Keybinding breaks undo-tree with evil

Question

A few months ago I noticed undo-tree was not working properly for me, though it had never been a problem in the past. Whenever I opened an existing file on my computer and edited it, trying to undo would give me a message saying "Undo-tree mode not enabled in buffer." If I manually enabled undo-tree mode per buffer everything would work fine, however that had never been the case before. It simply worked with my config.

Strangely it seems to be a key binding causing the problem. I'm using general.el to do my keybinds. Here is a minimal config that reproduces the issue:

(require 'package)

(add-to-list 'package-archives '("melpa" . "https://melpa.org/packages/") t)
(package-initialize)

(unless package-archive-contents
  (package-refresh-contents))

(unless (package-installed-p 'use-package)
  (package-install 'use-package))

(require 'use-package)
(setq use-package-always-ensure t)

(use-package evil
  :init
  (setq evil-want-integration t)
  (setq evil-want-keybinding nil)
  (setq evil-want-C-u-scroll t)
  (setq evil-want-C-i-jump nil)
  (setq evil-ex-search-vim-style-regexp t)
  (setq evil-respect-visual-line-mode t)
;  (defvar my/cur-window nil)
  :config
  (evil-mode 1)
  (setq evil-vsplit-window-right t)
  (setq evil-split-window-below t)
  (setq evil-want-fine-undo t))

(use-package evil-collection
  :after evil
  :config
  (evil-collection-init))

 (use-package general
   :ensure t
   :config (general-evil-setup t))

(use-package undo-tree
  :ensure t
  :config
  (evil-set-undo-system 'undo-tree)
  (global-undo-tree-mode 1))

 (nvmap :keymaps 'override
   "/"  'swiper
  "C-/" 'counsel-rg)

If you remove the very last line (the counsel-rg binding) things seem to work as they should. I don't understand what's causing this issue, and how to fix it.

Answer 1

In undo-tree.el there is a turn-on-undo-tree-mode function. One of the things it does before turning on undo-tree-mode is checking if the default undo/redo keybindings have been overridden. It does this using a function called (undo-tree-overridden-undo-bindings-p). I forced that to always return nil, which seems to have solved the problem:

  (advice-add 'undo-tree-overridden-undo-bindings-p
              :override
              (lambda () nil))

Whether or not this will have any unintended consequences, I'm not sure.