From: Matt Armstrong <matt@...>
Date: 2003-02-07T12:01:41+09:00
Subject: Re: Return values from assertions

Gavin Sinclair <gsinclair@soyabean.com.au> writes:

> On Friday, February 7, 2003, 2:52:38 AM, Matt wrote:
>
>>> Matt Armstrong [mailto:matt@lickey.com] wrote:
>>
>> That hits the crux of my question -- the only practical difference
>> between a failure and an error is that the error can have a nice error
>> message?
>
> The conceptual difference is practical enough for me.
>
> Conceptual difference:
>
>   - failure: specifically tested condition that, well, failed
>   - error: unexpected, uncaught exception
>
> If you expect that certain code will throw an exception, you test for
> it and record a success or failure.  If you don't expect an exception,
> and you get one, then either your code or your test is seriously
> wrong, in a different kind of way to a failed assertion.
>
> Therefore, failures and errors highlight different problems in the
> code, and this is a practical difference.

Even more to the point, I don't see a point to RubyUnit's
assert_no_exception or Test::Unit's assert_nothing_raised.
Conceptually, you're saying "this code shouldn't raise an exception
that is not handled" but that is pretty much universally true.

-- 
matt