Git Annex and Dired Integration

dired-annex-integration.el

;; Note: Requires dired-hacks, specifically dired-open

(defun my/in-annex-repo-p ()
  (= 0 (call-process "git" nil nil nil "annex" "status")))

(defun my/dired-try-git-annex-get (filename)
  (if (not (my/in-annex-repo-p))
      (signal 'error "File is a symlink to a nonexistent target")
    (with-help-window "*git-annex-get status*"
      (call-process "git" nil (get-buffer "*git-annex-get status*") t "annex" "get" filename)
      (with-current-buffer (get-buffer "*git-annex-get status*")
        (beginning-of-buffer)
        (while (re-search-forward "\C-M" nil t)
          (replace-match ""))))))

(defun my/dired-around-dired-find-file (original-function &rest args)
  (condition-case err
      (apply original-function args)
    (error
     (if (string= (cadr err) "File is a symlink to a nonexistent target")
         (progn
           (my/dired-try-git-annex-get (dired-get-filename nil t))
           (call-interactively #'dired-open-file))
       (signal (car err) (cdr err))))))
(advice-add 'dired-find-file :around #'my/dired-around-dired-find-file)