class UserRole < ActiveRecord::Base
belongs_to :user
+ belongs_to :granter, :class_name => "User"
- ALL_ROLES = ['administrator', 'moderator']
+ ALL_ROLES = %w[administrator moderator].freeze
- validates_inclusion_of :role, :in => ALL_ROLES
- validates_uniqueness_of :role, :scope => :user_id
+ validates :role, :inclusion => ALL_ROLES, :uniqueness => { :scope => :user_id }
end