$ git clone -n https://src.fedoraproject.org/rpms/gst-devtools.git /var/lib/mock/f42-build-side-1-3502667-45978/root/chroot_tmpdir/scmroot/gst-devtools
Cloning into '/var/lib/mock/f42-build-side-1-3502667-45978/root/chroot_tmpdir/scmroot/gst-devtools'...
$ git fetch origin fb4c202ba5d3d6addb5b88cbf369c707f8cbdc6a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gst-devtools
 * [new ref]         fb4c202ba5d3d6addb5b88cbf369c707f8cbdc6a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fb4c202 Disable dots_viewer