* lisp/subr.el (y-or-n-p): Handle empty prompts.

Fixes: debbugs:14770

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 2204d474be95573dda28c89da44a3bc313043093..1cf0d190130d6c8b9e2b799b8e999a924059b376 100644 (file)
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-07-03  Glenn Morris  <rgm@gnu.org>
+
+       * subr.el (y-or-n-p): Handle empty prompts.  (Bug#14770)
+
 2013-05-26  Fabián Ezequiel Gallina  <fgallina@gnu.org>
 
        * progmodes/python.el (python-indent-block-enders): Add break,

diff --git a/lisp/subr.el b/lisp/subr.el
index 88f27c7576409e71b10bcc7fad78071a62ce6f34..0434e3856f99ba39309270fd996a28ea8bce7113 100644 (file)
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2352,7 +2352,8 @@ is nil and `use-dialog-box' is non-nil."
     (cond
      (noninteractive
       (setq prompt (concat prompt
-                           (if (eq ?\s (aref prompt (1- (length prompt))))
+                           (if (or (zerop (length prompt))
+                                   (eq ?\s (aref prompt (1- (length prompt)))))
                                "" " ")
                            "(y or n) "))
       (let ((temp-prompt prompt))
@@ -2369,7 +2370,8 @@ is nil and `use-dialog-box' is non-nil."
            (x-popup-dialog t `(,prompt ("Yes" . act) ("No" . skip)))))
      (t
       (setq prompt (concat prompt
-                           (if (eq ?\s (aref prompt (1- (length prompt))))
+                           (if (or (zerop (length prompt))
+                                   (eq ?\s (aref prompt (1- (length prompt)))))
                                "" " ")
                            "(y or n) "))
       (while