diff --git a/Lib/copy.py b/Lib/copy.py index 3f2033f5ffd..d3db93d08d1 100644 --- a/Lib/copy.py +++ b/Lib/copy.py @@ -49,6 +49,7 @@ __getstate__() and __setstate__(). See the documentation for module """ import types +import weakref from copy_reg import dispatch_table class Error(Exception): @@ -102,7 +103,7 @@ def _copy_immutable(x): for t in (type(None), int, long, float, bool, str, tuple, frozenset, type, xrange, types.ClassType, types.BuiltinFunctionType, type(Ellipsis), - types.FunctionType): + types.FunctionType, weakref.ref): d[t] = _copy_immutable for name in ("ComplexType", "UnicodeType", "CodeType"): t = getattr(types, name, None) @@ -220,6 +221,7 @@ d[xrange] = _deepcopy_atomic d[types.ClassType] = _deepcopy_atomic d[types.BuiltinFunctionType] = _deepcopy_atomic d[types.FunctionType] = _deepcopy_atomic +d[weakref.ref] = _deepcopy_atomic def _deepcopy_list(x, memo): y = [] diff --git a/Lib/test/test_copy.py b/Lib/test/test_copy.py index be334ccf059..a8be8872099 100644 --- a/Lib/test/test_copy.py +++ b/Lib/test/test_copy.py @@ -2,6 +2,8 @@ import copy import copy_reg +import weakref +import operator import unittest from test import test_support @@ -585,6 +587,92 @@ class TestCopy(unittest.TestCase): bar = lambda: None self.assertEqual(copy.deepcopy(bar), bar) + def _check_weakref(self, _copy): + class C(object): + pass + obj = C() + x = weakref.ref(obj) + y = _copy(x) + self.assertTrue(y is x) + del obj + y = _copy(x) + self.assertTrue(y is x) + + def test_copy_weakref(self): + self._check_weakref(copy.copy) + + def test_deepcopy_weakref(self): + self._check_weakref(copy.deepcopy) + + def _check_copy_weakdict(self, _dicttype): + class C(object): + pass + a, b, c, d = [C() for i in xrange(4)] + u = _dicttype() + u[a] = b + u[c] = d + v = copy.copy(u) + self.assertFalse(v is u) + self.assertEqual(v, u) + self.assertEqual(v[a], b) + self.assertEqual(v[c], d) + self.assertEqual(len(v), 2) + del c, d + self.assertEqual(len(v), 1) + x, y = C(), C() + # The underlying containers are decoupled + v[x] = y + self.assertFalse(x in u) + + def test_copy_weakkeydict(self): + self._check_copy_weakdict(weakref.WeakKeyDictionary) + + def test_copy_weakvaluedict(self): + self._check_copy_weakdict(weakref.WeakValueDictionary) + + def test_deepcopy_weakkeydict(self): + class C(object): + def __init__(self, i): + self.i = i + a, b, c, d = [C(i) for i in xrange(4)] + u = weakref.WeakKeyDictionary() + u[a] = b + u[c] = d + # Keys aren't copied, values are + v = copy.deepcopy(u) + self.assertNotEqual(v, u) + self.assertEqual(len(v), 2) + self.assertFalse(v[a] is b) + self.assertFalse(v[c] is d) + self.assertEqual(v[a].i, b.i) + self.assertEqual(v[c].i, d.i) + del c + self.assertEqual(len(v), 1) + + def test_deepcopy_weakvaluedict(self): + class C(object): + def __init__(self, i): + self.i = i + a, b, c, d = [C(i) for i in xrange(4)] + u = weakref.WeakValueDictionary() + u[a] = b + u[c] = d + # Keys are copied, values aren't + v = copy.deepcopy(u) + self.assertNotEqual(v, u) + self.assertEqual(len(v), 2) + (x, y), (z, t) = sorted(v.items(), key=lambda (k, v): k.i) + self.assertFalse(x is a) + self.assertEqual(x.i, a.i) + self.assertTrue(y is b) + self.assertFalse(z is c) + self.assertEqual(z.i, c.i) + self.assertTrue(t is d) + del x, y, z, t + del d + self.assertEqual(len(v), 1) + + def global_foo(x, y): return x+y def test_main(): diff --git a/Lib/weakref.py b/Lib/weakref.py index 78b74ad3207..84d81a27347 100644 --- a/Lib/weakref.py +++ b/Lib/weakref.py @@ -85,6 +85,17 @@ class WeakValueDictionary(UserDict.UserDict): new[key] = o return new + __copy__ = copy + + def __deepcopy__(self, memo): + from copy import deepcopy + new = self.__class__() + for key, wr in self.data.items(): + o = wr() + if o is not None: + new[deepcopy(key, memo)] = o + return new + def get(self, key, default=None): try: wr = self.data[key] @@ -256,6 +267,17 @@ class WeakKeyDictionary(UserDict.UserDict): new[o] = value return new + __copy__ = copy + + def __deepcopy__(self, memo): + from copy import deepcopy + new = self.__class__() + for key, value in self.data.items(): + o = key() + if o is not None: + new[o] = deepcopy(value, memo) + return new + def get(self, key, default=None): return self.data.get(ref(key),default) diff --git a/Misc/NEWS b/Misc/NEWS index 46e02fcfab8..aec2f2cb526 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -293,6 +293,9 @@ Core and Builtins Library ------- +- Issue #2116: Weak references and weak dictionaries now support copy()ing and + deepcopy()ing. + - Issue #1655: Make imaplib IPv6-capable. Patch by Derek Morr. - Issue #5918: Fix a crash in the parser module.