--- a/mercurial/shelve.py	Tue Oct 04 10:24:56 2022 +0200
+++ b/mercurial/shelve.py	Tue Oct 04 14:33:31 2022 +0200
@@ -378,7 +378,7 @@
 def _aborttransaction(repo, tr):
     """Abort current transaction for shelve/unshelve, but keep dirstate"""
     dirstatebackupname = b'dirstate.shelve'
-    repo.dirstate.savebackup(tr, dirstatebackupname)
+    repo.dirstate.savebackup(None, dirstatebackupname)
     tr.abort()
     repo.dirstate.restorebackup(None, dirstatebackupname)