1
0
Fork 0
mirror of https://github.com/rails/rails.git synced 2022-11-09 12:12:34 -05:00
rails--rails/activerecord/test/models/lesson.rb
2017-07-19 22:27:07 +03:00

13 lines
254 B
Ruby

# frozen_string_literal: true
class LessonError < Exception
end
class Lesson < ActiveRecord::Base
has_and_belongs_to_many :students
before_destroy :ensure_no_students
def ensure_no_students
raise LessonError unless students.empty?
end
end