feat: add assignee check before composing conversation

app/listeners/notification_listener.rb

@@ -31,8 +31,11 @@ class NotificationListener < BaseListener
     conversation, account = extract_conversation_and_account(event)
     assignee = conversation.assignee
     return if event.data[:notifiable_assignee_change].blank?
+
     return if conversation.pending?
 
+    return if assignee.blank?
+
     NotificationBuilder.new(
       notification_type: 'conversation_assignment',
       user: assignee,

spec/listeners/notification_listener_spec.rb

@@ -155,4 +155,53 @@ describe NotificationListener do
       end
     end
   end
+
+  describe 'assignee_changed' do
+    let(:event_name) { :'conversation.assignee_changed' }
+
+    context 'when assignee is changed' do
+      it 'creates notifications for inbox members who have notifications turned on' do
+        notification_setting = first_agent.notification_settings.first
+        notification_setting.selected_email_flags = [:email_conversation_assignment]
+        notification_setting.selected_push_flags = []
+        notification_setting.save!
+
+        create(:inbox_member, user: first_agent, inbox: inbox)
+        conversation.reload
+
+        event = Events::Base.new(event_name, Time.zone.now, conversation: conversation, notifiable_assignee_change: true)
+
+        listener.assignee_changed(event)
+        expect(user.notifications.count).to eq(1)
+      end
+
+      it 'does not create notification for inbox members who have notifications turned off' do
+        notification_setting = agent_with_out_notification.notification_settings.first
+        notification_setting.unselect_all_email_flags
+        notification_setting.unselect_all_push_flags
+        notification_setting.save!
+
+        create(:inbox_member, user: agent_with_out_notification, inbox: inbox)
+        conversation.reload
+
+        event = Events::Base.new(event_name, Time.zone.now, conversation: conversation)
+
+        listener.assignee_changed(event)
+        expect(notification_setting.user.notifications.count).to eq(0)
+      end
+
+      it 'does not create notification when assignee is nil' do
+        create(:inbox_member, user: first_agent, inbox: inbox)
+        conversation.reload
+
+        conversation.assignee = nil
+        conversation.save!
+
+        event = Events::Base.new(event_name, Time.zone.now, conversation: conversation, notifiable_assignee_change: true, assignee: nil)
+
+        listener.assignee_changed(event)
+        expect(user.notifications.count).to eq(0)
+      end
+    end
+  end
 end