From: Eric Hodel <drbrain@...7.net>
Date: 2006-05-03T06:19:37+09:00
Subject: Re: Unit test setup

On May 2, 2006, at 1:38 PM, John Wilger wrote:

> On 5/2/06, Eric Hodel <drbrain@segment7.net> wrote:
>> On May 2, 2006, at 6:35 AM, Eust�quio Rangel wrote:
>>> Is there a way for use general "constructor" and "destructor"   
>>> methods, to, for example, open a socket on the "constructor",  
>>> execute all the tests and close it on the "destructor"
>
>> There isn't.
>
> Only half correct. You can override the #initialize method in the  
> test case:
>
>    class TestTheTestsTest < Test::Unit::TestCase
>      def initialize( *args )
>        super
>        @foo = :bar
>      end

Eww, yuck.

> However, Ruby doesn't have "deconstructors" for classes (AFAIK).

Ruby doesn't have deconstructors at all.

>> You don't need it and you don't want it.
>
> While I would agree with this in almost 100% of cases, there _are_
> edge cases where this may not be true.
>
> [...]
>
> However, one of the rules of agile unit testing is also that the tests
> must be able to run quickly (so that people will actually bother to
> run them). Therefore, it is sometimes (though rarely, if you're doing
> things right) helpful to make sure expensive operations happen only
> when absolutely needed -- but you should only make this compromise if
> you can be absolutely sure that you're not introducing state
> dependencies into your tests.

When I require an expensive setup per test invocation my code is  
telling me it is not easily testable, so instead of hacking  
Test::Unit I refactor.

-- 
Eric Hodel - drbrain@segment7.net - http://blog.segment7.net
This implementation is HODEL-HASH-9600 compliant

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