$ git clone -n https://src.fedoraproject.org/rpms/rust-syn2.git /var/lib/mock/f45-build-45300-822/root/chroot_tmpdir/scmroot/rust-syn2
Cloning into '/var/lib/mock/f45-build-45300-822/root/chroot_tmpdir/scmroot/rust-syn2'...
$ git fetch origin 27385a0811935cc0074ed641a4b11e4e2b9cdd73:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-syn2
 * [new ref]         27385a0811935cc0074ed641a4b11e4e2b9cdd73 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 27385a0 Initial import (syn v2 compat package)