forwardport of 2.3.5 fixes to copy.py

1 files changed, 101 insertions, 0 deletions

diff --git a/Lib/test/test_copy.py b/Lib/test/test_copy.py
index bd5a3e1..02dede4 100644
--- a/Lib/test/test_copy.py
+++ b/Lib/test/test_copy.py
@@ -166,6 +166,107 @@ class TestCopy(unittest.TestCase):
         x = C(42)
         self.assertEqual(copy.copy(x), x)
 
+    # tests for copying extension types, iff module trycopy is installed
+    def test_copy_classictype(self):
+        from _testcapi import make_copyable
+        x = make_copyable([23])
+        y = copy.copy(x)
+        self.assertEqual(x, y)
+        self.assertEqual(x.tag, y.tag)
+        self.assert_(x is not y)
+        self.assert_(x.tag is y.tag)
+
+    def test_deepcopy_classictype(self):
+        from _testcapi import make_copyable
+        x = make_copyable([23])
+        y = copy.deepcopy(x)
+        self.assertEqual(x, y)
+        self.assertEqual(x.tag, y.tag)
+        self.assert_(x is not y)
+        self.assert_(x.tag is not y.tag)
+
+    # regression tests for class-vs-instance and metaclass-confusion
+    def test_copy_classoverinstance(self):
+        class C(object):
+            def __init__(self, v):
+                self.v = v
+            def __cmp__(self, other):
+                return -cmp(other, self.v)
+            def __copy__(self):
+                return self.__class__(self.v)
+        x = C(23)
+        self.assertEqual(copy.copy(x), x)
+        x.__copy__ = lambda: 42
+        self.assertEqual(copy.copy(x), x)
+
+    def test_deepcopy_classoverinstance(self):
+        class C(object):
+            def __init__(self, v):
+                self.v = v
+            def __cmp__(self, other):
+                return -cmp(other, self.v)
+            def __deepcopy__(self, memo):
+                return self.__class__(copy.deepcopy(self.v, memo))
+        x = C(23)
+        self.assertEqual(copy.deepcopy(x), x)
+        x.__deepcopy__ = lambda memo: 42
+        self.assertEqual(copy.deepcopy(x), x)
+
+
+    def test_copy_metaclassconfusion(self):
+        class MyOwnError(copy.Error):
+            pass
+        class Meta(type):
+            def __copy__(cls):
+                raise MyOwnError("can't copy classes w/this metaclass")
+        class C:
+            __metaclass__ = Meta
+            def __init__(self, tag):
+                self.tag = tag
+            def __cmp__(self, other):
+                return -cmp(other, self.tag)
+        # the metaclass can forbid shallow copying of its classes
+        self.assertRaises(MyOwnError, copy.copy, C)
+        # check that there is no interference with instances
+        x = C(23)
+        self.assertEqual(copy.copy(x), x)
+
+    def test_deepcopy_metaclassconfusion(self):
+        class MyOwnError(copy.Error):
+            pass
+        class Meta(type):
+            def __deepcopy__(cls, memo):
+                raise MyOwnError("can't deepcopy classes w/this metaclass")
+        class C:
+            __metaclass__ = Meta
+            def __init__(self, tag):
+                self.tag = tag
+            def __cmp__(self, other):
+                return -cmp(other, self.tag)
+        # types are ALWAYS deepcopied atomically, no matter what
+        self.assertEqual(copy.deepcopy(C), C)
+        # check that there is no interference with instances
+        x = C(23)
+        self.assertEqual(copy.deepcopy(x), x)
+
+    def _nomro(self):
+        class C(type):
+            def __getattribute__(self, attr):
+                if attr == '__mro__':
+                    raise AttributeError, "What, *me*, a __mro__? Nevah!"
+                return super(C, self).__getattribute__(attr)
+        class D(object):
+            __metaclass__ = C
+        return D()
+
+    def test_copy_mro(self):
+        x = self._nomro()
+        y = copy.copy(x)
+
+    def test_deepcopy_mro(self):
+        x = self._nomro()
+        y = copy.deepcopy(x)
+
     # The deepcopy() method
 
     def test_deepcopy_basic(self):