$ git clone -n https://src.fedoraproject.org/rpms/rubygem-pg.git /var/lib/mock/f40-build-733960-105598/root/chroot_tmpdir/scmroot/rubygem-pg
Cloning into '/var/lib/mock/f40-build-733960-105598/root/chroot_tmpdir/scmroot/rubygem-pg'...
$ git reset --hard 134cc6effec66b412504f921a93ae2c9611c9696
HEAD is now at 134cc6e Upgrade to pg 1.5.4.