module ActiveModel
module Validations
module ClassMethods
# Encapsulates the pattern of wanting to validate a password or email address field with a confirmation. Example:
#
# Model:
# class Person < ActiveRecord::Base
# validates_confirmation_of :user_name, :password
# validates_confirmation_of :email_address, :message => "should match confirmation"
# end
#
# View:
# <%= password_field "person", "password" %>
# <%= password_field "person", "password_confirmation" %>
#
# The added +password_confirmation+ attribute is virtual; it exists only as an in-memory attribute for validating the password.
# To achieve this, the validation adds accessors to the model for the confirmation attribute. NOTE: This check is performed
# only if +password_confirmation+ is not +nil+, and by default only on save. To require confirmation, make sure to add a presence
# check for the confirmation attribute:
#
# validates_presence_of :password_confirmation, :if => :password_changed?
#
# Configuration options:
# * <tt>:message</tt> - A custom error message (default is: "doesn't match confirmation").
# * <tt>:on</tt> - Specifies when this validation is active (default is <tt>:save</tt>, other options <tt>:create</tt>, <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.
def validates_confirmation_of(*attr_names)
configuration = attr_names.extract_options!
attr_accessor(*(attr_names.map { |n| "#{n}_confirmation" }))
validates_each(attr_names, configuration) do |record, attr_name, value|
unless record.send("#{attr_name}_confirmation").nil? or value == record.send("#{attr_name}_confirmation")
record.errors.add(attr_name, :confirmation, :default => configuration[:message])
end
end
end
end
end
end
