From: Robert Klemme <bob.news@...>
Date: 2005-03-15T23:31:18+09:00
Subject: Re: Mocking new and other class methods


"jeem" <jeem.hughes@gmail.com> schrieb im Newsbeitrag
news:1110841586.340637.7980@g14g2000cwa.googlegroups.com...
> Sorry, I'll try to clarify.
>
> When I type this:
>
> mn=MockNew.new(A)
> mn.handle { block }
>
> I'm saying, "Next time someone calls A.new(args), execute this block
> instead."  This lets me test code like this:
>
> def methodToTest
>   etc
>   a = A.new('bob')
>   a.etc
> end
>
> Usually I want to find some other way to test code like this, but if
> A.new or a.etc hits the file system or network, etc., I really want to
> be able to sub in a mock.  Often we deal with this by passing in the
> object, thus isolating the object creation code.  This still leaves the
> creation code untested, and a good place for bugs to hide.

Well, my example is easily modified to do that also, just add

def handle(&b)
  @handlers << b if b
end

My main point was, that you don't have to mess with the original class
instance.  You can just use any object as stand in that implements #new.

Kind regards

    robert