#774709 clarify "unknown date format" message

Package:
git
Source:
git
Description:
fast, scalable, distributed revision control system
Submitter:
Ian Jackson
Date:
2015-01-06 16:15:05 UTC
Severity:
minor
#774709#5
Date:
2015-01-06 16:05:55 UTC
From:
To:
$ git-show --date '6 months ago' xen/Makefile
fatal: unknown date format 6 months ago
$ git-show --date 'now -6 months' xen/Makefile
fatal: unknown date format now -6 months
$ git-show --date "`date -d 'now -6 months'`" xen/Makefile
fatal: unknown date format Sun Jul  6 17:01:31 BST 2014
$ git-show --date "`date -R -d 'now -6 months'`" xen/Makefile
fatal: unknown date format Sun, 06 Jul 2014 17:01:47 +0100
$ git-show --date "`date --iso-8601 -d 'now -6 months'`" xen/Makefile
fatal: unknown date format 2014-07-06
$ git-show --date "`date --iso-8601=minutes -d 'now -6 months'`" xen/Makefile
fatal: unknown date format 2014-07-06T17:02+0100
$ git-show --date "`date --rfc-3339=seconds -d 'now -6 months'`" xen/Makefile
fatal: unknown date format 2014-07-06 17:03:01+01:00
$ git-show --date "`date --rfc-3339=date -d 'now -6 months'`" xen/Makefile
fatal: unknown date format 2014-07-06
$

IMO git should accept all of these, not none of them.  If that's not
acceptable it should at least accept ISO-8601.

Ian.
#774709#10
Date:
2015-01-06 16:11:54 UTC
From:
To:
Ian Jackson writes ("git does not accept any date format from date(1) !"):

It turns out that I meant something different, and foolishly thought
that --date would take a date.  It doesn't it takes a string
requesting a date format.

I would have been saved some flailing if the error message had
something like
  unknown date output format specification `blah'

Thanks,
Ian.