Re: Is Aunit helpful?

[Stephen Leake <stephen_leake@stephe-leake.org>]

Midoan <midoan.ses@gmail.com> writes:

> On Aug 14, 6:57 am, Stephen Leake <stephen_le...@stephe-leake.org>
> wrote:
>> "Yannick Duchêne (Hibou57)" <yannick_duch...@yahoo.fr> writes:
>>
>> > About AUnit: just seen about what it is, how it is set up and how it
>> > works. Seems a question is still pending : “how to be sure the test
>> > cover  all relevant case ?”. I do not see a way to be sure testing
>> > cover all  cases.
>>
>> Correct, AUnit does not do that. gcov does, although I have not used it
>> very much. It can be difficult to use the output of gcov.
>>
>> > That is the main limitation of this kind of approach.
>>
>> What alternative approaches provide coverage information?
>>
>
> FYI, note that with Mika (http://www.midoan.com/), the automatic test
> data  generator for Ada, it is possible to take in your existing test
> cases, check the coverage achieved, and automatically generate missing
> test inputs and expected test result 

How can a tool possibly generate expected results? If it reads the code,
it can only generate the results that the code _will_ produce. But
that's the opposite of a test; the expected results are what the code
_should_ produce, based on some other spec (not the Ada spec). A testing
process _must_ assume the code is wrong.

If the spec is machine readable, then the tool has a chance. But I see
no mention of machine readable specs on the midoan site.

Hmm. If the Ada spec includes pre/postconditions (Ada 2012), then some
meaningful tests can be generated, but the compiler will already do
that.

> (which can be validated to form new test cases automatically).

validated by what? If that means "reviewed by a human", that might be
ok. But there would be a very strong temptation to say "the tool must be
right". 

> This can be done to achieve branch, decision or MC/DC coverage as
> desired.

Generating a scaffold that gives coverage could be useful, but it must
be completed manually, to ensure correct results.

-- 
-- Stephe