$ git clone -n https://src.fedoraproject.org/rpms/Mayavi.git /var/lib/mock/f40-build-2716305-72605/root/chroot_tmpdir/scmroot/Mayavi
Cloning into '/var/lib/mock/f40-build-2716305-72605/root/chroot_tmpdir/scmroot/Mayavi'...
$ git fetch origin a927b89923e307c418133edc8dd0f31fc5bdd3c7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/Mayavi
 * [new ref]         a927b89923e307c418133edc8dd0f31fc5bdd3c7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a927b89 Update to latest git snapshot (FTBFS bz#2260963)