bpo-36743: __get__ is sometimes called without the owner argument (#12992)

3 files changed, 5 insertions, 5 deletions

diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index 1b24ef9..0d3f974 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -283,7 +283,7 @@ except AttributeError:
 class DocDescriptor:
     """Helper for builtins.open.__doc__
     """
-    def __get__(self, obj, typ):
+    def __get__(self, obj, typ=None):
         return (
             "open(file, mode='r', buffering=-1, encoding=None, "
                  "errors=None, newline=None, closefd=True)\n\n" +
diff --git a/Lib/functools.py b/Lib/functools.py
index 9495fbe..f87d9c5 100644
--- a/Lib/functools.py
+++ b/Lib/functools.py
@@ -383,7 +383,7 @@ class partialmethod(object):
         _method._partialmethod = self
         return _method
 
-    def __get__(self, obj, cls):
+    def __get__(self, obj, cls=None):
         get = getattr(self.func, "__get__", None)
         result = None
         if get is not None:
@@ -888,7 +888,7 @@ class singledispatchmethod:
         """
         return self.dispatcher.register(cls, func=method)
 
-    def __get__(self, obj, cls):
+    def __get__(self, obj, cls=None):
         def _method(*args, **kwargs):
             method = self.dispatcher.dispatch(args[0].__class__)
             return method.__get__(obj, cls)(*args, **kwargs)
@@ -926,7 +926,7 @@ class cached_property:
                 f"({self.attrname!r} and {name!r})."
             )
 
-    def __get__(self, instance, owner):
+    def __get__(self, instance, owner=None):
         if instance is None:
             return self
         if self.attrname is None:
diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index c6771ce..89312f1 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -2804,7 +2804,7 @@ class PropertyMock(Mock):
     def _get_child_mock(self, /, **kwargs):
         return MagicMock(**kwargs)
 
-    def __get__(self, obj, obj_type):
+    def __get__(self, obj, obj_type=None):
         return self()
     def __set__(self, obj, val):
         self(val)