Fix echoing of replayed keys.

* keyboard.c (echo_add_char): New function, factored out from
echo_char.  Don't add a space if the previous echo string was
empty.
(echo_char): Use it.
(read_key_sequence): When echoing mock input, ensure that the
trailing dash is properly added.

Fixes: debbugs:13255

2 files changed, 87 insertions, 68 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index c0c85c15ee9..3b0b295e695 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,12 @@
+2013-01-06  Chong Yidong  <cyd@gnu.org>
+
+        * keyboard.c (echo_add_char): New function, factored out from
+        echo_char.  Don't add a space if the previous echo string was
+        empty (Bug#13255).
+        (echo_char): Use it.
+        (read_key_sequence): When echoing mock input, ensure that the
+        trailing dash is properly added.
+
 2013-01-05  Eli Zaretskii  <eliz@gnu.org>
 
         * xdisp.c (dump_glyph): Align glyph data better.  Use "pD" instead
diff --git a/src/keyboard.c b/src/keyboard.c
index 8edd705135f..bc55eed1f5c 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -497,97 +497,103 @@ kset_system_key_syms (struct kboard *kb, Lisp_Object val)
 }
 
 
-/* Add C to the echo string, if echoing is going on.
-   C can be a character, which is printed prettily ("M-C-x" and all that
-   jazz), or a symbol, whose name is printed.  */
+/* Add C to the echo string, without echoing it immediately.  C can be
+   a character, which is pretty-printed, or a symbol, whose name is
+   printed.  */
 
 static void
-echo_char (Lisp_Object c)
+echo_add_char (Lisp_Object c)
 {
-  if (current_kboard->immediate_echo)
-    {
-      int size = KEY_DESCRIPTION_SIZE + 100;
-      char *buffer = alloca (size);
-      char *ptr = buffer;
-      Lisp_Object echo_string;
+  int size = KEY_DESCRIPTION_SIZE + 100;
+  char *buffer = alloca (size);
+  char *ptr = buffer;
+  Lisp_Object echo_string;
 
-      echo_string = KVAR (current_kboard, echo_string);
+  echo_string = KVAR (current_kboard, echo_string);
 
-      /* If someone has passed us a composite event, use its head symbol.  */
-      c = EVENT_HEAD (c);
+  /* If someone has passed us a composite event, use its head symbol.  */
+  c = EVENT_HEAD (c);
 
-      if (INTEGERP (c))
+  if (INTEGERP (c))
+    ptr = push_key_description (XINT (c), ptr);
+  else if (SYMBOLP (c))
+    {
+      Lisp_Object name = SYMBOL_NAME (c);
+      int nbytes = SBYTES (name);
+
+      if (size - (ptr - buffer) < nbytes)
         {
-          ptr = push_key_description (XINT (c), ptr);
+          int offset = ptr - buffer;
+          size = max (2 * size, size + nbytes);
+          buffer = alloca (size);
+          ptr = buffer + offset;
         }
-      else if (SYMBOLP (c))
-        {
-          Lisp_Object name = SYMBOL_NAME (c);
-          int nbytes = SBYTES (name);
 
-          if (size - (ptr - buffer) < nbytes)
-            {
-              int offset = ptr - buffer;
-              size = max (2 * size, size + nbytes);
-              buffer = alloca (size);
-              ptr = buffer + offset;
-            }
+      ptr += copy_text (SDATA (name), (unsigned char *) ptr, nbytes,
+                        STRING_MULTIBYTE (name), 1);
+    }
 
-          ptr += copy_text (SDATA (name), (unsigned char *) ptr, nbytes,
-                            STRING_MULTIBYTE (name), 1);
-        }
+  if ((NILP (echo_string) || SCHARS (echo_string) == 0)
+      && help_char_p (c))
+    {
+      const char *text = " (Type ? for further options)";
+      int len = strlen (text);
 
