Index: shutil.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/shutil.py,v
retrieving revision 1.28
diff -u -r1.28 shutil.py
--- shutil.py	23 Feb 2003 21:36:32 -0000	1.28
+++ shutil.py	5 Jun 2004 14:04:25 -0000
@@ -8,6 +8,7 @@
 import sys
 import stat
 import exceptions
+from os.path import abspath
 
 __all__ = ["copyfileobj","copyfile","copymode","copystat","copy","copy2",
            "copytree","move","rmtree","Error"]
@@ -164,8 +165,13 @@
         os.rename(src, dst)
     except OSError:
         if os.path.isdir(src):
+            if is_destination_in_source(src, dst):
+                raise Error, "Cannot move a directory '%s' into itself '%s'." % (src, dst)
             copytree(src, dst, symlinks=True)
             rmtree(src)
         else:
             copy2(src,dst)
             os.unlink(src)
+
+def is_destination_in_source(self, src, dst):
+    return abspath(dst).startswith(abspath(src))

Index: test/test_shutil.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/test/test_shutil.py,v
retrieving revision 1.2
diff -u -r1.2 test_shutil.py
--- test/test_shutil.py	1 May 2003 17:45:49 -0000	1.2
+++ test/test_shutil.py	5 Jun 2004 14:04:26 -0000
@@ -3,6 +3,7 @@
 import unittest
 import shutil
 import tempfile
+from os import path
 from test import test_support
 
 class TestShutil(unittest.TestCase):
@@ -12,11 +13,14 @@
         self.assertRaises(OSError, shutil.rmtree, filename)
         self.assertEqual(shutil.rmtree(filename, True), None)
 
+    def test_dont_move_dir_in_itself(self):
+        src_dir = tempfile.mkdtemp()
+        dst = path.join(src_dir, 'foo')
+        self.assertRaises(shutil.Error, shutil.move, src_dir, dst)
 
 
 def test_main():
     test_support.run_unittest(TestShutil)
 
-
 if __name__ == '__main__':
     test_main()