Date validation breaks, maybe because of ActiveAdmin datepicker

[Koroeskohr]

Using Ruby 2.3.1, Rails 4.2.6, ActiveValidators 4.0.0

I have a PressRelease model that has a datetime field, released_at. When using ActiveAdmin's datepicker, my date validation (that looks like this : )

class PressRelease < ActiveRecord::Base
  validates :released_at, presence: true, date: { before: lambda { Time.now }, after: lambda { 50.years.ago } }
end

breaks and throws an ArgumentError : wrong number of arguments (given 1, expected 0).

I also use the URL validation, no problem with this one.

Full trace : trace.txt

[alyssais]

This error comes from your before: and after: lambdas. Using a lambda means that any the number of arguments you've specified is enforced with an exception. The date validator passes an argument to these when it calls them, which is what's causing your error.

To fix the error, change your lambdas to procs to ignore the argument silently.

[Koroeskohr]

The documentation in the README would then be the issue here :

class Article
  validates :slug,            :slug => true
  validates :expiration_date, :date => {
                                          :after => lambda { Time.now },
                                          :before => lambda { Time.now + 1.year }
                                        }
end