emacs configuration?

[anarcat]

First, this looks like a fantastic project, really impressive!

Has anyone managed to make this work in Emacs?

I have first tried to setup something in lsp-mode but couldn't figure out how to add a custom language server, so i switched to eglot (which is something i've been meaning to do for a while anyway), with the following configuration:

(use-package eglot
  :defer
  :hook
  (python-mode . eglot-ensure)
  (markdown-mode . eglot-ensure)
  :bind (:map
         eglot-mode-map
         ("C-c e r" . eglot-rename)
         ("C-c e a" . eglot-code-actions)
         ("C-c e o" . eglot-code-action-organize-imports)
         ("C-c e d" . eldoc)
         ("C-c e f" . eglot-format)
         ("C-c e =" . eglot-format))
  :config
  (add-to-list 'eglot-server-programs
               '(markdown-mode . ("harper-ls")))
  :custom
  (eglot-autoshutdown t) ;; default is to leave servers runing when last buffer exits
  ;; (eglot-events-buffer-size 0)
  ;; (eglot-stay-out-of '(yasnippet))
  (eglot-extend-to-xref nil)) ;; cover files found through xref (M-.)

i think it works in python mode: when i switch to a python buffer for the first time, it takes a while to load (a annoying but good sign) and eventually pops a buffer with [eglot:$dirname] in the modeline. xref works, at least.

but in markdown mode, the server doesn't seem to start at all. this is the diagnostic buffer in emacs:

clipboard.txt

and in *Messages*:

[jsonrpc] Server exited with status 9
Error running timer: (error "[eglot] Timed out after 30 seconds")

I installed harper through the nix-bin package manager installed on a Debian bookworm system, which could cause some problems, I admit, but i'm wondering if anyone else made this work here...

[sbromberger]

I don't know anything about emacs, but it doesn't look like you're calling harper-ls with the --stdio flag. I got timeouts when I didn't do that in my editor (helix).

[anarcat]

that was it, thanks!!! the updated, working, configuration is:

(use-package eglot
  :defer
  :hook
  (python-mode . eglot-ensure)
  (markdown-mode . eglot-ensure)
  :bind (:map
         eglot-mode-map
         ("C-c e r" . eglot-rename)
         ("C-c e a" . eglot-code-actions)
         ("C-c e o" . eglot-code-action-organize-imports)
         ("C-c e d" . eldoc)
         ("C-c e f" . eglot-format)
         ("C-c e =" . eglot-format))
  :config
  (add-to-list 'eglot-server-programs
               '(markdown-mode . ("harper-ls" "--stdio")))
  :custom
  (eglot-autoshutdown t) ;; default is to leave servers runing when last buffer exits
  (eglot-extend-to-xref nil)) ;; cover files found through xref (M-.)

[elijah-potter]

This is fantastic. I'm considering setting up a Wiki page for miscellaneous configurations that people can copy/paste from. Would it be alright if I included yours?

[anarcat]

of course! i would suggest reducing it to a more bare minimum, however, something like this:

(use-package eglot
  :hook
  (text-mode . eglot-ensure)
  :config
  (add-to-list 'eglot-server-programs
               '(text-mode . ("harper-ls" "--stdio"))))

everything else is kind of specific to my setup (e.g. python, keybindings, the xref bit), optimizations (:defer) or optimizations (autoshutdown)... it's not even my full config right now, which is currently:

(use-package eglot
  :defer
  :hook
  (python-mode . eglot-ensure)
  (text-mode . eglot-ensure)
  :bind (:map
         eglot-mode-map
         ("C-c e r" . eglot-rename)
         ("C-c e a" . eglot-code-actions)
         ("C-c e o" . eglot-code-action-organize-imports)
         ("C-c e d" . eldoc)
         ("C-c e f" . eglot-format)
         ("C-c e =" . eglot-format))
  :config
  (add-to-list 'eglot-server-programs
               '(text-mode . ("harper-ls" "--stdio")))
  :custom
  (eglot-autoshutdown t) ;; default is to leave servers runing when last buffer exits
  (eglot-events-buffer-size 0) ;; disable events recording to speed
                               ;; things up, comment out to
                               ;; troubleshoot and look for the EGLOT
                               ;; buffer (eglot-stay-out-of
                               ;; '(yasnippet))
  (eglot-extend-to-xref nil)) ;; cover files found through xref (M-.)

