$ git clone -n https://src.fedoraproject.org/rpms/rust-arg_enum_proc_macro.git /var/lib/mock/f38-build-side-42-init-devel-1395190-31050/root/chroot_tmpdir/scmroot/rust-arg_enum_proc_macro
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1395190-31050/root/chroot_tmpdir/scmroot/rust-arg_enum_proc_macro'...
$ git fetch origin 8bed78a5fc93fbe4ea9e2db4e805f2529173f028:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-arg_enum_proc_macro
 * [new ref]         8bed78a5fc93fbe4ea9e2db4e805f2529173f028 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8bed78a Update to version 0.3.4; Fixes RHBZ#2238499