require 'active_support/core_ext/range'
module ActiveModel
# == Active Model Exclusion Validator
module Validations
class ExclusionValidator < EachValidator
ERROR_MESSAGE = "An object with the method #include? or a proc or lambda is required, " <<
"and must be supplied as the :in (or :within) option of the configuration hash"
def check_validity!
unless [:include?, :call].any? { |method| delimiter.respond_to?(method) }
raise ArgumentError, ERROR_MESSAGE
end
end
def validate_each(record, attribute, value)
exclusions = delimiter.respond_to?(:call) ? delimiter.call(record) : delimiter
if exclusions.send(inclusion_method(exclusions), value)
record.errors.add(attribute, :exclusion, options.except(:in, :within).merge!(:value => value))
end
end
private
def delimiter
@delimiter ||= options[:in] || options[:within]
end
# In Ruby 1.9 <tt>Range#include?</tt> on non-numeric ranges checks all possible
# values in the range for equality, so it may be slow for large ranges. The new
# <tt>Range#cover?</tt> uses the previous logic of comparing a value with the
# range endpoints.
def inclusion_method(enumerable)
enumerable.is_a?(Range) ? :cover? : :include?
end
end
module HelperMethods
# Validates that the value of the specified attribute is not in a particular
# enumerable object.
#
# class Person < ActiveRecord::Base
# validates_exclusion_of :username, :in => %w( admin superuser ), :message => "You don't belong here"
# validates_exclusion_of :age, :in => 30..60, :message => "This site is only for under 30 and over 60"
# validates_exclusion_of :format, :in => %w( mov avi ), :message => "extension %{value} is not allowed"
# validates_exclusion_of :password, :in => lambda { |p| [p.username, p.first_name] },
# :message => "should not be the same as your username or first name"
# end
#
# Configuration options:
# * <tt>:in</tt> - An enumerable object of items that the value shouldn't be
# part of. This can be supplied as a proc or lambda which returns an enumerable.
# If the enumerable is a range the test is performed with <tt>Range#cover?</tt>
# (backported in Active Support for 1.8), otherwise with <tt>include?</tt>.
# * <tt>:within</tt> - A synonym(or alias) for <tt>:in</tt>
# * <tt>:message</tt> - Specifies a custom error message (default is: "is reserved").
# * <tt>:allow_nil</tt> - If set to true, skips this validation if the attribute
# is +nil+ (default is +false+).
# * <tt>:allow_blank</tt> - If set to true, skips this validation if the
# attribute is blank (default is +false+).
# * <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_exclusion_of(*attr_names)
validates_with ExclusionValidator, _merge_attributes(attr_names)
end
end
end
end
