nixos/pkgsets/emacs/company.nix

{ config, lib, pkgs, ... }:

with lib;

let
  # Source: https://github.com/Henry/dot-emacs/blob/master/my-lisp/company-pcomplete.el
  company-pcomplete = pkgs.writeText "company-pcomplete.el" ''
    ;;; company-pcomplete.el --- company-mode pcomplete backend -*- lexical-binding: t -*-

    ;; Copyright (C) 2016 Free Software Foundation, Inc.

    ;; Author: Henry G. Weller

    ;; This file is part of GNU Emacs.

    ;; GNU Emacs is free software: you can redistribute it and/or modify
    ;; it under the terms of the GNU General Public License as published by
    ;; the Free Software Foundation, either version 3 of the License, or
    ;; (at your option) any later version.

    ;; GNU Emacs is distributed in the hope that it will be useful,
    ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
    ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    ;; GNU General Public License for more details.

    ;; You should have received a copy of the GNU General Public License
    ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.


    ;;; Commentary:
    ;;
    ;; Based on `ac-pcomplete', see https://www.emacswiki.org/emacs/EshellCompletion
    ;; and `pcomplete`, see pcomplete.el.

    ;;; Code:

    (require 'company)
    (require 'cl-lib)
    (require 'pcomplete)

    (defgroup company-pcomplete nil
      "Completion backend using pcomplete."
      :group 'company)

    (defvar company-pcomplete-available 'unknown)

    (defun company-pcomplete--prefix ()
      (let* ((pcomplete-stub)
             pcomplete-seen
             pcomplete-norm-func
             pcomplete-args
             pcomplete-last pcomplete-index
             (pcomplete-autolist pcomplete-autolist)
             (pcomplete-suffix-list pcomplete-suffix-list))
        (pcomplete-completions)
        (buffer-substring (pcomplete-begin) (point))))

    (defun company-pcomplete--candidates ()
      (let* ((pcomplete-stub)
             (pcomplete-show-list t)
             pcomplete-seen pcomplete-norm-func
             pcomplete-args pcomplete-last pcomplete-index
             (pcomplete-autolist pcomplete-autolist)
             (pcomplete-suffix-list pcomplete-suffix-list)
             (candidates (pcomplete-completions))
             (prefix (buffer-substring (pcomplete-begin) (point)))
             ;; Collect all possible completions for the current stub
             (cnds (all-completions pcomplete-stub candidates))
             (bnds (completion-boundaries pcomplete-stub candidates nil ""))
             (skip (- (length pcomplete-stub) (car bnds))))
        ;; Replace the stub at the beginning of each candidate by the prefix
        (mapcar #'(lambda (cand) (concat prefix (substring cand skip))) cnds)))

    (defun company-pcomplete-available ()
      (when (eq company-pcomplete-available 'unknown)
        (condition-case _err
            (progn
              (company-pcomplete--candidates)
              (setq company-pcomplete-available t))
          (error
           (message "Company: pcomplete not found")
           (setq company-pcomplete-available nil))))
      company-pcomplete-available)

    ;;;###autoload
    (defun company-pcomplete (command &optional _arg &rest ignored)
      "`company-mode' completion backend using `pcomplete'."
      (interactive (list 'interactive))
      (cl-case command
        (interactive (company-begin-backend 'company-pcomplete))
        (prefix (when (company-pcomplete-available)
                  (company-pcomplete--prefix)))
        (candidates (company-pcomplete--candidates))
        (sorted t)))

    (provide 'company-pcomplete)
  '';
in mkIf (elem "emacs::company" config.machine.pkgs) {
  programs.emacs.init.usePackage = {
    company = {
      enable = true;
      diminish = [ "company-mode" ];
      hook = [ "(after-init . global-company-mode)" ]
             ++ optional (elem "emacs::rust" config.machine.pkgs)
               ''(rust-mode . (lambda () (setq company-backends '((company-capf :with company-yasnippet)))))'';
      bind = { "\t" = "'company-complete-common"; };
      init = ''(require 'ffap)'';
      config = ''
        ;; (setq company-tooltip-align-annotations t)
        (setq company-idle-delay 0.3
              company-show-numbers t)

        ${optionalString
          (elem "emacs::org" config.machine.pkgs) ''
            (load-file "${company-pcomplete}")''
         }
      '';
      extraConfig = ''
        :bind (:map company-mode-map
                    ([remap completion-at-point] . company-complete-common)
                    ([remap complete-symbol] . company-complete-common))
      '';
    };

    company-box = {
      enable = true;
      hook = [ "(company-mode . (lambda () (company-box-mode)))" ];
      config = ''
        (setq company-box-icons-alist 'company-box-icons-all-the-icons)


        (setq company-box-icons-lsp
          `(( 1  . ,(all-the-icons-faicon "file-text-o" :v-adjust -0.0575))     ; Text
            ( 2  . ,(all-the-icons-faicon "cube" :v-adjust -0.0575))            ; Method
            ( 3  . ,(all-the-icons-faicon "cube" :v-adjust -0.0575))            ; Function
            ( 4  . ,(all-the-icons-faicon "cube" :v-adjust -0.0575))            ; Constructor
            ( 5  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Field
            ( 6  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Variable
            ( 7  . ,(all-the-icons-faicon "cog" :v-adjust -0.0575))             ; Class
            ( 8  . ,(all-the-icons-faicon "cogs" :v-adjust -0.0575))            ; Interface
            ( 9  . ,(all-the-icons-alltheicon "less"))                          ; Module
            (10  . ,(all-the-icons-faicon "wrench" :v-adjust -0.0575))          ; Property
            (11  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Unit
            (12  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Value
            (13  . ,(all-the-icons-material "content_copy" :v-adjust -0.2))     ; Enum
            (14  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Keyword
            (15  . ,(all-the-icons-material "content_paste" :v-adjust -0.2))    ; Snippet
            (16  . ,(all-the-icons-material "palette" :v-adjust -0.2))          ; Color
            (17  . ,(all-the-icons-faicon "file" :v-adjust -0.0575))            ; File
            (18  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Reference
            (19  . ,(all-the-icons-faicon "folder" :v-adjust -0.0575))          ; Folder
            (20  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; EnumMember
            (21  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Constant
            (22  . ,(all-the-icons-faicon "cog" :v-adjust -0.0575))             ; Struct
            (23  . ,(all-the-icons-faicon "bolt" :v-adjust -0.0575))            ; Event
            (24  . ,(all-the-icons-faicon "tag" :v-adjust -0.0575))             ; Operator
            (25  . ,(all-the-icons-faicon "cog" :v-adjust -0.0575))             ; TypeParameter
            ))
      '';
    };
    all-the-icons = { enable = true; };
    company-jedi = {
      enable = (elem "emacs::elpy" config.machine.pkgs);
    };
  };
  fonts.fonts = pkgs.emacs-all-the-icons-fonts.all;
}