Re: Suggestion: vc-hooks.el: Make vc-handled-backends more conservative?

[Stefan Monnier]

> Consider an environment where your home dir (and all users home
> dirs) come from nfs and are visible as /home/user

Hmm... now that I look at the code I see that the optimization I had put for
this common case is actually missing.  Can you try the patch below, see if
it helps?


        Stefan


--- orig/lisp/vc-hooks.el
+++ mod/lisp/vc-hooks.el
@@ -52,11 +52,13 @@
 (defvar vc-header-alist ())
 (make-obsolete-variable 'vc-header-alist 'vc-BACKEND-header)
 
-(defvar vc-ignore-dir-regexp "\\`\\([\\/][\\/]\\|/net/\\|/afs/\\)\\'"
- "Regexp matching directory names that are not under VC's control.
+(defcustom vc-ignore-dir-regexp "\\`\\([\\/][\\/]\\|/net/\\|/afs/\\)\\'"
+  "Regexp matching directory names that are not under VC's control.
 The default regexp prevents fruitless and time-consuming attempts
 to determine the VC status in directories in which filenames are
-interpreted as hostnames.")
+interpreted as hostnames."
+  :type 'regexp
+  :group 'vc)
 
 (defcustom vc-handled-backends '(RCS CVS SVN SCCS Arch MCVS)
   ;; Arch and MCVS come last because they are per-tree rather than per-dir.
@@ -308,6 +310,9 @@
   "Find the root of a checked out project.
 The function walks up the directory tree from FILE looking for WITNESS.
 If WITNESS if not found, return nil, otherwise return the root."
+  ;; Represent /home/luser/foo as ~/foo so that we don't try to look for
+  ;; witnesses in /home or in /.
+  (setq file (abbreviate-file-name file))
   (let ((root nil))
     (while (not (or root
                    (equal file (setq file (file-name-directory file)))