1 files changed, 2 insertions, 0 deletions
diff --git a/Misc/NEWS b/Misc/NEWS
index c3fc686..43fcfa4 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -36,6 +36,8 @@ Core and Builtins
 Library
 -------
 
+- Issue #15323: improve failure message of Mock.assert_called_once_with
+
 - Issue #16064: unittest -m claims executable is "python", not "python3"
 
 - Issue #12376: Pass on parameters in TextTestResult.__init__ super call