ref: 5e4b3a7490d301a7547a021bf1cf1e2d0f25de21 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