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

[Ergus]

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