$ git clone -n https://src.fedoraproject.org/rpms/rust-glib-macros.git /var/lib/mock/f39-build-1493646-34539/root/chroot_tmpdir/scmroot/rust-glib-macros
Cloning into '/var/lib/mock/f39-build-1493646-34539/root/chroot_tmpdir/scmroot/rust-glib-macros'...
$ git fetch origin 4ca2a129c706d15a49afb5b18cd02d1b79b502f4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-glib-macros
 * [new ref]         4ca2a129c706d15a49afb5b18cd02d1b79b502f4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4ca2a12 Update to version 0.18.2; Fixes RHBZ#2239032