GNU bug report logs - #78492
[PATCH] 31.0.50; eglot.el does not support pyrefly LSP server (python)

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
To: bug-gnu-emacs <at> gnu.org
Subject: [PATCH] 31.0.50; eglot.el does not support pyrefly LSP server (python)
Date: Mon, 19 May 2025 10:04:18 +0200

[Message part 1 (text/plain, inline)]

Hey everyone.

There's a new, fast combined type-checker and LSP-server available for Python called "pyrefly". The source can be found here:
https://github.com/facebook/pyrefly

Currently it's not possible to use this LSP-server with eglot, due to missing configuration.

Attached is a patch which fixes this.

--
Kind regards
Jostein





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[Message part 2 (text/html, inline)]

[0001-eglot.el-Add-supprt-for-Pyrefly-LSP-for-Python.patch (application/octet-stream, attachment)]

[Message part 4 (text/html, inline)]

Message #8 received at 78492 <at> debbugs.gnu.org (full text, mbox):

From: Ship Mints <shipmints <at> gmail.com>
To: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
Cc: 78492 <at> debbugs.gnu.org
Subject: Re: bug#78492: [PATCH] 31.0.50; eglot.el does not support pyrefly LSP
 server (python)
Date: Mon, 19 May 2025 06:37:28 -0400

[Message part 1 (text/plain, inline)]

On Mon, May 19, 2025 at 4:06 AM Jostein Kjønigsen <
jostein <at> secure.kjonigsen.net> wrote:

> Hey everyone.
>
> There's a new, fast combined type-checker and LSP-server available for
> Python called "pyrefly". The source can be found here:
> https://github.com/facebook/pyrefly
>
> Currently it's not possible to use this LSP-server with eglot, due to
> missing configuration.
>
> Attached is a patch which fixes this.
>

Cool.  You jumped on pyrefly fast.  As eglot supports only one LSP server
at a time per session (for now...I think Joao has a multiplexer idea), it
might also be good to see pyrefly integrated into pylsp as mypy is (see
https://github.com/python-lsp/pylsp-mypy).  This way, eglot users can
benefit from simultaneous linting, type checking, and code navigation vs.
just type checking alone which is what they'd get using pyrefly as an LSP.
To be clear, I'm not saying skip the patch, I'm saying let's also encourage
integration under a multiplexing LSP.

[Message part 2 (text/html, inline)]

Message #11 received at 78492 <at> debbugs.gnu.org (full text, mbox):

From: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
To: Ship Mints <shipmints <at> gmail.com>
Cc: 78492 <at> debbugs.gnu.org
Subject: Re: bug#78492: [PATCH] 31.0.50; eglot.el does not support pyrefly LSP
 server (python)
Date: Mon, 19 May 2025 12:50:40 +0200

[Message part 1 (text/plain, inline)]

> On 19 May 2025, at 12:37, Ship Mints <shipmints <at> gmail.com> wrote:
> 
> Cool.  You jumped on pyrefly fast.  As eglot supports only one LSP server at a time per session (for now...I think Joao has a multiplexer idea), it might also be good to see pyrefly integrated into pylsp as mypy is (see https://github.com/python-lsp/pylsp-mypy).  This way, eglot users can benefit from simultaneous linting, type checking, and code navigation vs. just type checking alone which is what they'd get using pyrefly as an LSP.  To be clear, I'm not saying skip the patch, I'm saying let's also encourage integration under a multiplexing LSP.

Hey!

Thanks for the quick reply.

I have to admit I didn't know about that whole pylsp-extensibility-and-multiplexing story. It sounds useful, but I don't feel like that's something I'm going to be taking charge of.

