Push timestamps

[Andreas Gustafsson <gson%gson.org@localhost>]

Hi all,

It has come to my attention that Mercurial does not keep track of when
changes appear in the public repository.  The commit timestamp only
indicates when a change was initially committed in the developer's
local repository, which could be months before it appears in -current
(or some other public branch), especially when rebasing is involved.
From the parental lineage of the commits, you may be able to determine
the order in which the commits appeared, but not the date and time
when they did so.

This means that the Mercurial repository does not contain all the
information needed to generate reports showing the evolution of
-current on a calendar timeline, such as those generated from CVS at
http://releng.netbsd.org/b5reports/i386/.  It also means you can't
answer questions such as "when was this bug fixed in -current?" with
a date and time based only on the information in the repository.

IMO, this is significant shortcoming which needs to be addressed
before the NetBSD repository can be switched to Mercurial.  What
do others think?

The Mozilla project has a Mercurial extension called "pushlog" which
looks like it could provide the missing information:

  https://mozilla-version-control-tools.readthedocs.io/en/latest/hgmo/pushlog.html

Suggestions for other possible solutions are welcome, provided
they don't involve parsing source-changes emails (Zawinski's Law
notwithstanding).
-- 
Andreas Gustafsson, gson%gson.org@localhost