Method deep_nested_struct

Lib/test/pickletester.py:4597–4620

(self, create_nested,
                           minprotocol=0, compare_equal=True,
                           depth=FAST_NESTING_LIMIT * 2)

        self.fast_save_enter(lambda i: {"key": i})

    def deep_nested_struct(self, create_nested,
                           minprotocol=0, compare_equal=True,
                           depth=FAST_NESTING_LIMIT * 2):
        # gh-146059: Check that fast_save_leave() is called when
        # fast_save_enter() is called.
        if not hasattr(self, "pickler"):
            self.skipTest("need Pickler class")

        data = None
        for i in range(depth):
            data = create_nested(data)
        protocols = range(minprotocol, pickle.HIGHEST_PROTOCOL + 1)
        for proto in protocols:
            with self.subTest(proto=proto):
                buf = io.BytesIO()
                pickler = self.pickler(buf, protocol=proto)
                # Enable fast mode (disables memo, enables cycle detection)
                pickler.fast = 1
                pickler.dump(data)

                buf.seek(0)
                data2 = self.unpickler(buf).load()
                if compare_equal:
                    self.assertEqual(data2, data)

    def test_deep_nested_struct_tuple(self):
        self.deep_nested_struct(lambda data: (data,))