Issue #1515: Enable use of deepcopy() with instance methods. Patch by Robert Collins.

Lib/copy.py

@@ -260,6 +260,10 @@ def _deepcopy_dict(x, memo):
 if PyStringMap is not None:
     d[PyStringMap] = _deepcopy_dict
 
+def _deepcopy_method(x, memo): # Copy instance methods
+    return type(x)(x.im_func, deepcopy(x.im_self, memo), x.im_class)
+_deepcopy_dispatch[types.MethodType] = _deepcopy_method
+
 def _keep_alive(x, memo):
     """Keeps a reference to the object x in the memo.
 

Lib/test/test_copy.py

@@ -672,6 +672,17 @@ def __init__(self, i):
         del d
         self.assertEqual(len(v), 1)
 
+    def test_deepcopy_bound_method(self):
+        class Foo(object):
+            def m(self):
+                pass
+        f = Foo()
+        f.b = f.m
+        g = copy.deepcopy(f)
+        self.assertEqual(g.m, g.b)
+        self.assertTrue(g.b.im_self is g)
+        g.b()
+
 
 def global_foo(x, y): return x+y
 

Misc/ACKS

@@ -145,6 +145,7 @@ Josh Cogliati
 Dave Cole
 Benjamin Collar
 Jeffery Collins
+Robert Collins
 Paul Colomiets
 Matt Conway
 David M. Cooke

Misc/NEWS

@@ -483,6 +483,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #1515: Enable use of deepcopy() with instance methods.  Patch by
+  Robert Collins.
+
 - Issue #7403: logging: Fixed possible race condition in lock creation.
 
 - Issue #6845: Add restart support for binary upload in ftplib.  The