diff -r 1726a53a8494 -r dfca84970da8 mercurial/mergeutil.py
--- a/mercurial/mergeutil.py	Fri Jan 15 01:20:47 2021 +0100
+++ b/mercurial/mergeutil.py	Mon May 18 17:29:53 2020 -0400
@@ -13,7 +13,7 @@
 
 
 def checkunresolved(ms):
-    if list(ms.unresolved()):
+    if ms.unresolvedcount():
         raise error.StateError(
             _(b"unresolved merge conflicts (see 'hg help resolve')")
         )