bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Ergus via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Following up the conversation in the develops mailing list I will report
this issue still happening:

In c++-ts-mode, the namespaces are not fontified like in c++-mode

(i.e in std::string the `std` used to have font-lock-constant-face while
`string` used to have font-lock-type-face).

It seems like tresitter identifies them properly like
(namespace_identifier) and (type_identifier), but the fontification rule
is wrong.

There was an attempt to fix it in c6a5aae3da17459be7550c but the issue
is still there.

Best,
Ergus

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

> Date: Sun, 19 May 2024 20:14:19 +0200
> From:  Ergus via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> 
> Following up the conversation in the develops mailing list I will report
> this issue still happening:
> 
> In c++-ts-mode, the namespaces are not fontified like in c++-mode
> 
> (i.e in std::string the `std` used to have font-lock-constant-face while
> `string` used to have font-lock-type-face).

Why do you think std should be in font-lock-constant-face?  The name
of a namespace is not a constant, it's an identifier.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Ergus via Bug reports for GNU Emacs, the Swiss army knife of text editors]

On Sun, May 19, 2024 at 09:36:07PM GMT, Eli Zaretskii wrote:
>> Date: Sun, 19 May 2024 20:14:19 +0200
>> From:  Ergus via "Bug reports for GNU Emacs,
>>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
>>
>>
>> Following up the conversation in the develops mailing list I will report
>> this issue still happening:
>>
>> In c++-ts-mode, the namespaces are not fontified like in c++-mode
>>
>> (i.e in std::string the `std` used to have font-lock-constant-face while
>> `string` used to have font-lock-type-face).
>
>Why do you think std should be in font-lock-constant-face?  The name
>of a namespace is not a constant, it's an identifier.

Hi Eli:

That's how namespaces are fontified in the c++-mode. Not telling it is
correct, wrong or if needs improvement; just that c++-ts-mode is not
doing in the same way.

Try this:

```main.cpp

const std::string a;

class myclass {
	std::time::timespec var;
};

int main()
{
	std::string b = 1;

	
}
```

and then M-x c++-ts-mode you will see the difference.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

> Date: Sun, 19 May 2024 21:00:42 +0200
> From: Ergus <spacibba@aol.com>
> Cc: Yuan Fu <casouri@gmail.com>, 71070@debbugs.gnu.org
> 
> >Why do you think std should be in font-lock-constant-face?  The name
> >of a namespace is not a constant, it's an identifier.
> 
> Hi Eli:
> 
> That's how namespaces are fontified in the c++-mode. Not telling it is
> correct, wrong or if needs improvement; just that c++-ts-mode is not
> doing in the same way.
> 
> Try this:
> 
> ```main.cpp
> 
> const std::string a;
> 
> class myclass {
> 	std::time::timespec var;
> };
> 
> int main()
> {
> 	std::string b = 1;
> 
> 	
> }
> ```
> 
> and then M-x c++-ts-mode you will see the difference.

No one said that what c++-mode does is necessarily correct.  maybe it
is, maybe it isn't.

How do other C++ IDEs fontify namespace names?

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Ergus via Bug reports for GNU Emacs, the Swiss army knife of text editors]

On Sun, May 19, 2024 at 10:13:45PM GMT, Eli Zaretskii wrote:
>> Date: Sun, 19 May 2024 21:00:42 +0200
>> From: Ergus <spacibba@aol.com>
>> Cc: Yuan Fu <casouri@gmail.com>, 71070@debbugs.gnu.org
>>
>> >Why do you think std should be in font-lock-constant-face?  The name
>> >of a namespace is not a constant, it's an identifier.
>>
>> Hi Eli:
>>
>> That's how namespaces are fontified in the c++-mode. Not telling it is
>> correct, wrong or if needs improvement; just that c++-ts-mode is not
>> doing in the same way.
>>
>> Try this:
>>
>> ```main.cpp
>>
>> const std::string a;
>>
>> class myclass {
>> 	std::time::timespec var;
>> };
>>
>> int main()
>> {
>> 	std::string b = 1;
>>
>> 	
>> }
>> ```
>>
>> and then M-x c++-ts-mode you will see the difference.
>
>No one said that what c++-mode does is necessarily correct.  maybe it
>is, maybe it isn't.
>
>How do other C++ IDEs fontify namespace names?

Hi Eli:

Every editor-ide has its own approach for this. But emacs has it own
flavor and the ts-* intention was to keep it as close as possible to the
status-quo; that's why I am reporting it here.

There are many details missing in the c/c++-ts-mode compared to
c-mode... but I understand that some of them are WIP while others are
just too complex to port.

My main concern here is that this seemed like a simple issue considering
that treesitter recognizes the namespace correctly. But the Yuan's fix
didn't work; so maybe there is a detail we are missing here, or that
needs extra documentation? Or in the worst case some detail/issue broken
in the ts api?

