old_contents: #!/usr/bin/env python3
  #
  # Copyright 2011-2016 Google Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import itertools
  import unittest
  
  import sre_yield
  from sre_yield.testing_utils import UnitTest, data_provider
  
  
  class ExtractSliceType:
      """
      This exists so we can index obj[a:b:c] and get back a slice type without
      worrying about whether its arguments get mangled.
      """
  
      def __getitem__(self, n):
          return n
  
  
  E = ExtractSliceType()
  
  # Confirm that the new slice_indices function behaves like SliceType.indices
  
  ARR = list(map(str, list(range(100))))
  REG = sre_yield.AllStrings(r"\d{1}|1\d|2\d|3\d|4\d|5\d|6\d|7\d|8\d|9\d")
  
  NUMS = [None, 0, 2, 5, 80, 90, -20, -10, -1, 100, 110]
  
  TESTCASES = list(itertools.combinations(NUMS, 3))
  
  
  class SlicingTest(UnitTest):
      def test_prereqs(self):
          # TODO: Order of sre_yield may change at some point, to increment LSB
          # first.
          self.assertEqual(ARR, list(REG))
  
      @data_provider(TESTCASES)
      def test_indices(self, start, stop, step):
          st = E[start:stop:step]
          expected = st.indices(100)
          # print("expected", expected)
          actual = sre_yield.slice_indices(st, 100)
          # print("actual", actual)
          # print("array", ARR[st])
          self.assertEqual(expected, actual)
  
      @data_provider(TESTCASES)
      def test_content(self, start, stop, step):
          st = E[start:stop:step]
          indices = st.indices(100)  # noqa: F841
          # print("indices", indices)
          expected = ARR[st]
          # print("expected", expected)
          actual = list(REG[st])
          # print("actual", actual)
          self.assertEqual(expected, actual)
  
  
  if __name__ == "__main__":
      unittest.main()
  
new_contents: #!/usr/bin/env python3
  #
  # Copyright 2011-2016 Google Inc.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import itertools
  import unittest
  
  import sre_yield
  from sre_yield.testing_utils import UnitTest, data_provider
  
  
  class ExtractSliceType:
      """
      This exists so we can index obj[a:b:c] and get back a slice type without
      worrying about whether its arguments get mangled.
      """
  
      def __getitem__(self, n):
          return n
  
  
  E = ExtractSliceType()
  
  # Confirm that the new slice_indices function behaves like SliceType.indices
  
  ARR = list(map(str, list(range(100))))
  REG_RAW = r"\d{1}|1\d|2\d|3\d|4\d|5\d|6\d|7\d|8\d|9\d"
  
  NUMS = [None, 0, 2, 5, 80, 90, -20, -10, -1, 100, 110]
  
  TESTCASES = list(itertools.combinations(NUMS, 3))
  
  
  class SlicingTest(UnitTest):
      def test_prereqs(self):
          # TODO: Order of sre_yield may change at some point, to increment LSB
          # first.
          REG = sre_yield.AllStrings(REG_RAW)
          self.assertEqual(ARR, list(REG))
  
      @data_provider(TESTCASES)
      def test_indices(self, start, stop, step):
          st = E[start:stop:step]
          expected = st.indices(100)
          # print("expected", expected)
          actual = sre_yield.slice_indices(st, 100)
          # print("actual", actual)
          # print("array", ARR[st])
          self.assertEqual(expected, actual)
  
      @data_provider(TESTCASES)
      def test_content(self, start, stop, step):
          st = E[start:stop:step]
          indices = st.indices(100)  # noqa: F841
          # print("indices", indices)
          expected = ARR[st]
          # print("expected", expected)
          REG = sre_yield.AllStrings(REG_RAW)
          actual = list(REG[st])
          # print("actual", actual)
          self.assertEqual(expected, actual)
  
  
  if __name__ == "__main__":
      unittest.main()
  
subject: Move instantiation into test methods