class ActiveModel::Validations::AcceptanceValidator

def acceptable_option?(value)
  Array(options[:accept]).include?(value)
end

def initialize(options)
  super({ allow_nil: true, accept: ["1", true] }.merge!(options))
  setup!(options[:class])
end

def setup!(klass)
  define_attributes = LazilyDefineAttributes.new(attributes)
  klass.include(define_attributes) unless klass.included_modules.include?(define_attributes)
end

def validate_each(record, attribute, value)
  unless acceptable_option?(value)
    record.errors.add(attribute, :accepted, **options.except(:accept, :allow_nil))
  end
end