测试名称如何影响Unittest中测试之间的变量持久性？

Question

How do I persist changes made within the same object inheriting from TestCase in unitttest? I've referred to Persist variable changes between tests in unittest? . And the following codes works well.

from unittest import TestCase, main as unittest_main

    class TestSimpleFoo(TestCase):

        def setUp(self):
            pass

        def test_a(self):
            TestSimpleFoo.foo = 'can'

        def test_f(self):
            self.assertEqual(TestSimpleFoo.foo, 'can')

    if __name__ == '__main__':
        unittest_main()

However, If I change the test name "test_a" to "test_u", the code will be failed. Anyone can tell how could this happen? thanks.

Answer 1

Resolved. I ignored the case execution order

Answer 2

As you already noticed, the execution order is important here. But, in fact, the deeper problem is, that your tests are not independent from each other. Ideally, each test behaves like a complete program of its own, starting from a defined clean starting state, and cleaning up after execution.