import unittest

GLOBAL = []

def f(n):
    global GLOBAL
    GLOBAL.append(n)
    raise Exception


class TestSubTestResult(unittest.TestResult):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.addSubTestCalls = []

    def addSubTest(self, test, subtest, outcome):
        self.addSubTestCalls.append((subtest._message, list(GLOBAL)))
    

class TestSubTest(unittest.TestCase):

    def runTest(self):
        class TestSubTestInner(unittest.TestCase):
            def runTest(self):
                with self.subTest('1'):
                    f(1)
                with self.subTest('2'):
                    f(2)
        
        result = TestSubTestInner().run(TestSubTestResult())
        self.assertEqual(
            result.addSubTestCalls,
            [
                ('1', [1]),
                ('2', [1, 2]),
            ],
        )

if __name__ == '__main__':
    unittest.main()