Fix async assertion argument introspection

CHANGELOG.rst

@@ -4,6 +4,9 @@ Releases
 Unreleased
 ----------
 
+* `#611 <https://github.com/pytest-dev/pytest-mock/pull/611>`_: Fixed async mock assertion introspection to use awaited arguments instead of the latest call's arguments.
+
+
 * `#606 <https://github.com/pytest-dev/pytest-mock/pull/606>`_: ``mocker.resetall(return_value=True, side_effect=True)`` now also applies to non-callable mocks, such as those returned by ``mocker.create_autospec(SomeClass, instance=True)``. Previously both arguments were silently ignored for them.
 * `#547 <https://github.com/pytest-dev/pytest-mock/issues/547>`_: Added ``SpyType`` for annotating ``mocker.spy`` results.
 * Dropped support for EOL Python 3.9.

src/pytest_mock/plugin.py

@@ -501,8 +501,13 @@ def assert_wrapper(
         else:
             __mock_self = args[0]
             msg = str(e)
-            if __mock_self.call_args is not None:
-                actual_args, actual_kwargs = __mock_self.call_args
+            call_args = (
+                __mock_self.await_args
+                if "await" in __wrapped_mock_method__.__name__
+                else __mock_self.call_args
+            )
+            if call_args is not None:
+                actual_args, actual_kwargs = call_args
                 introspection = ""
                 try:
                     assert actual_args == args[1:]

tests/test_pytest_mock.py

@@ -820,6 +820,41 @@ def test_assert_has_calls(mocker: MockerFixture) -> None:
         stub.assert_has_calls([mocker.call("bar")])
 
 
+@pytest.mark.usefixtures("needs_assert_rewrite")
+@pytest.mark.parametrize(
+    "assertion", ["assert_awaited_with", "assert_awaited_once_with", "assert_any_await"]
+)
+@pytest.mark.asyncio
+async def test_async_assertion_uses_await_arguments(
+    mocker: MockerFixture, assertion: str
+) -> None:
+    stub = mocker.AsyncMock()
+    await stub("awaited", source="awaited")
+    stub("called", source="called").close()
+
+    getattr(stub, assertion)("awaited", source="awaited")
+    with pytest.raises(AssertionError) as exc_info:
+        getattr(stub, assertion)("wrong", source="wrong")
+    introspection = str(exc_info.value).split("pytest introspection follows:")[1]
+    assert "'awaited'" in introspection
+    assert "'called'" not in introspection
+
+    with pytest.raises(AssertionError) as exc_info:
+        stub.assert_called_with("wrong", source="wrong")
+    introspection = str(exc_info.value).split("pytest introspection follows:")[1]
+    assert "'called'" in introspection
+    assert "'awaited'" not in introspection
+
+
+@pytest.mark.usefixtures("needs_assert_rewrite")
+def test_async_assertion_without_await(mocker: MockerFixture) -> None:
+    stub = mocker.AsyncMock()
+    stub("called").close()
+    with pytest.raises(AssertionError) as exc_info:
+        stub.assert_awaited_with("expected")
+    assert "pytest introspection follows:" not in str(exc_info.value)
+
+
 def test_assert_has_calls_multiple_calls(mocker: MockerFixture) -> None:
     stub = mocker.stub()
     stub("foo")