bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Gerd Möllmann]

With master, emacs -Q. Move the mouse to the "All" displayed in the
mode-line. The last 'l' is not highlighted.

This seems to be the case for a longer time.
cb0b6a405706f6367d9adfb3ee447590c2a0876f from around 4 months ago
already shows this. Emacs 30 works as expected.

Sorry, I can't bisect this at the moment.

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Eli Zaretskii]

> From: Gerd Möllmann <gerd.moellmann@gmail.com>
> Date: Sun, 02 Feb 2025 17:03:14 +0100
> 
> With master, emacs -Q. Move the mouse to the "All" displayed in the
> mode-line. The last 'l' is not highlighted.
> 
> This seems to be the case for a longer time.
> cb0b6a405706f6367d9adfb3ee447590c2a0876f from around 4 months ago
> already shows this. Emacs 30 works as expected.
> 
> Sorry, I can't bisect this at the moment.

It happened sometime in August last year, so my prime suspect is
71505b723c9fb9de20f6d38be7c73d595e9be3ce, since that part of the mode
line uses 'min-width' display property.

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Gerd Möllmann]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Gerd Möllmann <gerd.moellmann@gmail.com>
>> Date: Sun, 02 Feb 2025 17:03:14 +0100
>> 
>> With master, emacs -Q. Move the mouse to the "All" displayed in the
>> mode-line. The last 'l' is not highlighted.
>> 
>> This seems to be the case for a longer time.
>> cb0b6a405706f6367d9adfb3ee447590c2a0876f from around 4 months ago
>> already shows this. Emacs 30 works as expected.
>> 
>> Sorry, I can't bisect this at the moment.
>
> It happened sometime in August last year, so my prime suspect is
> 71505b723c9fb9de20f6d38be7c73d595e9be3ce, since that part of the mode
> line uses 'min-width' display property.

Confirmed, 71505b723c9fb9de20f6d38be7c73d595e9be3ce it is.

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Gerd Möllmann]

Gerd Möllmann <gerd.moellmann@gmail.com> writes:

> Confirmed, 71505b723c9fb9de20f6d38be7c73d595e9be3ce it is.

Don't know if this is directly related, but playing with

  (defun foo ()
    (interactive)
    (with-current-buffer (get-buffer-create "*foo*")
      (erase-buffer)
      (insert "12345")
      (put-text-property (point-min) (point)
                         'display '(min-width (5)))
      (put-text-property (point-min) (point)
                         'mouse-face 'highlight)
      (insert "abc")
      (display-buffer (current-buffer))))

shows that if the text, in this case "12345", is longer than min-width, a
space is added, and if it's equal to min-width, no space is added.

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Gerd Möllmann]

[-- Attachment #1: Type: text/plain, Size: 895 bytes --]

Gerd Möllmann <gerd.moellmann@gmail.com> writes:

> Gerd Möllmann <gerd.moellmann@gmail.com> writes:
>
>> Confirmed, 71505b723c9fb9de20f6d38be7c73d595e9be3ce it is.
>
> Don't know if this is directly related, but playing with
>
>   (defun foo ()
>     (interactive)
>     (with-current-buffer (get-buffer-create "*foo*")
>       (erase-buffer)
>       (insert "12345")
>       (put-text-property (point-min) (point)
>                          'display '(min-width (5)))
>       (put-text-property (point-min) (point)
>                          'mouse-face 'highlight)
>       (insert "abc")
>       (display-buffer (current-buffer))))
>
> shows that if the text, in this case "12345", is longer than min-width, a
> space is added, and if it's equal to min-width, no space is added.

That attached patch fixes both the above problem and the the one in the
mode-line.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-Fix-min-width-display-spec-handling-bug-76014.patch --]
[-- Type: text/x-patch, Size: 2026 bytes --]

From 711f21b659633fb05b81f43f3e81391e5988fe3a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gerd=20M=C3=B6llmann?= <gerd@gnu.org>
Date: Tue, 4 Feb 2025 06:09:52 +0100
Subject: [PATCH] Fix min-width display spec handling (bug#76014)

* src/xdisp.c (display_min_width): Take into account that the output may
already be longer than the specified min-width.
---
 src/xdisp.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/xdisp.c b/src/xdisp.c
index ed4a5564427..72311362035 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -5650,7 +5650,7 @@ get_display_property (ptrdiff_t charpos, Lisp_Object prop, Lisp_Object object)
 
 /* Handle 'display' property '(min-width (WIDTH))' at CHARPOS in OBJECT.
    OBJECT can be a buffer (or nil, which means the current buffer) or a
-   string.  MIN_WIDTH is the value of min-width spec that we expect to
+   string.  WIDTH_SPEC is the value of min-width spec that we expect to
    process.  */
 static void
 display_min_width (struct it *it, ptrdiff_t charpos,
@@ -5696,8 +5696,9 @@ display_min_width (struct it *it, ptrdiff_t charpos,
                  a stretch that ends beyond the visible portion of the
                  window if we are truncating screen lines.  If we are
                  requested to do that, some Lisp program went awry.  */
-	      if (!(it->line_wrap == TRUNCATE
-		    && it->current_x + width > it->last_visible_x))
+	      if (width > 0
+		  && !(it->line_wrap == TRUNCATE
+		       && it->current_x + width > it->last_visible_x))
 		w = list1 (make_int (width));
 	    }
 	  else
@@ -5708,8 +5709,9 @@ display_min_width (struct it *it, ptrdiff_t charpos,
 					  NULL, true, NULL);
 	      width -= (it->current_x - it->min_width_start) /
 		FRAME_COLUMN_WIDTH (it->f);
-	      if (!(it->line_wrap == TRUNCATE
-		    && it->current_x + width > it->last_visible_x))
+	      if (width > 0
+		  && !(it->line_wrap == TRUNCATE
+		       && it->current_x + width > it->last_visible_x))
 		w = make_int (width);
 	    }
 
-- 
2.48.1

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Eli Zaretskii]

> From: Gerd Möllmann <gerd.moellmann@gmail.com>
> Cc: 76014@debbugs.gnu.org
> Date: Tue, 04 Feb 2025 06:12:57 +0100
> 
> Gerd Möllmann <gerd.moellmann@gmail.com> writes:
> 
> > Gerd Möllmann <gerd.moellmann@gmail.com> writes:
> >
> >> Confirmed, 71505b723c9fb9de20f6d38be7c73d595e9be3ce it is.
> >
> > Don't know if this is directly related, but playing with
> >
> >   (defun foo ()
> >     (interactive)
> >     (with-current-buffer (get-buffer-create "*foo*")
> >       (erase-buffer)
> >       (insert "12345")
> >       (put-text-property (point-min) (point)
> >                          'display '(min-width (5)))
> >       (put-text-property (point-min) (point)
> >                          'mouse-face 'highlight)
> >       (insert "abc")
> >       (display-buffer (current-buffer))))
> >
> > shows that if the text, in this case "12345", is longer than min-width, a
> > space is added, and if it's equal to min-width, no space is added.
> 
> That attached patch fixes both the above problem and the the one in the
> mode-line.

Thanks, feel free to install.

bug#76014: 31.0.50; Wrong highlighting of "All" in mode-line

[Gerd Möllmann]

Eli Zaretskii <eliz@gnu.org> writes:

> Thanks, feel free to install.

Pushed and closing.