Bug querying implementation for report-emacs-bug

[Tassilo Horn <tassilo@member.fsf.org>]

Hi all,

I've just pushed a first implementation for an existing bug querying
mechanism to query the bugs database for existing bugs given a few
keywords (r102443).  Eventually, that should become the first thing a
user has to do when she wants to report a bug using M-x
report-emacs-bug.

Right now, it's not yet integrated with that function, but you can
test-drive the querying stuff like that:

  1. M-x report-emacs-bug-query-existing-bugs RET next-line RET

  2. A buffer *Existing Emacs Bugs* will show up presenting all bugs
     that match the keywords given above.  I use the widget library, so
     that one can easily chose an existing bug with a combo box thing.
     For each existing bug, clicking its URL will fire up a browser to
     the web interface.

     One annoyance here is that only active url-link widget can be
     clicked.  That's my first use of emacs widgets, so maybe someone
     can fix that.  (There's a FIXME in the code).

  3. Finally, the user has the choice to append his report to an
     existing bug, report a new one, or quit the reporting procedure (in
     case she found out, that the bug is known, and she cannot provide
     additional information).

     Except the quitting, there're no actual implementations for the
     former two actions.  But basically, that has only to set the right
     email address for the report, i.e., the usual address for new
     reports and the address including the bug number for appending to
     existing reports.

It all seems to work pretty well, except that the querying on the server
side is somehow a bit, well, sloppy.  For example, when I search for
"column", I can find some bugs including

  #971 [n|  |  ] [emacs] 23.0.60; next-line, previous-line and
   goal-column

When I search for "next-line previous-line goal-column" (without the
quotes), I find *nothing*...

When I search for "next-line, previous-line and goal-column" I get 4
bugs again.

Why does that comma and the "and" make any difference?

Bye,
Tassilo