There are two utilities (possibly plugins) in the evolution package that bring in an entire perl requirement. Those two utils are:
I would be nice to be able to split them out to a separate evolution-perl package so that devices like netbooks (and the possible Fedora spins) don't necessarily need to pull in all of perl to have the evolution PIM as they often only have 2 gig of base flash (eg eeePC Surf 2G)
Evolution doesn't explicitly require Perl. Those two utilities are considered supplemental, and are not required for the normal operation of Evolution. So Perl would be a "suggested" package in Debian lingo.
That said, I see that Evolution /is/ dragging in Perl by some other requirement, but I'm not sure which. There's spamassassin, but that's already split into a separate package. There's autoconf and automake, but those are only build requirements. I don't see any other likely candidates.
Is there a good way to search for this or display an RPM dependency tree?
My understanding of RPM (and it could well be wrong) is that if a file in an RPM is a perl file it will pull in perl by default. Hence by just having these files in the package the depsolve routine will pull in perl as a result. I've seen other packages in the past either remove the offending files to remove the dependency or move them to a sub package to move the dep down a level. The other way of bringing in a perl dep is in scripting in the actual spec itself.
Example of moving it to a sub package is ntp
Example of it in the spec file is docbook-dtds
I use 'rpm -qR package' to see what a specific package depends on.
There's also other options in this mailing list post
Fixed in evolution-2.24.0-2.fc10.
$ rpm -q --requires evolution | grep perl
$ rpm -q --requires evolution-perl | grep perl