Validates with :if

Question

I'm trying to create a condition in which the attribute 'one' is zero and the attribute 'two' is one, then a model is not valid. But when I make:

Model.create(:one => 1, :two => 0).valid?

The unit test returns true! Why?

validates :one, :two, :presence => true, :if => :if condition_testing?

def condition_testing?
    !(one == 0 && two == 1)
end

Answer 1

I think you have an error in your syntax:

validates :one, :two, :presence => true, :if => :condition_testing?

def condition_testing?
    !(one == 0 && two == 1)
end

There was one :if too many in there... And if I understand correctly you want to have it only validate in case one == 0 && two == 1? Then you condition_testing? is inverted (leave out the !())

If unsure you could try to use pry and insert a breakpoint into your condition_testing? method to see what's going on.

(Please note added ":" before condition testing)

Answer 2

You can validate it in one line:

validates :one, :two, :presence => true, :if => Proc.new { |a| !(a.one == 0 && a.two == 1) }