One of the users of my Debian packaging of sudo pointed out a while back that a change in sudoers syntax or semantics at one point caused him to lose root access to a system he was in the process of upgrading, and he thus requested that I add a check to my packaging to validate the content of sudoers and abort the upgrade if it appears incompatible with the new sudo version being installed.

I suspect there's a way to do this reliably with the existing sudo options and exit codes, but it's not immediately obvious what the best approach would be?  What we want, I think, is just a "go/no-go" indication of whether sudo is going to run or error out when it reads and parses sudoers.  

Thoughts?

Bdale