t / t4013 / diff.log_-SF_masteron commit describe: fix off-by-one error in --abbrev=40 handling (f712226)
   1$ git log -SF master
   2commit 9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0
   3Author: A U Thor <author@example.com>
   4Date:   Mon Jun 26 00:02:00 2006 +0000
   5
   6    Third
   7
   8$