$ git clone -n https://src.fedoraproject.org/rpms/ghc-shelly.git /var/lib/mock/f39-build-1507723-35294/root/chroot_tmpdir/scmroot/ghc-shelly
Cloning into '/var/lib/mock/f39-build-1507723-35294/root/chroot_tmpdir/scmroot/ghc-shelly'...
$ git fetch origin f19b42dd91258ce1c351188d1d806473d93ee9ae:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-shelly
 * [new ref]         f19b42dd91258ce1c351188d1d806473d93ee9ae -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f19b42d update to 1.12.1