Solution to ActiveRecord Validations homework

gistfile1.rb

class Cat < ActiveRecord::Base
  attr_accessible :birthdate, :breed, :name

  BREEDS = [:arabean, :asian, :bengal, :persian]

  # Name must be present and between 5 and 20 characters
  validates :name, length: { in: 5..20 }

  # Breed must be one of the following: :arabean, :asian, :bengal, :persian 
  validates :breed, inclusion: { in: BREEDS }

  # Birthdate must be after 'today' (Date.today) and cat must not be older than 20 years.
  validate :valid_birthdate

  def valid_birthdate
    if birthdate
      errors.add(:birthday, "Must be in the past") if birthdate > Date.today
      errors.add(:birthday, "Age must be below 20 years") if birthdate < 20.years.ago
    end
  end

  # Valid cat:
  # Cat.create! name: 'Kipod', breed: :persian, birthdate: 3.years.ago
end