$ git clone -n https://src.fedoraproject.org/rpms/tcpdump.git /var/lib/mock/f29-build-1614-562/root/thebuilddir/tmp/scmroot/tcpdump
Cloning into '/var/lib/mock/f29-build-1614-562/root/thebuilddir/tmp/scmroot/tcpdump'...
$ git reset --hard 0a59dcfef4b392c3c101eb544b9c6f48a878c2f6
HEAD is now at 0a59dcf Add gcc to BuildRequires