Rethink lazy-loading of elisp-mode

modules/lang/emacs-lisp/config.el

@@ -1,22 +1,32 @@
 ;;; lang/emacs-lisp/config.el -*- lexical-binding: t; -*-
 
+;; `elisp-mode' is always loaded at startup, so to lazy load its config we need
+;; to be creative. So we configure it the first tiem `emacs-lisp-mode' is run.
+(advice-add #'emacs-lisp-mode :before #'+emacs-lisp|init)
+;; And we remove `elisp-mode' so later invokations of (after! elisp-mode ...)
+;; work as expected.
+(delq 'elisp-mode features)
+
+(defun +emacs-lisp|init (&rest _)
+  ;; Some plugins (like yasnippet) will run `emacs-lisp-mode' early, prematurely
+  ;; triggering this function in a non-ideal environment (`emacs-lisp-mode-hook'
+  ;; is let-bound to nil). This breaks a lot of Doom setters, because they try
+  ;; to add hooks to `emacs-lisp-mode-hook'!
+  ;;
+  ;; This means, in some sessions, elisp-mode is never configured properly, so
+  ;; we have to make extra sure `emacs-lisp-mode' was executed interactively.
+  (when (and emacs-lisp-mode-hook (not delay-mode-hooks))
+    (provide 'elisp-mode)
+    (advice-remove #'emacs-lisp-mode #'+emacs-lisp|init)))
+
+
+;;
+;; Config
+;;
+
 (add-to-list 'auto-mode-alist '("\\.Cask\\'" . emacs-lisp-mode))
 
-(add-hook! 'emacs-lisp-mode-hook
+(after! elisp-mode
-  #'(;; 3rd-party functionality
-     auto-compile-on-save-mode doom|enable-delete-trailing-whitespace
-     ;; fontification
-     rainbow-delimiters-mode highlight-quoted-mode highlight-numbers-mode +emacs-lisp|extra-fontification
-     ;; initialization
-     +emacs-lisp|init-imenu +emacs-lisp|disable-flycheck-maybe))
-
-(defun +emacs-lisp|init (&rest _)
-  ;; Some plugins will run `emacs-lisp-mode' with `emacs-lisp-mode-hook' set to
-  ;; nil (cough yasnippet cough) or its mode hooks delayed. This prematurely
-  ;; fires this function. Most of these setters affect emacs-lisp-mode-hook, so
-  ;; they'd be swallowed up if it's letbound to nil, causing a half-initialized
-  ;; elisp-mode in some sessions.
-  (when (and emacs-lisp-mode-hook (not delay-mode-hooks))
   (set-repl-handler! 'emacs-lisp-mode #'+emacs-lisp/repl)
   (set-eval-handler! 'emacs-lisp-mode #'+emacs-lisp-eval)
   (set-lookup-handlers! 'emacs-lisp-mode :documentation 'info-lookup-symbol)
@@ -30,11 +40,16 @@
                ("advice-add" "advice-remove")
                ("add-hook" "remove-hook")
                ("add-hook!" "remove-hook!")))
-    ;;
-    (advice-remove #'emacs-lisp-mode #'+emacs-lisp|init)))
-(advice-add #'emacs-lisp-mode :before #'+emacs-lisp|init)
 
-(defun +emacs-lisp|extra-fontification ()
+  (add-hook! 'emacs-lisp-mode-hook
+    #'(;; 3rd-party functionality
+       auto-compile-on-save-mode doom|enable-delete-trailing-whitespace
+       ;; fontification
+       rainbow-delimiters-mode highlight-quoted-mode highlight-numbers-mode +emacs-lisp|extra-fontification
+       ;; initialization
+       +emacs-lisp|init-imenu +emacs-lisp|disable-flycheck-maybe))
+
+  (defun +emacs-lisp|extra-fontification ()
     "Display lambda as a smybol and fontify doom module functions."
     (font-lock-add-keywords
      nil `(;; Highlight custom Doom cookies
@@ -42,7 +57,7 @@
            ;; Highlight doom/module functions
            ("\\(^\\|\\s-\\|,\\)(\\(\\(doom\\|\\+\\)[^) ]+\\|[^) ]+!\\)[) \n]" (2 font-lock-keyword-face)))))
 
-(defun +emacs-lisp|init-imenu ()
+  (defun +emacs-lisp|init-imenu ()
     "Improve imenu support with better expression regexps and Doom-specific forms."
     (setq imenu-generic-expression
           '(("Evil Commands" "^\\s-*(evil-define-\\(?:command\\|operator\\|motion\\) +\\(\\_<[^ ()\n]+\\_>\\)" 1)
@@ -61,13 +76,13 @@
             ("Variables" "^\\s-*(defvar\\(?:-local\\)?\\s-+\\(\\(?:\\sw\\|\\s_\\|\\\\.\\)+\\)[[:space:]\n]+[^)]" 1)
             ("Types" "^\\s-*(\\(cl-def\\(?:struct\\|type\\)\\|def\\(?:class\\|face\\|group\\|ine-\\(?:condition\\|error\\|widget\\)\\|package\\|struct\\|t\\(?:\\(?:hem\\|yp\\)e\\)\\)\\)\\s-+'?\\(\\(?:\\sw\\|\\s_\\|\\\\.\\)+\\)" 2))))
 
-(defun +emacs-lisp|disable-flycheck-maybe ()
+  (defun +emacs-lisp|disable-flycheck-maybe ()
     "Disable flycheck-mode if in emacs.d."
     (when (or (not buffer-file-name)
               (cl-loop for dir in (list doom-emacs-dir doom-private-dir)
                        if (file-in-directory-p buffer-file-name dir)
                        return t))
-    (flycheck-mode -1)))
+      (flycheck-mode -1))))
 
 
 ;;