From 2f1487ee7d5d0bdca6af943abf0db67e8489e008 Mon Sep 17 00:00:00 2001
From: cananoo <2059997196@qq.com>
Date: Thu, 27 Aug 2026 20:56:50 +0800
Subject: [PATCH 1/2] gh-156460: Await async callable side effects in AsyncMock

---
 Lib/test/test_unittest/testmock/testasync.py             | 9 +++++++++
 Lib/unittest/mock.py                                     | 3 ++-
 .../2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst       | 1 +
 3 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst

diff --git a/Lib/test/test_unittest/testmock/testasync.py b/Lib/test/test_unittest/testmock/testasync.py
index f96aef7325ff4c..02d8e273436a4b 100644
--- a/Lib/test/test_unittest/testmock/testasync.py
+++ b/Lib/test/test_unittest/testmock/testasync.py
@@ -468,6 +468,15 @@ async def addition(var):
         result = await mock(5)
         self.assertEqual(result, 6)
 
+    async def test_add_side_effect_async_callable(self):
+        class AsyncCallable:
+            async def __call__(self, var):
+                return var + 1
+
+        mock = AsyncMock(side_effect=AsyncCallable())
+        result = await mock(5)
+        self.assertEqual(result, 6)
+
     async def test_add_side_effect_normal_function(self):
         def addition(var):
             return var + 1
diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index d0ca94668e05bc..3aab147f187cc6 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -2331,7 +2331,8 @@ async def _execute_mock_call(self, /, *args, **kwargs):
                     raise StopAsyncIteration
                 if _is_exception(result):
                     raise result
-            elif iscoroutinefunction(effect):
+            elif (iscoroutinefunction(effect) or
+                  iscoroutinefunction(getattr(effect, '__call__', None))):
                 result = await effect(*args, **kwargs)
             else:
                 result = effect(*args, **kwargs)
diff --git a/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst b/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst
new file mode 100644
index 00000000000000..e8845f566ca21c
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst
@@ -0,0 +1 @@
+Await async callable objects used as :attr:`unittest.mock.AsyncMock.side_effect`.

From c7fcd7d43413714cf6727f59c51331ee0ffff794 Mon Sep 17 00:00:00 2001
From: cananoo <2059997196@qq.com>
Date: Thu, 27 Aug 2026 21:11:41 +0800
Subject: [PATCH 2/2] Fix NEWS reference for AsyncMock side_effect

---
 .../Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst     | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst b/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst
index e8845f566ca21c..f6871145236ba5 100644
--- a/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst
+++ b/Misc/NEWS.d/next/Library/2026-08-27-20-47-01.gh-issue-156460.A7kP3m.rst
@@ -1 +1,2 @@
-Await async callable objects used as :attr:`unittest.mock.AsyncMock.side_effect`.
+Await async callable objects used as the ``side_effect`` of
+:class:`unittest.mock.AsyncMock`.