lsp-keymap-prefix not working

[haoyuan80s]

Hi, I set prefix for lsp-command-keymap by (setq lsp-keymap-prefix "C-S-l").
With describe variable i can see:

But all the lsp functions are still have s-l as prefix:

How set the prefix correctly?

[Lenbok]

It is counter-intuitive how that doesn't work. I think it depends on when you call the setq. In my init I have:

(use-package lsp-mode
  :commands lsp
  :init
  (setq lsp-keymap-prefix "C-c l")
  :config
  (define-key lsp-mode-map (kbd "C-c l") lsp-command-map)
  (require 'lsp-clients)
  :hook (lsp-mode . lsp-enable-which-key-integration))

The define-key gets the actual commands working with the desired prefix, and the setq ensures that the which-key integration is using the correct prefix.

The lsp-mode docs show customization of the prefix by putting the setq before (outside) the use-package so that probably works as well, although it seems wrong to have it outside of the use-package.

[yyoncho]

the issue is that you should set the prefix before lsp-mode has been loaded and I am not quite sure how to achieve that with use-package.

:config
(define-key lsp-mode-map (kbd "C-c l") lsp-command-map)

This works fine too.

I am closing the issue but it could be used for further discussions.

[haoyuan80s]

Yes, the key is "set the prefix before lsp-mode has been loaded ".

My problem was that I loaded ccls before lsp-mode. Seems that ccls loaded lsp-mode (without set the prefix). I fixed it by adding ":after lsp" in when loading ccls package: (use-package ccls :after lsp). Then, I am able to set the prefix in the "natural way":

(use-package lsp-mode
    :init (setq lsp-keymap-prefix "C-c l")

[phillord]

I know that this issue has been closed, but I wonder whether it was worth revisiting. I have just hit the same problem caused by loading lsp-ui before lsp. Moving (setq lsp-keymap-prefix "blah") to top-level doesn't solve this problem.

This could be implemented by having a lsp-remap-prefix function and documented this as the main mechanism. This could also be added to the lsp-keymap-prefix customize code also, as I guess this won't work in without a restart.

Happy to send a PR if this would seem to be reasonable.

[yyoncho]

@phillord what about using setter for the defcustom?

[phillord]

@yyoncho Not sure I understand. It doesn't have one at the moment. As far as I can see, we'd just need to call

  (define-key map (kbd lsp-keymap-prefix) lsp-command-map)

and then re-run the which-key integration. So a simple function which wraps that lot up, updated documentation and updating the defcustom to use this as a set function. Is that enough, or am I missing something. Can change this into a PR if wanted.

[yyoncho]

I meant instead of having this as part of a separate function it seems like having it part of the setter might be more convenient.

(defcustom lsp-keymap-prefix "s-l"
  "lsp-mode keymap prefix."
  :group 'lsp-mode
  :type 'string
  :package-version '(lsp-mode . "6.3")
  :set (lambda (sym val)
         ;; unbind old value
         ;; bind new value, update which-key, etc.
         ))

[phillord]

I'd go the other way. Have this as a function, then call that function as the :set from defcustom. That way it would also work for people not using custom. There isn't a convienient way to call defcustom settters that I know of.

[kflu]

It is counter-intuitive how that doesn't work. I think it depends on when you call the setq. In my init I have:

(use-package lsp-mode
  :commands lsp
  :init
  (setq lsp-keymap-prefix "C-c l")
  :config
  (define-key lsp-mode-map (kbd "C-c l") lsp-command-map)
  (require 'lsp-clients)
  :hook (lsp-mode . lsp-enable-which-key-integration))

The define-key gets the actual commands working with the desired prefix, and the setq ensures that the which-key integration is using the correct prefix.

The lsp-mode docs show customization of the prefix by putting the setq before (outside) the use-package so that probably works as well, although it seems wrong to have it outside of the use-package.

Even if I do this, C-c l is still not registered as the binding. Only if I put

  (define-key lsp-mode-map (kbd "C-c l") lsp-command-map)

outside use-package after all the use-packages did it work.

I still prefer to put define-key inside use-package, so does that mean I have some other kind of conflicts going on in my init.el?