ref: 15544a747b6ca50989aa0d14315c3c13d3dfc1bc dir: /sys/src/cmd/diff/test/merge-t5.expected/
1 a b c 2 3 <<<<<<<<<< merge-t5.l 4 x 6 7 ========== original 4 5 6 7 ========== merge-t5.r w x y z >>>>>>>>>> 8 9 10