Hi,

there seems to be an incompatibility between changes and diff. 
Apparently, when combining --patch and --last diff just takes looks at 
the last one, iso. logically ANDing them.

eg.

muurbloem:~/vc/gub$ darcs changes --patch 'resolve' --last=50  |head
Tue Jan 10 12:48:27 CET 2006  hanwen@xs4all.nl
   * resolve.
muurbloem:~/vc/gub$ darcs diff --patch 'resolve' --last=50  |head
Tue Jan 10 12:48:27 CET 2006  hanwen@xs4all.nl
   * resolve.
Tue Jan 10 12:46:33 CET 2006  hanwen@xs4all.nl
   * use Freetype__mingw, but excise reconfigure hack.
Tue Jan 10 11:46:03 CET 2006  hanwen@xs4all.nl
   * d'oh. pre_install_libtool_fuckup() depends on build_platform, not
   target platform.
Tue Jan 10 09:43:17 CET 2006  janneke@gnu.org
   tagged success-make_linux_from_linux-20060110015946
Tue Jan 10 06:26:44 CET 2006  hanwen@xs4all.nl
muurbloem:~/vc/gub$

There is not an inconsistency here, just confusion. 

Some darcs commands support --patch (singular), and others have --patches
(plural) depending on what makes sense in each case. 

Which darcs diff, you can either review the diff for a single patch, or the diff
betweeen two points in history. It's not nearly as a common to want to express
"show me all the diffs of the patches that match the pattern blue". 

On the other hand, it's more likely to want to express "show me all the
changelog entries related to to the pattern "RT#1234". 

In your example, you have done something unusual: In darcs diff you have
combined an option used to select a single patch for diffing, and another select
an end-point for differing against the current state of the tree. 

I think perhaps darcs should throw an error in this case and say something like
"using --patch and --last at the same time with the 'diff' command doesn't make
sense. Use --from-patch to create a diff from this patch to the present, or use
 just '--patch' to view this specific patch.

On Tue, Jan 08, 2008 at 01:27:57AM -0000, Mark Stosberg wrote:
> I think perhaps darcs should throw an error in this case and say something like
> "using --patch and --last at the same time with the 'diff' command doesn't make
> sense. Use --from-patch to create a diff from this patch to the present, or use
>  just '--patch' to view this specific patch.

This analysis sounds right to me.

David