* vc.el (vc-dired-ignorable-p, vc-dired-hook): Speed optimization;

use completion-ignored-extensions to detect files that should be
ignorted in VC-Dired listings, heading off lots of expensive calls
to (vc-state).

2 files changed, 24 insertions, 3 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index b1878cef3f5..a5f568db299 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2007-12-27  Eric S. Raymond  <esr@snark.thyrsus.com>
+
+        * vc.el (vc-dired-ignorable-p, vc-dired-hook): Speed optimization;
+        use completion-ignored-extensions to detect files that should be
+        ignorted in VC-Dired listings, heading off lots of expensive calls
+        to (vc-state).
+
 2007-12-27  Vinicius Jose Latorre  <viniciusjl@ig.com.br>
 
         * ps-print.el (ps-mark-active-p): Fun returned back.
@@ -6,8 +13,8 @@
 
 2007-12-27  Eric S. Raymond  <esr@snark.thyrsus.com>
 
-        * (vc.el, vc-sccs.el, vc-rcs.el, vc-cs.el, vc-mcvs.el): Put
-        machinery in place to support editing of change comments
+        * vc.el, vc-sccs.el, vc-rcs.el, vc-cs.el, vc-mcvs.el: Put
+        new machinery in place to support editing of change comments
         with 'e' in a log-view buffer.  Not documented yet as this
         only works for SCCS, RCS, and maybe CVS if you have admin
         privileges.  When we have backend support for Subversion and
diff --git a/lisp/vc.el b/lisp/vc.el
index 3d1132aab77..eca24b124d0 100644
--- a/lisp/vc.el
+++ b/lisp/vc.el
@@ -2327,6 +2327,16 @@ This code, like dired, assumes UNIX -l format."
       (replace-match (substring (concat vc-info "          ") 0 10)
                      t t nil 1)))
 
+(defun vc-dired-ignorable-p (filename)
+  "Should FILENAME be ignored in VC-Dired listings?"
+  (catch t 
+    (dolist (ignorable completion-ignored-extensions)
+      (let ((ext (substring filename 
+                              (- (length filename)
+                                 (length ignorable)))))
+        (if (string= ignorable ext) (throw t t))))
+    nil))
+
 (defun vc-dired-hook ()
   "Reformat the listing according to version control.
 Called by dired after any portion of a vc-dired buffer has been read in."
@@ -2372,7 +2382,11 @@ Called by dired after any portion of a vc-dired buffer has been read in."
            (t
             (vc-dired-reformat-line nil)
             (forward-line 1))))
-         ;; ordinary file
+         ;; try to head off calling the expensive state query -
+         ;; ignore object files, TeX intermediate files, and so forth.
+         ((vc-dired-ignorable-p filename)
+          (dired-kill-line))
+         ;; ordinary file -- call the (possibly expensive) state query
          ((and (vc-backend filename)
                (not (and vc-dired-terse-mode
                          (vc-up-to-date-p filename))))