Re: master cbef1e9 2/3: ; make change-history-commit

[Paul Eggert <eggert@cs.ucla.edu>]

Robin Templeton wrote:
> If only corrections to specific commits were stored,
> it would be possible to amend the log messages as viewed with git
> commands, perhaps using git object notes.

I originally proposed that -- it's the approach Coreutils takes -- but the 
Coreutils approach turns out to be too much of a pain to understand and use in 
the context of Emacs development.  Glenn did suggest object notes, but as I 
understand it Emacs VC doesn't support them.  So I went with the best 
easy-enough approach that I could think of, an approach based on Emacs's 
tradition of ChangeLog history files.  If we can think of something better, we 
should switch to it.

> Separating corrections could also completely eliminate ChangeLog merge
> conflicts.

I don't see how.  No matter how one versions corrections, merge conflicts can 
occur if concurrent developers generate different corrections for the same 
ChangeLog entry.  Perhaps Git wouldn't identify them as conflicts, but they'd 
still be conflicts.  Certainly object notes can have conflicts.

That being said, I expect the current scheme will greatly reduce merge conflicts 
in practice.  For example, I expect it would have avoided RMS's merge conflict 
that started that looooong recent thread.