$ git clone -n https://src.fedoraproject.org/rpms/antlr4-project.git /var/lib/mock/f42-build-866039-173661/root/chroot_tmpdir/scmroot/antlr4-project
Cloning into '/var/lib/mock/f42-build-866039-173661/root/chroot_tmpdir/scmroot/antlr4-project'...
$ git fetch origin 80e08c0e6a24af8360a29dca237b10b7e64565f1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/antlr4-project
 * [new ref]         80e08c0e6a24af8360a29dca237b10b7e64565f1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 80e08c0 Add java-headless dependency to the antlr4 package