Fix how the `character' custom type handles space chars.

* lisp/wid-edit.el (widget-field-value-get): New optional arg to
suppress trailing whitespace truncation.
(character): Use it.

Fixes: debbugs:2689

2 files changed, 14 insertions, 3 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 6a31a20f947..93dd50b5ecb 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2012-02-05  Chong Yidong  <cyd@gnu.org>
+
+        * wid-edit.el (widget-field-value-get): New optional arg to
+        suppress trailing whitespace truncation.
+        (character): Use it (Bug#2689).
+
 2012-02-05  Andreas Schwab  <schwab@linux-m68k.org>
 
         * progmodes/gud.el (gud-pv): Use pv instead of pv1.
diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el
index 27922327f44..61bb4db558c 100644
--- a/lisp/wid-edit.el
+++ b/lisp/wid-edit.el
@@ -1987,10 +1987,14 @@ the earlier input."
     (when (overlayp overlay)
       (delete-overlay overlay))))
 
-(defun widget-field-value-get (widget)
-  "Return current text in editing field."
+(defun widget-field-value-get (widget &optional no-truncate)
+  "Return current text in editing field.
+Normally, trailing spaces within the editing field are truncated.
+But if NO-TRUNCATE is non-nil, include them."
   (let ((from (widget-field-start widget))
-        (to (widget-field-text-end widget))
+        (to   (if no-truncate
+                  (widget-field-end widget)
+                (widget-field-text-end widget)))
         (buffer (widget-field-buffer widget))
         (secret (widget-get widget :secret))
         (old (current-buffer)))
@@ -3407,6 +3411,7 @@ To use this type, you must define :match or :match-alternatives."
   :format "%{%t%}: %v\n"
   :valid-regexp "\\`.\\'"
   :error "This field should contain a single character"
+  :value-get (lambda (w) (widget-field-value-get w t))
   :value-to-internal (lambda (_widget value)
                        (if (stringp value)
                            value