zammad/spec/factories/link.rb

FactoryBot.define do
  factory :link do
    transient do
      from { Ticket.first }
      to   { Ticket.last }
    end

    link_type_id             { Link::Type.find_by(name: 'normal').id }
    link_object_source_id    { Link::Object.find_by(name: 'Ticket').id }
    link_object_target_id    { Link::Object.find_by(name: 'Ticket').id }
    link_object_source_value { from.id }
    link_object_target_value { to.id }
  end
end