gh-136442: Fix unittest to return exit code 5 when setUpClass raises an exception

Lib/test/test_unittest/test_program.py

@@ -75,6 +75,14 @@ def testUnexpectedSuccess(self):
     class Empty(unittest.TestCase):
         pass
 
+    class SetUpClassFailure(unittest.TestCase):
+        @classmethod
+        def setUpClass(cls):
+            super().setUpClass()
+            raise Exception
+        def testPass(self):
+            pass
+
     class TestLoader(unittest.TestLoader):
         """Test loader that returns a suite containing the supplied testcase."""
 
@@ -191,6 +199,18 @@ def test_ExitEmptySuite(self):
         out = stream.getvalue()
         self.assertIn('\nNO TESTS RAN\n', out)
 
+    def test_ExitSetUpClassFailureSuite(self):
+        stream = BufferedWriter()
+        with self.assertRaises(SystemExit) as cm:
+            unittest.main(
+                argv=["setup_class_failure"],
+                testRunner=unittest.TextTestRunner(stream=stream),
+                testLoader=self.TestLoader(self.SetUpClassFailure))
+        self.assertEqual(cm.exception.code, 1)
+        out = stream.getvalue()
+        self.assertIn('\nERROR: setUpClass (test.test_unittest.test_program.'
+                      'Test_TestProgram.SetUpClassFailure)\n', out)
+
 
 class InitialisableProgram(unittest.TestProgram):
     exit = False

Lib/test/test_unittest/test_setups.py

@@ -47,6 +47,26 @@ def test_two(self):
         self.assertEqual(result.testsRun, 2)
         self.assertEqual(len(result.errors), 0)
 
+    def test_setup_class_raising_error(self):
+        class Test(unittest.TestCase):
+            setUpCalled = 0
+            @classmethod
+            def setUpClass(cls):
+                Test.setUpCalled += 1
+                unittest.TestCase.setUpClass()
+                raise Exception
+            def test_one(self):
+                pass
+            def test_two(self):
+                pass
+
+        result = self.runTests(Test)
+
+        self.assertEqual(Test.setUpCalled, 1)
+        self.assertEqual(result.testsRun, 0)
+        self.assertEqual(len(result.errors), 1)
+        self.assertEqual(len(result.skipped), 0)
+
     def test_teardown_class(self):
         class Test(unittest.TestCase):
             tearDownCalled = 0

Lib/unittest/main.py

@@ -269,12 +269,12 @@ def runTests(self):
             testRunner = self.testRunner
         self.result = testRunner.run(self.test)
         if self.exit:
-            if self.result.testsRun == 0 and len(self.result.skipped) == 0:
+            if not self.result.wasSuccessful():
+                sys.exit(1)
+            elif self.result.testsRun == 0 and len(self.result.skipped) == 0:
                 sys.exit(_NO_TESTS_EXITCODE)
-            elif self.result.wasSuccessful():
-                sys.exit(0)
             else:
-                sys.exit(1)
+                sys.exit(0)
 
 
 main = TestProgram

Misc/NEWS.d/next/Tests/2025-07-09-21-45-51.gh-issue-136442.jlbklP.rst

@@ -0,0 +1 @@
+unittest runner: Don't exit 5 if setUpClass raises an exception