Method checkraises

Lib/test/string_tests.py:78–85

(self, exc, obj, methodname, *args, expected_msg=None)

    # check that obj.method(*args) raises exc
    def checkraises(self, exc, obj, methodname, *args, expected_msg=None):
        obj = self.fixtype(obj)
        args = self.fixtype(args)
        with self.assertRaises(exc) as cm:
            getattr(obj, methodname)(*args)
        self.assertNotEqual(str(cm.exception), '')
        if expected_msg is not None:
            self.assertEqual(str(cm.exception), expected_msg)

    # call obj.method(*args) without any checks
    def checkcall(self, obj, methodname, *args):