--- a/mercurial/manifest.py	Sat Aug 10 14:22:26 2024 -0400
+++ b/mercurial/manifest.py	Wed Aug 14 03:25:16 2024 -0400
@@ -534,7 +534,7 @@
             return False
         return key in self._lm
 
-    def __delitem__(self, key: bytes) -> bool:
+    def __delitem__(self, key: bytes) -> None:
         del self._lm[key]
 
     def __iter__(self) -> Iterator[bytes]: