FIX remove __annotate_func__ that return __dict__ within a closure Python 3.14 (#578)

Author: glemaitre

CHANGES.md

@@ -1,6 +1,12 @@
 In development
 ==============
 
+3.1.2
+=====
+
+- Fix pickling of classes containing type annotations for Python 3.14
+  ([PR#578](https://github.com/cloudpipe/cloudpickle/pull/578))
+
 3.1.1
 =====
 

cloudpickle/cloudpickle.py

@@ -783,6 +783,12 @@ def _class_getstate(obj):
 
     clsdict.pop("__dict__", None)  # unpicklable property object
 
+    if sys.version_info >= (3, 14):
+        # PEP-649/749: __annotate_func__ contains a closure that references the class
+        # dict. We need to exclude it from pickling. Python will recreate it when
+        # __annotations__ is accessed at unpickling time.
+        clsdict.pop("__annotate_func__", None)
+
     return (clsdict, {})
 
 
@@ -1190,6 +1196,10 @@ def _class_setstate(obj, state):
         for subclass in registry:
             obj.register(subclass)
 
+    # PEP-649/749: During pickling, we excluded the __annotate_func__ attribute but it
+    # will be created by Python. Subsequently, annotations will be recreated when
+    # __annotations__ is accessed.
+
     return obj
 
 

tests/cloudpickle_test.py

@@ -2672,6 +2672,22 @@ class C:
         C1 = pickle_depickle(C, protocol=self.protocol)
         assert C1.__annotations__ == C.__annotations__
 
+    def test_class_annotations_abstractclass(self):
+        # see https://github.com/cloudpipe/cloudpickle/issues/572
+
+        class C(abc.ABC):
+            a: int
+
+        C1 = pickle_depickle(C, protocol=self.protocol)
+        assert C1.__annotations__ == C.__annotations__
+        C2 = pickle_depickle(C1, protocol=self.protocol)
+        if sys.version_info >= (3, 14):
+            # check that __annotate_func__ is created by Python
+            assert hasattr(C2, "__annotate_func__")
+        assert C2.__annotations__ == C1.__annotations__
+        c2 = C2()
+        assert isinstance(c2, C2)
+
     def test_function_annotations(self):
         def f(a: int) -> str:
             pass