=== modified file 'lisp/gnus/ChangeLog'
--- lisp/gnus/ChangeLog 2012-09-07 04:07:00 +0000
+++ lisp/gnus/ChangeLog 2012-09-09 15:24:48 +0000
@@ -1,3 +1,9 @@
+2012-09-09  Stephen Berman  <stephen.berman@gmx.net>
+
+       * gnus-group.el (gnus-get-emacs-bug-number): New function.
+       (gnus-read-ephemeral-emacs-bug-group): Use it; change function's
+       signature and interactive spec accordingly.  Add autoload cookie.
+
 2012-09-07  Chong Yidong  <cyd@gnu.org>
 
        * gnus-util.el

=== modified file 'lisp/gnus/gnus-group.el'
--- lisp/gnus/gnus-group.el     2012-09-07 04:07:00 +0000
+++ lisp/gnus/gnus-group.el     2012-09-09 15:24:45 +0000
@@ -2498,21 +2498,54 @@
 
 (defvar debbugs-gnu-bug-number)                ; debbugs-gnu
 
-(defun gnus-read-ephemeral-emacs-bug-group (ids &optional window-conf)
-  "Browse Emacs bugs IDS as an ephemeral group."
-  (interactive (list (string-to-number
-                     (read-string "Enter bug number: "
-                                  (thing-at-point 'word) nil))))
-  (unless (listp ids)
-    (setq ids (list ids)))
-  (gnus-read-ephemeral-bug-group
-   ids
-   (cdr (assoc 'emacs gnus-bug-group-download-format-alist))
-   window-conf)
-  (when (fboundp 'debbugs-gnu-summary-mode)
-    (with-current-buffer (window-buffer (selected-window))
-      (debbugs-gnu-summary-mode 1)
-      (set (make-local-variable 'debbugs-gnu-bug-number) (car ids)))))
+(defun gnus-get-emacs-bug-number (&optional n)
+  "Return an Emacs bug number in this line, if any.
+If point is on a recognizable bug number, return it; otherwise,
+if argument N is a positive integer, return the Nth bug number in
+this line, counting from the left, or nil if there is no Nth bug
+number."
+  (save-excursion
+    ;; Get the number if point is anywhere within a string like "bug#1234",
+    ;; "Bug#1234", bug #1234", "Bug #1234", bug 1234", "Bug 1234" as well as
+    ;; "http://debbugs.gnu.org/cgi/bugreport.cgi?bug=11735"
+    (when (or (string= (thing-at-point 'word) "Bug")
+             (string= (thing-at-point 'word) "bug"))
+      (forward-word)
+      (skip-chars-forward " #="))
+    (let* ((str (thing-at-point 'word))
+          (num (if str (string-to-number str))))
+      (if (and num (not (zerop num)))
+         num
+       ;; Otherwise look for the Nth bug number on
+       ;; this line.
+       (let ((case-fold-search t))
+         (goto-char (line-beginning-position))
+         (when (re-search-forward "bug ?[#=]? ?\\([0-9]+\\)"
+                                  (line-end-position) t n)
+             (string-to-number (match-string 1))))))))
+
+;;;###autoload
+(defun gnus-read-ephemeral-emacs-bug-group (&optional n window-conf)
+  "Browse an Emacs bug report thread as an ephemeral group.
+If point is on a recognizable bug number, offer it as default;
+otherwise, offer the first, or with numerical prefix argument N,
+the Nth bug number in this line, counting from the left.  If
+there is no bug number in this line, or too few, prompt for a
+number without offering a default."
+  (interactive "P")
+  (let ((ids (read-number "Enter bug number: "
+                         (gnus-get-emacs-bug-number
+                          (if (and (integerp n) (> n 1)) n 1)))))
+    (unless (listp ids)
+      (setq ids (list ids)))
+    (gnus-read-ephemeral-bug-group
+     ids
+     (cdr (assoc 'emacs gnus-bug-group-download-format-alist))
+     window-conf)
+    (when (fboundp 'debbugs-gnu-summary-mode)
+      (with-current-buffer (window-buffer (selected-window))
+       (debbugs-gnu-summary-mode 1)
+       (set (make-local-variable 'debbugs-gnu-bug-number) (car ids))))))
 
 (defun gnus-group-jump-to-group (group &optional prompt)
   "Jump to newsgroup GROUP.