From: Kent Dahl <kentda+news@...>
Date: 2004-05-08T18:03:54+09:00
Subject: Re: test unit & singleton

Gennady wrote:
> That's why you want to avoid singletons as much as possible when it 
> comes to unit testing.
> 
> In cases I do need singletons, I usually end up with a regular class 
> that can be unit tested, and a separate singleton class that simply 
> delegates all calls to my actual class. Or something similar.

Suggestion for something similar, w/o the delegation overhead:

Move all functionality of the singleton class into a module. Include 
that module in two classes, one which also includes Singleton (for 
actual use) and one dummy class for testing. Put the code for the dummy 
class in the unit tests themselves, so the application code doesn't 
accidentally use it for anything.

require 'singleton'
module RealStuff
   # ...
end
class DummyClass
   include RealStuff
end
class RealClass
   include RealStuff
   include Singleton
end

-- 
(\[ Kent Dahl ]/)_    _~_    _____[ http://www.pvv.org/~kentda/ ]_____/~
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