[PATCH 0/2] gitlog-to-changelog remove duplicate log entries

[Gary V. Vaughan]

On occasions, it's possible to end up with a bunch of duplicate
entries in the git log - which is fine and proper there, but no so
good in the gitlog-to-changelog generated ChangeLog.

Previously I had been removing them from the ChangeLog with, e.g.

  9333e74fc7b76a11ed04a19343eb5dd75a1035f3
  # Date:   Sun Feb 19 16:21:00 2012 -0600
  # Elide duplicate log entries.
  s|^[\s\S]*$$||

This (correctly) warns about an empty commit log message, but never-
the-less adds a header to the generated ChangeLog:

  2012-02-20  Peter O'Gorman  <address@hidden>

        maint: Deleted unneeded gitlog-to-changelog patch
        * gl/build-aux/gitlog-to-changelog.diff: Delete.

  2012-02-19  Gary V. Vaughan  <address@hidden>

  2012-02-02  Roumen Petrov  <address@hidden>  (tiny change)

        fixup: restore EXPORTS test

With the first patch applied, gitlog-to-changelog continues to issue
the empty commit warning, but doesn't emit the orphaned headers.

However, after a while, the number of 'empty commit log' warnings can
multiply to the point where it's hard to notice any genuine new ones
among the noise (Libtool currently has 55 -- don't even ask!). Hence
the second patch, which sidesteps the problem by adding a new tag for
marking deliberately removed commit logs, which are then elided
silently.

It's pretty likely you won't know that you will want to ignore your
bogus duplicate log messages when you push, but you can use git-log-fix
to edit the tag into the entry.  Libtool now has, e.g.

  9333e74fc7b76a11ed04a19343eb5dd75a1035f3
  # Date:   Sun Feb 19 16:21:00 2012 -0600
  # Elide duplicate log entries.
  s|$|Omit-from-ChangeLog: Yes|

I think these patches are useful outside of libtool.  Okay to push?

Cheers,
-- 
Gary V. Vaughan (gary AT gnu DOT org)