[O] Bug dragging lines in tag-restricted agenda

[Thomas Morgan]

Hello, Org mode hackers.

I'm using Org-mode version 8.2 (`release_8.2-157-g1e018e' @
`/src/org-mode/lisp/') and GNU Emacs 24.3.1 (`x86_64-unknown-linux-gnu',
X toolkit, Xaw3d scroll bars) of 2013-09-21.

I started Emacs with `emacs -Q -l setup.el' (file attached).  This
opened a day agenda view.

,----
| Day-agenda (W42):
| Friday     18 October 2013
|   test-case:  Scheduled:  TODO Pick up package from post office        
:errands:
|   test-case:  Scheduled:  TODO Clean stovetop
|   test-case:  Scheduled:  TODO Buy water at store                      
:errands:
`----

I typed `/ TAB errands RET' to restrict it to items with the tag
`errands'.  The restricted view looked like this:

,----
| Day-agenda (W42):
| Friday     18 October 2013
|   test-case:  Scheduled:  TODO Pick up package from post office        
:errands:
|   test-case:  Scheduled:  TODO Buy water at store                      
:errands:
`----

I moved point to the line containing "Pick up package" and typed
`M-<down>' to drag the line forward.  Since there was a hidden line,
"Clean stovetop", between the other two, I expected no visible change,
or even better, that "Pick up package" would move below "Buy water",
like this:

,----
| Day-agenda (W42):
| Friday     18 October 2013
|   test-case:  Scheduled:  TODO Buy water at store                      
:errands:
|   test-case:  Scheduled:  TODO Pick up package from post office        
:errands:
`----

Instead, "Clean stovetop" was made visible and "Pick up package" was
moved below it:

,----
| Day-agenda (W42):
| Friday     18 October 2013
|   test-case:  Scheduled:  TODO Clean stovetop
|   test-case:  Scheduled:  TODO Pick up package from post office        
:errands:
|   test-case:  Scheduled:  TODO Buy water at store                      
:errands:
`----

I believe it is a bug for `M-<down>' to make an item visible that
doesn't match the tag in a tag-narrowed view, and I think the most
useful thing to do is to move the line beyond the next visible item.

Thanks,
Thomas

setup.el
Description: application/emacs-lisp

#+TITLE: Bug dragging lines in tag-restricted agenda

* TODO Pick up package from post office                             :errands:
  SCHEDULED: <2013-10-18 Fri>
* TODO Clean stovetop
  SCHEDULED: <2013-10-18 Fri>
* TODO Buy water at store                                           :errands:
  SCHEDULED: <2013-10-18 Fri>