Tests are simply one way of adding redundancy to your code with the idea that reification of a concept is less likely to be incorrect if it is implemented in two different ways. There are other ways to add this redundancy, for example assertions (assuming you have a tool that does model-checking) or static type system annotations.

Whenever you add redundancy, you also add inertia -- resistance to change -- because now each change that you make must be made in (at least) two places: ideally two different ways in those two places.

use-case testing is almost always necessary because it is unlikely that any specification can fully capture the nuances of the requirements. Unit testing is somewhat more fungible.

--Dave
Opinions my own; statements of fact may be in error.

In reply to Re: Testing 1...2...3... by dpuu
in thread Testing 1...2...3... by raybies

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.