Fix lsp-treemacs to work with latest treemacs

- fixes #142

Author: yyoncho

lsp-treemacs-generic.el

@@ -130,20 +130,23 @@
                                  &optional buffer-name right-click-actions _clear-cache?)
   (let ((buffer (get-buffer-create (or buffer-name "*LSP Lookup*"))))
     (with-current-buffer buffer
-      (treemacs-initialize 'lsp-treemacs-generic-root
-        (lsp-treemacs--set-mode-line-format buffer title)
-        (setq-local face-remapping-alist '((button . default)))
-        (setq-local lsp-treemacs-tree tree)
-        (setq-local treemacs-default-visit-action 'treemacs-RET-action)
-        (setq-local lsp-treemacs--right-click-actions right-click-actions)
-        (setq-local window-size-fixed nil)
-        (setq-local treemacs--width-is-locked nil)
-        (setq-local treemacs-space-between-root-nodes nil)
-        (when treemacs-text-scale
-          (text-scale-increase treemacs-text-scale))
-        (lsp-treemacs-generic-mode t)
-        ;; (when expand-depth (lsp-treemacs--expand 'lsp-treemacs-generic-root expand-depth))
-        )
+      (treemacs-initialize lsp-treemacs-generic-root
+        :with-expand-depth (or expand-depth 0)
+        :and-do (progn
+                  (lsp-treemacs--set-mode-line-format buffer title)
+                  (setq-local face-remapping-alist '((button . default)))
+                  (setq-local lsp-treemacs-tree tree)
+                  (setq-local treemacs-default-visit-action 'treemacs-RET-action)
+                  (setq-local lsp-treemacs--right-click-actions right-click-actions)
+                  (setq-local window-size-fixed nil)
+                  (setq-local treemacs--width-is-locked nil)
+                  (setq-local treemacs-space-between-root-nodes nil)
+                  (when treemacs-text-scale
+                    (text-scale-increase treemacs-text-scale))
+                  (lsp-treemacs-generic-mode t)
+                  ;; (when expand-depth (lsp-treemacs--expand 'lsp-treemacs-generic-root expand-depth))
+
+                  ))
       (current-buffer))))
 
 (provide 'lsp-treemacs-generic)