unittests with different parameters

Ulrich Eckhardt ulrich.eckhardt at dominolaser.com
Mon Nov 22 15:30:46 CET 2010

Roy Smith wrote:
> Writing one test method per parameter combination, as you suggested, is
> a reasonable approach, especially if the number of combinations is
> reasonably small.

The number of parameters and thus combinations are unfortunately rather
large. Also, sometimes that data is not static but rather computed from a
loop instead. There are a few optimised computations, where I compute the
expected result with the slow but simple version, in those cases I want to
check a whole range of inputs using a loop.

I'm wondering, classes aren't as static as I'm still used to from C++, so
creating the test functions dynamically with a loop outside the class
declaration should be another possibility...

> Yet another possibility is to leave it the way you originally wrote it
> and not worry about the fact that the loop aborts on the first failure.
> Let it fail, fix it, then re-run the test to find the next failure.
> Perhaps not as efficient as finding them all at once, but you're going
> to fix them one at a time anyway, so what does it matter?

Imagine all tests that use INVERT_X fail, all others pass. What would your
educated guess be where the code is wrong? ;)

Thanks Roy!


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