Best,
Ergus

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

> Date: Sun, 19 May 2024 23:36:41 +0200
> From: Ergus <spacibba@aol.com>
> Cc: casouri@gmail.com, 71070@debbugs.gnu.org
> 
> On Sun, May 19, 2024 at 10:13:45PM GMT, Eli Zaretskii wrote:
> >No one said that what c++-mode does is necessarily correct.  maybe it
> >is, maybe it isn't.
> >
> >How do other C++ IDEs fontify namespace names?
> 
> Hi Eli:
> 
> Every editor-ide has its own approach for this. But emacs has it own
> flavor and the ts-* intention was to keep it as close as possible to the
> status-quo; that's why I am reporting it here.
> 
> There are many details missing in the c/c++-ts-mode compared to
> c-mode... but I understand that some of them are WIP while others are
> just too complex to port.

I understand all that, but still: can you (or someone else) answer my
question about the accepted practices of IDEs in this matter: do they
highlight the namespace identifiers differently than other
identifiers, or do they use the same highlighting?

It is IMO important to know what are the accepted practices, to deal
with this issue in a proper perspective.

> My main concern here is that this seemed like a simple issue considering
> that treesitter recognizes the namespace correctly. But the Yuan's fix
> didn't work; so maybe there is a detail we are missing here, or that
> needs extra documentation? Or in the worst case some detail/issue broken
> in the ts api?

I don't know.  In particular, I don't know what specific aspects of
this did Yuan try to fix.  Yuan is CC'ed and will hopefully chime in
and answer these questions.  Meanwhile we should make up our minds
regarding the desired behavior, which is mostly independent of what
Yuan tried to do and even of what c++-mode does.

Thanks.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Dmitry Gutov]

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Hi Eli,

On 20/05/2024 14:11, Eli Zaretskii wrote:
>> Every editor-ide has its own approach for this. But emacs has it own
>> flavor and the ts-* intention was to keep it as close as possible to the
>> status-quo; that's why I am reporting it here.
>>
>> There are many details missing in the c/c++-ts-mode compared to
>> c-mode... but I understand that some of them are WIP while others are
>> just too complex to port.
> I understand all that, but still: can you (or someone else) answer my
> question about the accepted practices of IDEs in this matter: do they
> highlight the namespace identifiers differently than other
> identifiers, or do they use the same highlighting?

Does the attached screenshot answer the question? It's from VS Code.

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bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Yuan Fu]

> On May 21, 2024, at 4:27 PM, Dmitry Gutov <dmitry@gutov.dev> wrote:
> 
> Hi Eli,
> 
> On 20/05/2024 14:11, Eli Zaretskii wrote:
>>> Every editor-ide has its own approach for this. But emacs has it own
>>> flavor and the ts-* intention was to keep it as close as possible to the
>>> status-quo; that's why I am reporting it here.
>>> 
>>> There are many details missing in the c/c++-ts-mode compared to
>>> c-mode... but I understand that some of them are WIP while others are
>>> just too complex to port.
>> I understand all that, but still: can you (or someone else) answer my
>> question about the accepted practices of IDEs in this matter: do they
>> highlight the namespace identifiers differently than other
>> identifiers, or do they use the same highlighting?
> 
> Does the attached screenshot answer the question? It's from VS Code.<Screenshot from 2024-05-22 02-24-26.png>

I went ahead and made c++-ts-mode fontify namespaces in constant face. But feel free to revert or change my commit.

(It’d be better if someone can add a new builtin face for namespace and make it inherit from constant face, like what we did for property face, etc.)

Yuan

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

> Date: Wed, 22 May 2024 02:27:08 +0300
> Cc: casouri@gmail.com, 71070@debbugs.gnu.org
> From: Dmitry Gutov <dmitry@gutov.dev>
> 
> > I understand all that, but still: can you (or someone else) answer my
> > question about the accepted practices of IDEs in this matter: do they
> > highlight the namespace identifiers differently than other
> > identifiers, or do they use the same highlighting?
> 
> Does the attached screenshot answer the question? It's from VS Code.

Thanks.  Not sure I get it completely.  It seems like namespace names
are fontified like class names?  They are not fontified like
constants.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Dmitry Gutov]

On 22/05/2024 15:17, Eli Zaretskii wrote:
>> Date: Wed, 22 May 2024 02:27:08 +0300
>> Cc:casouri@gmail.com,71070@debbugs.gnu.org
>> From: Dmitry Gutov<dmitry@gutov.dev>
>>
>>> I understand all that, but still: can you (or someone else) answer my
>>> question about the accepted practices of IDEs in this matter: do they
>>> highlight the namespace identifiers differently than other
>>> identifiers, or do they use the same highlighting?
>> Does the attached screenshot answer the question? It's from VS Code.
> Thanks.  Not sure I get it completely.  It seems like namespace names
> are fontified like class names?  They are not fontified like
> constants.

Seems like it (although some themes might use some additional colors to 
differentiate between these two, the default theme does not).

