custom-buffer-local-keys

custom-buffer-local-keys.el

;; JD Smith 2024, based on https://www.emacswiki.org/emacs/BufferLocalKeys
(defvar-local custom-buffer-local-keys nil
    "Key-bindings to be set up local to the current buffer.
A single (KEY . BINDING) cons or list of such conses, of the form
`bind-keys' accepts.  Set this as a file-local variable to make
bindings local to that buffer only.")

;; Only include this if you trust the files you open
(put 'custom-buffer-local-keys 'safe-local-variable 'consp)

(defvar-local my/custom-buffer-local-map nil)
(defun my/process-custom-buffer-local-keys ()
  "Setup and enable a minor mode if custom-buffer-local-keys is non-nil."
  (when (and (boundp 'custom-buffer-local-keys) custom-buffer-local-keys)
    (let ((map my/custom-buffer-local-map)
	  (keys custom-buffer-local-keys))
      (unless map
	(setq map (make-sparse-keymap))
	(set-keymap-parent map (current-local-map))
	(use-local-map (setq my/custom-buffer-local-map map)))
      (unless (consp (car keys)) (setq keys (list keys)))
      (dolist (k keys) (local-set-key (kbd (car k)) (cdr k))))))

(add-hook 'hack-local-variables-hook #'my/process-custom-buffer-local-keys)

Yes you could obviously craft a malicious file that changed a common binding like SPACE to do something nefarious, if you could convince me to download and open that file. There are many ways to do this, and I really doubt this particular custom config would invite targeted attacks.

I've added a warning comment. If you worry about this, you could change the name of the local variable to something distinct like your-initials//custom-buffer-local-keys to limit possible misuse (and don't tell anyone the name you chose).