Add corfu as the main completion framework

flake.nix

@@ -58,20 +58,6 @@
         };
 
         fg42 = app.drv;
-        # fg42-wm = pkgs.callPackage ./nix/fg42
-        #   {
-        #     inherit nixpkgs;
-        #     modules = [
-        #       ./nix/modules/editor
-        #       ./nix/modules/elisp
-        #       ./nix/modules/graphics
-        #       ./nix/modules/noether
-        #       ./nix/modules/wm
-        #     ];
-        #     extraPackages = {
-        #       noether = inputs.noether.outputs.packages.${system}.default;
-        #     };
-        #   }.drv;
 
         run-test-wm = pkgs.writeShellApplication {
           name = "run-test-wm";
@@ -103,6 +89,7 @@
           type = "app";
           program = "${test-x}/bin/test-x";
         };
+
         apps.default = {
           type = "app";
           program = "${fg42}/bin/fg42";

nix/modules/autocomplete/lisp/fg42/autocomplete.el

@@ -1,71 +0,0 @@
-;;; FG42 --- The mighty editor for the emacsians -*- lexical-binding: t; -*-
-;;
-;; Copyright (c) 2010-2024 Sameer Rahmani & Contributors
-;;
-;; Author: Sameer Rahmani <lxsameer@gnu.org>
-;; URL: https://devheroes.codes/FG42/FG42
-;; Version: 4.0.0
-;;
-;; This program 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.
-;;
-;; This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
-;;
-;;; Commentary:
-;;; Code:
-(eval-when-compile
-  (require 'fpkg)
-  (require 'fg42/config))
-
-
-(use! company
-  "Company is a modular text completion framework for GNU Emacs."
-  :hook (emacs-startup . global-company-mode)
-  :bind (:map company-active-map
-              ("M-n" . company-select-next)
-              ("M-p" . company-select-previous)
-              ("TAB" . company-complete-common-or-cycle)
-              ("M-d" . company-show-doc-buffer))
-
-  :init
-  ;; Use Company for completion
-  (setq company-show-numbers t)
-  (setq company-idle-delay 0)
-  (setq company-tooltip-limit 20)
-  (setq company-echo-delay 0)
-  (setq company-tooltip-align-annotations t)
-  (setq company-dabbrev-downcase nil)
-
-  :config
-  (setq-default company-backends
-                '(company-capf (company-keywords :separate) company-files))
-  (bind-key [remap completion-at-point] #'company-complete company-mode-map))
-
-
-(use! company-box
-  "A company front-end with icons."
-  :after company
-  :hook (company-mode . company-box-mode))
-
-
-;;;###autoload
-(defun fg42/autocomplete ()
-  "Initialize FG42's auto complete.
-This function is meant to be used with hooks."
-  ;; Why? because if we end up with more auto completion alternatives
-  ;; to company mode, then we can setup them here rather than walking
-  ;; around fixing downstream modules.
-  (interactive)
-  (company-mode t))
-
-
-(provide 'fg42/autocomplete)
-;;; autocomplete.el ends here

nix/modules/completion/default.nix

@@ -22,30 +22,45 @@
 { lib, config, pkgs, makeFG42Drv, ... }:
 with lib;
 let
-  cfg = config.fg42.auto-complete;
+  cfg = config.fg42.completion;
 
   deps =
-    (with pkgs.emacsPackages; [
+    (with pkgs.emacsPackages;
+    optionals (cfg.backend == "corfu") [
+      corfu
+      cape
+    ] ++ optionals (cfg.backend == "company") [
       company
       company-box
     ]);
 
   drv = makeFG42Drv {
-    pname = "autocomplete";
+    pname = "completion";
     version = config.fg42.version;
     buildInputs = deps;
     src = ./.;
   };
+  backendDesc = ''
+    The backend to use for the completion. (default corfu)
+  '';
 in
 {
-  options.fg42.auto-complete.enable = mkAndEnableOption "auto-complete";
+  options.fg42.completion = {
+    enable = mkAndEnableOption "completion";
+    backend = mkOption {
+      type = types.str;
+      default = "corfu";
+      description = backendDesc;
+    };
+  };
 
   config = mkIf cfg.enable {
     fg42.elispPackages = [ drv ] ++ deps;
 
     fg42.requires = [ drv.pname ];
     fg42.vars = [
-      (defVar "auto-complete" cfg.enable "Auto completion for FG42.")
+      (defVar "completion" cfg.enable "Completion for FG42.")
+      (defVar "completion-backend" cfg.backend backendDesc)
     ];
   };
 }

