs.staff_actions.all"}}
   {{/if}}
-  
+
   {{d-button action="exportStaffActionLogs" label="admin.export_csv.button_text" icon="download"}}
 </div>
 <div class="clearfix"></div>
@@ -57,8 +57,14 @@
       <tr class='admin-list-item'>
         <td class="staff-users">
           <div class="staff-user">
-          {{#link-to 'adminUser' item.acting_user}}{{avatar item.acting_user imageSize="tiny"}}{{/link-to}}
-          <a {{action "filterByStaffUser" item.acting_user}}>{{item.acting_user.username}}</a>
+            {{#if item.acting_user}}
+              {{#link-to 'adminUser' item.acting_user}}{{avatar item.acting_user imageSize="tiny"}}{{/link-to}}
+              <a {{action "filterByStaffUser" item.acting_user}}>{{item.acting_user.username}}</a>
+            {{else}}
+              <span class="deleted-user" title="{{i18n 'admin.user.deleted'}}">
+                {{d-icon "trash-o"}}
+              </span>
+            {{/if}}
           </div>
         </td>
         <td class="col value action">

app/assets/stylesheets/common/admin/staff_logs.scss

@@ -163,6 +163,9 @@
     a:first-of-type {
       margin-right: 0.25em;
     }
+    .deleted-user {
+      font-size: $font-up-2;
+    }
   }
   .created_at {
     text-align: center;

app/services/user_destroyer.rb

@@ -49,6 +49,17 @@ class UserDestroyer
         post_action.remove_act!(Discourse.system_user)
       end
 
+      # Add info about the user to staff action logs
+      UserHistory.staff_action_records(
+        Discourse.system_user, acting_user: user.username
+      ).each do |log|
+        log.details ||= ''
+        log.details = (log.details.split("\n") +
+            ["user_id: #{user.id}", "username: #{user.username}"]
+          ).join("\n")
+        log.save!
+      end
+
       # keep track of emails used
       user_emails = user.user_emails.pluck(:email)
 

spec/services/user_destroyer_spec.rb

@@ -360,6 +360,28 @@ describe UserDestroyer do
         }.to change { User.count }.by(-1)
       end
     end
+
+    context 'user has staff action logs' do
+      before do
+        logger = StaffActionLogger.new(user)
+        logger.log_site_setting_change(
+          'site_description',
+          'Our friendly community',
+          'My favourite community'
+        )
+      end
+
+      it "should keep the staff action log and add the username" do
+        username = user.username
+        log = UserHistory.staff_action_records(
+          Discourse.system_user,
+          acting_user: username
+        ).to_a[0]
+        UserDestroyer.new(admin).destroy(user, delete_posts: true)
+        log.reload
+        expect(log.details).to include(username)
+      end
+    end
   end
 
 end