Method test_bug1001011

Lib/test/string_tests.py:1583–1598

(self)

    # Additional tests that only work with str.

    def test_bug1001011(self):
        # Make sure join returns a NEW object for single item sequences
        # involving a subclass.
        # Make sure that it is of the appropriate type.
        # Check the optimisation still occurs for standard objects.
        t = self.type2test
        class subclass(t):
            pass
        s1 = subclass("abcd")
        s2 = t().join([s1])
        self.assertIsNot(s1, s2)
        self.assertIs(type(s2), t)

        s1 = t("abcd")
        s2 = t().join([s1])
        self.assertIs(s1, s2)