Allow killing off the *Tree* buffer

* gnus-salt.el (gnus-highlight-selected-tree): Check whether the Tree
buffer exists before using it (bug#12475).

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 5f4d00e..9e466e1 100644 (file)
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2012-12-25  Lars Ingebrigtsen  <larsi@gnus.org>
 
+       * gnus-salt.el (gnus-highlight-selected-tree): Check whether the Tree
+       buffer exists before using it (bug#12475).
+
        * gnus-agent.el (gnus-agent-fetch-articles): Don't fetch articles from
        offline groups (bug#11937).
 

diff --git a/lisp/gnus-salt.el b/lisp/gnus-salt.el
index 5ac2c55..cb4101b 100644 (file)
--- a/lisp/gnus-salt.el
+++ b/lisp/gnus-salt.el
@@ -828,31 +828,33 @@ Two predefined functions are available:
 
 (defun gnus-highlight-selected-tree (article)
   "Highlight the selected article in the tree."
-  (let ((buf (current-buffer))
-       region)
-    (set-buffer gnus-tree-buffer)
-    (when (setq region (gnus-tree-article-region article))
-      (when (or (not gnus-selected-tree-overlay)
-               (gnus-extent-detached-p gnus-selected-tree-overlay))
-       ;; Create a new overlay.
-       (gnus-overlay-put
-        (setq gnus-selected-tree-overlay
-              (gnus-make-overlay (point-min) (1+ (point-min))))
-        'face gnus-selected-tree-face))
-      ;; Move the overlay to the article.
-      (gnus-move-overlay
-       gnus-selected-tree-overlay (goto-char (car region)) (cdr region))
-      (gnus-tree-minimize)
-      (gnus-tree-recenter)
-      (let ((selected (selected-window)))
-       (when (gnus-get-buffer-window (set-buffer gnus-tree-buffer) t)
-         (select-window (gnus-get-buffer-window (set-buffer gnus-tree-buffer) t))
-         (gnus-horizontal-recenter)
-         (select-window selected))))
-;; If we remove this save-excursion, it updates the wrong mode lines?!?
-    (with-current-buffer gnus-tree-buffer
-      (gnus-set-mode-line 'tree))
-    (set-buffer buf)))
+  (when (buffer-live-p gnus-tree-buffer)
+    (let ((buf (current-buffer))
+         region)
+      (set-buffer gnus-tree-buffer)
+      (when (setq region (gnus-tree-article-region article))
+       (when (or (not gnus-selected-tree-overlay)
+                 (gnus-extent-detached-p gnus-selected-tree-overlay))
+         ;; Create a new overlay.
+         (gnus-overlay-put
+          (setq gnus-selected-tree-overlay
+                (gnus-make-overlay (point-min) (1+ (point-min))))
+          'face gnus-selected-tree-face))
+       ;; Move the overlay to the article.
+       (gnus-move-overlay
+        gnus-selected-tree-overlay (goto-char (car region)) (cdr region))
+       (gnus-tree-minimize)
+       (gnus-tree-recenter)
+       (let ((selected (selected-window)))
+         (when (gnus-get-buffer-window (set-buffer gnus-tree-buffer) t)
+           (select-window
+            (gnus-get-buffer-window (set-buffer gnus-tree-buffer) t))
+           (gnus-horizontal-recenter)
+           (select-window selected))))
+      ;; If we remove this save-excursion, it updates the wrong mode lines?!?
+      (with-current-buffer gnus-tree-buffer
+       (gnus-set-mode-line 'tree))
+      (set-buffer buf))))
 
 (defun gnus-tree-highlight-article (article face)
   (with-current-buffer (gnus-get-tree-buffer)