app/models/story.rb
class Story < ApplicationRecord
include DateValidationHelper
belongs_to :sprint
validates :name, presence: true, length: { maximum: 128, minimum: 2 }
validates :description, length: { maximum: 8000 }
validates :assign, length: { maximum: 32, minimum: 2 }, allow_blank: true
validates :pipeline, length: { maximum: 16, minimum: 4 }
validates :initial_date, presence: true
validates :issue_number, presence: true
validate :is_final_date_valid?
end