From: Michal Kwiatkowski <constant.beta@...>
Date: 2006-12-24T12:25:05+09:00
Subject: Re: Reverting module changes

Mat Schaffer wrote:
> On 12/23/06, Michal Kwiatkowski <constant.beta@gmail.com> wrote:
> > I want to mock standard Kernel.system with my own method and then
> > revert back to the original version. I was able to do the former, but
> > not the latter. Currently I'm overwriting Kernel.system method
> > definition with:
> >
> > def system_should_return what
> >     Kernel.module_eval "def system(*args) #{what.inspect} end"
> > end
> >
> > I don't a have idea how going back to the original state can be done.
> > Thanks in advance for any help on this.
>
> Maybe there's something more elegant.  But I'd first alias the
> original method, redefine it, then when I was done, I'd redefine it
> again to just call the alias.

Thanks, aliasing was what I was looking for. Does code below look OK or
can be improved?

def system_should_return what
    Kernel.module_eval <<-EOV
      alias_method :orig_system, :system
      def system(*args)
        #{what.inspect}
      end
    EOV
end

def restore_system_behaviour
    Kernel.module_eval <<-EOV
      def system()
        orig_system
      end
    EOV
end

Cheers,
mk