Genshin/GAKUEngine

module Semesterable
  extend ActiveSupport::Concern

  included do
    has_many :semester_connectors, as: :semesterable, dependent: :destroy
    has_many :semesters, through: :semester_connectors, source: :semester

    scope :without_semester,
          -> { includes(:semester_connectors).where(gaku_semester_connectors: { semesterable_id: nil }) }
  end
end