that will eventually make it to https://gitlab.com/anarcat/emacs-d/-/blob/main/init.el once i find time to commit, if you want to cross-reference to a canonical copy.

oh, and also note that i use the use-package package (if that's readable at all), which is not necessarily the way everyone configures such thing. a more canonical way is documented in the eglot docs which would probably be something like:

(with-eval-after-load 'eglot
  (add-hook 'text-mode #'eglot-ensure)
  (add-to-list 'eglot-server-programs
               '(text-mode . ("harper-ls" "--stdio"))))

... but i haven't tested that blob so i'm not sure it works... it should be roughly equivalent though.

[anarcat]

  (eglot-autoshutdown t) ;; default is to leave servers runing when last buffer exits

for what it's worth, i'm actually having trouble with this right now. when i kill a buffer, eglot tries to "politely terminate" the LSP and fails with this:

[eglot] Asking EGLOT (anarcat/(notmuch-message-mode text-mode)) politely to terminate
[jsonrpc] Server exited with status 9
jsonrpc-error: "request id=2 failed:", (jsonrpc-error-code . -32602), (jsonrpc-error-message . "Unexpected params: null"), (jsonrpc-error-data)

this is, fwiw, what the shutdown procedure does, in case you're ready for more lisp:

(defun eglot-shutdown (server &optional _interactive timeout preserve-buffers)
  "Politely ask SERVER to quit.
Interactively, read SERVER from the minibuffer unless there is
only one and it's managing the current buffer.

Forcefully quit it if it doesn't respond within TIMEOUT seconds.
TIMEOUT defaults to 1.5 seconds.  Don't leave this function with
the server still running.

If PRESERVE-BUFFERS is non-nil (interactively, when called with a
prefix argument), do not kill events and output buffers of
SERVER."
  (interactive (list (eglot--read-server "Shutdown which server"
                                         (eglot-current-server))
                     t nil current-prefix-arg))
  (eglot--message "Asking %s politely to terminate" (jsonrpc-name server))
  (unwind-protect
      (progn
        (setf (eglot--shutdown-requested server) t)
        (jsonrpc-request server :shutdown nil :timeout (or timeout 1.5))
        (jsonrpc-notify server :exit nil))
    ;; Now ask jsonrpc.el to shut down the server.
    (jsonrpc-shutdown server (not preserve-buffers))
    (unless preserve-buffers (kill-buffer (jsonrpc-events-buffer server)))))

the error buffer in emacs has this to say:

[client-request] (id:2) Mon Sep  9 14:18:23 2024:
(:jsonrpc "2.0" :id 2 :method "shutdown" :params nil)
[stderr] �[2m2024-09-09T18:18:23.876113Z�[0m �[32m INFO�[0m �[2mtower_lsp::service::layers�[0m�[2m:�[0m shutdown request received, shutting down
[server-reply] (id:2) ERROR Mon Sep  9 14:18:23 2024:
(:jsonrpc "2.0" :error
          (:code -32602 :message "Unexpected params: null")
          :id 2)
[internal] Mon Sep  9 14:18:23 2024:
(:message "Connection state changed" :change "killed\n")

----------b---y---e---b---y---e----------
[stderr] 
[stderr] 
[stderr] nil
[stderr] nil
[stderr] Process EGLOT (wiki/(markdown-mode text-mode)) stderr finished

which is pretty incomprehensible to me, but perhaps it means something to you? *Messages* also have this to say:

for now i've disabled auto-shutdown...

[yitang]

@anarcat Thanks for providing the minimal config, it works well.

To add to that, the eldoc command shows the reasons (e.g. there are two spaces), and eglot-code-actions to select the suggestions (e.g. replace two spaces with one).

[sbromberger]

@elijah-potter - here's the Helix configuration. It really couldn't be more straightforward:

[language-server.harper-ls]
command = "harper-ls"
args = ["--stdio"]