diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
index 0f82b29f7494399c93920543ce65bf9258459cd5_bWVyY3VyaWFsL2xvY2FscmVwby5weQ==..c5bcd946a34b77d7680d62ea329542a06d48b5df_bWVyY3VyaWFsL2xvY2FscmVwby5weQ== 100644
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1568,7 +1568,7 @@
             else:
                 raise error.ProgrammingError(
                     b"unsupported changeid '%s' of type %s"
-                    % (changeid, pycompat.sysstr(type(changeid)))
+                    % (changeid, pycompat.bytestr(type(changeid)))
                 )
 
             return context.changectx(self, rev, node)