text: import numpy as np
  import pytest
  
  import pandas as pd
  from pandas import SparseDtype
  import pandas.util.testing as tm
  
  
  class TestSeriesSubclassing:
  
      def test_indexing_sliced(self):
          s = tm.SubclassedSeries([1, 2, 3, 4], index=list('abcd'))
          res = s.loc[['a', 'b']]
          exp = tm.SubclassedSeries([1, 2], index=list('ab'))
          tm.assert_series_equal(res, exp)
  
          res = s.iloc[[2, 3]]
          exp = tm.SubclassedSeries([3, 4], index=list('cd'))
          tm.assert_series_equal(res, exp)
  
          res = s.loc[['a', 'b']]
          exp = tm.SubclassedSeries([1, 2], index=list('ab'))
          tm.assert_series_equal(res, exp)
  
      def test_to_frame(self):
          s = tm.SubclassedSeries([1, 2, 3, 4], index=list('abcd'), name='xxx')
          res = s.to_frame()
          exp = tm.SubclassedDataFrame({'xxx': [1, 2, 3, 4]}, index=list('abcd'))
          tm.assert_frame_equal(res, exp)
  
      def test_subclass_unstack(self):
          # GH 15564
          s = tm.SubclassedSeries(
              [1, 2, 3, 4], index=[list('aabb'), list('xyxy')])
  
          res = s.unstack()
          exp = tm.SubclassedDataFrame(
              {'x': [1, 3], 'y': [2, 4]}, index=['a', 'b'])
  
          tm.assert_frame_equal(res, exp)
  
  
  @pytest.mark.filterwarnings("ignore:Sparse:FutureWarning")
  class TestSparseSeriesSubclassing:
  
      def test_subclass_sparse_slice(self):
          # int64
          s = tm.SubclassedSparseSeries([1, 2, 3, 4, 5])
          exp = tm.SubclassedSparseSeries([2, 3, 4], index=[1, 2, 3])
          tm.assert_sp_series_equal(s.loc[1:3], exp)
          assert s.loc[1:3].dtype == SparseDtype(np.int64)
  
          exp = tm.SubclassedSparseSeries([2, 3], index=[1, 2])
          tm.assert_sp_series_equal(s.iloc[1:3], exp)
          assert s.iloc[1:3].dtype == SparseDtype(np.int64)
  
          exp = tm.SubclassedSparseSeries([2, 3], index=[1, 2])
          tm.assert_sp_series_equal(s[1:3], exp)
          assert s[1:3].dtype == SparseDtype(np.int64)
  
          # float64
          s = tm.SubclassedSparseSeries([1., 2., 3., 4., 5.])
          exp = tm.SubclassedSparseSeries([2., 3., 4.], index=[1, 2, 3])
          tm.assert_sp_series_equal(s.loc[1:3], exp)
          assert s.loc[1:3].dtype == SparseDtype(np.float64)
  
          exp = tm.SubclassedSparseSeries([2., 3.], index=[1, 2])
          tm.assert_sp_series_equal(s.iloc[1:3], exp)
          assert s.iloc[1:3].dtype == SparseDtype(np.float64)
  
          exp = tm.SubclassedSparseSeries([2., 3.], index=[1, 2])
          tm.assert_sp_series_equal(s[1:3], exp)
          assert s[1:3].dtype == SparseDtype(np.float64)
  
      def test_subclass_sparse_addition(self):
          s1 = tm.SubclassedSparseSeries([1, 3, 5])
          s2 = tm.SubclassedSparseSeries([-2, 5, 12])
          exp = tm.SubclassedSparseSeries([-1, 8, 17])
          tm.assert_sp_series_equal(s1 + s2, exp)
  
          s1 = tm.SubclassedSparseSeries([4.0, 5.0, 6.0])
          s2 = tm.SubclassedSparseSeries([1.0, 2.0, 3.0])
          exp = tm.SubclassedSparseSeries([5., 7., 9.])
          tm.assert_sp_series_equal(s1 + s2, exp)
  
      def test_subclass_sparse_to_frame(self):
          s = tm.SubclassedSparseSeries([1, 2], index=list('ab'), name='xxx')
          res = s.to_frame()
  
          exp_arr = pd.SparseArray([1, 2], dtype=np.int64, kind='block',
                                   fill_value=0)
          exp = tm.SubclassedSparseDataFrame({'xxx': exp_arr},
                                             index=list('ab'),
                                             default_fill_value=0)
          tm.assert_sp_frame_equal(res, exp)
  
          # create from int dict
          res = tm.SubclassedSparseDataFrame({'xxx': [1, 2]},
                                             index=list('ab'),
                                             default_fill_value=0)
          tm.assert_sp_frame_equal(res, exp)
  
          s = tm.SubclassedSparseSeries([1.1, 2.1], index=list('ab'),
                                        name='xxx')
          res = s.to_frame()
          exp = tm.SubclassedSparseDataFrame({'xxx': [1.1, 2.1]},
                                             index=list('ab'))
          tm.assert_sp_frame_equal(res, exp)
  