Fixed #27079 -- Avoided multiple setUpClass()/tearDownClass() calls in LiveServerTestCase tests.

3 files changed, 23 insertions, 54 deletions

diff --git a/django/test/testcases.py b/django/test/testcases.py
index 004925e8f7..e65a466ebd 100644
--- a/django/test/testcases.py
+++ b/django/test/testcases.py
@@ -1533,7 +1533,11 @@ class LiveServerTestCase(TransactionTestCase):
             ALLOWED_HOSTS={'append': cls.allowed_host},
         )
         cls._live_server_modified_settings.enable()
+        cls.addClassCleanup(cls._live_server_modified_settings.disable)
+        cls._start_server_thread()
 
+    @classmethod
+    def _start_server_thread(cls):
         connections_override = cls._make_connections_override()
         for conn in connections_override.values():
             # Explicitly enable thread-shareability for this connection.
@@ -1542,13 +1546,11 @@ class LiveServerTestCase(TransactionTestCase):
         cls.server_thread = cls._create_server_thread(connections_override)
         cls.server_thread.daemon = True
         cls.server_thread.start()
+        cls.addClassCleanup(cls._terminate_thread)
 
         # Wait for the live server to be ready
         cls.server_thread.is_ready.wait()
         if cls.server_thread.error:
-            # Clean up behind ourselves, since tearDownClass won't get called in
-            # case of errors.
-            cls._tearDownClassInternal()
             raise cls.server_thread.error
 
     @classmethod
@@ -1561,20 +1563,13 @@ class LiveServerTestCase(TransactionTestCase):
         )
 
     @classmethod
-    def _tearDownClassInternal(cls):
+    def _terminate_thread(cls):
         # Terminate the live server's thread.
         cls.server_thread.terminate()
         # Restore shared connections' non-shareability.
         for conn in cls.server_thread.connections_override.values():
             conn.dec_thread_sharing()
 
-        cls._live_server_modified_settings.disable()
-        super().tearDownClass()
-
-    @classmethod
-    def tearDownClass(cls):
-        cls._tearDownClassInternal()
-
 
 class SerializeMixin:
     """
diff --git a/tests/servers/tests.py b/tests/servers/tests.py
index cea25b9920..2b2eab20aa 100644
--- a/tests/servers/tests.py
+++ b/tests/servers/tests.py
@@ -127,18 +127,12 @@ class LiveServerTestCaseSetupTest(LiveServerBase):
             super().setUpClass()
         except RuntimeError:
             # LiveServerTestCase's change to ALLOWED_HOSTS should be reverted.
+            cls.doClassCleanups()
             cls.check_allowed_hosts(['testserver'])
         else:
             raise RuntimeError('Server did not fail.')
         cls.set_up_called = True
 
-    @classmethod
-    def tearDownClass(cls):
-        # Make tearDownClass() a no-op because setUpClass() was already cleaned
-        # up, and because the error inside setUpClass() was handled, which will
-        # cause tearDownClass() to be called when it normally wouldn't.
-        pass
-
     def test_set_up_class(self):
         self.assertIs(self.set_up_called, True)
 
@@ -334,7 +328,7 @@ class LiveServerPort(LiveServerBase):
         """
         TestCase = type("TestCase", (LiveServerBase,), {})
         try:
-            TestCase.setUpClass()
+            TestCase._start_server_thread()
         except OSError as e:
             if e.errno == errno.EADDRINUSE:
                 # We're out of ports, LiveServerTestCase correctly fails with
@@ -342,15 +336,12 @@ class LiveServerPort(LiveServerBase):
                 return
             # Unexpected error.
             raise
-        try:
-            # We've acquired a port, ensure our server threads acquired
-            # different addresses.
-            self.assertNotEqual(
-                self.live_server_url, TestCase.live_server_url,
-                "Acquired duplicate server addresses for server threads: %s" % self.live_server_url
-            )
-        finally:
-            TestCase.tearDownClass()
+        self.assertNotEqual(
+            self.live_server_url,
+            TestCase.live_server_url,
+            f'Acquired duplicate server addresses for server threads: '
+            f'{self.live_server_url}',
+        )
 
     def test_specified_port_bind(self):
         """LiveServerTestCase.port customizes the server's port."""
@@ -360,14 +351,13 @@ class LiveServerPort(LiveServerBase):
         s.bind(('', 0))
         TestCase.port = s.getsockname()[1]
         s.close()
-        TestCase.setUpClass()
-        try:
-            self.assertEqual(
-                TestCase.port, TestCase.server_thread.port,
-                'Did not use specified port for LiveServerTestCase thread: %s' % TestCase.port
-            )
-        finally:
-            TestCase.tearDownClass()
+        TestCase._start_server_thread()
+        self.assertEqual(
+            TestCase.port,
+            TestCase.server_thread.port,
+            f'Did not use specified port for LiveServerTestCase thread: '
+            f'{TestCase.port}',
+        )
 
 
 class LiveServerThreadedTests(LiveServerBase):
diff --git a/tests/staticfiles_tests/test_liveserver.py b/tests/staticfiles_tests/test_liveserver.py
index 970121f2da..38d1513c9a 100644
--- a/tests/staticfiles_tests/test_liveserver.py
+++ b/tests/staticfiles_tests/test_liveserver.py
@@ -29,22 +29,8 @@ class LiveServerBase(StaticLiveServerTestCase):
         # Override settings
         cls.settings_override = override_settings(**TEST_SETTINGS)
         cls.settings_override.enable()
-        try:
-            super().setUpClass()
-        except Exception:
-            # Clean up since tearDownClass() isn't called on errors.
-            cls._tearDownLiveServerBase()
-            raise
-
-    @classmethod
-    def _tearDownLiveServerBase(cls):
-        # Restore original settings
-        cls.settings_override.disable()
-
-    @classmethod
-    def tearDownClass(cls):
-        super().tearDownClass()
-        cls._tearDownLiveServerBase()
+        cls.addClassCleanup(cls.settings_override.disable)
+        super().setUpClass()
 
 
 class StaticLiveServerChecks(LiveServerBase):
@@ -74,8 +60,6 @@ class StaticLiveServerChecks(LiveServerBase):
             # app without having set the required STATIC_URL setting.")
             pass
         else:
-            # super().setUpClass() cleans up after itself on a failure.
-            super().tearDownClass()
             raise Exception('setUpClass() should have raised an exception.')
 
     def test_test_test(self):