bpo-34844: logging.Formatter enhancement - Ensure style and format string matches in logging.Formatter (GH-9703)

2 files changed, 9 insertions, 0 deletions

diff --git a/Doc/library/logging.config.rst b/Doc/library/logging.config.rst
index de805eb..7f6c3c6 100644
--- a/Doc/library/logging.config.rst
+++ b/Doc/library/logging.config.rst
@@ -226,6 +226,11 @@ otherwise, the context is used to determine what to instantiate.
   (with defaults of ``None``) and these are used to construct a
   :class:`~logging.Formatter` instance.
 
+  .. versionchanged:: 3.8
+     a ``validate`` key (with default of ``True``) can be added into
+     the ``formatters`` section of the configuring dict, this is to
+     validate the format.
+
 * *filters* - the corresponding value will be a dict in which each key
   is a filter id and each value is a dict describing how to configure
   the corresponding Filter instance.
diff --git a/Doc/library/logging.rst b/Doc/library/logging.rst
index c63ea21..71a46ac 100644
--- a/Doc/library/logging.rst
+++ b/Doc/library/logging.rst
@@ -544,6 +544,10 @@ The useful mapping keys in a :class:`LogRecord` are given in the section on
    .. versionchanged:: 3.2
       The *style* parameter was added.
 
+   .. versionchanged:: 3.8
+      The *validate* parameter was added. Incorrect or mismatched style and fmt
+      will raise a ``ValueError``.
+      For example: ``logging.Formatter('%(asctime)s - %(message)s', style='{')``.
 
    .. method:: format(record)