ref: e74f1325f94ecec259f7292aad9be5605b755843 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