Use @deprecated for Registry.add()

markdown/util.py

@@ -423,6 +423,7 @@ def __delitem__(self, key):
         else:
             raise KeyError('Cannot delete key {}, not registered.'.format(key))
 
+    @deprecated('Use the `register` method instead.')
     def add(self, key, value, location):
         """ Register a key by location. """
         if len(self) == 0:
@@ -459,12 +460,6 @@ def add(self, key, value, location):
             raise ValueError('Not a valid location: "%s". Location key '
                              'must start with a ">" or "<".' % location)
         self.register(value, key, priority)
-        warnings.warn(
-            'Using the add method to register a processor or pattern is deprecated. '
-            'Use the `register` method instead.',
-            DeprecationWarning,
-            stacklevel=2,
-        )
 
 
 def __getattr__(name):

tests/test_apis.py

@@ -420,7 +420,7 @@ def testRegistryDeprecatedAdd(self):
                 r.add('f', Item('f'), 'badlocation')
 
             # Check the warnings
-            self.assertEqual(len(w), 7)
+            self.assertEqual(len(w), 8)
             self.assertTrue(all(issubclass(x.category, DeprecationWarning) for x in w))