From: Fred Drake <fdrake@acm.org>
Date: Wed, 11 Oct 2000 22:16:45 +0000 (+0000)
Subject: In the module docstring, clarify that this is used to register pickle
X-Git-Tag: v2.0~96
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=78a6a369641d53c4085eb167af0d1cef65c129fe;p=python

In the module docstring, clarify that this is used to register pickle
support for extension types, not classes.

pickle():  If the type is a class or if the reduction function is not
           callable, raise a TypeError.

constructor():  If the constructor is not callable, raise TypeError.

This (partially) closes SourceForge patch #101859.
---

diff --git a/Lib/copy_reg.py b/Lib/copy_reg.py
index d0953bf08b..6a8881d0a1 100644
--- a/Lib/copy_reg.py
+++ b/Lib/copy_reg.py
@@ -1,15 +1,28 @@
-"""Helper to provide extensibility for pickle/cPickle."""
+"""Helper to provide extensibility for pickle/cPickle.
+
+This is only useful to add pickle support for extension types defined in
+C, not for instances of user-defined classes.
+"""
+
+from types import ClassType as _ClassType
 
 dispatch_table = {}
 safe_constructors = {}
 
-def pickle(ob_type, pickle_function, constructor_ob = None):
+def pickle(ob_type, pickle_function, constructor_ob=None):
+    if type(ob_type) is _ClassType:
+        raise TypeError("copy_reg is not intended for use with classes")
+
+    if not callable(pickle_function):
+        raise TypeError("reduction functions must be callable")
     dispatch_table[ob_type] = pickle_function
 
     if constructor_ob is not None:
         constructor(constructor_ob)
 
 def constructor(object):
+    if not callable(object):
+        raise TypeError("constructors must be callable")
     safe_constructors[object] = 1
 
 # Example: provide pickling support for complex numbers.
@@ -18,4 +31,3 @@ def pickle_complex(c):
     return complex, (c.real, c.imag)
 
 pickle(type(1j), pickle_complex, complex)
-