Improve eglot-signature-eldoc-function: More Helpful Documentation!

[mekeor]

Hello. I wrote a custom function for eldoc-documentation-functions, meant as a replacement for eglot-signature-eldoc-function. As far as I understand, the chances that Eglot shows any signature-documentation at all, are very very small, unfortunately. I think we should improve that.

The screenshots show: The original function often just lists loads of type signatures. The customized function shows the type signature and documentation for the currently active "signature".

Here is the code I use:

(defun /eglot-signature-information (cb)
  (when (eglot--server-capable :signatureHelpProvider)
    (let ((buf (current-buffer)))
      (jsonrpc-async-request
        (eglot--current-server-or-lose)
        :textDocument/signatureHelp
        (eglot--TextDocumentPositionParams)
        :success-fn
        (eglot--lambda
          ((SignatureHelp)
            signatures activeSignature activeParameter)
          (let
            ((targetSignatures
               (if activeSignature
                 (list (seq-elt signatures activeSignature))
                 signatures)))
            (eglot--when-buffer-window buf
              (funcall cb
                (unless (seq-empty-p targetSignatures)
                  (string-join
                    (seq-mapcat
                      (eglot--lambda
                        ((SignatureInformation)
                          label documentation
                          parameters activeParameter)
                        (unless (null documentation)
                          (list label
                            (eglot--format-markup documentation))))
                      targetSignatures)
                    "\n\n"))))))
        :deferred :textDocument/signatureHelp))
    t))

(defun /eldoc-add-signature-information ()
  (setq eldoc-documentation-strategy
    #'eldoc-documentation-compose)
  (setq-local eldoc-documentation-functions
    (list
      #'/eglot-signature-information
      #'eglot-hover-eldoc-function)))

(add-hook 'eglot-managed-mode-hook #'/eldoc-add-signature-information)

PS: Sorry for not capturing the cursor in the second screenshot. Just imagine it. It's there, but it's blinking.

[joaotavora]

Hi @mekeor, i did changes to this very recently. If you can, look at the version of Eglot in Emacs master as of today and tell me what you think. I think we had the same idea, more or less.

[joaotavora]

OK, I see it let's follow up there.

[joaotavora]

Oh, please don't send back-to-back emails to [email protected]. That just makes the bug tracker create more bugs. Wait for the confirmation of the bug tracker. You've sent two mails already, wait a bit until the moderators approve them.

[mekeor]

Oh nooo. Damnit!

[mekeor]

Hmm, I don't see any accidentally created bug reports when I search my name in Emacs' bug tracker:

https://debbugs.gnu.org/cgi/pkgreport.cgi?package=emacs;include=originator%3Amekeor

All my e-mails are in one single bug thread.

[mekeor]

On the bug-gnu-emacs mailing-list, my e-mails also appear in one single thread: https://lists.gnu.org/archive/html/bug-gnu-emacs/2023-04/msg00269.html

[mekeor]

On April 4, 2023 11:45:18 AM GMT+02:00, "João Távora" ***@***.***> wrote: I did this two days ago, but I don't know what you are talking about, so ping me in the context of whatever bug this is related to, if you think I can be of help.

Nevermind! Eli had claimed that the bug that I'm experiencing, has been resolved on emacs-29, but apparently the bug on the master-branch is different and still outstanding. So, you can't help me right now. https://debbugs.gnu.org/cgi/bugreport.cgi?bug=62596#15

In that case, you have experienced the "new features of ElDoc" already :-) , and if nothing broke, then that's what's supposed to happen. Just one of these features is user-visible, and quite discreet: the separating line in the `*eldoc*` buffer has been changed and can be customized with `eldoc-buffer-separator` or something like that.

Alright then. I'll give some feedback soon.

[joaotavora]

Let's hope you haven't created 3 bug reports. Maybe the tracker is smart. But if you have, it's no tragedy, just give the moderators some time. João

…

On Thu, Apr 6, 2023, 21:52 mekeor ***@***.***> wrote: On the bug-gnu-emacs mailing-list, my e-mails also appear in one single thread: https://lists.gnu.org/archive/html/bug-gnu-emacs/2023-04/msg00269.html — Reply to this email directly, view it on GitHub <#1200 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAC6PQZQFJ4DYYCSTDUG5EDW74UKTANCNFSM6AAAAAAWQ6AXTA> . You are receiving this because you modified the open/close state.Message ID: ***@***.***>

[mekeor]

Quoting debbugs.gnu.org:

To reply to an existing report, for example #123, send mail to [email protected]. Or to the project's bug mailing list address (e.g. bug-gnu-emacs), but be sure to keep "bug#123" in the subject, else you will create a new report.

So, no need to worry.