check for multiple warnings in async def unittest

Author: graingert

Lib/test/test_unittest/test_case.py

@@ -20,6 +20,7 @@
     ResultWithNoStartTestRunStopTestRun
 )
 from test.support import captured_stderr, gc_collect
+from test.support.warnings_helper import check_warnings
 
 
 log_foo = logging.getLogger('foo')
@@ -346,15 +347,21 @@ class Foo(unittest.TestCase):
             async def test1(self):
                 return 1
 
-        with self.assertWarns(DeprecationWarning) as w:
+        with check_warnings(
+            (r"coroutine .* was never awaited", RuntimeWarning),
+            (r"It is deprecated to return a value that is not None", DeprecationWarning),
+        ) as recorder:
             Foo('test1').run()
-        self.assertIn('It is deprecated to return a value that is not None', str(w.warning))
-        self.assertIn('test1', str(w.warning))
-        self.assertEqual(w.filename, __file__)
-        self.assertIn("returned 'coroutine'", str(w.warning))
+        w = recorder.warnings[0]
+        warning = w.message
+        filename = w.filename
+        self.assertIn('It is deprecated to return a value that is not None', str(warning))
+        self.assertIn('test1', str(warning))
+        self.assertEqual(filename, __file__)
+        self.assertIn("returned 'coroutine'", str(warning))
         self.assertIn(
             'Maybe you forgot to use IsolatedAsyncioTestCase as the base class?',
-            str(w.warning),
+            str(warning),
         )
 
     def _check_call_order__subtests(self, result, events, expected_events):