"ignore Y" in make_lispy_event

"ignore Y" in make_lispy_event

[Eli Zaretskii]

A comment in keyboard.c:make_lispy_event says:

      /* For mode line and header line clicks, return X relative to
	 the left window edge; ignore Y.  Use mode_line_string to look
	 for a string on the click position.  */

The code below that, introduced in revno 102413, indeed "ignores Y",
in that it leaves yret at its initial zero value.  This breaks mouse
clicks on the mode line that pop up menus via x-popup-menu: the menu
is popped at the top of the frame/window, instead of at the place of
the click.

Chong, did you have good reasons to "ignore Y"?  If not, the simple
patch below restores the correct behavior of the popup menus:

=== modified file 'src/keyboard.c'
--- src/keyboard.c	2010-11-20 14:51:25 +0000
+++ src/keyboard.c	2010-11-26 13:33:31 +0000
@@ -5305,6 +5305,7 @@ make_lispy_position (struct frame *f, Li
 	    ? PT : XMARKER (w->pointm)->charpos;
 
 	  xret = wx;
+	  yret = wy;
 	}
       /* For fringes and margins, Y is relative to the area's (and the
 	 window's) top edge, while X is meaningless.  */

Re: "ignore Y" in make_lispy_event

[Chong Yidong]

Eli Zaretskii <eliz@gnu.org> writes:

> A comment in keyboard.c:make_lispy_event says:
>
>       /* For mode line and header line clicks, return X relative to
> 	 the left window edge; ignore Y.  Use mode_line_string to look
> 	 for a string on the click position.  */
>
> The code below that, introduced in revno 102413, indeed "ignores Y",
> in that it leaves yret at its initial zero value.  This breaks mouse
> clicks on the mode line that pop up menus via x-popup-menu: the menu
> is popped at the top of the frame/window, instead of at the place of
> the click.
>
> Chong, did you have good reasons to "ignore Y"?  If not, the simple
> patch below restores the correct behavior of the popup menus:

I was working using the Elisp manual as a spec:

    X, Y
          These are the pixel coordinates of the click, relative to the
          top left corner of WINDOW, which is `(0 . 0)'.  For the mode
          or header line, Y does not have meaningful data.  For the
          vertical line, X does not have meaningful data.

If there is existing code that relies on undocumented behavior, then we
should indeed restore the old behavior, and document it in the manual.

Re: "ignore Y" in make_lispy_event

[Eli Zaretskii]

> From: Chong Yidong <cyd@stupidchicken.com>
> Cc: emacs-devel@gnu.org
> Date: Fri, 26 Nov 2010 10:47:12 -0500
> 
> I was working using the Elisp manual as a spec:
> 
>     X, Y
>           These are the pixel coordinates of the click, relative to the
>           top left corner of WINDOW, which is `(0 . 0)'.  For the mode
>           or header line, Y does not have meaningful data.  For the
>           vertical line, X does not have meaningful data.
> 
> If there is existing code that relies on undocumented behavior, then we
> should indeed restore the old behavior, and document it in the manual.

Will do, thanks for the pointer.

Re: "ignore Y" in make_lispy_event

[Eli Zaretskii]

> Date: Fri, 26 Nov 2010 18:11:12 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: emacs-devel@gnu.org
> 
> > From: Chong Yidong <cyd@stupidchicken.com>
> > Cc: emacs-devel@gnu.org
> > Date: Fri, 26 Nov 2010 10:47:12 -0500
> > 
> > I was working using the Elisp manual as a spec:
> > 
> >     X, Y
> >           These are the pixel coordinates of the click, relative to the
> >           top left corner of WINDOW, which is `(0 . 0)'.  For the mode
> >           or header line, Y does not have meaningful data.  For the
> >           vertical line, X does not have meaningful data.
> > 
> > If there is existing code that relies on undocumented behavior, then we
> > should indeed restore the old behavior, and document it in the manual.
> 
> Will do, thanks for the pointer.

Done.