Don't collect names in ._shallow_copy, is done in .copy

Author: topper-123

pandas/core/indexes/multi.py

@@ -924,12 +924,12 @@ def __contains__(self, key):
 
     @Appender(_index_shared_docs['_shallow_copy'])
     def _shallow_copy(self, values=None, **kwargs):
-        names = kwargs.pop('names', kwargs.pop('name', self.names))
         if values is not None:
+            names = kwargs.pop('names', kwargs.pop('name', self.names))
             # discards freq
             kwargs.pop('freq', None)
             return MultiIndex.from_tuples(values, names=names, **kwargs)
-        return self.copy(names=names, **kwargs)
+        return self.copy(**kwargs)
 
     @cache_readonly
     def dtype(self):