Forum: RSpec Module instance variable remains set

Hi,

I have an issue with rSpec when spec'ing a module. The module in
question looks like this:

module Sheep
  def self.sound
    @sound ||= produce_sound()
  end
end

This module is used all around the application (and corresponding
specs) and somehow values of @sound leak between each spec. The only
way I found to fix it is to manually set the instance variable (with
instance_variable_set) to nil. Obviously this is Bad. Is there a way
to do this globally or better yet to prevent this?

With kind regards,
Harm

Addendum: I'm using rspec 1.3.0, rspec-rails 1.3.2 and ruby 1.9.1p129

On 22 Feb 2010, at 19:45, Harm wrote:

>
> This module is used all around the application (and corresponding
> specs) and somehow values of @sound leak between each spec. The only
> way I found to fix it is to manually set the instance variable (with
> instance_variable_set) to nil. Obviously this is Bad. Is there a way
> to do this globally or better yet to prevent this?

By using class methods like this, you're always going to have leaky
state. Here's one way to work around this:

class Sheep
   class << self
     def reset!
       @instance = nil
     end

     private

     def method_missing(message, *args)
       instance.send(message, *args)
     end

     def instance
       @instance ||= new
     end
   end

   def sound
     @sound ||= produce_sound()
   end
end

Now you can call Sheep.reset! between examples, and you'll get a brand
new Sheep instance each time. The old Sheep.sound API will still work
fine.

The added bonus is you can now spec the Sheep class properly too,
without having to worry about leaky state there either.

>
> With kind regards,
> Harm
>
> _______________________________________________
> rspec-users mailing list
> rspec-users@rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users

cheers,
Matt

http://mattwynne.net
+447974 430184