test_warnings.py 文件源码

def test_mutate_filter_list(self):
        class X:
            def match(self, a):
                L[:] = []

        L = [("default",X(),UserWarning,X(),0) for i in range(2)]
        with original_warnings.catch_warnings(record=True,
                module=self.module) as w:
            self.module.filters = L
            self.module.warn_explicit(UserWarning("b"), None, "f.py", 42)
            self.assertEqual(str(w[-1].message), "b")