-      if ((NILP (echo_string) || SCHARS (echo_string) == 0)
-          && help_char_p (c))
+      if (size - (ptr - buffer) < len)
         {
-          const char *text = " (Type ? for further options)";
-          int len = strlen (text);
-
-          if (size - (ptr - buffer) < len)
-            {
-              int offset = ptr - buffer;
-              size += len;
-              buffer = alloca (size);
-              ptr = buffer + offset;
-            }
-
-          memcpy (ptr, text, len);
-          ptr += len;
+          int offset = ptr - buffer;
+          size += len;
+          buffer = alloca (size);
+          ptr = buffer + offset;
         }
 
-      /* Replace a dash from echo_dash with a space, otherwise
-         add a space at the end as a separator between keys.  */
-      if (STRINGP (echo_string)
-          && SCHARS (echo_string) > 1)
-        {
-          Lisp_Object last_char, prev_char, idx;
+      memcpy (ptr, text, len);
+      ptr += len;
+    }
 
-          idx = make_number (SCHARS (echo_string) - 2);
-          prev_char = Faref (echo_string, idx);
+  /* Replace a dash from echo_dash with a space, otherwise add a space
+     at the end as a separator between keys.  */
+  if (STRINGP (echo_string) && SCHARS (echo_string) > 1)
+    {
+      Lisp_Object last_char, prev_char, idx;
 
-          idx = make_number (SCHARS (echo_string) - 1);
-          last_char = Faref (echo_string, idx);
+      idx = make_number (SCHARS (echo_string) - 2);
+      prev_char = Faref (echo_string, idx);
 
-          /* We test PREV_CHAR to make sure this isn't the echoing
-             of a minus-sign.  */
-          if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
-            Faset (echo_string, idx, make_number (' '));
-          else
-            echo_string = concat2 (echo_string, build_string (" "));
-        }
-      else if (STRINGP (echo_string))
+      idx = make_number (SCHARS (echo_string) - 1);
+      last_char = Faref (echo_string, idx);
+
+      /* We test PREV_CHAR to make sure this isn't the echoing of a
+         minus-sign.  */
+      if (XINT (last_char) == '-' && XINT (prev_char) != ' ')
+        Faset (echo_string, idx, make_number (' '));
+      else
         echo_string = concat2 (echo_string, build_string (" "));
+    }
+  else if (STRINGP (echo_string) && SCHARS (echo_string) > 0)
+    echo_string = concat2 (echo_string, build_string (" "));
 
-      kset_echo_string
-        (current_kboard,
-         concat2 (echo_string, make_string (buffer, ptr - buffer)));
+  kset_echo_string
+    (current_kboard,
+     concat2 (echo_string, make_string (buffer, ptr - buffer)));
+}
+
+/* Add C to the echo string, if echoing is going on.  C can be a
+   character or a symbol.  */
 
+static void
+echo_char (Lisp_Object c)
+{
+  if (current_kboard->immediate_echo)
+    {
+      echo_add_char (c);
       echo_now ();
     }
 }
 
 /* Temporarily add a dash to the end of the echo string if it's not
-   empty, so that it serves as a mini-prompt for the very next character.  */
+   empty, so that it serves as a mini-prompt for the very next
+   character.  */
 
 static void
 echo_dash (void)
@@ -9218,8 +9224,12 @@ read_key_sequence (Lisp_Object *keybuf, int bufsize, Lisp_Object prompt,
           key = keybuf[t];
           add_command_key (key);
           if ((FLOATP (Vecho_keystrokes) || INTEGERP (Vecho_keystrokes))
-              && NILP (Fzerop (Vecho_keystrokes)))
-            echo_char (key);
+              && NILP (Fzerop (Vecho_keystrokes))
+              && current_kboard->immediate_echo)
+            {
+              echo_add_char (key);
+              echo_dash ();
+            }
         }
 
       /* If not, we should actually read a character.  */