$ git clone -n https://src.fedoraproject.org/rpms/ghc-SHA.git /var/lib/mock/f31-build-53941-27924/root/thebuilddir/tmp/scmroot/ghc-SHA
Cloning into '/var/lib/mock/f31-build-53941-27924/root/thebuilddir/tmp/scmroot/ghc-SHA'...
$ git reset --hard b4348ab5395202f972e3045de4268b9fbd0be907
HEAD is now at b4348ab refresh to cabal-rpm-0.13