gh-65453: Docs - clarify AttributeError behaviour on PropertyMock (GH-121666)

Fixed at EuroPython 24 sprints.

diff --git a/Doc/library/unittest.mock.rst b/Doc/library/unittest.mock.rst
index 01206e05f4ba01168dd0b0a7bcc05744d4fe9726..757277e102d80e7b62984e41e05c52b06e02c0c8 100644 (file)
--- a/Doc/library/unittest.mock.rst
+++ b/Doc/library/unittest.mock.rst
@@ -860,6 +860,20 @@ object::
     3
     >>> p.assert_called_once_with()
 
+.. caution::
+
+    If an :exc:`AttributeError` is raised by :class:`PropertyMock`,
+    it will be interpreted as a missing descriptor and
+    :meth:`~object.__getattr__` will be called on the parent mock::
+
+        >>> m = MagicMock()
+        >>> no_attribute = PropertyMock(side_effect=AttributeError)
+        >>> type(m).my_property = no_attribute
+        >>> m.my_property
+        <MagicMock name='mock.my_property' id='140165240345424'>
+
+    See :meth:`~object.__getattr__` for details.
+
 
 .. class:: AsyncMock(spec=None, side_effect=None, return_value=DEFAULT, wraps=None, name=None, spec_set=None, unsafe=False, **kwargs)