vc-revert: Offer to save modified buffers (bug#55310)

* lisp/vc/vc.el (vc-revert): Offer to save modified buffers that
otherwise prevent proceeding with the revert (bug#55310).

(cherry picked from commit 6f483ffdc217ea9f8dc079b2344f771214222273)

diff --git a/lisp/vc/vc.el b/lisp/vc/vc.el
index a2bd24a20427a64b324f83667990e6cd5ac87f98..dba487aa0a7b21bc4c64126f736a9a6465a8f9ae 100644 (file)
--- a/lisp/vc/vc.el
+++ b/lisp/vc/vc.el
@@ -3241,14 +3241,21 @@ to the working revision (except for keyword expansion)."
     ;; show the changes and ask for confirmation to discard them.
     (when (or (not files) (memq (buffer-file-name) files))
       (vc-buffer-sync nil))
-    (dolist (file files)
-      (let ((buf (get-file-buffer file)))
-       (when (and buf (buffer-modified-p buf))
-         (error "Please kill or save all modified buffers before reverting")))
-      (when (vc-up-to-date-p file)
-       (if (yes-or-no-p (format "%s seems up-to-date.  Revert anyway? " file))
-           (setq queried t)
-         (error "Revert canceled"))))
+    (save-some-buffers nil (lambda ()
+                             (member (buffer-file-name) files)))
+    (let (needs-save)
+      (dolist (file files)
+        (let ((buf (get-file-buffer file)))
+         (when (and buf (buffer-modified-p buf))
+            (push buf needs-save)))
+        (when (vc-up-to-date-p file)
+         (if (yes-or-no-p (format "%s seems up-to-date.  Revert anyway? "
+                                   file))
+             (setq queried t)
+           (error "Revert canceled"))))
+      (when needs-save
+        (error "Cannot revert with these buffers unsaved: %s"
+               (string-join (mapcar #'buffer-name needs-save) ", "))))
     (unwind-protect
        (when (if vc-revert-show-diff
                  (progn