Fixes to improve compatibility of _Storage with dict

tests/test_storage.py

@@ -114,3 +114,23 @@ def test_clear(self):
         storage.clear()
         with open(filename) as inp:
             self.assertEqual(inp.read(), '{}')
+
+    def test_dict_compatibility(self):
+        """Test that the _Storage class fully implements dict()"""
+        filename = '/tmp/testdict1.json'
+        storage1 = _Storage(filename, file_format='json')
+        storage2 = _Storage(filename.replace('1','2'), file_format='json')
+        storage1['key'] = 'abc'
+        self.assertEqual(storage1, storage1, '%s is equal to itself' % dict(storage1))
+        self.assertNotEqual(storage1, storage2, '%s & %s are not equal' % (dict(storage1), dict(storage2)))
+        self.assertGreater(storage1, storage2, '%s > %s' % (dict(storage1), dict(storage2)))
+        self.assertLess(storage2, storage1, '%s < %s' % (dict(storage1), dict(storage2)))
+        self.assertEqual(len(storage1),1)
+        self.assertEqual(len(storage2),0)
+        self.assertTrue(bool(storage1), 'non-empty objects test True')
+        self.assertFalse(bool(storage2), 'empty objects test False')
+        self.assertTrue(storage1.has_key('key'))
+        self.assertFalse(storage1.has_key('non-key'))
+
+
+

xbmcswift2/storage.py

@@ -105,12 +105,12 @@ def raw_dict(self):
 class _Storage(collections.MutableMapping, _PersistentDictMixin):
     '''Storage that acts like a dict but also can persist to disk.
 
-    :param filename: An absolute filepath to reprsent the storage on disk. The
+    :param filename: An absolute filepath to represent the storage on disk. The
                      storage will loaded from this file if it already exists,
                      otherwise the file will be created.
     :param file_format: 'pickle', 'json' or 'csv'. pickle is the default. Be
                         aware that json and csv have limited support for python
-                        objets.
+                        objects.
 
     .. warning:: Currently there are no limitations on the size of the storage.
                  Please be sure to call :meth:`~xbmcswift2._Storage.clear`
@@ -135,13 +135,29 @@ def __iter__(self):
         return iter(self._items)
 
     def __len__(self):
-        return self._items.__len__
+        return self._items.__len__()
+
+    def viewkeys(self):
+        return self._items.viewkeys()
+
+    def viewitems(self):
+        return dict(self).viewitems()
+
+    def viewvalues(self):
+        return dict(self).viewvalues()
+
+    # without defining this, cmp() still works, but it looks like all _Storage() 
+    # objects are equal 
+    # I don't compare the underlying dicts because of the timestamps
+    def __cmp__(self, other):
+        return cmp(dict(self), dict(other))
 
     def raw_dict(self):
         '''Returns the wrapped dict'''
         return self._items
 
     initial_update = collections.MutableMapping.update
+    has_key        = collections.MutableMapping.__contains__
 
     def clear(self):
         super(_Storage, self).clear()