ref: f9fd6981241f28f056efe9be8db4dfc39266bee4 dir: /sys/src/cmd/diff/test/merge-t4.expected/
1 2 3 <<<<<<<<<< merge-t4.l 4 x 6 7 ========== original 4 5 6 7 ========== merge-t4.r w x y z >>>>>>>>>> 8 9 10