"You need to supply at least one validation" but Rails validation exists

Question

I have the following validation:

class Event < ActiveRecord::Base
  attr_accessible :starts, :ends

  validates :no_multi_day_events

  private
    def no_multi_day_events
      if (ends.day != starts.day)
        errors.add(:ends, "No multi-day events")
      end
    end
end

However, when I try to load a page with this text, I get an error: You need to supply at least one validation

How do I supply the validation?

Answer 1

You should be calling:

validate :no_multi_day_events

and not

validates :no_multi_day_events