Re: Use of "Action stamps" in commit messages

[Eli Zaretskii]

> From: Radon Rosborough <address@hidden>
> Date: Fri, 13 Jul 2018 11:07:26 -0600
> Cc: Andy Moreton <address@hidden>, emacs-devel <address@hidden>
> 
> > They will stop being useful if we ever change our VCS.
> 
> Maybe I'm missing something, but -- if we change to a different VCS,
> we are going to have to rewrite all the history anyway. Why would it
> be difficult to have a filter that goes through and replaces all the
> Git commit IDs with the corresponding ones for the new VCS?

How do you know that a particular string of hex digits is a Git SHA1
of a commit?  A human might be able to make that decision, but a
program that converts the entire repository will be unable to do that
reliably.  The low reliability of such conversions in the pats was
what caused us to adopt the "action stamp" notation.

> Sure, it'd be annoying and possibly fairly difficult, but changing to
> a different VCS is a thing that -- even if it does happen, which I
> doubt -- will happen extremely rarely.

It doesn't matter how rarely this happens, because when it does, you
want the entire project history to still be readable and useful.