Perhaps it is done so that the expression foo::class_name reads 
naturally (in one color).

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Yuan Fu]

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> On May 22, 2024, at 6:33 AM, Dmitry Gutov <dmitry@gutov.dev> wrote:
> 
> On 22/05/2024 15:17, Eli Zaretskii wrote:
>>> Date: Wed, 22 May 2024 02:27:08 +0300
>>> Cc:casouri@gmail.com,71070@debbugs.gnu.org
>>> From: Dmitry Gutov<dmitry@gutov.dev>
>>> 
>>>> I understand all that, but still: can you (or someone else) answer my
>>>> question about the accepted practices of IDEs in this matter: do they
>>>> highlight the namespace identifiers differently than other
>>>> identifiers, or do they use the same highlighting?
>>> Does the attached screenshot answer the question? It's from VS Code.
>> Thanks.  Not sure I get it completely.  It seems like namespace names
>> are fontified like class names?  They are not fontified like
>> constants.
> 
> Seems like it (although some themes might use some additional colors to differentiate between these two, the default theme does not).
> 
> Perhaps it is done so that the expression foo::class_name reads naturally (in one color).

Am I missing something? I got the exact opposite conclusion from the screenshot: it seems the effect is that namespaces are colored differently from class names:


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Yuan

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Dmitry Gutov]

On 06/06/2024 08:28, Yuan Fu wrote:
>> Seems like it (although some themes might use some additional colors to differentiate between these two, the default theme does not).
>>
>> Perhaps it is done so that the expression foo::class_name reads naturally (in one color).
> Am I missing something? I got the exact opposite conclusion from the screenshot: it seems the effect is that namespaces are colored differently from class names:

The class names I meant are A and B on my screenshot.

Maybe tree-sitter doesn't see them as class names specifically, just 
non-primitive identifiers in type position.

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

Ping!  Can we please make some progress here?

> Date: Thu, 6 Jun 2024 23:16:18 +0300
> Cc: Eli Zaretskii <eliz@gnu.org>, Ergus <spacibba@aol.com>,
>  71070@debbugs.gnu.org
> From: Dmitry Gutov <dmitry@gutov.dev>
> 
> On 06/06/2024 08:28, Yuan Fu wrote:
> >> Seems like it (although some themes might use some additional colors to differentiate between these two, the default theme does not).
> >>
> >> Perhaps it is done so that the expression foo::class_name reads naturally (in one color).
> > Am I missing something? I got the exact opposite conclusion from the screenshot: it seems the effect is that namespaces are colored differently from class names:
> 
> The class names I meant are A and B on my screenshot.
> 
> Maybe tree-sitter doesn't see them as class names specifically, just 
> non-primitive identifiers in type position.
> 

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Yuan Fu]

> On Jun 15, 2024, at 1:34 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> 
> Ping!  Can we please make some progress here?

As for the original reported bug, I’ve fixed that (now c++-ts-mode fontifies namespaces in constant face). Perhaps namespaces could be fontified in type face instead. I don’t have any opinion on that. My take is that we could add a namespace/module face and make it inherit from either type or constant.

Yuan

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Tue, 18 Jun 2024 23:27:47 -0700
> Cc: Dmitry Gutov <dmitry@gutov.dev>,
>  Ergus <spacibba@aol.com>,
>  71070@debbugs.gnu.org
> 
> 
> 
> > On Jun 15, 2024, at 1:34 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> > 
> > Ping!  Can we please make some progress here?
> 
> As for the original reported bug, I’ve fixed that (now c++-ts-mode fontifies namespaces in constant face). Perhaps namespaces could be fontified in type face instead. I don’t have any opinion on that. My take is that we could add a namespace/module face and make it inherit from either type or constant.

So you are basically saying that this bug should be closed, and if
there are more requests, they should open a new bug report?

bug#71070: 30.0.50; c++-ts-mode namespace wrong fontification.

[Yuan Fu]

> On Jun 19, 2024, at 4:52 AM, Eli Zaretskii <eliz@gnu.org> wrote:
> 
>> From: Yuan Fu <casouri@gmail.com>
>> Date: Tue, 18 Jun 2024 23:27:47 -0700
>> Cc: Dmitry Gutov <dmitry@gutov.dev>,
>> Ergus <spacibba@aol.com>,
>> 71070@debbugs.gnu.org
>> 
>> 
>> 
>>> On Jun 15, 2024, at 1:34 AM, Eli Zaretskii <eliz@gnu.org> wrote:
>>> 
>>> Ping!  Can we please make some progress here?
>> 
>> As for the original reported bug, I’ve fixed that (now c++-ts-mode fontifies namespaces in constant face). Perhaps namespaces could be fontified in type face instead. I don’t have any opinion on that. My take is that we could add a namespace/module face and make it inherit from either type or constant.
> 
> So you are basically saying that this bug should be closed, and if
> there are more requests, they should open a new bug report?

Yes, this bug is resolved. Closing the report.

Yuan