bug#71430: Persistent Highlighting Issue with query-replace using "act-and-show" Option

bug#71430: Persistent Highlighting Issue with query-replace using "act-and-show" Option

[Gabriele Nicolardi]

[-- Attachment #1.1: Type: text/plain, Size: 1557 bytes --]

Hi,
I’ve encountered a potential bug in Emacs when using the |query-replace| 
(via |perform-replace|) functions. When performing text replacements 
across a buffer and choosing to replace but not immediately move the 
point (using the |,| |act-and-show| option), the function does replace 
the text as expected but fails to update the highlighting to the region 
containing the replacement.

*Steps to Reproduce:*

 1.

    Open a buffer with the following content:

    |String to be replaced. Another string. String to be replaced.
    Another string. End |

 2.

    Run the following command:

    |(query-replace "String to be replaced." "Replacement." nil
    (point-min) (point-max)) |

 3.

    When prompted to replace a match, use the |,| (|act-and-show|)
    option to replace the text but pause moving to the next match.

*Expected Behavior:*
After a replacement is made and before moving to the next match, the 
highlighted region of the replaced text should be “updated” to fit the 
replaced text.

*Actual Behavior:*
The highlighting remains on the matched region. This issue can be 
visually confirmed in the following animation:
View Animation on Imgur <https://imgur.com/a/BxVwVff>

*Visual Evidence:*

  * Highlight *before* using |act-and-show| (match):

  * Highlight *after* using |act-and-show| while paused (replacement):

As demonstrated, the highlighted region post-replacement does not 
correspond to any current match, which is misleading and might affect 
further editing decisions.

Best regards,

Gabriele Nicolardi

​

[-- Attachment #1.2.1: Type: text/html, Size: 146549 bytes --]

[-- Attachment #1.2.2: MWE_130.png --]
[-- Type: image/png, Size: 38561 bytes --]

[-- Attachment #1.2.3: MWE_131.png --]
[-- Type: image/png, Size: 37614 bytes --]

[-- Attachment #2: match.png --]
[-- Type: image/png, Size: 38561 bytes --]

[-- Attachment #3: replacement.png --]
[-- Type: image/png, Size: 37614 bytes --]

bug#71430: Persistent Highlighting Issue with query-replace using "act-and-show" Option

[Eli Zaretskii]

> Date: Sat, 8 Jun 2024 09:29:41 +0200
> From: Gabriele Nicolardi <gabriele@medialab.sissa.it>
> 
> I’ve encountered a potential bug in Emacs when using the |query-replace| 
> (via |perform-replace|) functions. When performing text replacements 
> across a buffer and choosing to replace but not immediately move the 
> point (using the |,| |act-and-show| option), the function does replace 
> the text as expected but fails to update the highlighting to the region 
> containing the replacement.
> 
> *Steps to Reproduce:*
> 
>  1.
> 
>     Open a buffer with the following content:
> 
>     |String to be replaced. Another string. String to be replaced.
>     Another string. End |
> 
>  2.
> 
>     Run the following command:
> 
>     |(query-replace "String to be replaced." "Replacement." nil
>     (point-min) (point-max)) |
> 
>  3.
> 
>     When prompted to replace a match, use the |,| (|act-and-show|)
>     option to replace the text but pause moving to the next match.
> 
> *Expected Behavior:*
> After a replacement is made and before moving to the next match, the 
> highlighted region of the replaced text should be “updated” to fit the 
> replaced text.
> 
> *Actual Behavior:*
> The highlighting remains on the matched region. This issue can be 
> visually confirmed in the following animation:

You don't say in what version of Emacs you see the problematic
behavior.  I can reproduce the behavior you report in Emacs 29, but
not in Emacs 30 (on the master branch of the Emacs Git repository).
So I think this bug was already solved on the master branch, which
will become Emacs 30.

bug#71430: Persistent Highlighting Issue with query-replace using "act-and-show" Option

[Eli Zaretskii]

