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in reply to Re^2: Test/ Code Ratio
in thread Test/ Code Ratio

Two comments on this:

  1. 99.98% isn't feel good if your goal is 100%. When I'm evaluating test results, I don't care about percentage -- I want to see zero test failures. Feeling good at 99.98% is an attitude problem, not a Test::Harness problem.
  2. I've personally found that test-driven development works for me and that Test::Harness, et al., make that quick and easy. The power of writing tests first is in having to be absolutely clear what output I expect before I write my code. If that leads to tons of little tests, so be it. The point isn't that I've written lots of tests, it's that I've clearly specified the requirements of my module/application in a verifiable way.

    If the tests don't flag some broken behavior despite having tons of little tests, that's a failure on my part to write a good specification, not a failure of Test::Harness. E.g., if I don't specify what the application should do when input is faulty, then any behavior is acceptable because I haven't constrained it. Defensive coding ("open or die") is just a coders response to make the best of a poorly specified situation.

Like most tools, Test::* modules are only constructive in the hands of a skilled user. To the OP's point, are lots of lines of test code relative to lines of application code a sign of redundancy or inelegance or a well-thought-out and comprehensive specification of behavior? The answer depends entirely on the specific application and code (and it might be a combination of those, as well).

-xdg

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