* lisp/apropos.el (apropos-read-pattern): Fix error message for empty string.

lisp/ChangeLog

+2014-02-13  Juanma Barranquero  <lekktu@gmail.com>
+
+	* apropos.el (apropos-read-pattern): When the user passes an empty
+	string, give a more helpful error message than "Wrong type
+	argument: stringp, nil".
+
 2014-02-13  Stefan Monnier  <monnier@iro.umontreal.ca>
 
 	* jit-lock.el (jit-lock-mode): Keep it disabled in indirect buffers.

lisp/apropos.el

@@ -370,7 +370,8 @@ kind of objects to search."
 	 (read-string (concat "Search for " subject " (word list or regexp): "))))
     (if (string-equal (regexp-quote pattern) pattern)
 	;; Split into words
-	(split-string pattern "[ \t]+" t)
+	(or (split-string pattern "[ \t]+" t)
+	    (user-error "No word list given"))
       pattern)))
 
 (defun apropos-parse-pattern (pattern)