If someone builds it, I'm sure I'll try it out though ;)

--
Jostein

[Message part 2 (text/html, inline)]

Message #14 received at 78492 <at> debbugs.gnu.org (full text, mbox):

From: Ship Mints <shipmints <at> gmail.com>
To: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
Cc: 78492 <at> debbugs.gnu.org
Subject: Re: bug#78492: [PATCH] 31.0.50; eglot.el does not support pyrefly LSP
 server (python)
Date: Mon, 19 May 2025 06:53:53 -0400

[Message part 1 (text/plain, inline)]

On Mon, May 19, 2025 at 6:50 AM Jostein Kjønigsen <
jostein <at> secure.kjonigsen.net> wrote:

>
> On 19 May 2025, at 12:37, Ship Mints <shipmints <at> gmail.com> wrote:
>
> Cool.  You jumped on pyrefly fast.  As eglot supports only one LSP server
> at a time per session (for now...I think Joao has a multiplexer idea), it
> might also be good to see pyrefly integrated into pylsp as mypy is (see
> https://github.com/python-lsp/pylsp-mypy).  This way, eglot users can
> benefit from simultaneous linting, type checking, and code navigation vs.
> just type checking alone which is what they'd get using pyrefly as an LSP.
> To be clear, I'm not saying skip the patch, I'm saying let's also encourage
> integration under a multiplexing LSP.
>
>
> Hey!
>
> Thanks for the quick reply.
>
> I have to admit I didn't know about that whole
> pylsp-extensibility-and-multiplexing story. It sounds useful, but I don't
> feel like that's something I'm going to be taking charge of.
>

I suggested encouraging not volunteering but of course you could do both!
How about at least submitting an issue for the feature request here
https://github.com/python-lsp/python-lsp-server/issues

[Message part 2 (text/html, inline)]

Message #17 received at 78492 <at> debbugs.gnu.org (full text, mbox):

From: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
To: Ship Mints <shipmints <at> gmail.com>
Cc: 78492 <at> debbugs.gnu.org
Subject: Re: bug#78492: [PATCH] 31.0.50; eglot.el does not support pyrefly LSP
 server (python)
Date: Mon, 19 May 2025 13:17:31 +0200

[Message part 1 (text/plain, inline)]

> On 19 May 2025, at 12:53, Ship Mints <shipmints <at> gmail.com> wrote:
> 
> On Mon, May 19, 2025 at 6:50 AM Jostein Kjønigsen <jostein <at> secure.kjonigsen.net <mailto:jostein <at> secure.kjonigsen.net>> wrote:
>> 
>>> On 19 May 2025, at 12:37, Ship Mints <shipmints <at> gmail.com <mailto:shipmints <at> gmail.com>> wrote:
>>> 
>>> Cool.  You jumped on pyrefly fast.  As eglot supports only one LSP server at a time per session (for now...I think Joao has a multiplexer idea), it might also be good to see pyrefly integrated into pylsp as mypy is (see https://github.com/python-lsp/pylsp-mypy).  This way, eglot users can benefit from simultaneous linting, type checking, and code navigation vs. just type checking alone which is what they'd get using pyrefly as an LSP.  To be clear, I'm not saying skip the patch, I'm saying let's also encourage integration under a multiplexing LSP.
>> 
>> Hey!
>> 
>> Thanks for the quick reply.
>> 
>> I have to admit I didn't know about that whole pylsp-extensibility-and-multiplexing story. It sounds useful, but I don't feel like that's something I'm going to be taking charge of.
> 
> I suggested encouraging not volunteering but of course you could do both!  How about at least submitting an issue for the feature request here https://github.com/python-lsp/python-lsp-server/issues
> 


Created an issue. It can be found here:
https://github.com/python-lsp/python-lsp-server/issues/648

Now... Back to actual code in actual Emacs, and my patch specifically. Who can review it, test it and get it merged? ;)

--
Jostein

[Message part 2 (text/html, inline)]

Message #22 received at 78492-done <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
Cc: 78492-done <at> debbugs.gnu.org
Subject: Re: bug#78492: [PATCH] 31.0.50;
 eglot.el does not support pyrefly LSP server (python)
Date: Mon, 19 May 2025 14:56:13 +0300

> From: Jostein Kjønigsen <jostein <at> secure.kjonigsen.net>
> Date: Mon, 19 May 2025 10:04:18 +0200
> 
> Hey everyone.
> 
> There's a new, fast combined type-checker and LSP-server available for Python called "pyrefly". The source can be found here:
> https://github.com/facebook/pyrefly
> 
> Currently it's not possible to use this LSP-server with eglot, due to missing configuration.
> 
> Attached is a patch which fixes this.

Thanks, installed on the emacs-30 branch (will be merged to master in
a couple of days), and closing the bug.

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