bug#4096: 23.1.50; forward-char sometimes steps over overlay 'display

bug#4096: 23.1.50; forward-char sometimes steps over overlay 'display

[Lennart Borgman]

I have two rather similar 'display strings for two invisible
overlays. In one case forward-char steps over the 'display string part
and in the other it stops on it (as it should).

For the case when it steps over the display string looks something like

#("+ <p>...(6 hidden lines)" 0 1
  (face mode-line)
  2 3
  (fontified t)
  3 4
  (face font-lock-function-name-face fontified t)
  4 5
  (fontified t))

and for the case where it stops (expected behaviour) it looks like

#("+...(155 hidden lines)" 0 1
  (face mode-line))

I can reproduce it, but have not made a test case. However the behaviour
can easily be seen in the devel sources for nXhtml. One case is for
outline-minor-mode and one is for hs-minor-mode used in a nxhtml-mode buffer.


In GNU Emacs 23.1.50.1 (i386-mingw-nt5.1.2600)
 of 2009-08-01
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4) --no-opt --cflags
-Ic:/g/include -fno-crossjumping'

bug#4096: 23.1.50; forward-char sometimes steps over overlay 'display

[Lennart Borgman]

(Please merge this with 4094.)

I think the problem might be in

    adjust_for_invis_intang

or the use of it. This function checks for insertion type.

This is different for the overlays I have mentioned here. One is
created by outline-minor-mode and one by hs-minor-mode. One of them
set insertion type for the beginning of the overlay, the other does
not. In one of the cases at least forward-char works, in the other it
does not. (backward-char still does not work.)

However it must be a mistake to check for insertion type here. Forward
char has nothing to do with that. (Note: adjust_for_invis_intang is
called by set_point_both.)

bug#4096: 23.1.50; forward-char sometimes steps over overlay 'display

[Stefan Monnier]

> I think the problem might be in

>     adjust_for_invis_intang

> or the use of it. This function checks for insertion type.

This function should not do anything if you don't have `intangible'
things around.  Do you?  If you do, I'm tempted to say "there's your
problem".


        Stefan

bug#4096: 23.1.50; forward-char sometimes steps over overlay 'display

[Lennart Borgman]

On Mon, Aug 10, 2009 at 6:13 AM, Stefan Monnier<monnier@iro.umontreal.ca> wrote:
>> I think the problem might be in
>
>>     adjust_for_invis_intang
>
>> or the use of it. This function checks for insertion type.
>
> This function should not do anything if you don't have `intangible'
> things around.  Do you?  If you do, I'm tempted to say "there's your
> problem".

Not that I know of. I looked for it but could not find it. (I have not
checked that adjust_for_invis_intang is actually called. I looked
around in the code searching for some reasonable explanation.)

The overlays are created by outline-minor-mode and hs-minor-mode +
'display property added by me.

bug#4094: 23.1.50; posn-at-point gets upset by overlays with 'invisible and 'display

[Chong Yidong]

> posn-at-point reports bad (X . Y) when on a 'displa part of an invisible
> overlay.
>
> This makes line-move-visual behave strange. (A workaround for this could
> be to step back one char in line-move-visual, but this is of course not
> the correct fix.)

Please provide a precise, step-by-step recipe to reproduce this,
starting with `emacs -Q'.

bug#4094: 23.1.50; posn-at-point gets upset by overlays with 'invisible and 'display

[Glenn Morris]

Closed due to lack of response.

Chong Yidong wrote:

> Please provide a precise, step-by-step recipe to reproduce this,
> starting with `emacs -Q'.

bug#4096: closed (Re: bug#4094: 23.1.50; posn-at-point gets upset by overlays with 'invisible and 'display)

[Lennart Borgman]

Sorry, I do not have time to give a precise recipe.

On Sun, Jul 10, 2011 at 02:31, GNU bug Tracking System
<help-debbugs@gnu.org> wrote:
> Your bug report
>
> #4094: 23.1.50; forward-char sometimes steps over overlay 'display
>
> which was filed against the emacs package, has been closed.
>
> The explanation is attached below, along with your original report.
> If you require more details, please reply to 4096@debbugs.gnu.org.
>
> --
> 4094: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=4094
> GNU Bug Tracking System
> Contact help-debbugs@gnu.org with problems
>
>
> ---------- Forwarded message ----------
> From: Glenn Morris <rgm@gnu.org>
> To: 4094-done@debbugs.gnu.org
> Date: Sat, 09 Jul 2011 20:30:08 -0400
> Subject: Re: bug#4094: 23.1.50; posn-at-point gets upset by overlays with 'invisible and 'display
>
> Closed due to lack of response.
>
> Chong Yidong wrote:
>
>> Please provide a precise, step-by-step recipe to reproduce this,
>> starting with `emacs -Q'.
>
>
>
> ---------- Forwarded message ----------
> From: Lennart Borgman <lennart.borgman@gmail.com>
> To: emacs-pretest-bug@gnu.org
> Date: Sun, 9 Aug 2009 18:08:39 +0200
> Subject: 23.1.50; forward-char sometimes steps over overlay 'display
> I have two rather similar 'display strings for two invisible
> overlays. In one case forward-char steps over the 'display string part
> and in the other it stops on it (as it should).
>
> For the case when it steps over the display string looks something like
>
> #("+ <p>...(6 hidden lines)" 0 1
>  (face mode-line)
>  2 3
>  (fontified t)
>  3 4
>  (face font-lock-function-name-face fontified t)
>  4 5
>  (fontified t))
>
> and for the case where it stops (expected behaviour) it looks like
>
> #("+...(155 hidden lines)" 0 1
>  (face mode-line))
>
> I can reproduce it, but have not made a test case. However the behaviour
> can easily be seen in the devel sources for nXhtml. One case is for
> outline-minor-mode and one is for hs-minor-mode used in a nxhtml-mode buffer.
>
>
> In GNU Emacs 23.1.50.1 (i386-mingw-nt5.1.2600)
>  of 2009-08-01
> Windowing system distributor `Microsoft Corp.', version 5.1.2600
> configured using `configure --with-gcc (3.4) --no-opt --cflags
> -Ic:/g/include -fno-crossjumping'
>
>
>