rails/activemodel/lib/active_model/validations/presence.rb
2016-08-06 20:20:22 +02:00

39 lines
1.4 KiB
Ruby

module ActiveModel
module Validations
class PresenceValidator < EachValidator # :nodoc:
def validate_each(record, attr_name, value)
record.errors.add(attr_name, :blank, options) if value.blank?
end
end
module HelperMethods
# Validates that the specified attributes are not blank (as defined by
# Object#blank?). Happens by default on save.
#
# 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").
#
# There is also a list of default options supported by every validator:
# +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +: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