Simplify testing the warning filename (GH-91868)

The context manager result has the "filename" attribute.

3 files changed, 15 insertions, 15 deletions

diff --git a/Lib/unittest/test/test_async_case.py b/Lib/unittest/test/test_async_case.py
index a481408..1b910a4 100644
--- a/Lib/unittest/test/test_async_case.py
+++ b/Lib/unittest/test/test_async_case.py
@@ -259,15 +259,15 @@ class TestAsyncCase(unittest.TestCase):
 
         with self.assertWarns(DeprecationWarning) as w:
             Test('test1').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warnings[0].message))
-        self.assertIn('test1', str(w.warnings[0].message))
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertIn('It is deprecated to return a value!=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.warnings[0].message))
-        self.assertIn('test2', str(w.warnings[0].message))
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        self.assertIn('test2', str(w.warning))
+        self.assertEqual(w.filename, __file__)
 
     def test_cleanups_interleave_order(self):
         events = []
diff --git a/Lib/unittest/test/test_case.py b/Lib/unittest/test/test_case.py
index f6cb997..374a255 100644
--- a/Lib/unittest/test/test_case.py
+++ b/Lib/unittest/test/test_case.py
@@ -316,15 +316,15 @@ class Test_TestCase(unittest.TestCase, TestEquality, TestHashing):
 
         with self.assertWarns(DeprecationWarning) as w:
             Foo('test1').run()
-        self.assertIn('It is deprecated to return a value!=None', str(w.warnings[0].message))
-        self.assertIn('test1', str(w.warnings[0].message))
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertIn('It is deprecated to return a value!=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.warnings[0].message))
-        self.assertIn('test2', str(w.warnings[0].message))
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertIn('It is deprecated to return a value!=None', str(w.warning))
+        self.assertIn('test2', str(w.warning))
+        self.assertEqual(w.filename, __file__)
 
     def _check_call_order__subtests(self, result, events, expected_events):
         class Foo(Test.LoggingTestCase):
diff --git a/Lib/unittest/test/test_loader.py b/Lib/unittest/test/test_loader.py
index 90e2081..de2268c 100644
--- a/Lib/unittest/test/test_loader.py
+++ b/Lib/unittest/test/test_loader.py
@@ -1609,7 +1609,7 @@ class TestObsoleteFunctions(unittest.TestCase):
             tests = unittest.getTestCaseNames(self.MyTestCase,
                 prefix='check', sortUsing=self.reverse_three_way_cmp,
                 testNamePatterns=None)
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertEqual(w.filename, __file__)
         self.assertEqual(tests, ['check_2', 'check_1'])
 
     def test_makeSuite(self):
@@ -1617,7 +1617,7 @@ class TestObsoleteFunctions(unittest.TestCase):
             suite = unittest.makeSuite(self.MyTestCase,
                     prefix='check', sortUsing=self.reverse_three_way_cmp,
                     suiteClass=self.MyTestSuite)
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertEqual(w.filename, __file__)
         self.assertIsInstance(suite, self.MyTestSuite)
         expected = self.MyTestSuite([self.MyTestCase('check_2'),
                                      self.MyTestCase('check_1')])
@@ -1631,7 +1631,7 @@ class TestObsoleteFunctions(unittest.TestCase):
             suite = unittest.findTestCases(m,
                 prefix='check', sortUsing=self.reverse_three_way_cmp,
                 suiteClass=self.MyTestSuite)
-        self.assertEqual(w.warnings[0].filename, __file__)
+        self.assertEqual(w.filename, __file__)
         self.assertIsInstance(suite, self.MyTestSuite)
         expected = [self.MyTestSuite([self.MyTestCase('check_2'),
                                       self.MyTestCase('check_1')])]