I posted this over at use.perl. I figured I'd stuff it here some someone else may learn from my pain.

I'm such and idiot. I can't believe I never noticed this before. It's quite a dangerous oversight too since it meant tests didn't register a pass or a fail; no output at all which threw off the test counts. Don't let this happen to you.

---some.t--- use Test::More tests => 2; use Error ':try'; use_ok('MyModule'); try { MyModule->foo('badparam'); } catch with MyModule::Exception { pass; } otherwise { fail; }

Of course, if the module throws the exception, we pass. If it throws another exception (or die), we fail. But, if the module unexpectedly succeeds, we neither fail nor pass. That's not so bad right? THe count mismatch would cause the test to fail right? Sure, but picture this:

---some.t--- use Test::More tests => 2; use Error ':try'; use_ok('MyModule'); try { MyModule->foo('badparam'); } catch with MyModule::Exception { pass; } otherwise { fail; } ok('added this test later in this huge test file');

In this scenerio, you've added a test but forgot to update the test plan count. Now you've declared 2 tests and passed 2 tests. No failures and you never know a completely failing test...didn't. This is ever more true if you're using no_plan. Probably another reason not to ever do that. :-)

Ths answer of course is to put a fail in the try block. Not something that seams obvious upon first thought.

---some.t--- use Test::More tests => 2; use Error ':try'; use_ok('MyModule'); try { MyModule->foo('badparam'); fail; } catch with MyModule::Exception { pass; } otherwise { fail; }

Boy do I have a lot of test files to double check. That was a painful lesson.


In reply to How not to test exceptions by jk2addict

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.