problem in `delete-directory` with enabled `delete-by-removing-to-trash`

Question

There is a strange behavior of delete-directory function with enabled flag delete-by-removing-to-trash. It deletes files one by one instead of applying move-file-to-trash to the directory. As a result emacs deletes big directories slowly and there are many files in the trash after deleting, so it is impossible to restore the directory.

Example: Directory structure:

ddd/
   ccc/
       1.txt

There are three files in the trash after deleting ddd:

trash/
    ddd/
    ccc/
    1.txt

instead of one:

trash/
    ddd/

• It is very slow, because emacs traverse directory recursively.
• I can't restore deleted directory.

What i need is exactly the same behavior as of move-file-to-trash. But it should be transparent (i.e. 'D x' in dired mode). How to solve the problem? As a temporary solution i see the making advice function for `delete-directory'.

Answer 1

As a temporary workaround i use:

(setq delete-by-moving-to-trash t)

(defadvice dired-delete-file (around
                              activate-move-to-trash
                              activate
                              compile)
  (if delete-by-moving-to-trash
      (move-file-to-trash (ad-get-arg 0))
    ad-do-it))

Answer 2

Here's my whole system. If you look at the bottom you'll see a nearly identical defadvice to Andreo's.

;;; trash-settings.el - Intelligent integration with system trash

;; Use the system trash, except for temp files and stuff
(require 'cl)

(defcustom system-trash-exclude-names
  nil
  "List of file names to exclude from system trash.
The names in this variable are matched only against the basename
of the file to be deleted."
  :type '(repeat string)
  :group 'trash)

(defcustom system-trash-exclude-paths
  nil
  "List of absolute paths to exclude from system trash.
If a path to a directory is excluded, then all the contents of that directory are also excluded."
  :type '(repeat string)
  :group 'trash)

(defcustom system-trash-exclude-matches
  nil
  "List of regexps or functions matching file names to exclude from system trash.
The matches are only applied against the file name, not the path."
  :type '(repeat (choice regexp function))
  :group 'trash)

(defcustom system-trash-exclude-path-matches
  nil
  "List of regexps or functions matching paths to exclude from system trash.
The matches are applied against the full path."
  :type '(repeat (choice regexp function))
  :group 'trash)

(defun call-process-discard-output (program &rest args)
  "Execute program with args without saving any output.
In particular, no temp files are created."
  (eval (append `(call-process ,program nil nil nil) args)))

(defun string-begins-with-p (string beginning)
  "Return t if and only if string begins with beginning"
  (string-match-p (concat "^" (regexp-quote beginning)) string))

(defun file-excluded-from-system-trash-p (path)
  "Returns non-nil if file name is excluded from trash."
  (let ((basename (file-name-nondirectory path)))
    (or
     (some (apply-partially 'string= basename)
           system-trash-exclude-names)
     (some (apply-partially 'string-begins-with-p path)
           system-trash-exclude-paths)
     (some (lambda (match)
             (funcall
              (cond ((stringp match) 'string-match-p)
                    ((functionp protected-match) 'funcall)
                    (t 'ignore))
              match
              basename))
           system-trash-exclude-matches)
     (some (lambda (match)
             (funcall
              (cond ((stringp match) 'string-match-p)
                    ((functionp protected-match) 'funcall)
                    (t 'ignore))
              match
              path))
           system-trash-exclude-path-matches))))

(defun trash-or-rm (filename)
  "Attempt to move a file to the trash. If this fails, simply delete it.
This guarantees that any deletable file will either be trashed or deleted.
If the file is excluded from the trash, it is simply deleted."
  (unless (file-excluded-from-system-trash-p filename)
    (ignore-errors
      (call-process-discard-output "gvfs-trash" filename)))
  (when (file-exists-p filename)
    (call-process-discard-output "rm" "-rf" filename)))

(defalias 'system-move-file-to-trash 'trash-or-rm)

(defadvice delete-directory (around no-recursive-trash activate)
  "When trashing a directory, there's no need to trash its contents first."
  (if delete-by-moving-to-trash
    (move-file-to-trash directory)
    ad-do-it))

(defadvice dired-delete-file (around no-recursive-trash activate)
  "When trashing a directory, there's no need to trash its contents first.
There's also no need to ask, because it's undoable."
  (if delete-by-moving-to-trash
      (move-file-to-trash file)
    ad-do-it))

Edit: I should mention that my solution above requires the gvfs-trash command-line program, which is associated with GNOME. You can replace this with trash from the trash-cli package if you don't use GNOME.