FEATURE: auto archive group message if topic is closed. (#9046)

Co-Authored-By: Régis Hanol <regis@hanol.fr>

app/models/topic.rb

@@ -502,6 +502,17 @@ class Topic < ActiveRecord::Base
   def update_status(status, enabled, user, opts = {})
     TopicStatusUpdater.new(self, user).update!(status, enabled, opts)
     DiscourseEvent.trigger(:topic_status_updated, self, status, enabled)
+
+    if enabled && private_message? && status.to_s["closed"]
+      group_ids = user.groups.pluck(:id)
+      if group_ids.present?
+        allowed_group_ids = self.allowed_groups
+          .where('topic_allowed_groups.group_id IN (?)', group_ids).pluck(:id)
+        allowed_group_ids.each do |id|
+          GroupArchivedMessage.archive!(id, self)
+        end
+      end
+    end
   end
 
   # Atomically creates the next post number

spec/models/topic_spec.rb

@@ -1114,6 +1114,14 @@ describe Topic do
     context 'closed' do
       let(:status) { 'closed' }
       it_should_behave_like 'a status that closes a topic'
+
+      it 'should archive group message' do
+        group = Fabricate(:group)
+        group.add(@user)
+        topic = Fabricate(:private_message_topic, allowed_groups: [group])
+
+        expect { topic.update_status(status, true, @user) }.to change(topic.group_archived_messages, :count).by(1)
+      end
     end
 
     context 'autoclosed' do