From: =?utf-8?q?Lum=C3=ADr_=27Frenzy=27_Balhar?= Date: Fri, 11 Oct 2024 17:47:37 +0200 Subject: Accommodate class state restoration for Python 3.13 (#534) Co-authored-by: Olivier Grisel Co-authored-by: Pierre Glaser Origin: backport, https://github.com/cloudpipe/cloudpickle/commit/b3bac2c3aaecf682a6a0099b26370b2ff12c530b Last-Update: 2025-01-25 --- srsly/cloudpickle/cloudpickle.py | 11 +++++++++++ srsly/tests/cloudpickle/cloudpickle_test.py | 25 ++++++++++++++++++++++++- 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/srsly/cloudpickle/cloudpickle.py b/srsly/cloudpickle/cloudpickle.py index 317be69..2697090 100644 --- a/srsly/cloudpickle/cloudpickle.py +++ b/srsly/cloudpickle/cloudpickle.py @@ -842,6 +842,17 @@ def _rehydrate_skeleton_class(skeleton_class, class_dict): registry = attr else: setattr(skeleton_class, attrname, attr) + + if sys.version_info >= (3, 13) and "__firstlineno__" in class_dict: + # Set the Python 3.13+ only __firstlineno__ attribute one more time, as it + # will be automatically deleted by the `setattr(obj, attrname, attr)` call + # above when `attrname` is "__firstlineno__". We assume that preserving this + # information might be important for some users and that it not stale in the + # context of cloudpickle usage, hence legitimate to propagate. Furthermore it + # is necessary to do so to keep deterministic chained pickling as tested in + # test_deterministic_str_interning_for_chained_dynamic_class_pickling. + skeleton_class.__firstlineno__ = class_dict["__firstlineno__"] + if registry is not None: for subclass in registry: skeleton_class.register(subclass) diff --git a/srsly/tests/cloudpickle/cloudpickle_test.py b/srsly/tests/cloudpickle/cloudpickle_test.py index e4dba00..3aead77 100644 --- a/srsly/tests/cloudpickle/cloudpickle_test.py +++ b/srsly/tests/cloudpickle/cloudpickle_test.py @@ -112,7 +112,12 @@ def test_extract_class_dict(): return "c" clsdict = _extract_class_dict(C) - assert sorted(clsdict.keys()) == ["C_CONSTANT", "__doc__", "method_c"] + expected_keys = ["C_CONSTANT", "__doc__", "method_c"] + # New attribute in Python 3.13 beta 1 + # https://github.com/python/cpython/pull/118475 + if sys.version_info >= (3, 13): + expected_keys.insert(2, "__firstlineno__") + assert sorted(clsdict.keys()) == expected_keys assert clsdict["C_CONSTANT"] == 43 assert clsdict["__doc__"] is None assert clsdict["method_c"](C()) == C().method_c() @@ -341,6 +346,24 @@ class CloudPickleTest(unittest.TestCase): g = pickle_depickle(f(), protocol=self.protocol) self.assertEqual(g(), 2) + def test_class_no_firstlineno_deletion_(self): + # `__firstlineno__` is a new attribute of classes introduced in Python 3.13. + # This attribute used to be automatically deleted when unpickling a class as a + # consequence of cloudpickle setting a class's `__module__` attribute at + # unpickling time (see https://github.com/python/cpython/blob/73c152b346a18ed8308e469bdd232698e6cd3a63/Objects/typeobject.c#L1353-L1356). + # This deletion would cause tests like + # `test_deterministic_dynamic_class_attr_ordering_for_chained_pickling` to fail. + # This test makes sure that the attribute `__firstlineno__` is preserved + # across a cloudpickle roundtrip. + + class A: + pass + + if hasattr(A, "__firstlineno__"): + A_roundtrip = pickle_depickle(A, protocol=self.protocol) + assert hasattr(A_roundtrip, "__firstlineno__") + assert A_roundtrip.__firstlineno__ == A.__firstlineno__ + def test_dynamically_generated_class_that_uses_super(self): class Base: