See https://bugzilla.rpmfusion.org/show_bug.cgi?id=3068.

When building http://download1.rpmfusion.org/free/fedora/releases/20/Everything/source/SRPMS/get_iplayer-2.80-7.fc20.src.rpm on Fedora 20, the resulting package has no Perl dependencies.  The dependencies are determined correctly on Fedora 19:

> mock -r fedora-20-i386 --rebuild /var/tmp/downloads/get_iplayer-2.80-7.fc20.src.rpm >& /dev/null && rpm -q --requires -p /var/lib/mock/fedora-20-i386/result/get_iplayer-2.80-7.fc20.noarch.rpm
rtmpdump
ffmpeg
id3v2
lame
mplayer
vlc
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
rpmlib(CompressedFileNames) <= 3.0.4-1
rpmlib(PayloadIsXz) <= 5.2-1

> mock -r fedora-19-i386 --rebuild /var/tmp/downloads/get_iplayer-2.80-7.fc20.src.rpm > & /dev/null && rpm -q --requires -p /var/lib/mock/fedora-19-i386/result/get_iplayer-2.80-7.fc19.noarch.rpm
rtmpdump
ffmpeg
id3v2
lame
mplayer
vlc
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
rpmlib(CompressedFileNames) <= 3.0.4-1
perl(base)
perl(Cwd)
perl(Encode)
perl(Env)
perl(Fcntl)
perl(File::Basename)
perl(File::Copy)
perl(File::Path)
perl(File::Spec)
perl(File::stat)
perl(Getopt::Long)
perl(HTML::Entities)
perl(HTTP::Cookies)
perl(HTTP::Headers)
perl(IO::Seekable)
perl(IO::Socket)
perl(LWP::ConnCache)
perl(LWP::UserAgent)
perl(POSIX)
perl(strict)
perl(Time::Local)
perl(URI)
/usr/bin/perl
rpmlib(PayloadIsXz) <= 5.2-1

This appears to be because rpmdeps ignores Perl modules if their filename does not end .pm, and file(1) on Fedora 20 incorrectly identifies the script as a Perl module, not a Perl script.