Handle Python subclasses of Cdef classes.

Cython/Compiler/ParseTreeTransforms.py

@@ -1603,10 +1603,17 @@ if VALUE is not None:
             unpickle_func_name = '__pyx_unpickle_%s' % node.class_name
 
             unpickle_func = TreeFragment(u"""
-                def %(unpickle_func_name)s(%(args)s):
+                def %(unpickle_func_name)s(__pyx_type, __pyx_state, %(args)s):
                     cdef %(class_name)s result
-                    result = %(class_name)s.__new__(%(class_name)s)
+                    result = %(class_name)s.__new__(__pyx_type)
                     %(assignments)s
+                    if hasattr(result, '__setstate__'):
+                        result.__setstate__(__pyx_state)
+                    elif hasattr(result, '__dict__'):
+                        result.__dict__.update(__pyx_state)
+                    elif __pyx_state is not None:
+                        from pickle import PickleError
+                        raise PickleError("Unexpected state: %%s" %% __pyx_state)
                     return result
                 """ % {
                     'unpickle_func_name': unpickle_func_name,
@@ -1620,7 +1627,13 @@ if VALUE is not None:
 
             pickle_func = TreeFragment(u"""
                 def __reduce__(self):
-                    return %s, (%s)
+                    if hasattr(self, '__getstate__'):
+                        state = self.__getstate__()
+                    elif hasattr(self, '__dict__'):
+                        state = self.__dict__
+                    else:
+                        state = None
+                    return %s, (type(self), state, %s)
                 """ % (unpickle_func_name, ', '.join('self.%s' % v for v in all_members_names)),
                 level='c_class', pipeline=[NormalizeTree(None)]).substitute({})
             pickle_func.analyse_declarations(node.scope)

tests/run/reduce_pickle.pyx

@@ -68,8 +68,8 @@ cdef class DefaultReduce(object):
     DefaultReduce(i=11, s='abc')
     """
 
-    cdef int i
-    cdef str s
+    cdef readonly int i
+    cdef readonly str s
 
     def __init__(self, i=0, s=None):
         self.i = i
@@ -98,6 +98,22 @@ cdef class DefaultReduceSubclass(DefaultReduce):
         return "DefaultReduceSubclass(i=%s, s=%r, x=%s)" % (self.i, self.s, self.x)
 
 
+class DefaultReducePySubclass(DefaultReduce):
+    """
+    >>> a = DefaultReducePySubclass(i=11, s='abc', x=1.5); a
+    DefaultReducePySubclass(i=11, s='abc', x=1.5)
+    >>> import pickle
+    >>> pickle.loads(pickle.dumps(a))
+    DefaultReducePySubclass(i=11, s='abc', x=1.5)
+    """
+    def __init__(self, **kwargs):
+        self.x = kwargs.pop('x', 0)
+        super(DefaultReducePySubclass, self).__init__(**kwargs)
+
+    def __repr__(self):
+        return "DefaultReducePySubclass(i=%s, s=%r, x=%s)" % (self.i, self.s, self.x)
+
+
 cdef class NoReduceDueToIntPtr(object):
     """
     >>> import pickle