module ActiveRecord
module Validations
class PresenceValidator < ActiveModel::Validations::PresenceValidator # :nodoc:
def validate_each(record, attribute, association_or_value)
return unless should_validate?(record)
if record.class._reflect_on_association(attribute)
association_or_value = Array.wrap(association_or_value).reject(&:marked_for_destruction?)
end
super
end
end
module ClassMethods
# Validates that the specified attributes are not blank (as defined by
# Object#blank?), and, if the attribute is an association, that the
# associated object is not marked for destruction. Happens by default
# on save.
#
# class Person < ActiveRecord::Base
# has_one :face
# validates_presence_of :face
# end
#
# The face attribute must be in the object and it cannot be blank or marked
# for destruction.
#
# 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>.
#
# This validator defers to the ActiveModel validation for presence, adding the
# check to see that an associated object is not marked for destruction. This
# prevents the parent object from validating successfully and saving, which then
# deletes the associated object, thus putting the parent object into an invalid
# state.
#
# NOTE: This validation will not fail while using it with an association
# if the latter was assigned but not valid. If you want to ensure that
# it is both present and valid, you also need to use +validates_associated+.
#
# Configuration options:
# * <tt>:message</tt> - A custom error message (default is: "can't be blank").
# * <tt>:on</tt> - Specifies the contexts where this validation is active.
# Runs in all validation contexts by default (nil). You can pass a symbol
# or an array of symbols. (e.g. <tt>on: :create</tt> or
# <tt>on: :custom_validation_context</tt> or
# <tt>on: [:create, :custom_validation_context]</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
