t / t4013 / diff.noellipses-diff-tree_-c_--abbrev_masteron commit help_unknown_ref(): check for refname ambiguity (2ed2e19)
   1$ git diff-tree -c --abbrev master
   259d314ad6f356dd08601a4cd5e530381da3e3c64
   3::100644 100644 100644 cead32e 7289e35 992913c MM       dir/sub
   4::100644 100644 100644 b414108 f4615da 10a8a9f MM       file0
   5$