zammad/spec/models/ticket_spec.rb

require 'rails_helper'

RSpec.describe Ticket do

  describe '.merge_to' do

    it 'reassigns all links to the target ticket after merge' do
      source_ticket     = create(:ticket)
      target_ticket     = create(:ticket)

      important_ticket1 = create(:ticket)
      important_ticket2 = create(:ticket)
      important_ticket3 = create(:ticket)

      create(:link, link_object_source_value: source_ticket.id, link_object_target_value: important_ticket1.id)
      create(:link, link_object_source_value: source_ticket.id, link_object_target_value: important_ticket2.id)
      create(:link, link_object_source_value: source_ticket.id, link_object_target_value: important_ticket3.id)

      source_ticket.merge_to(
        ticket_id: target_ticket.id,
        user_id:   1,
      )

      links = Link.list(
        link_object: 'Ticket',
        link_object_value: target_ticket.id,
      )

      expected_ticket_ids = [source_ticket.id, important_ticket1.id, important_ticket2.id, important_ticket3.id ]
      check_ticket_ids    = links.collect { |link| link['link_object_value'] }

      expect(check_ticket_ids).to match_array(expected_ticket_ids)
    end
  end
end