Handle nil value of ido-completion-buffer.

* lisp/ido.el (ido-set-current-directory, ido-read-internal)
(ido-choose-completion-string, ido-completion-help): Handle nil
value of ido-completion-buffer.

Fixes: debbugs:11008

2 files changed, 21 insertions, 10 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 50a9e61bf4c..1bde1a36d54 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2012-03-21  Anmol Khirbat  <anmol@khirbat.net>  (tiny change)
+
+        * ido.el (ido-set-current-directory, ido-read-internal)
+        (ido-choose-completion-string, ido-completion-help): Handle nil
+        value of ido-completion-buffer (Bug#11008).
+
 2012-03-21  Sam Steingold  <sds@gnu.org>
 
         * window.el (switch-to-prev-buffer): Do not switch to a visible
diff --git a/lisp/ido.el b/lisp/ido.el
index 5813aff0f21..dcaa8f373ce 100644
--- a/lisp/ido.el
+++ b/lisp/ido.el
@@ -1722,8 +1722,9 @@ This function also adds a hook to the minibuffer."
     (unless (and ido-enable-tramp-completion
                  (string-match "\\`/[^/]*@\\'" dir))
       (setq dir (ido-final-slash dir t))))
-  (if (get-buffer ido-completion-buffer)
-      (kill-buffer ido-completion-buffer))
+  (and ido-completion-buffer
+       (get-buffer ido-completion-buffer)
+       (kill-buffer ido-completion-buffer))
   (cond
    ((equal dir ido-current-directory)
     nil)
@@ -1736,8 +1737,9 @@ This function also adds a hook to the minibuffer."
    (t
     (ido-trace "cd" dir)
     (setq ido-current-directory dir)
-    (if (get-buffer ido-completion-buffer)
-        (kill-buffer ido-completion-buffer))
+    (and ido-completion-buffer
+         (get-buffer ido-completion-buffer)
+         (kill-buffer ido-completion-buffer))
     (setq ido-directory-nonreadable (ido-nonreadable-directory-p dir))
     (setq ido-directory-too-big (and (not ido-directory-nonreadable)
                                      (ido-directory-too-big-p dir)))
@@ -1982,8 +1984,9 @@ If INITIAL is non-nil, it specifies the initial input string."
                                         (setq ido-text-init nil))
                                       ido-completion-map nil hist))))
       (ido-trace "read-from-minibuffer" ido-final-text)
-      (if (get-buffer ido-completion-buffer)
-          (kill-buffer ido-completion-buffer))
+      (and ido-completion-buffer
+           (get-buffer ido-completion-buffer)
+           (kill-buffer ido-completion-buffer))
 
       (ido-trace "\n_EXIT_" ido-exit)
 
@@ -3837,8 +3840,9 @@ This is to make them appear as if they were \"virtual buffers\"."
 (defun ido-choose-completion-string (choice &rest ignored)
   (when (ido-active)
     ;; Insert the completion into the buffer where completion was requested.
-    (if (get-buffer ido-completion-buffer)
-        (kill-buffer ido-completion-buffer))
+    (and ido-completion-buffer
+         (get-buffer ido-completion-buffer)
+         (kill-buffer ido-completion-buffer))
     (cond
      ((ido-active t) ;; ido-use-merged-list
       (setq ido-current-directory ""
@@ -3857,7 +3861,8 @@ This is to make them appear as if they were \"virtual buffers\"."
   "Show possible completions in a *File Completions* buffer."
   (interactive)
   (setq ido-rescan nil)
-  (let ((temp-buf (get-buffer ido-completion-buffer))
+  (let ((temp-buf (and ido-completion-buffer
+                       (get-buffer ido-completion-buffer)))
         display-it full-list)
     (if (and (eq last-command this-command) temp-buf)
         ;; scroll buffer
@@ -3876,7 +3881,7 @@ This is to make them appear as if they were \"virtual buffers\"."
             (scroll-other-window))
           (set-buffer buf))
       (setq display-it t))
-    (if display-it
+    (if (and ido-completion-buffer display-it)
         (with-output-to-temp-buffer ido-completion-buffer
           (let ((completion-list (sort
                                   (cond