gh-111388: Add `show_group` parameter to `traceback.format_exception_only` (#111390)

1 files changed, 8 insertions, 1 deletions

diff --git a/Doc/library/traceback.rst b/Doc/library/traceback.rst
index 67ee73d..408da7f 100644
--- a/Doc/library/traceback.rst
+++ b/Doc/library/traceback.rst
@@ -135,7 +135,7 @@ The module defines the following functions:
    text line is not ``None``.
 
 
-.. function:: format_exception_only(exc, /[, value])
+.. function:: format_exception_only(exc, /[, value], *, show_group=False)
 
    Format the exception part of a traceback using an exception value such as
    given by ``sys.last_value``.  The return value is a list of strings, each
@@ -149,6 +149,10 @@ The module defines the following functions:
    can be passed as the first argument.  If *value* is provided, the first
    argument is ignored in order to provide backwards compatibility.
 
+   When *show_group* is ``True``, and the exception is an instance of
+   :exc:`BaseExceptionGroup`, the nested exceptions are included as
+   well, recursively, with indentation relative to their nesting depth.
+
    .. versionchanged:: 3.10
       The *etype* parameter has been renamed to *exc* and is now
       positional-only.
@@ -156,6 +160,9 @@ The module defines the following functions:
    .. versionchanged:: 3.11
       The returned list now includes any notes attached to the exception.
 
+   .. versionchanged:: 3.13
+      *show_group* parameter was added.
+
 
 .. function:: format_exception(exc, /[, value, tb], limit=None, chain=True)