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How do I code lots of simple tests

Ian Bicking ianb at colorstudy.com
Wed Oct 22 15:20:13 EDT 2003 
On Tuesday, October 21, 2003, at 11:48 PM, Jeremy Fincher wrote:
> Ian Bicking <ianb at colorstudy.com> wrote in message 
> news:<mailman.319.1066774834.2192.python-list at python.org>...
>> (And it uses double-underscore variables, like it's just
>> *trying* to piss me off!  Double-underscore variables are so arrogant
>> and patronizing.
>
> Don't look at it like that.  Double-underscore variables are for
> averting namespace problems, not for protection.  Unittest uses them
> not to protect itself, but to keep from stomping all over your
> namespace when you subclass it.  In that way, it's very much built
> with subclassing in mind.

I never have problems with namespaces like that.  If you really do have 
significant likelihood of a namespace clash then you shouldn't be using 
inheritance -- some of those instance variables should be shifted into 
a separate object.

I generally assume that a subclass is made with the superclass in mind, 
and that subclasses will be respectful of the requirements of the 
superclass.  If I'm not sure I trust the subclassing programmer, then 
I'll add lots of asserts.  The asserts cover the *actual* requirements. 
  Double-underscore says "I won't even tell you the requirements, 
because I don't believe you can be trusted with them.  Instead I'll 
hide it all from you."  You can still unmangle the names -- which I 
frequently do -- but it's annoying.

This is open source -- sure, things may change in some later version, 
and if I go playing around with undocumented interfaces then I won't be 
surprised if some future version breaks my code.  I'm okay with that, 
and it should be my choice to make fragile code if I want.

--
Ian Bicking | ianb at colorstudy.com | http://blog.ianbicking.org
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