um--extract-tags : save-excursion and find-file-noselect to fix moving point and window

um.el

@@ -277,8 +277,9 @@ Ultimately this relies on `xref-matches-in-files', which calls
 (defun um--extract-tags (files)
   (let ((tags))
     (dolist (f files)
-      (with-temp-buffer
-        (find-file f)
+      (with-current-buffer
+          (find-file-noselect f t)
+        (save-excursion
           (goto-char (point-min))
           (let* ((bound (save-excursion (search-forward "\n\n")))
                  (found t))
@@ -286,7 +287,7 @@ Ultimately this relies on `xref-matches-in-files', which calls
               (setq found (search-forward-regexp um-tag-regexp bound t))
               (when found (add-to-list 'tags (buffer-substring-no-properties
                                               (match-beginning 1) (match-end 1))))
-            ))))
+              )))))
     (reverse tags)))
 
 (defun um-tag-insert (tag)
@@ -344,17 +345,15 @@ Negative prefix arg is handled by `um-tag-do', which see.
          (completions-sort (if insert completions-sort nil))
          (vertico-sort-function (if insert vertico-sort-function nil))
          (tag (completing-read prompt collection nil nil nil
-                               'um-tags-history))
-         ;; TODO: save-excursion is not working around the dolist. why?
-         (buf (current-buffer)))
+                               'um-tags-history)))
 
     (dolist (f files)
-      (save-excursion
+      (with-current-buffer
           ;; TODO: this should use the fallback logic:
-        (find-file (expand-file-name f (um-root-path)))
+          (find-file-noselect (expand-file-name f (um-root-path)) t)
+        (save-excursion
           (um-tag-do tag ARG)
-        (save-buffer)))
-    (switch-to-buffer buf)
+          (save-buffer))))
     ))
 
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