bpo-37251: MagicMock with function spec used as a spec in mock.patch should return a MagicMock

Lib/unittest/mock.py

@@ -46,7 +46,8 @@
 _safe_super = super
 
 def _is_async_obj(obj):
- if getattr(obj, '__code__', None):
+ code = getattr(obj, '__code__', None)
+ if isinstance(code, CodeType):
  return asyncio.iscoroutinefunction(obj) or inspect.isawaitable(obj)
  else:
  return False

Lib/unittest/test/testmock/testasync.py

@@ -321,6 +321,13 @@ def test_is_child_AsyncMock(self):
  self.assertIsInstance(mock.normal_method, MagicMock)
  self.assertIsInstance(mock, MagicMock)
 
+ def test_magicmock_lambda_spec(self):
+ mock_obj = MagicMock()
+ mock_obj.mock_func = MagicMock(spec=lambda x: x)
+
+ with patch.object(mock_obj, "mock_func") as cm:
+ self.assertIsInstance(cm, MagicMock)
+
 
 class AsyncArguments(unittest.TestCase):
  def test_add_return_value(self):

Misc/NEWS.d/next/Library/2019-06-15-21-52-23.bpo-37251.dYzQt6.rst

@@ -0,0 +1,3 @@
+:class:`unittest.mock.MagicMock` with function as spec used as a spec to
+:func:`unittest.mock.patch` should return a
+:class:`unittest.mock.MagicMock`. Patch by Karthikeyan Singaravelan.