Fixed Python-Markdown#85. Odict now handles link errors correctly.

Also added a test. Thanks for the report.

markdown/odict.py

@@ -150,13 +150,13 @@ def link(self, key, location):
         """ Change location of an existing item. """
         n = self.keyOrder.index(key)
         del self.keyOrder[n]
-        i = self.index_for_location(location)
         try:
+            i = self.index_for_location(location)
             if i is not None:
                 self.keyOrder.insert(i, key)
             else:
                 self.keyOrder.append(key)
-        except Error:
+        except Exception as e:
             # restore to prevent data loss and reraise
             self.keyOrder.insert(n, key)
-            raise Error
+            raise e

tests/test_apis.py

@@ -214,6 +214,14 @@ def testChangeOrder(self):
                     [('first', 'This'), ('fourth', 'self'),
                     ('third', 'a'), ('fifth', 'test')])
 
+    def textBadLink(self):
+        """ Test OrderedDict change order with bad location. """
+        self.assertRaises(ValueError, self.odict.link('fourth', '<bad'))
+        # Check for data integrity ("fourth" wasn't deleted).'
+        self.assertEqual(self.odict.items(),
+                    [('first', 'This'), ('third', 'a'), 
+                    ('fourth', 'self'), ('fifth', 'test')])
+
 class TestErrors(unittest.TestCase):
     """ Test Error Reporting. """