text: """
  This file contains a minimal set of tests for compliance with the extension
  array interface test suite, and should contain no other tests.
  The test suite for the full functionality of the array is located in
  `pandas/tests/arrays/`.
  
  The tests in this file are inherited from the BaseExtensionTests, and only
  minimal tweaks should be applied to get the tests passing (by overwriting a
  parent method).
  
  Additional tests should either be added to one of the BaseExtensionTests
  classes (if they are relevant for the extension interface for all dtypes), or
  be added to the array-specific tests in `pandas/tests/arrays/`.
  
  """
  import numpy as np
  import pytest
  
  from pandas._libs import iNaT
  
  from pandas.core.dtypes.dtypes import PeriodDtype
  
  import pandas as pd
  from pandas.core.arrays import PeriodArray
  from pandas.tests.extension import base
  
  
  @pytest.fixture
  def dtype():
      return PeriodDtype(freq="D")
  
  
  @pytest.fixture
  def data(dtype):
      return PeriodArray(np.arange(1970, 2070), freq=dtype.freq)
  
  
  @pytest.fixture
  def data_for_twos(dtype):
      return PeriodArray(np.ones(100) * 2, freq=dtype.freq)
  
  
  @pytest.fixture
  def data_for_sorting(dtype):
      return PeriodArray([2018, 2019, 2017], freq=dtype.freq)
  
  
  @pytest.fixture
  def data_missing(dtype):
      return PeriodArray([iNaT, 2017], freq=dtype.freq)
  
  
  @pytest.fixture
  def data_missing_for_sorting(dtype):
      return PeriodArray([2018, iNaT, 2017], freq=dtype.freq)
  
  
  @pytest.fixture
  def data_for_grouping(dtype):
      B = 2018
      NA = iNaT
      A = 2017
      C = 2019
      return PeriodArray([B, B, NA, NA, A, A, B, C], freq=dtype.freq)
  
  
  @pytest.fixture
  def na_value():
      return pd.NaT
  
  
  class BasePeriodTests:
      pass
  
  
  class TestPeriodDtype(BasePeriodTests, base.BaseDtypeTests):
      pass
  
  
  class TestConstructors(BasePeriodTests, base.BaseConstructorsTests):
      pass
  
  
  class TestGetitem(BasePeriodTests, base.BaseGetitemTests):
      pass
  
  
  class TestMethods(BasePeriodTests, base.BaseMethodsTests):
      def test_combine_add(self, data_repeated):
          # Period + Period is not defined.
          pass
  
  
  class TestInterface(BasePeriodTests, base.BaseInterfaceTests):
  
      pass
  
  
  class TestArithmeticOps(BasePeriodTests, base.BaseArithmeticOpsTests):
      implements = {"__sub__", "__rsub__"}
  
      def test_arith_frame_with_scalar(self, data, all_arithmetic_operators):
          # frame & scalar
          if all_arithmetic_operators in self.implements:
              df = pd.DataFrame({"A": data})
              self.check_opname(df, all_arithmetic_operators, data[0], exc=None)
          else:
              # ... but not the rest.
              super().test_arith_frame_with_scalar(data, all_arithmetic_operators)
  
      def test_arith_series_with_scalar(self, data, all_arithmetic_operators):
          # we implement substitution...
          if all_arithmetic_operators in self.implements:
              s = pd.Series(data)
              self.check_opname(s, all_arithmetic_operators, s.iloc[0], exc=None)
          else:
              # ... but not the rest.
              super().test_arith_series_with_scalar(data, all_arithmetic_operators)
  
      def test_arith_series_with_array(self, data, all_arithmetic_operators):
          if all_arithmetic_operators in self.implements:
              s = pd.Series(data)
              self.check_opname(s, all_arithmetic_operators, s.iloc[0], exc=None)
          else:
              # ... but not the rest.
              super().test_arith_series_with_scalar(data, all_arithmetic_operators)
  
      def _check_divmod_op(self, s, op, other, exc=NotImplementedError):
          super()._check_divmod_op(s, op, other, exc=TypeError)
  
      def test_add_series_with_extension_array(self, data):
          # we don't implement + for Period
          s = pd.Series(data)
          msg = (
              r"unsupported operand type\(s\) for \+: "
              r"\'PeriodArray\' and \'PeriodArray\'"
          )
          with pytest.raises(TypeError, match=msg):
              s + data
  
      @pytest.mark.parametrize("box", [pd.Series, pd.DataFrame])
      def test_direct_arith_with_ndframe_returns_not_implemented(self, data, box):
          # Override to use __sub__ instead of __add__
          other = pd.Series(data)
          if box is pd.DataFrame:
              other = other.to_frame()
  
          result = data.__sub__(other)
          assert result is NotImplemented
  
  
  class TestCasting(BasePeriodTests, base.BaseCastingTests):
      pass
  
  
  class TestComparisonOps(BasePeriodTests, base.BaseComparisonOpsTests):
      def _compare_other(self, s, data, op_name, other):
          # the base test is not appropriate for us. We raise on comparison
          # with (some) integers, depending on the value.
          pass
  
  
  class TestMissing(BasePeriodTests, base.BaseMissingTests):
      pass
  
  
  class TestReshaping(BasePeriodTests, base.BaseReshapingTests):
      pass
  
  
  class TestSetitem(BasePeriodTests, base.BaseSetitemTests):
      pass
  
  
  class TestGroupby(BasePeriodTests, base.BaseGroupbyTests):
      pass
  
  
  class TestPrinting(BasePeriodTests, base.BasePrintingTests):
      pass
  
  
  class TestParsing(BasePeriodTests, base.BaseParsingTests):
      @pytest.mark.parametrize("engine", ["c", "python"])
      def test_EA_types(self, engine, data):
          super().test_EA_types(engine, data)
  
  
  class Test2DCompat(BasePeriodTests, base.Dim2CompatTests):
      pass
  