Is there any way I can check for whitespace/tab (i.e. don't use tab, use spaces instead, and do have end of line space) in my git commits?
I have ~ 10 commits, I want to double check them before I push.
What Git mechanism should apply for this case?
The right way to "double check" is through a pre-commit hook to detect whitespace errors.
(You will find hook examples there)
Trying to do that just before a push is a bit late, even though git1.8.2 has now a pre-push hook.
You can still:
rebase -i HEAD~10
(replaying all your 10 commits), which will trigger that pre-commit hook.