1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

  # Require the contact details unless the listing uses a central contact
  # This works
!!  validates_presence_of :contact_name, :contact_phone, :contact_email, :if => :do_not_use_central_contact?
  
  # This doesn't
!!  validates_presence_of :contact_name, :contact_phone, :contact_email, :unless => :use_central_contact?

  # Check if the listing uses a central contact
  def use_central_contact?
    return false unless listing
    listing.use_central_contact?
  end
  
  # Check if the listing does not use a central contact. Just a handy method.
  # This is the same as !use_central_contact? but we can't use that in the model validations
  def do_not_use_central_contact?
    !use_central_contact?
  end