Fix revert-buffer functionality of Help mode and Info.

* lisp/help-mode.el (help-mode): Set buffer-local variable
revert-buffer-function to help-mode-revert-buffer.
(help-mode-revert-buffer): New function.

* lisp/info.el (Info-revert-find-node): Check for major-mode Info-mode
before popping to "*info*" (like in other Info functions).
Keep buffer-name in old-buffer-name.  Keep Info-history-forward in
old-history-forward.  Pop to old-buffer-name or "*info*" to
recreate the killed buffer.  Set Info-history-forward from
old-history-forward.
(Info-breadcrumbs-depth): Add :group and :version.

1 files changed, 9 insertions, 2 deletions

diff --git a/lisp/info.el b/lisp/info.el
index e76a8da146e..9a30f63fff0 100644
--- a/lisp/info.el
+++ b/lisp/info.el
@@ -238,7 +238,9 @@ This only has an effect if `Info-hide-note-references' is non-nil."
 (defcustom Info-breadcrumbs-depth 4
   "Depth of breadcrumbs to display.
 0 means do not display breadcrumbs."
-  :type 'integer)
+  :version "23.1"
+  :type 'integer
+  :group 'info)
 
 (defcustom Info-search-whitespace-regexp "\\s-+"
   "If non-nil, regular expression to match a sequence of whitespace chars.
@@ -800,17 +802,22 @@ otherwise, that defaults to `Top'."
   "Go to an Info node FILENAME and NODENAME, re-reading disk contents.
 When *info* is already displaying FILENAME and NODENAME, the window position
 is preserved, if possible."
-  (pop-to-buffer "*info*")
+  (or (eq major-mode 'Info-mode) (pop-to-buffer "*info*"))
   (let ((old-filename Info-current-file)
         (old-nodename Info-current-node)
+        (old-buffer-name (buffer-name))
         (pcolumn      (current-column))
         (pline        (count-lines (point-min) (line-beginning-position)))
         (wline        (count-lines (point-min) (window-start)))
+        (old-history-forward Info-history-forward)
         (old-history  Info-history)
         (new-history  (and Info-current-file
                            (list Info-current-file Info-current-node (point)))))
     (kill-buffer (current-buffer))
+    (pop-to-buffer (or old-buffer-name "*info*"))
+    (Info-mode)
     (Info-find-node filename nodename)
+    (setq Info-history-forward old-history-forward)
     (setq Info-history old-history)
     (if (and (equal old-filename Info-current-file)
              (equal old-nodename Info-current-node))