Use helm fuzzy search inside ranger inside spacemacs

Question

I am using ranger within spacemacs. One useful feature an explorer in windows (directory opus) I used has, is that by pressing keys it automatically starts to filter files with names corresponding to the keys.

Is there a way to use helms fuzzy search as the default mode inside ranger windows, which then filters the files and directories according to the fuzzy input and to be able to toggle the mode off when desired?

Answer 1

EDIT START

It is more reliable to add advice to ranger and deer to try to ensure that helm-find-files is always enabled when ranger and dired are called (as opposed to adding a hook to ranger-mode-hook which is only called once the buffer is created). This should fix the problem of helm-find-files sometimes not being called immediately.

(with-eval-after-load 'ranger
  (advice-add #'deer :after #'+enable-helm-find-files)
  (advice-add #'ranger :after #'+enable-helm-find-files))

EDIT END

activate from newly created ranger buffers

helm-find-files might be what you're looking for. You can add it as a hook to ranger-mode-hook. I recommend naming it as I did so (1) you can easily remove it and (2) the hooks contents are more readable.

(defun +call-helm-find-files ()
  (interactive)
  (call-interactively #'helm-find-files))

(add-hook 'ranger-mode-hook #'+call-helm-find-files)

system to switch buffers

Adding a hook to ranger-mode-hook does not answer your original question which was to enable fuzzy searching whenever you switch to a ranger buffer. Adding a hook will only work when ranger-mode is enabled. In practice, this means when you call ranger mode (M-x ranger or M-x deer) and ranger creates a brand new ranger buffer. However if you're switching from a buffer to an existing ranger buffer ranger-mode-hook will not be run and therefore helm-find-files will not be called.

To call helm-find-files upon switching to a ranger buffer and to do it in a thorough, not as hacky way, I would recommend adapting some of the code from doom-emacs. Currently, there is no hook that runs after switching a buffer. This code sets up such a hook. I adapted it here.

switch hook

(defvar +after-switch-to-buffer-hook nil
  "Hook run after switched to buffer.")

advice to switch-to-buffer

(defun +run-switch-buffer-hooks (orig-fn buffer-or-name &rest args)
  "Run ‘+after-switch-buffer-hook’."
  (if (or +inhibit-switch-buffer-hooks
          (eq (current-buffer) (get-buffer buffer-or-name))
          (and (eq orig-fn #'switch-to-buffer) (car args)))
      (apply orig-fn buffer-or-name args)
    (let ((+inhibit-switch-buffer-hooks t))
      (when-let (buffer (apply orig-fn buffer-or-name args))
        (with-current-buffer (if (windowp buffer)
                                 (window-buffer buffer)
                               buffer)
          (run-hooks '+after-switch-to-buffer-hook))
        buffer))))

advice to previous-buffer and next-buffer

(defun +run-prev-or-next-buffer-hooks (orig-fn &rest args)
  (if +inhibit-switch-buffer-hooks
      (apply orig-fn args)
    (let ((+inhibit-switch-buffer-hooks t))
      (when-let (buffer (apply orig-fn args))
        (with-current-buffer buffer
          (run-hooks '+after-switch-to-buffer-hook))
        buffer))))

inhibit switch-buffer hooks

(defvar +inhibit-switch-buffer-hooks nil
  "Letvar for inhibiting `+after-switch-buffer-hook'. Do not set this directly.")

toggle

I checked this code and it worked for me. But my checking was not exhaustive so I wrote this function so you can enable and disable the switch buffer hook.

(defvar +enable-switch-buffer-hooks nil
  "Whether to enable switch buffer hooks.")

(defun +toggle/switch-window-advice ()
  (interactive)
  (setq +enable-switch-buffer-hooks (not +enable-switch-buffer-hooks))
  (if +enable-switch-buffer-hooks
      (progn
        (message "disabled switch buffer hooks.")
        (advice-remove #'switch-to-buffer #'+run-switch-buffer-hooks)
        (advice-remove #'display-buffer #'+run-switch-buffer-hooks)
        (advice-remove #'switch-to-next-buffer #'+run-prev-or-next-buffer-hooks)
        (advice-remove #'switch-to-prev-buffer #'+run-prev-or-next-buffer-hooks))
    (message "enabled switch buffer hooks")
    (advice-add #'switch-to-buffer :around #'+run-switch-buffer-hooks)
    (advice-add #'display-buffer :around #'+run-switch-buffer-hooks)
    (advice-add #'switch-to-next-buffer :around #'+run-prev-or-next-buffer-hooks)
    (advice-add #'switch-to-prev-buffer :around #'+run-prev-or-next-buffer-hooks)))

disable all

In case something goes wrong, you can disable everything with this.

(defun +disable-helm-find-files-all ()
  "Disable the whole thing."
  (interactive)
  (setq +enable-switch-buffer-hooks nil)
  (+toggle/switch-window-advice)
  (remove-hook 'ranger-mode-hook #'+call-helm-find-files))

inhibited files

This list is for the buffers you disable with +toggle/find-file-inhibited.

(defvar +inhibited-find-file-buffers nil
  "List of ranger buffers that shouldn’t do ‘helm-find-files’ on switch.")

toggle inhibited

This is the toggling functionality you requested. You can call this while on a ranger buffer and that buffer will not trigger helm-find-files when you switch to it.

(defun +toggle/find-file-inhibited ()
  "Make current buffer not call ‘helm-find-files’."
  (interactive)
  (push (current-buffer) +inhibited-find-file-buffers))

activate helm-find-files when entering buffer

This is the hook to actually call helm-find-files. It checks to see if the current buffer is a ranger buffer and whether its not a member of those in +inhibited-find-file-buffers.

(defun +enable-helm-find-files ()
  "Enable ‘helm-find-files’ in ranger buffers."
  (when (and (eq major-mode 'ranger-mode)
             (not (member (current-buffer) +inhibited-find-file-buffers)))
    (call-interactively #'helm-find-files)))

(add-hook '+after-switch-to-buffer-hook #'+enable-helm-find-files)