> Date: Sat, 8 Jun 2024 11:05:24 +0200
> From: Gabriele Nicolardi <gabriele@medialab.sissa.it>
> 
> Il 08/06/24 10:33, Eli Zaretskii ha scritto:
> >> Date: Sat, 8 Jun 2024 09:29:41 +0200
> >> From: Gabriele Nicolardi <gabriele@medialab.sissa.it>
> >>
> >> I’ve encountered a potential bug in Emacs when using the |query-replace|
> >> (via |perform-replace|) functions. When performing text replacements
> >> across a buffer and choosing to replace but not immediately move the
> >> point (using the |,| |act-and-show| option), the function does replace
> >> the text as expected but fails to update the highlighting to the region
> >> containing the replacement.
> >>
> >> *Steps to Reproduce:*
> >>
> >>   1.
> >>
> >>      Open a buffer with the following content:
> >>
> >>      |String to be replaced. Another string. String to be replaced.
> >>      Another string. End |
> >>
> >>   2.
> >>
> >>      Run the following command:
> >>
> >>      |(query-replace "String to be replaced." "Replacement." nil
> >>      (point-min) (point-max)) |
> >>
> >>   3.
> >>
> >>      When prompted to replace a match, use the |,| (|act-and-show|)
> >>      option to replace the text but pause moving to the next match.
> >>
> >> *Expected Behavior:*
> >> After a replacement is made and before moving to the next match, the
> >> highlighted region of the replaced text should be “updated” to fit the
> >> replaced text.
> >>
> >> *Actual Behavior:*
> >> The highlighting remains on the matched region. This issue can be
> >> visually confirmed in the following animation:
> > You don't say in what version of Emacs you see the problematic
> > behavior.  I can reproduce the behavior you report in Emacs 29, but
> > not in Emacs 30 (on the master branch of the Emacs Git repository).
> > So I think this bug was already solved on the master branch, which
> > will become Emacs 30.
> 
> 
> 
> > > Cc: 71430@debbugs.gnu.org
> > > Date: Sat, 08 Jun 2024 11:33:55 +0300
> > > From: Eli Zaretskii <eliz@gnu.org>
> > > 
> > > > Date: Sat, 8 Jun 2024 09:29:41 +0200
> > > > From: Gabriele Nicolardi <gabriele@medialab.sissa.it>
> > > > 
> > > > I’ve encountered a potential bug in Emacs when using the |query-replace| 
> > > > (via |perform-replace|) functions. When performing text replacements 
> > > > across a buffer and choosing to replace but not immediately move the 
> > > > point (using the |,| |act-and-show| option), the function does replace 
> > > > the text as expected but fails to update the highlighting to the region 
> > > > containing the replacement.
> > > > 
> > > > *Steps to Reproduce:*
> > > > 
> > > >  1.
> > > > 
> > > >     Open a buffer with the following content:
> > > > 
> > > >     |String to be replaced. Another string. String to be replaced.
> > > >     Another string. End |
> > > > 
> > > >  2.
> > > > 
> > > >     Run the following command:
> > > > 
> > > >     |(query-replace "String to be replaced." "Replacement." nil
> > > >     (point-min) (point-max)) |
> > > > 
> > > >  3.
> > > > 
> > > >     When prompted to replace a match, use the |,| (|act-and-show|)
> > > >     option to replace the text but pause moving to the next match.
> > > > 
> > > > *Expected Behavior:*
> > > > After a replacement is made and before moving to the next match, the 
> > > > highlighted region of the replaced text should be “updated” to fit the 
> > > > replaced text.
> > > > 
> > > > *Actual Behavior:*
> > > > The highlighting remains on the matched region. This issue can be 
> > > > visually confirmed in the following animation:
> > > 
> > > You don't say in what version of Emacs you see the problematic
> > > behavior.  I can reproduce the behavior you report in Emacs 29, but
> > > not in Emacs 30 (on the master branch of the Emacs Git repository).
> > > So I think this bug was already solved on the master branch, which
> > > will become Emacs 30.
> 
> Oh, sorry! My Emacs version is 29.3.

OK, thanks, so I'm now closing this bug.