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[Help] What is the best way to compare two forms for a sunit test?

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Jerome Peace

[Help] What is the best way to compare two forms for a sunit test?

I have some code for which I have created graphical
tests .

These tests will produce a picture that looks right
when the code is working.

Now I want to (as lazily as possible) create unit
tests to prove the code and get it past the release
team watch dogs.

For each sample in the test I can get a form. Reduce
it to the smallest meaningful depth. So the next step
is to encode it into something that can be returned by
a method and compared with (what is hopefully) the
same form generated by the test.

What is the best way to do this?

I can anticipate this testing method coming up again.

It would be nice to automate the "encode it into a
method" part. At least to the point where I had
something that wrote the method (or most of it) into a
code holder or some text buffer I could copy.

For testing purposes it would be sufficient to test
the compressed forms (or even suitable hashes maybe).
Just as long as I could have confidence that the two
pictures matched.

I figure someone out there has probably tackled this
problem before so I am hoping to avoid reinventing the
wheel.

Yours in curiosity and service, --Jerome Peace

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Andreas.Raab

Re: [Help] What is the best way to compare two forms for a sunit test?

Combination rule 32 (RGB diff) which counts the number of differing
pixels in two forms is your friend. For example:

(BitBlt toForm: Display)
sourceForm: Display;
combinationRule: 32;
copyBits.

will answer zero (no difference, since it's the same form). One caveat
though: This only works for >=16bpp; if you need less than you may have
to look at rule 22 which is a bit tricky since it does not clip properly
(but it may still be good enough for your purposes).

Cheers,
- Andreas

Jerome Peace wrote:

> I have some code for which I have created graphical
> tests .
>
> These tests will produce a picture that looks right
> when the code is working.
>
> Now I want to (as lazily as possible) create unit
> tests to prove the code and get it past the release
> team watch dogs.
>
> For each sample in the test I can get a form. Reduce
> it to the smallest meaningful depth. So the next step
> is to encode it into something that can be returned by
> a method and compared with (what is hopefully) the
> same form generated by the test.
>
> What is the best way to do this?
>
> I can anticipate this testing method coming up again.
>
> It would be nice to automate the "encode it into a
> method" part. At least to the point where I had
> something that wrote the method (or most of it) into a
> code holder or some text buffer I could copy.
>
> For testing purposes it would be sufficient to test
> the compressed forms (or even suitable hashes maybe).
> Just as long as I could have confidence that the two
> pictures matched.
>
> I figure someone out there has probably tackled this
> problem before so I am hoping to avoid reinventing the
> wheel.
>
> Yours in curiosity and service, --Jerome Peace
>
>
>
>
>
> ____________________________________________________________________________________
> Do you Yahoo!?
> Everyone is raving about the all-new Yahoo! Mail beta.
> http://new.mail.yahoo.com
>
>