--- a/mercurial/shelve.py	Wed Jul 24 18:10:50 2019 +0530
+++ b/mercurial/shelve.py	Wed Jul 24 18:20:01 2019 +0530
@@ -836,8 +836,8 @@
     snode = repo.commit(text=shelvectx.description(),
                         extra=shelvectx.extra(),
                         user=shelvectx.user())
-    m = scmutil.matchfiles(repo, repo[snode].files())
     if snode:
+        m = scmutil.matchfiles(repo, repo[snode].files())
         _shelvecreatedcommit(repo, snode, basename, m)
 
     return newnode, bool(snode)