$ svn log -c r80 test/ | tail -n 2 | head -n 1

$

$ dir=test/
$ svn log "${dir}" | grep -oE '^r[0-9]+'
        | while read -r rev; do
                svn log --diff -c ${rev} "${dir}" > "${rev}-${dir//*/}.patch";
        done

$ patch -p 0 < r80-test.patch