[cmake-developers] Review Request for ExternalProjects: Only update certain git submodules

[David Cole]

This looks like a reasonable patch to me (just by eye, have not tried 
it personally). *Although* it would be even better if there were an 
additional case added in the ExternalProject test that handles passing 
in (1) an empty git submodule list, and (2) a valid list. Although, 
unless you add code to the setup of the test git repo for that test, it 
won't have any submodules in it. And we don't want to introduce any 
network dependencies to the test suite, so no referencing a real live 
git repo on the internet.

I'd like to see a follow up patch to this one that adds *some* testing, 
too, even if just of the empty list smoke test variety...

Does anybody listening here have a project with some git submodules, 
and some time to give this a test drive? If so, please do, and let us 
know the results. If they're positive, we could take the follow up to 
this patch and get it into CMake 'next'.


Thanks,
David C.