module ActiveModel
module Validations
class LengthValidator < EachValidator
MESSAGES = { :is => :wrong_length, :minimum => :too_short, :maximum => :too_long }.freeze
CHECKS = { :is => :==, :minimum => :>=, :maximum => :<= }.freeze
DEFAULT_TOKENIZER = lambda { |value| value.split(//) }
def initialize(options)
if range = (options.delete(:in) || options.delete(:within))
raise ArgumentError, ":in and :within must be a Range" unless range.is_a?(Range)
options[:minimum], options[:maximum] = range.begin, range.end
options[:maximum] -= 1 if range.exclude_end?
end
super(options.reverse_merge(:tokenizer => DEFAULT_TOKENIZER))
end
def check_validity!
keys = CHECKS.keys & options.keys
if keys.empty?
raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.'
end
keys.each do |key|
value = options[key]
unless value.is_a?(Integer) && value >= 0
raise ArgumentError, ":#{key} must be a nonnegative Integer"
end
end
end
def validate_each(record, attribute, value)
value = options[:tokenizer].call(value) if value.kind_of?(String)
CHECKS.each do |key, validity_check|
next unless check_value = options[key]
options[:message] ||= options[MESSAGES[key]] if options[MESSAGES[key]]
valid_value = if key == :maximum
value.nil? || value.size.send(validity_check, check_value)
else
value && value.size.send(validity_check, check_value)
end
next if valid_value
record.errors.add(attribute, MESSAGES[key], options.merge(:count => check_value))
end
end
end
module HelperMethods
# Validates that the specified attribute matches the length restrictions supplied. Only one option can be used at a time:
#
# class Person < ActiveRecord::Base
# validates_length_of :first_name, :maximum=>30
# validates_length_of :last_name, :maximum=>30, :message=>"less than 30 if you don't mind"
# validates_length_of :fax, :in => 7..32, :allow_nil => true
# validates_length_of :phone, :in => 7..32, :allow_blank => true
# validates_length_of :user_name, :within => 6..20, :too_long => "pick a shorter name", :too_short => "pick a longer name"
# validates_length_of :zip_code, :minimum => 5, :too_short => "please enter at least 5 characters"
# validates_length_of :smurf_leader, :is => 4, :message => "papa is spelled with 4 characters... don't play me."
# validates_length_of :essay, :minimum => 100, :too_short => "Your essay must be at least 100 words."), :tokenizer => lambda {|str| str.scan(/\w+/) }
# end
#
# Configuration options:
# * :minimum - The minimum size of the attribute.
# * :maximum - The maximum size of the attribute.
# * :is - The exact size of the attribute.
# * :within - A range specifying the minimum and maximum size of the attribute.
# * :in - A synonym(or alias) for :within.
# * :allow_nil - Attribute may be +nil+; skip validation.
# * :allow_blank - Attribute may be blank; skip validation.
# * :too_long - The error message if the attribute goes over the maximum (default is: "is too long (maximum is %{count} characters)").
# * :too_short - The error message if the attribute goes under the minimum (default is: "is too short (min is %{count} characters)").
# * :wrong_length - The error message if using the :is method and the attribute is the wrong size (default is: "is the wrong length (should be %{count} characters)").
# * :message - The error message to use for a :minimum, :maximum, or :is violation. An alias of the appropriate too_long/too_short/wrong_length message.
# * :on - Specifies when this validation is active (default is :save, other options :create, :update).
# * :if - Specifies a method, proc or string to call to determine if the validation should
# occur (e.g. :if => :allow_validation, or :if => Proc.new { |user| user.signup_step > 2 }). The
# method, proc or string should return or evaluate to a true or false value.
# * :unless - Specifies a method, proc or string to call to determine if the validation should
# not occur (e.g. :unless => :skip_validation, or :unless => Proc.new { |user| user.signup_step <= 2 }). The
# method, proc or string should return or evaluate to a true or false value.
# * :tokenizer - Specifies how to split up the attribute string. (e.g. :tokenizer => lambda {|str| str.scan(/\w+/)} to
# count words as in above example.)
# Defaults to lambda{ |value| value.split(//) } which counts individual characters.
def validates_length_of(*attr_names)
validates_with LengthValidator, _merge_attributes(attr_names)
end
alias_method :validates_size_of, :validates_length_of
end
end
end