Handle the case when re-search-backward errs

because point is not located after rcirc-prompt-end-marker.

2 files changed, 28 insertions, 15 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 954c68c0d2f..9f9ffc7990c 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2011-03-22  Leo Liu  <sdl.web@gmail.com>
+
+        * net/rcirc.el (rcirc-completion-at-point): Return nil if point is
+        located before rcirc-prompt-end-marker.
+        (rcirc-complete): Error if point is not after rcirc prompt.
+        Handle the case when table is nil.
+
 2011-03-22  Chong Yidong  <cyd@stupidchicken.com>
 
         * custom.el (custom--inhibit-theme-enable): Make it affect only
diff --git a/lisp/net/rcirc.el b/lisp/net/rcirc.el
index 71aa0dd22bc..999a6968012 100644
--- a/lisp/net/rcirc.el
+++ b/lisp/net/rcirc.el
@@ -828,18 +828,21 @@ The list is updated automatically by `defun-rcirc-command'.")
 
 (defun rcirc-completion-at-point ()
   "Function used for `completion-at-point-functions' in `rcirc-mode'."
-  (let* ((beg (save-excursion
-                (if (re-search-backward " " rcirc-prompt-end-marker t)
-                    (1+ (point))
-                  rcirc-prompt-end-marker)))
-         (table (if (and (= beg rcirc-prompt-end-marker)
-                         (eq (char-after beg) ?/))
-                    (delete-dups
-                     (nconc
-                      (sort (copy-sequence rcirc-client-commands) 'string-lessp)
-                      (sort (copy-sequence rcirc-server-commands) 'string-lessp)))
-                  (rcirc-channel-nicks (rcirc-buffer-process) rcirc-target))))
-    (list beg (point) table)))
+  (and (rcirc-looking-at-input)
+       (let* ((beg (save-excursion
+                     (if (re-search-backward " " rcirc-prompt-end-marker t)
+                         (1+ (point))
+                       rcirc-prompt-end-marker)))
+              (table (if (and (= beg rcirc-prompt-end-marker)
+                              (eq (char-after beg) ?/))
+                         (delete-dups
+                          (nconc (sort (copy-sequence rcirc-client-commands)
+                                       'string-lessp)
+                                 (sort (copy-sequence rcirc-server-commands)
+                                       'string-lessp)))
+                       (rcirc-channel-nicks (rcirc-buffer-process)
+                                            rcirc-target))))
+         (list beg (point) table))))
 
 (defvar rcirc-completions nil)
 (defvar rcirc-completion-start nil)
@@ -848,6 +851,8 @@ The list is updated automatically by `defun-rcirc-command'.")
   "Cycle through completions from list of nicks in channel or IRC commands.
 IRC command completion is performed only if '/' is the first input char."
   (interactive)
+  (unless (rcirc-looking-at-input)
+    (error "Point not located after rcirc prompt"))
   (if (eq last-command this-command)
       (setq rcirc-completions
             (append (cdr rcirc-completions) (list (car rcirc-completions))))
@@ -855,9 +860,10 @@ IRC command completion is performed only if '/' is the first input char."
           (table (rcirc-completion-at-point)))
       (setq rcirc-completion-start (car table))
       (setq rcirc-completions
-            (all-completions (buffer-substring rcirc-completion-start
-                                               (cadr table))
-                             (nth 2 table)))))
+            (and rcirc-completion-start
+                 (all-completions (buffer-substring rcirc-completion-start
+                                                    (cadr table))
+                                  (nth 2 table))))))
   (let ((completion (car rcirc-completions)))
     (when completion
       (delete-region rcirc-completion-start (point))