Merged revisions 77573 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r77573 | antoine.pitrou | 2010-01-17 13:26:20 +0100 (dim., 17 janv. 2010) | 6 lines

  Issue #7561: Operations on empty bytearrays (such as `int(bytearray())`)
  could crash in many places because of the PyByteArray_AS_STRING() macro
  returning NULL.  The macro now returns a statically allocated empty
  string instead.
........
diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index a4e5bd9..2813d96 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -817,6 +817,14 @@
         self.assertRaises(BufferError, delslice)
         self.assertEquals(b, orig)
 
+    def test_empty_bytearray(self):
+        # Issue #7561: operations on empty bytearrays could crash in many
+        # situations, due to a fragile implementation of the
+        # PyByteArray_AS_STRING() C macro.
+        self.assertRaises(ValueError, int, bytearray(b''))
+        self.assertRaises((ValueError, OSError), os.mkdir, bytearray(b''))
+
+
 class AssortedBytesTest(unittest.TestCase):
     #
     # Test various combinations of bytes and bytearray