Bools and explicitness [was Re: PyWart: The problem with "print"]

[Grant Edwards]

On 2013-06-06, Chris Angelico <rosuav at gmail.com> wrote:

> Would you say that doubling the testing period is a good thing or a
> bad thing?

It could be a neutral thing (ignoring the costs involved).

I once read read an article claiming that as you test (and fix) any
large, complex piece of software, you asymptotically approach a
certain fixed "minimum number of bugs" that's determined by the
system's overall architecture, design and implentation.  Once you get
sufficiently close to that minimum, additional testing doesn't reduce
the number/severity of bugs -- it just "moves them around" by creating
additional bugs at the same rate you are eliminating old ones.  When
you get to that point, the only way to significantly improve the
situation is to toss the whole thing out and start over with a better
system architecture and/or development model.

After having maintined a few largish pieces of software for well over
a decade, I'm fairly convinced that's true -- especially if you also
consider post-deployment maintenance (since at that point you're
usually also trying to add features at the same time you're fixing
bugs).

-- 
Grant Edwards               grant.b.edwards        Yow! I just went below the
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