nix/modules/completion/lisp/fg42/completion.el

@@ -0,0 +1,92 @@
+;;; FG42 --- The mighty editor for the emacsians -*- lexical-binding: t; -*-
+;;
+;; Copyright (c) 2010-2024 Sameer Rahmani & Contributors
+;;
+;; Author: Sameer Rahmani <lxsameer@gnu.org>
+;; URL: https://devheroes.codes/FG42/FG42
+;; Version: 4.0.0
+;;
+;; This program 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.
+;;
+;; This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+;;
+;;; Commentary:
+;;; Code:
+(eval-when-compile
+  (require 'fpkg)
+  (require 'fg42/config))
+
+(fg42/config-when "completion-backend" "company"
+  (use! company
+    "Company is a modular text completion framework for GNU Emacs."
+    :hook (emacs-startup . global-company-mode)
+    :bind (:map company-active-map
+                ("M-n" . company-select-next)
+                ("M-p" . company-select-previous)
+                ("TAB" . company-complete-common-or-cycle)
+                ("M-d" . company-show-doc-buffer))
+
+    :init
+    ;; Use Company for completion
+    (setq company-show-numbers t)
+    (setq company-idle-delay 0)
+    (setq company-tooltip-limit 20)
+    (setq company-echo-delay 0)
+    (setq company-tooltip-align-annotations t)
+    (setq company-dabbrev-downcase nil)
+
+    :config
+    (setq-default company-backends
+                  '(company-capf (company-keywords :separate) company-files))
+    (bind-key [remap completion-at-point] #'company-complete company-mode-map))
+
+
+  (use! company-box
+    "A company front-end with icons."
+    :after company
+    :hook (company-mode . company-box-mode)))
+
+
+(fg42/config-when "completion-backend" "corfu"
+  (use! corfu
+    "Corfu enhances in-buffer completion with a small completion popup.
+The current candidates are shown in a popup below or above the point. The candidates
+can be selected by moving up and down. Corfu is the minimalistic in-buffer completion
+counterpart of the Vertico minibuffer UI."
+    :custom
+    (corfu-cycle t)                ;; Enable cycling for `corfu-next/previous'
+    (corfu-auto t)                 ;; Enable auto completion
+    (corfu-separator ?\s)          ;; Orderless field separator
+    (corfu-quit-at-boundary nil)   ;; Never quit at completion boundary
+    ;; (corfu-quit-no-match nil)      ;; Never quit, even if there is no match
+    (corfu-preview-current nil)    ;; Disable current candidate preview
+    (corfu-preselect 'prompt)      ;; Preselect the prompt
+    (corfu-on-exact-match nil)     ;; Configure handling of exact matches
+    (corfu-scroll-margin 5)        ;; Use scroll margin
+    :hook (emacs-startup . global-corfu-mode)))
+
+
+;;;###autoload
+(defun fg42/setup-completion ()
+  "Initialize FG42's completion system.
+This function is meant to be used with hooks."
+  ;; Why? because if we end up with more auto completion alternatives
+  ;; to corfu or company mode, then we can setup them here rather than walking
+  ;; around fixing downstream modules.
+  (interactive)
+
+  (fg42/config-when "completion-backend" "company"
+    (company-mode t)))
+
+
+(provide 'fg42/completion)
+;;; completion.el ends here

nix/modules/default.nix

@@ -28,7 +28,7 @@ let
     ./minibuffer-vertico
     ./graphics
     ./noether
-    ./autocomplete
+    ./completion
     ./language-server
     ./nix
     ./c-family

nix/modules/editor/lisp/fg42/editor.el

@@ -242,6 +242,12 @@ contextual information."
   (setq tooltip-use-echo-area t)
   (setq x-gtk-use-system-tooltips nil)
 
+  ;; Emacs 30 and newer: Disable Ispell completion function.
+  (setq text-mode-ispell-word-completion nil)
+  ;; Enable indentation+completion using the TAB key.
+  ;; `completion-at-point' is often bound to M-TAB.
+  (setq tab-always-indent 'complete)
+
   ;; Global configurations
   (tool-bar-mode -1)
   (tooltip-mode nil)

nix/modules/unit/lisp/fg42/config.el

@@ -37,6 +37,22 @@
       `,default)))
 
 
+(defmacro fg42/config= (key value)
+  "Check whether config name KEY has the VALUE or not."
+  `(string= (fg42/config-get-or ,key) ,value))
+
+
+(defmacro fg42/config-when (key value &rest body)
+  "Run the BODY only if config KEY has the VALUE."
+  (declare (indent defun))
+  (message ">> %s %s %s" key value (string= (fg42/config-get-or key) value))
+  (if (fg42/config= key value)
+      `(progn
+         ,@body)
+    `(progn
+       (message "nooooo"))))
+
+
 (defmacro with-config (name &rest body)
   "Run the BODY only if the config NAME is set to t."
   (declare (indent defun))