Avoid deleting ibuffer named filters by default.

* lisp/ibuf-ext.el (ibuffer-filter-disable): New arg for deleting
filter groups.
(ibuffer-included-in-filter-p-1): Use it.  Suggested by Noam
Postavsky.

Fixes: debbugs:8804

2 files changed, 16 insertions, 6 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 07f45b34a54..510f594465c 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2011-08-14  Chong Yidong  <cyd@stupidchicken.com>
+
+        * ibuf-ext.el (ibuffer-filter-disable): New arg for deleting
+        filter groups.
+        (ibuffer-included-in-filter-p-1): Use it.  Suggested by Noam
+        Postavsky (Bug#8804).
+
 2011-08-12  Juanma Barranquero  <lekktu@gmail.com>
 
         * startup.el (argi): Declare as global variable (bug#9275).
diff --git a/lisp/ibuf-ext.el b/lisp/ibuf-ext.el
index f4b729458e6..073efaeee2a 100644
--- a/lisp/ibuf-ext.el
+++ b/lisp/ibuf-ext.el
@@ -505,7 +505,7 @@ To evaluate a form without viewing the buffer, see `ibuffer-do-eval'."
               (assoc (cdr filter)
                      ibuffer-saved-filters)))
          (unless data
-           (ibuffer-filter-disable)
+           (ibuffer-filter-disable t)
            (error "Unknown saved filter %s" (cdr filter)))
          (ibuffer-included-in-filters-p buf (cadr data))))
       (t
@@ -514,7 +514,7 @@ To evaluate a form without viewing the buffer, see `ibuffer-do-eval'."
          ;; filterdat should be like (TYPE DESCRIPTION FUNC)
          ;; just a sanity check
         (unless filterdat
-          (ibuffer-filter-disable)
+          (ibuffer-filter-disable t)
           (error "Undefined filter %s" (car filter)))
         (not
          (not
@@ -768,11 +768,14 @@ The value from `ibuffer-saved-filter-groups' is used."
   (ibuffer-update nil t))
 
 ;;;###autoload
-(defun ibuffer-filter-disable ()
-  "Disable all filters currently in effect in this buffer."
+(defun ibuffer-filter-disable (&optional delete-filter-groups)
+  "Disable all filters currently in effect in this buffer.
+With optional arg DELETE-FILTER-GROUPS non-nil, delete all filter
+group definitions by setting `ibuffer-filter-groups' to nil."
   (interactive)
-  (setq ibuffer-filtering-qualifiers nil
-        ibuffer-filter-groups nil)
+  (setq ibuffer-filtering-qualifiers nil)
+  (if delete-filter-groups
+      (setq ibuffer-filter-groups nil))
   (let ((buf (ibuffer-current-buffer)))
     (ibuffer-update nil t)
     (when buf