2012-02-17 Tassilo Horn <tassilo@member.fsf.org>

	* saveplace.el (save-place-ignore-files-regexp): New variable
	allowing for excluding files from saving their location.  The
	default value matches the temporary commit message editing files
	from Git, SVN, Bazaar, and Mercurial.
	(save-place-to-alist): Use it.

1 files changed, 22 insertions, 14 deletions

diff --git a/lisp/saveplace.el b/lisp/saveplace.el
index 0588bf258a7..5850d2b8d33 100644
--- a/lisp/saveplace.el
+++ b/lisp/saveplace.el
@@ -130,6 +130,13 @@ Files for which such a check may be inconvenient include those on
 removable and network volumes."
   :type 'regexp :group 'save-place)
 
+(defcustom save-place-ignore-files-regexp
+  "\\(?:COMMIT_EDITMSG\\|hg-editor-[[:alnum:]]+\\.txt\\|svn-commit\\.tmp\\|bzr_log\\.[[:alnum:]]+\\)$"
+  "Regexp matching files for which no location should be recorded.
+Useful for temporary file such as commit message files that are
+automatically created by the VCS."
+  :type 'regexp :group 'save-place)
+
 (defun toggle-save-place (&optional parg)
   "Toggle whether to save your place in this file between sessions.
 If this mode is enabled, point is recorded when you kill the buffer
@@ -160,20 +167,21 @@ To save places automatically in all files, put this in your `.emacs' file:
   ;; file.  If not, do so, then feel free to modify the alist.  It
   ;; will be saved again when Emacs is killed.
   (or save-place-loaded (load-save-place-alist-from-file))
-  (if buffer-file-name
-      (progn
-        (let ((cell (assoc buffer-file-name save-place-alist))
-	      (position (if (not (eq major-mode 'hexl-mode))
-			    (point)
-			  (with-no-warnings
-			    (1+ (hexl-current-address))))))
-          (if cell
-              (setq save-place-alist (delq cell save-place-alist)))
-	  (if (and save-place
-		   (not (= position 1)))  ;; Optimize out the degenerate case.
-	      (setq save-place-alist
-		    (cons (cons buffer-file-name position)
-			  save-place-alist)))))))
+  (when (and buffer-file-name
+	     (not (string-match save-place-ignore-files-regexp
+				buffer-file-name)))
+    (let ((cell (assoc buffer-file-name save-place-alist))
+	  (position (if (not (eq major-mode 'hexl-mode))
+			(point)
+		      (with-no-warnings
+			(1+ (hexl-current-address))))))
+      (if cell
+	  (setq save-place-alist (delq cell save-place-alist)))
+      (if (and save-place
+	       (not (= position 1)))  ;; Optimize out the degenerate case.
+	  (setq save-place-alist
+		(cons (cons buffer-file-name position)
+		      save-place-alist))))))
 
 (defun save-place-forget-unreadable-files ()
   "Remove unreadable files from `save-place-alist'.