branch: externals/doc-view-follow
commit eb1f6f0ed75a99aae037eeff1a640532fcb585b4
Author: Paul Nelson <ultr...@gmail.com>
Commit: Paul Nelson <ultr...@gmail.com>
Improve advice management
* doc-dual-view.el (doc-dual-view--sync-pages): Only run
synchronization when mode is active.
(doc-dual-view--manage-advice): New function to centralize adding and
removing advice for all functions in doc-dual-view-modes.
(doc-dual-view--some-buffer-active-p): New function to check if any
buffer has the mode enabled.
(doc-dual-view-mode): Refactor to use the new helper functions and
only remove advice when no buffers are using the mode.
---
doc-dual-view.el | 31 ++++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/doc-dual-view.el b/doc-dual-view.el
index e78c07a02d..31183118f9 100644
--- a/doc-dual-view.el
+++ b/doc-dual-view.el
@@ -87,7 +87,8 @@ by adding entries to this list.")
(defun doc-dual-view--sync-pages (&rest _args)
"Sync pages between windows showing the same document."
- (unless doc-dual-view--sync-in-progress
+ (when (and doc-dual-view-mode
+ (not doc-dual-view--sync-in-progress))
(let ((doc-dual-view--sync-in-progress t))
(when-let*
((cfg (cdr (assoc major-mode doc-dual-view-modes)))
@@ -107,18 +108,30 @@ by adding entries to this list.")
(doc-dual-view--call-func cfg :goto target-page))))
windows))))))
+(defun doc-dual-view--manage-advice (add-or-remove)
+ "Add or remove advice for all functions in `doc-dual-view-modes`.
+ADD-OR-REMOVE should be either 'add or 'remove."
+ (dolist (mode-entry doc-dual-view-modes)
+ (dolist (action '(:goto :next :prev))
+ (when-let ((func (plist-get (cdr mode-entry) action)))
+ (if (eq add-or-remove 'add)
+ (advice-add func :after #'doc-dual-view--sync-pages)
+ (advice-remove func #'doc-dual-view--sync-pages))))))
+
+(defun doc-dual-view--some-buffer-active-p ()
+ "Return non-nil if some buffer has `doc-dual-view-mode' active."
+ (seq-some (lambda (buf)
+ (buffer-local-value 'doc-dual-view-mode buf))
+ (buffer-list)))
+
;;;###autoload
(define-minor-mode doc-dual-view-mode
"Minor mode to sync pages between two windows showing the same document."
:global nil
- (dolist (mode-entry doc-dual-view-modes)
- (let* ((mode (car mode-entry))
- (mode-config (cdr mode-entry)))
- (dolist (action '(:goto :next :prev))
- (let ((func (plist-get mode-config action)))
- (if doc-dual-view-mode
- (advice-add func :after #'doc-dual-view--sync-pages)
- (advice-remove func #'doc-dual-view--sync-pages)))))))
+ (if doc-dual-view-mode
+ (doc-dual-view--manage-advice 'add)
+ (unless (doc-dual-view--some-buffer-active-p)
+ (doc-dual-view--manage-advice 'remove))))
(defun doc-dual-view--maybe-enable ()
"Enable `doc-dual-view-mode' if appropriate for this buffer."
