I think the problem with TDD is essentially the same problem as with any other development methodology, that of overemphasis of one aspect of the development process with respect to other aspects. When the tests become more important than the code being tested, you have a problem.

However, this problem is not a fundemental problem with the methodology, it is a problem with either the implementation or the day to day execution of it. Or both.

Just as an overzealous adherance to OO doctrine can lead to the disguising of an inherently global entity behind a design pattern that trades a the simple global for a complex one with the consequence of greater complexity and no real benefits. So, an overzealous adherence to TDD can lead to the situation where the test suit takes on a greater importance than the code under test.

One of the signs of this overzealous application of a methodology is when the important part--ie. the code--starts to be designed around or altered to accomodate the methodology. Another is when the final purpose of the code becomes subordinated by the goals of the methodology. When "100% tests passed" or "100% code coverage acheieved" goals take a higher priority than "the code functions within specification", the real goal has been lost and the problem has arisen.

It is also important to realise that fixing the problem means adjusting the methodology or it's implementation, not throwing it away in favour of some new "magic bullet".

If there is one lesson that history can teach us with respect to code development, it's that being taken in by the promises of the latest, greatest, buzzword-complient paradigm to the exclusion of previous hard-won experience and common sense, invites history to bite us in the arse as we re-learn the forgotton lessons.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

In reply to Re: A danger of test driven development. by BrowserUk
in thread A danger of test driven development. by Perl Mouse

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