[cmake-developers] How to fix FindSquish.cmake wrt. backward compatibility ?

[Alexander Neundorf]

On Sunday 04 November 2012, Alexander Neundorf wrote:
> Hi,
> 
> I finally want to commit my changes to FindSquish.cmake upstream.
> FindSquish.cmake as it comes with cmake does not work at all with squish
> version 4.x.
> The documentation of FindSquish.cmake says it is currently aimed at version
> 3. This is this bug: http://public.kitware.com/Bug/view.php?id=9734
> 
> There have been no (zero) commits to FindSquish.cmake after its initial
> commit, except of cleanup commits:
> http://cmake.org/gitweb?p=cmake.git;a=history;f=Modules/FindSquish.cmake;h=
> HEAD;hb=next
> 
> 
> I suspect that FindSquish.cmake as it comes with cmake does not work with
> squish 4.x because squish may have changed from 3.x to 4.x. But this is
> just guessing, I don't have squish 3.x available.
> 
> So, how should I proceed ?
> 
> 1) Add a FindSquish4.cmake, which works with squish 4, and leave
> FindSquish.cmake untouched ?
> 
> 2) Just make FindSquish.cmake work with squish 4.x, and ignore that this
> may break it for squish 3.x ? (...maybe this wouldn't be a real problem,
> as there is no bug report for FindSquish.cmake in the bug tracker (except
> the one I filed #9734). So maybe nobody is using it with squish 3.x ?
> 
> 3) Detect the version in FindSquish.cmake, and do different things if
> version 3 or version 4 are detected ? FindSquish.cmake provides a macro
> squish_add_test(). The syntax for using it has changed with my changes for
> squish 4. So, should FindSquish.cmake provide a macro squish_add_test()
> with one set of parameters if version 3 is found, and a function also
> named squish_add_test() with a different set of parameters if squish 4 is
> found ? This doesn't feel good to me, having a function with the same name
> but different arguments depending on the version which was found.
> Or should it provide squish_add_test_v4() is version 4 is found ?

I think I'll add a squish_add_test3() which will be a wrapper for the current 
squish_add_test(), and additionally a new squish_add_test4() which will work 
for version 4.

Does that sound ok ?

Alex