This wish was found in the Debian Bug Tracker, submitted by 'luca', who I'm
adding to the 'nosy' list:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=462330

###

The Debian Common Lisp Team [2] would like to receive a mail every time
a new patch (or a patch bundle) is applied to one of its darcs
repositories ([3], point 3).

Searching on the darcs BTS gave only bug #304 [4], which is not exactly
the same issue I'm reporting.

Searching on the net was far more useful, since I found a patch by
Olivier Thauvin [5] which should allow such a feature in an easy way.
However, I could not find any "official" comment about Olivier's patch,
which seems to not have been applied in the stable nor unstable darcs
repositories.

What's available ATM is a shell script by Marco Baringer [6] (included
for archive purpose), which is already used for the BESE project [7].
While I ignore the original ideas behind this script, what's funny is
that its aim is exactly the same as Olivier Thauvin's patch [5].

Thx, bye,
Gismo / Luca

Footnotes: 
[1] http://darcs.debian.org
[2] http://pkg-common-lisp.alioth.debian.org
[3]
http://lists.alioth.debian.org/pipermail/pkg-common-lisp-devel/2008-January/000000.html
[4] http://bugs.darcs.net/issue304
[5] http://thread.gmane.org/gmane.comp.version-control.darcs.devel/4049
[6] http://alioth.debian.org/~gismo/darcs-email-changelog.sh
[7] http://common-lisp.net/project/bese/

I've just implemented this.  Most darcs commands now define DARCS_PATCHES
and/or DARCS_FILES, defining the patches and files affected, respectively.
There's minimal documentation added to the manual, but you should be able
to simply define in your _darcs/prefs/defaults something like

apply run-posthook
apply posthook echo $DARCS_PATCHES | mail -s 'Patch applied' user@host.com
-- 
David Roundy
Department of Physics
Oregon State University

Hi there!

Please keep the Debian BTS cc:ed, thanks.

On Mon, 04 Feb 2008 17:15:19 +0100, David Roundy wrote:
> I've just implemented this.  Most darcs commands now define
> DARCS_PATCHES and/or DARCS_FILES, defining the patches and files
> affected, respectively.

David, thank you for having worked on that.  However...

> There's minimal documentation added to the manual, but you should be
> able to simply define in your _darcs/prefs/defaults something like
>
> apply run-posthook
> apply posthook echo $DARCS_PATCHES | mail -s 'Patch applied' user@host.com

>From the documentation:

  DARCS_PATCHES contains a human-readable summary of the patches being
  acted upon, and DARCS_FILES contains a list of the files affected, one
  file per line.

Is it possible to add DARCS_HASHES (or similar) which contains the
hash(es) of the patch being acted upon?  In this way, you could have

  apply posthook darcs $COMMAND --patch $DARCS_HASHES | mail ...

This will let the end user finely controls the mail output (which is
something I'd like to).

Thx, bye,
Gismo / Luca