ref: 40cb72e7f8cda9d21e1b7f738f6281e181c0de9e dir: /sys/src/cmd/diff/test/merge-t3.expected/
1 2 3 4 <<<<<<<<<< merge-t3.l y ========== original 5 ========== merge-t3.r x >>>>>>>>>> 6 7 8 9 10