$ git clone -n https://src.fedoraproject.org/rpms/rust-alga_derive.git /var/lib/mock/f40-build-1971226-25220/root/chroot_tmpdir/scmroot/rust-alga_derive
Cloning into '/var/lib/mock/f40-build-1971226-25220/root/chroot_tmpdir/scmroot/rust-alga_derive'...
$ git fetch origin fe922f69f52550d2047c073110e765ac4ab5a77a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-alga_derive
 * [new ref]         fe922f69f52550d2047c073110e765ac4ab5a77a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fe922f6 Include patch to fix doctests with Rust 1.80+