require 'active_support/core_ext/object/blank' module ActiveModel # == Active Model Presence Validator module Validations class PresenceValidator < EachValidator def validate(record) record.errors.add_on_blank(attributes, options) end end module HelperMethods # Validates that the specified attributes are not blank (as defined by Object#blank?). Happens by default on save. Example: # # class Person < ActiveRecord::Base # validates_presence_of :first_name # end # # The first_name attribute must be in the object and it cannot be blank. # # If you want to validate the presence of a boolean field (where the real values are true and false), # you will want to use <tt>validates_inclusion_of :field_name, :in => [true, false]</tt>. # # This is due to the way Object#blank? handles boolean values: <tt>false.blank? # => true</tt>. # # Configuration options: # * <tt>:message</tt> - A custom error message (default is: "can't be blank"). # * <tt>:on</tt> - Specifies when this validation is active. Runs in all # validation contexts by default (+nil+), other options are <tt>:create</tt> # and <tt>:update</tt>. # * <tt>:if</tt> - Specifies a method, proc or string to call to determine if the validation should # occur (e.g. <tt>:if => :allow_validation</tt>, or <tt>:if => Proc.new { |user| user.signup_step > 2 }</tt>). # The method, proc or string should return or evaluate to a true or false value. # * <tt>:unless</tt> - Specifies a method, proc or string to call to determine if the validation should # not occur (e.g. <tt>:unless => :skip_validation</tt>, or <tt>:unless => Proc.new { |user| user.signup_step <= 2 }</tt>). # The method, proc or string should return or evaluate to a true or false value. # * <tt>:strict</tt> - Specifies whether validation should be strict. # See <tt>ActiveModel::Validation#validates!</tt> for more information # def validates_presence_of(*attr_names) validates_with PresenceValidator, _merge_attributes(attr_names) end end end end