Could not find emacs-ccls in melpa about emacs-ccls

[MaskRay]

Still waiting for melpa/melpa#5405

Before it is merged, you may use:

;; https://github.com/MaskRay/Config/blob/master/home/.config/doom/modules/private/my-cc/config.el
(use-package! ccls
  :load-path "~/Dev/Emacs/emacs-ccls"
  :init (add-hook 'c-mode-common-hook #'+ccls//enable)
  :config
  ;; overlay is slow
  ;; Use https://github.com/emacs-mirror/emacs/commits/feature/noverlay
  (setq ccls-sem-highlight-method 'font-lock)
  (ccls-use-default-rainbow-sem-highlight)
  (setq ccls-extra-init-params
        '(:completion (:detailedLabel t) :xref (:container t)
                      :diagnostics (:frequencyMs 5000)))

  (require 'projectile)
  (add-to-list 'projectile-globally-ignored-directories ".ccls-cache")

  (evil-set-initial-state 'ccls-tree-mode 'emacs)
  (set! :company-backend '(c-mode c++-mode) '(company-lsp))
  )

[ramsayleung]

As you said, in order to use ccls, I have to download ccls to my .emacs.d, and load it manually. By the way, it seems set! is a customized macro, because I could not find any information about it. It seems what (set! :company-backend '(c-mode c++-mode) '(company-lsp)) means is when major mode are c-mode or c++-mode, setting company-backend to company-lsp. Thus I change it to :

;;; backends for lsp-mode
(use-package company-lsp
  :ensure t
  :defer t
  :init (progn
	  (add-hook 'lsp-mode-hook (lambda ()
				     (add-to-list 'company-backends 'company-lsp)))
	  ))

This statement adds company-lsp to company-backends when lsp-mode is enabled. Personally, I prefer

(with-eval-after-load 'projectile
  (add-to-list 'projectile-globally-ignored-directories ".ccls-cache")
  )

rather than

require 'projectile)
  (add-to-list 'projectile-globally-ignored-directories ".ccls-cache")

In the end, (add-to-list 'projectile-globally-ignored-directories ".ccls-cache") should change to (add-to-list 'projectile-globally-ignored-directories "*.ccls-cache"),or it only ignores top level directory.

[MaskRay]

As you said, in order to use ccls, I have to download ccls to my .emacs.d, and load it manually.

Yeah not very convenient for now..

(set! :company-backend '(c-mode c++-mode) '(company-lsp))

This a macro defined in doom-emacs (the Emacs distribution I use) https://github.com/hlissner/doom-emacs/blob/develop/core/core-lib.el#L238

It sets the buffer-local variable company-backends to (company-lsp) somehow.

(with-eval-after-load 'projectile

Thanks for your advice. Updated my config

should change to (add-to-list 'projectile-globally-ignored-directories "*.ccls-cache")

.ccls-cache should be sufficient.

0. When a c-mode c++-mode file is opened
1. The mode hook kicks in and initializes emacs-ccls
2. emacs-ccls uses ccls-project-root-matchers to locate the project root
3. lsp-mode spawns ccls (server) and and sends the initialize request to the ccls process, with rootUri (project root) in the parameter.
4. The ccls server takes rootUri as the project root and creates .ccls-cache under it.

.ccls-cache will not appear in other directories so I do not bother using *.ccls-cache.

For larger C/C++ projects with subprojects, .ccls-root should be put in the parent project directory. I may not have explained it well, clarification (it is publicly editable) welcomed :)

[ramsayleung]

Sorry for missing the FAQ, because I haven't set .ccls-root in the root project, so ccls just generates .ccls-cache for each subproject. Even though I am not familiar with ccls/emacs-ccls, I think your explanation is clear enough.

[MaskRay]

The PR has been merged.

https://melpa.org/#/ccls

[ramsayleung]

Congrats!