Magit sets auto-revert mode — annoying!

Question

I've recently upgraded to Magit 2.10.3 and Emacs 25.2.1.

My full config is: Magit 2.10.3, Git 2.13.5 (Apple Git-94), Emacs 25.2.1, darwin.

I was previously on Magit 2.3.1 and Emacs 24.4.1.

Now, when I do a magit-status any open buffers within the project are changed to have auto-revert mode turned on.

Previously, the behaviour was only to revert buffers when Magit operations were performed (eg using Magit to checkout a different commit would revert any buffers whose files had changed). auto-revert mode was never turned on (or if it was it was only temporarily, and I didn't notice it).

Is there a way to get the old behaviour?

---

UPDATE #1:

Based on tarsius's answer, I've done the following:

(with-eval-after-load 'magit-autorevert
  (defalias 'magit-auto-revert-buffers 'revert-all-unmodified-buffers)
  (magit-auto-revert-mode -1))

revert-all-unmodified-buffers is something I had lying around:

(defun _revert-all-buffers (buffer-predicate)
  (dolist (buf (buffer-list))
    (with-current-buffer buf
      (when (and (buffer-file-name) (funcall buffer-predicate buf))
        (revert-buffer t t t) )))
  (message "Refreshed open files."))

(defun revert-all-unmodified-buffers ()
  "Refreshes all open unmodified buffers from their files."
  (interactive)
  (_revert-all-buffers (lambda (b) (not (buffer-modified-p b)))))

This kind of works. I guess I could change things so that I only revert buffers in the project directory.

One thing I noticed: whenever I refresh the Magit Status buffer, files get reverted. I don't really want that.

---

UPDATE #2

I believe I have restored the old behaviour, by turning off magit-auto-revert-mode and by doing a (defalias 'magit-auto-revert-buffers ...) that reverts buffers within the repo:

(defun _revert-all-buffers (buffer-predicate)
  (dolist (buf (buffer-list))
    (with-current-buffer buf
      (when (and (buffer-file-name) (funcall buffer-predicate buf))
        (condition-case e
            (revert-buffer t t t)
          (error
           (message "%s" e))))))
  (message "Refreshed open files."))

(defun revert-all-unmodified-buffers-in-git-repo ()
  "Refreshes all open modified buffers in current buffer's Git repo
 from their files."
  (interactive)
  (_revert-all-buffers (lambda (b)
                         (and (not (buffer-modified-p b))
                              (magit-auto-revert-repository-buffer-p b)))))

(with-eval-after-load 'magit-autorevert
  (magit-auto-revert-mode 0)
  (defalias 'magit-auto-revert-buffers
    'revert-all-unmodified-buffers-in-git-repo))

Thanks, tarsius, for pointing me in the right direction.

I wonder if something like this could be supported without having to hack things? (My concern is that my hack might break when I next update Magit.)

Answer 1

(Answering my own question…)

I decided to address the issue I mentioned about files being reverted when I refresh the Magit Status buffer. (BTW, the doc strings for magit-refresh and magit-refresh-all are interesting. Only the latter mentions reverting buffers. Maybe that was the original intention and things have changed over time.)

This is what I have ended up with. I'd be interested in any comments.

I'm also interested in whether this behaviour could be made part of Magit.

;;;; Don't revert buffers other than after performing a Magit operation that
;;;; changes files.
;;;; See https://emacs.stackexchange.com/questions/35701/magit-sets-auto-revert-mode-annoying

;;;; This is more heavy-handed than I would like. A change to a single file
;;;; (eg by discarding changes to the file) causes all buffers in the repo
;;;; to be reverted.

(defun _revert-all-buffers (buffer-predicate)
  (dolist (buf (buffer-list))
    (with-current-buffer buf
      (when (and (buffer-file-name) (funcall buffer-predicate buf))
        (condition-case e
            (revert-buffer t t t)
          (error
           (message "%s" e))))))
  (message "Refreshed open files."))

(defun revert-all-unmodified-buffers-in-git-repo ()
  "Refreshes all open unmodified buffers in current buffer's Git repo
 from their files."
  (interactive)
  (_revert-all-buffers (lambda (b)
                         (and (not (buffer-modified-p b))
                              (magit-auto-revert-repository-buffer-p b)))))

(defun -nomis/fix-magit-auto-revert/2.10.3 ()

  (with-eval-after-load 'magit-autorevert

    (magit-auto-revert-mode 0)

    (defvar *nomis/magit-revert-buffers?* t)

    (defun nomis/magit-refresh ()
      "A replacement for the \"g\" key binding in `magit-mode-map`. This does
not revert buffers."
      (interactive)
      (let* ((*nomis/magit-revert-buffers?* nil))
        (magit-refresh)))

    (define-key magit-mode-map "g" 'nomis/magit-refresh)

    (advice-add 'magit-auto-revert-buffers
                :around
                (lambda (_)
                  (when *nomis/magit-revert-buffers?*
                    (revert-all-unmodified-buffers-in-git-repo)))
                '((name . -nomis/hack-auto-refresh)))))

(defun -nomis/fix-magit-auto-revert ()
  (cond
   ((equal magit-version "2.10.3")
    (-nomis/fix-magit-auto-revert/2.10.3))
   (t
    (message-box (s-join " "
                         '("Revisit `-nomis/fix-magit-auto-revert`"
                       "for this version of Magit."))))))    

(add-hook 'magit-mode-hook '-nomis/fix-magit-auto-revert)

Answer 2

Try this:

(with-eval-after-load 'magit-autorevert
  (defalias 'magit-auto-revert-buffers 'auto-revert-buffers)
  (magit-auto-revert-mode -1))

Edit: This won't work because auto-revert-buffers assumes that auto-revert-mode is on. It was worth a shot, but this outcome isn't really surprising.

So I am afraid the answer is no. Magit cannot automatically revert without using auto-revert-mode anymore. But you haven't explained why it is annoying that auto-revert-mode is being turned on now. Maybe there's something else that can be done to make you happy.

One thing I noticed: whenever I refresh the Magit Status buffer, files get reverted. I don't really want that.

That already happened before. I am pretty sure every thing you do in Magit that now triggers a revert also did so before. So what action outside of Magit did not use to do so but now does? (Or in other words, how did you notice that something had changed?)