minor fixes and changelog entry

Author: cgevans

beetsplug/duplicates.py

@@ -258,14 +258,14 @@ def _order(self, objs, tiebreak=None):
         if tiebreak and kind in tiebreak.keys():
             key = lambda x: tuple(getattr(x, k) for k in tiebreak[kind])
         else:
-            if kind is 'items':
+            if kind == 'items':
                 def truthy(v):
                     # Avoid a Unicode warning by avoiding comparison
                     # between a bytes object and the empty Unicode
                     # string ''.
                     return v is not None and \
                         (v != '' if isinstance(v, six.text_type) else True)
-                fields = kind.all_keys()
+                fields = Item.all_keys()
                 key = lambda x: sum(1 for f in fields if truthy(getattr(x, f)))
             else:
                 key = lambda x: len(x.items())

docs/changelog.rst

@@ -70,6 +70,8 @@ Fixes:
   Python 3 on Windows with non-ASCII filenames. :bug:`2671`
 * :doc:`/plugins/absubmit`: Fix an occasional crash on Python 3 when the AB
   analysis tool produced non-ASCII metadata. :bug:`2673`
+* :doc:`/plugins/duplicates`: Use default tiebreak for any kind (item/album) that
+  does not have a tiebreak specified in the configuration.
 * :doc:`/plugins/duplicates`: Fix the `--key` command line option, which was
   ignored.
 * :doc:`/plugins/replaygain`: Fix album replaygain calculation with the