bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

[Platon Pronko]

In cc-mode (C lang files) calling backward-kill-word seems to be too eager. For example, given the following file and cursor position:

```
int main() {
   printf("alpha beta gamma<cursor>
}
```

calling backward-kill-word results in

```
int main() {
   <cursor>
}
```

while the expected result is probably:

```
int main() {
   printf("alpha beta <cursor>
}
```

It seems that this is a regression in commit dae8aab52874441a70a94435d50f25b27301d9b0, by Alan Mackenzie on 2023-06-21.

In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
  3.24.39, cairo version 1.18.0) of 2023-12-29 built on the-big-maker
Repository revision: ea3d211f3f7ecc5b59d5affc1aed812a2ded62b0
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101010
System Description: Arch Linux

Configured using:
  'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
  --localstatedir=/var --mandir=/usr/share/man --with-gameuser=:games
  --with-modules --without-m17n-flt --without-gconf
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  --without-xaw3d --with-sound=no --with-tree-sitter --without-gpm
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  '--program-transform-name=s/\([ec]tags\)/\1.emacs/'
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Configured features:
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Major mode: C/*l

Minor modes in effect:
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Load-path shadows:
/home/platon/.emacs.d/elpa/lispy-20230314.1738/elpa hides /home/platon/.emacs.d/elpa/ivy-20231025.2311/elpa
/home/platon/.emacs.d/elpa/transient-20231216.1908/transient hides /usr/share/emacs/30.0.50/lisp/transient
/home/platon/.emacs.d/elpa/less-css-mode-20161001.453/less-css-mode hides /usr/share/emacs/30.0.50/lisp/textmodes/less-css-mode

Features:
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Memory information:
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bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

[Eli Zaretskii]

> Date: Fri, 29 Dec 2023 21:23:54 +0500
> From: Platon Pronko <platon7pronko@gmail.com>
> 
> In cc-mode (C lang files) calling backward-kill-word seems to be too eager. For example, given the following file and cursor position:
> 
> ```
> int main() {
>    printf("alpha beta gamma<cursor>
> }
> ```
> 
> calling backward-kill-word results in
> 
> ```
> int main() {
>    <cursor>
> }
> ```
> 
> while the expected result is probably:
> 
> ```
> int main() {
>    printf("alpha beta <cursor>
> }
> ```
> 
> It seems that this is a regression in commit dae8aab52874441a70a94435d50f25b27301d9b0, by Alan Mackenzie on 2023-06-21.

Adding Alan to the discussion.

bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

[Alan Mackenzie]

Hello, Platon.

Thanks for taking the trouble to report this bug, and sorry for the
annoyance it must have caused.

On Fri, Dec 29, 2023 at 21:23:54 +0500, Platon Pronko wrote:
> In cc-mode (C lang files) calling backward-kill-word seems to be too
> eager. For example, given the following file and cursor position:

> ```
> int main() {
>    printf("alpha beta gamma<cursor>
> }
> ```

> calling backward-kill-word results in

> ```
> int main() {
>    <cursor>
> }
> ```

> while the expected result is probably:

> ```
> int main() {
>    printf("alpha beta <cursor>
> }
> ```

> It seems that this is a regression in commit
> dae8aab52874441a70a94435d50f25b27301d9b0, by Alan Mackenzie on
> 2023-06-21.

Indeed, yes.  Thanks for doing the bisection, it saved me a lot of work.

I've committed a fix for the bug to the master branch of the repository.
Would you please update your copy of Emacs, test the fix, then either
confirm the fix is complete, or say what is still not working.  Then we
can close the bug.

Happy New Year!

> In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
>   3.24.39, cairo version 1.18.0) of 2023-12-29 built on the-big-maker
> Repository revision: ea3d211f3f7ecc5b59d5affc1aed812a2ded62b0
> Repository branch: master
> Windowing system distributor 'The X.Org Foundation', version 11.0.12101010
> System Description: Arch Linux

[ .... ]

-- 
Alan Mackenzie (Nuremberg, Germany).

bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

[Platon Pronko]

On 2023-12-31 16:15, Alan Mackenzie wrote:
> I've committed a fix for the bug to the master branch of the repository.
> Would you please update your copy of Emacs, test the fix, then either
> confirm the fix is complete, or say what is still not working.  Then we
> can close the bug.
> 
> Happy New Year!
> 

Thank you! I've tested the fix, it works for me.

-- 
Best regards,
Platon Pronko
PGP 2A62D77A7A2CB94E

bug#68111: 30.0.50; backward-kill-word too eager in cc-mode

[Alan Mackenzie]

Hello, Platon.

On Wed, Jan 03, 2024 at 20:15:46 +0500, Platon Pronko wrote:
> On 2023-12-31 16:15, Alan Mackenzie wrote:
> > I've committed a fix for the bug to the master branch of the repository.
> > Would you please update your copy of Emacs, test the fix, then either
> > confirm the fix is complete, or say what is still not working.  Then we
> > can close the bug.

> > Happy New Year!


> Thank you! I've tested the fix, it works for me.

Thanks for the testing.  I'm closing the bug with this post.

> -- 
> Best regards,
> Platon Pronko
> PGP 2A62D77A7A2CB94E

-- 
Alan Mackenzie (Nuremberg, Germany).