ref: e269212796f765b89065cf7c5d0d431d6b4546ba
dir: /sys/src/cmd/diff/test/merge5.expected/
lc: (2,1)::(2,4) rc: (4,7)::(4,7) 1 a b c lc: (5,5)::(8,8) rc: (4,7)::(4,7) 2 3 <<<<<<<<<< test/merge-t5.l 4 x 6 7 ========== original 4 5 6 7 ========== test/merge-t5.r w x y z >>>>>>>>>> 8 9 10