use getattr_static in spy instead of __getattributes__

src/pytest_mock/plugin.py

@@ -99,20 +99,14 @@ def spy(self, obj: object, name: str) -> unittest.mock.MagicMock:
         :return: Spy object.
         """
         method = getattr(obj, name)
-
-        autospec = inspect.ismethod(method) or inspect.isfunction(method)
-        # Can't use autospec classmethod or staticmethod objects
-        # see: https://bugs.python.org/issue23078
-        if inspect.isclass(obj):
-            # Bypass class descriptor:
-            # http://stackoverflow.com/questions/14187973/python3-check-if-method-is-static
-            try:
-                value = obj.__getattribute__(obj, name)  # type:ignore
-            except AttributeError:
-                pass
-            else:
-                if isinstance(value, (classmethod, staticmethod)):
-                    autospec = False
+        if inspect.isclass(obj) and isinstance(
+            inspect.getattr_static(obj, name), (classmethod, staticmethod)
+        ):
+            # Can't use autospec classmethod or staticmethod objects before 3.7
+            # see: https://bugs.python.org/issue23078
+            autospec = False
+        else:
+            autospec = inspect.ismethod(method) or inspect.isfunction(method)
 
         def wrapper(*args, **kwargs):
             spy_obj.spy_return = None

tests/test_pytest_mock.py

@@ -7,7 +7,7 @@
 from unittest.mock import MagicMock
 
 import pytest
-from pytest_mock import MockerFixture, PytestMockWarning
+from pytest_mock import MockerFixture, PytestMockWarning  # type: ignore
 
 pytest_plugins = "pytester"
 
@@ -162,7 +162,7 @@ def test_mock_patch_dict_resetall(mocker: MockerFixture) -> None:
     ],
 )
 def test_mocker_aliases(name: str, pytestconfig: Any) -> None:
-    from pytest_mock.plugin import _get_mock_module
+    from pytest_mock.plugin import _get_mock_module  # type: ignore
 
     mock_module = _get_mock_module(pytestconfig)
 
@@ -268,6 +268,19 @@ def bar(self, arg):
         assert str(spy.spy_exception) == "Error with {}".format(v)
 
 
+def test_instance_method_spy_autospec_true(mocker: MockerFixture) -> None:
+    class Foo:
+        def bar(self, arg):
+            return arg * 2
+
+    foo = Foo()
+    spy = mocker.spy(foo, "bar")
+    with pytest.raises(
+        AttributeError, match="'function' object has no attribute 'fake_assert_method'"
+    ):
+        spy.fake_assert_method(arg=5)
+
+
 def test_spy_reset(mocker: MockerFixture) -> None:
     class Foo(object):
         def bar(self, x):
@@ -342,6 +355,17 @@ def bar(cls, arg):
     assert spy.spy_return == 20
 
 
+@skip_pypy
+def test_class_method_spy_autospec_false(mocker: MockerFixture) -> None:
+    class Foo:
+        @classmethod
+        def bar(cls, arg):
+            return arg * 2
+
+    spy = mocker.spy(Foo, "bar")
+    spy.fake_assert_method()
+
+
 @skip_pypy
 def test_class_method_subclass_spy(mocker: MockerFixture) -> None:
     class Base: