tools/lsp: defer lsp init until buffer is visible

modules/tools/lsp/autoload.el

@@ -1,31 +1,4 @@
 ;;; feature/lsp/autoload.el -*- lexical-binding: t; -*-
 
 ;;;###autodef
-(defun lsp! (&optional arg)
-  "Enable `lsp-mode' in the current buffer.
-
-Meant to be a lighter alternative to `lsp', which is too eager about
-initializing lsp-ui-mode, company, yasnippet and flycheck. Instead, these have
-been moved out to their respective modules, or these hooks:
-
-+ `+lsp-init-company-h' (on `lsp-mode-hook')
-+ `+lsp-init-ui-flycheck-or-flymake-h' (on `lsp-ui-mode-hook')"
-  (if (bound-and-true-p lsp-mode)
-      t
-    (require 'lsp-mode)
-    (when lsp-auto-configure
-      (require 'lsp-clients))
-    (when (and (buffer-file-name)
-               (setq-local
-                lsp--buffer-workspaces
-                (or (lsp--try-open-in-library-workspace)
-                    (lsp--try-project-root-workspaces
-                     (equal arg '(4))
-                     (and arg (not (equal arg 1)))))))
-      (prog1 (lsp-mode 1)
-        (lsp--info
-         "Connected to %s."
-         (apply
-          #'concat (mapcar
-                    (lambda (it) (format "[%s]" (lsp--workspace-print it)))
-                    lsp--buffer-workspaces)))))))
+(defalias 'lsp! #'lsp-deferred)

modules/tools/lsp/config.el

@@ -20,10 +20,35 @@ This can be a single company backend or a list thereof. It can be anything
     :definition 'lsp-find-definition
     :references 'lsp-find-references)
 
-  ;; The original `lsp' initializes too much, too quickly. Things like flycheck,
-  ;; company, and yasnippet. Doom's modules already handle these just fine, so
-  ;; leave it to us.
-  (advice-add #'lsp :override #'lsp!)
+  (defadvice! +lsp-init-a (&optional arg)
+    :override #'lsp
+    "Enable `lsp-mode' in the current buffer.
+
+Meant to be a lighter alternative to `lsp', which is too eager about
+initializing lsp-ui-mode, company, yasnippet and flycheck. Instead, these have
+been moved out to their respective modules, or these hooks:
+
++ `+lsp-init-company-h' (on `lsp-mode-hook')
++ `+lsp-init-ui-flycheck-or-flymake-h' (on `lsp-ui-mode-hook')"
+    (interactive "P")
+    (if (bound-and-true-p lsp-mode) t
+      (require 'lsp-mode)
+      (when lsp-auto-configure
+        (require 'lsp-clients))
+      (when (and (buffer-file-name)
+                 (setq-local
+                  lsp--buffer-workspaces
+                  (or (lsp--try-open-in-library-workspace)
+                      (lsp--try-project-root-workspaces
+                       (equal arg '(4))
+                       (and arg (not (equal arg 1)))))))
+        (prog1 (lsp-mode 1)
+          (lsp--info
+           "Connected to %s."
+           (apply
+            #'concat (mapcar
+                      (lambda (it) (format "[%s]" (lsp--workspace-print it)))
+                      lsp--buffer-workspaces)))))))
 
   ;; Don't prompt to restart LSP servers while quitting Emacs
   (add-hook! 'kill-emacs-hook (setq lsp-restart 'ignore)))