WIP: first stake at running stdli asyncio unittests again

Author: RonnyPfannschmidt

src/_pytest/python.py

@@ -175,14 +175,26 @@ def async_warn(nodeid: str) -> None:
 @hookimpl(trylast=True)
 def pytest_pyfunc_call(pyfuncitem: "Function"):
     testfunction = pyfuncitem.obj
-    if iscoroutinefunction(testfunction) or (
-        sys.version_info >= (3, 6) and inspect.isasyncgenfunction(testfunction)
-    ):
+
+    try:
+        # ignoring type as the import is  invalid in py37  and mypy thinks its a error
+        from unittest import IsolatedAsyncioTestCase  # type: ignore
+    except ImportError:
+        async_ok_in_stdlib = False
+    else:
+        async_ok_in_stdlib = isinstance(testfunction.__self__, IsolatedAsyncioTestCase)
+
+    if (
+        iscoroutinefunction(testfunction)
+        or (sys.version_info >= (3, 6) and inspect.isasyncgenfunction(testfunction))
+    ) and not async_ok_in_stdlib:
         async_warn(pyfuncitem.nodeid)
     funcargs = pyfuncitem.funcargs
     testargs = {arg: funcargs[arg] for arg in pyfuncitem._fixtureinfo.argnames}
     result = testfunction(**testargs)
-    if hasattr(result, "__await__") or hasattr(result, "__aiter__"):
+    if (
+        hasattr(result, "__await__") or hasattr(result, "__aiter__")
+    ) and not async_ok_in_stdlib:
         async_warn(pyfuncitem.nodeid)
     return True
 

testing/example_scripts/pytest.ini

@@ -0,0 +1 @@
+[pytest]

testing/example_scripts/unittest/test_unittest_asyncio.py

@@ -0,0 +1,15 @@
+from unittest import IsolatedAsyncioTestCase  # type: ignore
+
+
+class AsyncArguments(IsolatedAsyncioTestCase):
+    async def test_something_async(self):
+        async def addition(x, y):
+            return x + y
+
+        self.assertEqual(await addition(2, 2), 4)
+
+    async def test_something_async_fails(self):
+        async def addition(x, y):
+            return x + y
+
+        self.assertEqual(await addition(2, 2), 3)