default_index inherits index.name

Author: minggli

pandas/core/series.py

@@ -1200,7 +1200,7 @@ def reset_index(self, level=None, drop=False, name=None, inplace=False):
         """
         inplace = validate_bool_kwarg(inplace, 'inplace')
         if drop:
-            new_index = ibase.default_index(len(self))
+            new_index = ibase.default_index(len(self), name=self.index.name)
             if level is not None:
                 if not isinstance(level, (tuple, list)):
                     level = [level]