class Shoulda::Matchers::ActiveModel::ValidatePresenceOfMatcher

def failure_message
  message = super
  if should_add_footnote_about_belongs_to?
    message << "\n\n"
    message << Shoulda::Matchers.word_wrap(<<-MESSAGE.strip, indent: 2)
etting this error because #{reason_for_existing_presence_validation}.
resence validation doesn't use "can't be blank", the usual validation
 but "must exist" instead.
t said, did you know that the `belong_to` matcher can test this
on for you? Instead of using `validate_presence_of`, try
tions_for_belongs_to}
    MESSAGE
  end
  message
end