From: Chong Yidong <cyd@stupidchicken.com>
Date: Sat, 2 Jul 2011 23:40:04 +0000 (-0400)
Subject: Fix corner case in prefix-arg handling for mouse events (Bug#1586).
X-Git-Tag: emacs-pretest-24.0.90~104^2~152^2~227
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=7a8e04f79efdefcb3eb7cb2cf5dbb454a78cf24e;p=emacs.git

Fix corner case in prefix-arg handling for mouse events (Bug#1586).

* src/keyboard.c (command_loop_1): If a down-mouse event is unbound,
leave any prefix arg for the up event.
---

diff --git a/src/ChangeLog b/src/ChangeLog
index cb5d3bacba5..8b4029bd7b3 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2011-07-02  Chong Yidong  <cyd@stupidchicken.com>
+
+	* keyboard.c (command_loop_1): If a down-mouse event is unbound,
+	leave any prefix arg for the up event (Bug#1586).
+
 2011-07-02  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
 	* lread.c (syms_of_lread): Mention single symbols defined by
diff --git a/src/keyboard.c b/src/keyboard.c
index 3441f1dfd12..16300e6154c 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1539,7 +1539,18 @@ command_loop_1 (void)
 	  message_with_string ("%s is undefined", keys, 0);
 	  KVAR (current_kboard, defining_kbd_macro) = Qnil;
 	  update_mode_lines = 1;
-	  KVAR (current_kboard, Vprefix_arg) = Qnil;
+	  /* If this is a down-mouse event, don't reset prefix-arg;
+	     pass it to the command run by the up event.  */
+	  if (EVENT_HAS_PARAMETERS (last_command_event))
+	    {
+	      Lisp_Object breakdown
+		= parse_modifiers (EVENT_HEAD (last_command_event));
+	      int modifiers = XINT (XCAR (XCDR (breakdown)));
+	      if (!(modifiers & down_modifier))
+		KVAR (current_kboard, Vprefix_arg) = Qnil;
+	    }
+	  else
+	    KVAR (current_kboard, Vprefix_arg) = Qnil;
 	}
       else
 	{