[MERGE] Fix for 306394: warning, not error, on non-existent file.

[Karl Fogel]

Aaron Bentley <aaron at aaronbentley.com> writes:
>>> Why is it bad to error on a non-existent file?  What are the use cases?
>> 
>> From the bug's description:
>
> I read the bug's description, both now and when it was originally filed.
>  It didn't convince me or motivate me to address it.  I'm asking you,
> because it did convince and motivate you.

I can't quite tell if you're asserting that the original behavior is
better, or just wondering why I bothered to fix such a minor bug :-).

If the latter: 

Because it's one of the 4 blockers keeping the GNU Emacs project from
switching to bzr (look for bugs tagged with "emacs-adoption" to see them
all).  Specifically, the line in the bug description about:

   "This type of operation occurs in normal usage in emacs when using
    the vc-dir GUI."

(Emacs switching to bzr is something I really want to see happen; I'm
unfortunately not qualified to fix all of the blockers, but I can at
least do this one.)

If the former:

Independently of Emacs, I think warning is a better behavior here than
erroring.  The user has asked for status on a number of path names.  For
some of those names, the status is "does not exist".  Fine -- let's
report that, and report the status of the other paths as well, rather
than treat non-existence as so special that it must suppress other
statuses from being reported.

HTH,
-Karl