Bug#438661: "apt-cache --no-all-versions" doesn't display the candidate version

[Paul Kimoto <kimoto@lightlink.com>]

Package: apt
Version: 0.6.46.4-0.1

I have a system with both stable and testing in /e/a/sources.list, plus a
higher priority for stable specified in /e/a/preferences.  Things seem to
have generally worked for quite a while in the expected manner.  However,
the behavior of "apt-cache --no-all-versions show PACKAGE" does not match
the description in the apt-cache(8) man page:

:         If --no-all-versions is
:         specified, only the candidate version will displayed (the one which
:         would be selected for installation). This option is only applicable
:         to the show command

$ apt-cache policy lsb-base
lsb-base:
  Installed: 3.1-23.1
  Candidate: 3.1-23.2etch1
  Version table:
     3.1-24 0
        500 http://http.us.debian.org testing/main Packages
     3.1-23.2etch1 0
        550 http://http.us.debian.org stable/main Packages
 *** 3.1-23.1 0
        100 /var/lib/dpkg/status
$ apt-cache --no-all-versions show lsb-base | grep Version:
Version: 3.1-24

That is, "apt-cache policy" picks the right candidate version, but
"apt-cache --no-all-versions show" doesn't.