This issue is to mention in the devguide how to create diffs with the changeset number when --git is configured on.  Perhaps this can be done via a FAQ like: "How can I get Rietveld to work with a 2.7 patch?"

Background: Currently, the devguide recommends configuring Mercurial to use --git when making diffs.  However, this causes the changeset ID to be left off of patch files and, for example, prevents Rietveld from working with patches to non-default branches.  See also this thread:

http://mail.python.org/pipermail/python-dev/2011-March/108765.html

This issue describes a couple work-arounds:

http://bz.selenic.com/show_bug.cgi?id=3761

However this is resolved, the information in the devguide should be consistent.  AFAICT, the recommendation to use hg "git" format is currently only mentioned in the Committing section (http://docs.python.org/devguide/committing.html#minimal-configuration) but not elsewhere, in particular, not http://docs.python.org/devguide/patch.html. (This was brought up in Issue10572.) Perhaps both sections could reference a FAQ entry which includes the Rietveld caveats.

> AFAICT, the recommendation to use hg "git" format is currently only mentioned in the Committing section (http://docs.python.org/devguide/committing.html#minimal-configuration) but not elsewhere, in particular, not http://docs.python.org/devguide/patch.html.

Good observation.  Personally, I think it makes sense to keep Mercurial information for both committers and non-committers (like configuring to use the "git" format) outside of the Mercurial section specific to committers.  This can be in a general Mercurial section before the section specific to committers, or else spread throughout (e.g. in the FAQ).

> This can be in a general Mercurial section before the section specific
> to committers, or else spread throughout (e.g. in the FAQ).

FWIW I'm leaning towards making the committing.rst page for committers only, and move general instructions for non-committers elsewhere.  For this issue I think it might be OK to either add a FAQ about Rietveld that also mentions the git format, or possibly include it in a new "Rietveld" section somewhere in the tracker docs (see #13963).

With the pending migration to git, this probably isn't worth the effort.