[Python-checkins] bpo-41898: add caveat on root logger seeing all messages in assertLogs doc (GH-22526) (GH-22540)

[Miss Skeleton (bot)]

https://github.com/python/cpython/commit/faa8c6a8f1fe9c3bac31061e8a59a686b983ebb8
commit: faa8c6a8f1fe9c3bac31061e8a59a686b983ebb8
branch: 3.9
author: Miss Skeleton (bot) <31488909+miss-islington at users.noreply.github.com>
committer: GitHub <noreply at github.com>
date: 2020-10-04T16:38:03+01:00
summary:

bpo-41898: add caveat on root logger seeing all messages in assertLogs doc (GH-22526) (GH-22540)

(cherry picked from commit 1ed54435268b285964141fb74d47ceaa33ea79ab)

files:
M Doc/library/unittest.rst

diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 285bb9e8cbe62..8a4fd25322e33 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -1088,7 +1088,8 @@ Test cases
 
       If given, *logger* should be a :class:`logging.Logger` object or a
       :class:`str` giving the name of a logger.  The default is the root
-      logger, which will catch all messages.
+      logger, which will catch all messages that were not blocked by a
+      non-propagating descendent logger.
 
       If given, *level* should be either a numeric logging level or
       its string equivalent (for example either ``"ERROR"`` or