Emacs: Add lsp-treemacs.

init.d/basics/ui.el

@@ -1,6 +1,6 @@
 ;;; ui.el --- Configure user interfaces. -*- lexical-binding: t; -*-
 
-;; Time-stamp: <2019-12-28T06:49:51+0100>
+;; Time-stamp: <2020-01-20T19:46:38+0100>
 
 ;;; Commentary:
 ;; * treemacs
@@ -10,6 +10,7 @@
 
 ;; Directory tree.
 (use-package treemacs
+  :pin melpa                            ; We need > 2.6 for lsp-treemacs.
   :demand t
   :after (display-line-numbers)
 

init.d/programming/common.el

@@ -1,6 +1,6 @@
 ;;; common.el --- Common programming settings. -*- lexical-binding: t; -*-
 
-;; Time-stamp: <2020-01-20T19:27:48+0100>
+;; Time-stamp: <2020-01-20T19:53:44+0100>
 
 ;;; Commentary:
 
@@ -355,6 +355,17 @@
   (use-package lsp-ivy
     :after (lsp-mode ivy)
     )
+
+  ;; Integration between lsp-mode and treemacs.
+  (use-package lsp-treemacs
+    :after (treemacs lsp-mode)
+
+    :bind
+    (:map lsp-ui-mode-map
+          ("<f7>" . lsp-treemacs-errors-list) ; Use treemacs for error list.
+          ("M-i" . lsp-treemacs-symbols)      ; Display symbols using treemacs.
+          )
+    )
   ) ; unless slow-computer.
 
 (provide 'programming/common)