[elpa] externals/denote 3b62f8e167 043/355: Implement denote-link-clear-stale-backlinks

[ELPA Syncer]

branch: externals/denote
commit 3b62f8e167f3b0f4d57cffc91f99bcab24103cf0
Author: Protesilaos Stavrou <info@protesilaos.com>
Commit: Protesilaos Stavrou <info@protesilaos.com>

    Implement denote-link-clear-stale-backlinks
---
 denote-link.el | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/denote-link.el b/denote-link.el
index c0875cf463..4c2674aac6 100644
--- a/denote-link.el
+++ b/denote-link.el
@@ -66,7 +66,10 @@ Both are supplied by `denote-link'."
   "Format of Org link to note.")
 
 (defconst denote-link--backlink-format "[[denote:%s][backlink: %s (%s)]]"
-  "Format of Org link to note.")
+  "Format of Org backlink to note.")
+
+(defconst denote-link--backlink-regexp "\\[\\[denote:\\(.*?\\)\\]\\[backlink: 
\\(.*?\\) (\\(.*?\\))\\]\\]"
+  "Regexp of `denote-link--backlink-format'.")
 
 (defun denote-link--retrieve-value (note regexp)
   "Return REGEXP value from NOTE."
@@ -100,9 +103,6 @@ Run `denote-link-insert-functions' afterwards."
     (insert target-link)
     (run-hook-with-args 'denote-link-insert-functions target origin-link)))
 
-;; TODO 2022-06-07: have a `denote-unlink' command or a
-;; `denote-clean-backlinks' for invalid links.
-
 (defconst denote-link-backlink-heading "Denote backlinks"
   "String of the backlink's heading.
 This heading is appended to a file when another links to it.")
@@ -125,5 +125,16 @@ This heading is appended to a file when another links to 
it.")
           (delete-duplicate-lines heading-point (point-max) nil nil t)
         (widen)))))
 
+(defun denote-link-clear-stale-backlinks ()
+  "Delete backlinks that no longer point to files."
+  (interactive)
+  (let ((default-directory (denote--directory)))
+    (save-excursion
+      (goto-char (point-min))
+      (when (re-search-forward denote-link-backlink-heading nil t))
+      (while (re-search-forward denote-link--backlink-regexp nil t)
+        (unless (file-exists-p (match-string-no-properties 1))
+          (delete-line))))))
+
 (provide 'denote-link)
 ;;; denote-link.el ends here