gh-97837: Change deprecation warning message in `unittest` (#97838)

2 files changed, 28 insertions, 6 deletions

diff --git a/Lib/test/test_unittest/test_async_case.py b/Lib/test/test_unittest/test_async_case.py
index d7d4dc9..fab8270 100644
--- a/Lib/test/test_unittest/test_async_case.py
+++ b/Lib/test/test_unittest/test_async_case.py
@@ -277,25 +277,36 @@ class TestAsyncCase(unittest.TestCase):
         self.assertEqual(events, ['asyncSetUp', 'test', 'asyncTearDown', 'cleanup2', 'cleanup1'])
 
     def test_deprecation_of_return_val_from_test(self):
-        # Issue 41322 - deprecate return of value!=None from a test
+        # Issue 41322 - deprecate return of value that is not None from a test
+        class Nothing:
+            def __eq__(self, o):
+                return o is None
         class Test(unittest.IsolatedAsyncioTestCase):
             async def test1(self):
                 return 1
             async def test2(self):
                 yield 1
+            async def test3(self):
+                return Nothing()
 
         with self.assertWarns(DeprecationWarning) as w:
             Test('test1').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        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__)
 
         with self.assertWarns(DeprecationWarning) as w:
             Test('test2').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        self.assertIn('It is deprecated to return a value that is not None', str(w.warning))
         self.assertIn('test2', str(w.warning))
         self.assertEqual(w.filename, __file__)
 
+        with self.assertWarns(DeprecationWarning) as w:
+            Test('test3').run()
+        self.assertIn('It is deprecated to return a value that is not None', str(w.warning))
+        self.assertIn('test3', str(w.warning))
+        self.assertEqual(w.filename, __file__)
+
     def test_cleanups_interleave_order(self):
         events = []
 
diff --git a/Lib/test/test_unittest/test_case.py b/Lib/test/test_unittest/test_case.py
index fae0d10..05d60a8 100644
--- a/Lib/test/test_unittest/test_case.py
+++ b/Lib/test/test_unittest/test_case.py
@@ -307,25 +307,36 @@ class Test_TestCase(unittest.TestCase, TestEquality, TestHashing):
         Foo('test').run()
 
     def test_deprecation_of_return_val_from_test(self):
-        # Issue 41322 - deprecate return of value!=None from a test
+        # Issue 41322 - deprecate return of value that is not None from a test
+        class Nothing:
+            def __eq__(self, o):
+                return o is None
         class Foo(unittest.TestCase):
             def test1(self):
                 return 1
             def test2(self):
                 yield 1
+            def test3(self):
+                return Nothing()
 
         with self.assertWarns(DeprecationWarning) as w:
             Foo('test1').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        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__)
 
         with self.assertWarns(DeprecationWarning) as w:
             Foo('test2').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        self.assertIn('It is deprecated to return a value that is not None', str(w.warning))
         self.assertIn('test2', str(w.warning))
         self.assertEqual(w.filename, __file__)
 
+        with self.assertWarns(DeprecationWarning) as w:
+            Foo('test3').run()
+        self.assertIn('It is deprecated to return a value that is not None', str(w.warning))
+        self.assertIn('test3', str(w.warning))
+        self.assertEqual(w.filename, __file__)
+
     def _check_call_order__subtests(self, result, events, expected_events):
         class Foo(Test.LoggingTestCase):
             def test(self):