Re: Testing a class which utilizes randomness

Hi Nikola,

On Apr 4, 2014, at 6:53 PM, Nikola Novak <[email protected]> wrote:

> Thanks everyone for your replies. Like I said, I'm not testing the RNG (or RSG in this case), but rather the algorithm which deals with duplicates.
> I'll go with what David and John suggested, writing a class to generate unique random strings and injecting a random string generator.
> Interesting how a TDD approach resulted in code being organized properly. If I hadn't used it, I'd probably have written a method that used an embedded random string generator and would never have given the problem a second thought.


Sounds like a good start. I’ve not built this but my intuition is telling me that the design would like to have a PuttingAway object that holds strings, and a MakingStrings object that builds random strings, and some structure, perhaps a PuttingAwayUnique object but perhaps not.

If I’m right, there will be no need to create random strings for purposes of putting away uniquely: you can work with strings like “Hello”, “Goodbye”, and “Hello”. If I’m right, that will make the PuttingAway tests simpler. And that will be better.

So I recommend pushing in that direction, trying a few ways, and seeing what you come up with.

Regards,

Ron Jeffries
www.XProgramming.com
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