lib/active_model/validations/absence.rb
# frozen_string_literal: true module ActiveModel module Validations # == \Active \Model Absence Validator class AbsenceValidator < EachValidator # :nodoc: def validate_each(record, attr_name, value) record.errors.add(attr_name, :present, **options) if value.present? end end module HelperMethods # Validates that the specified attributes are blank (as defined by # Object#present?). Happens by default on save. # # class Person < ActiveRecord::Base # validates_absence_of :first_name # end # # The first_name attribute must be in the object and it must be blank. # # Configuration options: # * <tt>:message</tt> - A custom error message (default is: "must be blank"). # # There is also a list of default options supported by every validator: # +:if+, +:unless+, +:on+, +:allow_nil+, +:allow_blank+, and +:strict+. # See ActiveModel::Validations::ClassMethods#validates for more information. def validates_absence_of(*attr_names) validates_with AbsenceValidator, _merge_attributes(attr_names) end end end end