Improved observer for better testing.

app/models/observer/ticket/article/fillup_from_email.rb

@@ -26,9 +26,11 @@ class Observer::Ticket::Article::FillupFromEmail < ActiveRecord::Observer
     # clean subject
     record.subject = ticket.subject_clean( record.subject )
 
-    # generate message id
+    # generate message id, force it in prodution, in test allow to set it for testing reasons
+    if !record.message_id || Rails.env.production?
       fqdn = Setting.get('fqdn')
       record.message_id = '<' + DateTime.current.to_s(:number) + '.' + record.ticket_id.to_s + '.' + rand(999_999).to_s() + '@' + fqdn + '>'
+    end
 
     # generate message_id_md5
     record.check_message_id_md5

test/unit/email_process_test.rb

@@ -2038,9 +2038,9 @@ Some Text',
       ticket_id: ticket.id,
       from: 'some_sender@example.com',
       to: 'some_recipient@example.com',
-      subject: 'some subject',
+      subject: 'bounce check',
       message_id: '<20150830145601.30.608881@edenhofer.zammad.com>',
-      body: 'some message article',
+      body: 'some message bounce check',
       internal: false,
       sender: Ticket::Article::Sender.where(name: 'Agent').first,
       type: Ticket::Article::Type.where(name: 'email').first,