old_contents: import sys
  import unittest
  
  from PyQt5 import QtGui, QtWidgets
  
  # set up import paths
  import sas.qtgui.path_prepare
  
  # Local
  from sas.qtgui.Plotting.SetGraphRange import SetGraphRange
  
  if not QtWidgets.QApplication.instance():
      app = QtWidgets.QApplication(sys.argv)
  
  class SetGraphRangeTest(unittest.TestCase):
      '''Test the SetGraphRange'''
      def setUp(self):
          '''Create the SetGraphRange'''
  
          self.widget = SetGraphRange(None)
  
      def tearDown(self):
          '''Destroy the GUI'''
          self.widget.close()
          self.widget = None
  
      def testDefaults(self):
          '''Test the GUI in its default state'''
          self.assertIsInstance(self.widget, QtWidgets.QDialog)
          self.assertEqual(self.widget.windowTitle(), "Set Graph Range")
          self.assertIsInstance(self.widget.txtXmin, QtWidgets.QLineEdit)
          self.assertIsInstance(self.widget.txtXmin.validator(), QtGui.QDoubleValidator)
          
      def testGoodRanges(self):
          '''Test the X range values set by caller''' 
          self.assertEqual(self.widget.xrange(), (0.0, 0.0))
          self.assertEqual(self.widget.yrange(), (0.0, 0.0))
  
          new_widget = SetGraphRange(None, ("1.0", 2.0), (8.0, "-2"))
          self.assertEqual(new_widget.xrange(), (1.0, 2.0))
          self.assertEqual(new_widget.yrange(), (8.0, -2.0))
  
  
      def testBadRanges(self):
          '''Test the incorrect X range values set by caller'''
          with self.assertRaises(ValueError):
              new_widget = SetGraphRange(None, ("1.0", "aa"), (None, "@"))
              self.assertEqual(new_widget.xrange(), (1.0, 0.0))
              self.assertEqual(new_widget.yrange(), (0.0, 0.0))
  
          with self.assertRaises(AssertionError):
              new_widget = SetGraphRange(None, "I'm a tuple", None)
              self.assertEqual(new_widget.xrange(), (1.0, 0.0))
              self.assertEqual(new_widget.yrange(), (0.0, 0.0))
  
  if __name__ == "__main__":
      unittest.main()
  
new_contents: import sys
  import unittest
  
  import pytest
  
  from PyQt5 import QtGui, QtWidgets
  
  # set up import paths
  import sas.qtgui.path_prepare
  
  # Local
  from sas.qtgui.Plotting.SetGraphRange import SetGraphRange
  
  if not QtWidgets.QApplication.instance():
      app = QtWidgets.QApplication(sys.argv)
  
  class SetGraphRangeTest(unittest.TestCase):
      '''Test the SetGraphRange'''
      def setUp(self):
          '''Create the SetGraphRange'''
  
          self.widget = SetGraphRange(None)
  
      def tearDown(self):
          '''Destroy the GUI'''
          self.widget.close()
          self.widget = None
  
      def testDefaults(self):
          '''Test the GUI in its default state'''
          assert isinstance(self.widget, QtWidgets.QDialog)
          assert self.widget.windowTitle() == "Set Graph Range"
          assert isinstance(self.widget.txtXmin, QtWidgets.QLineEdit)
          assert isinstance(self.widget.txtXmin.validator(), QtGui.QDoubleValidator)
          
      def testGoodRanges(self):
          '''Test the X range values set by caller''' 
          assert self.widget.xrange() == (0.0, 0.0)
          assert self.widget.yrange() == (0.0, 0.0)
  
          new_widget = SetGraphRange(None, ("1.0", 2.0), (8.0, "-2"))
          assert new_widget.xrange() == (1.0, 2.0)
          assert new_widget.yrange() == (8.0, -2.0)
  
  
      def testBadRanges(self):
          '''Test the incorrect X range values set by caller'''
          with pytest.raises(ValueError):
              new_widget = SetGraphRange(None, ("1.0", "aa"), (None, "@"))
              assert new_widget.xrange() == (1.0, 0.0)
              assert new_widget.yrange() == (0.0, 0.0)
  
          with pytest.raises(AssertionError):
              new_widget = SetGraphRange(None, "I'm a tuple", None)
              assert new_widget.xrange() == (1.0, 0.0)
              assert new_widget.yrange() == (0.0, 0.0)
  
  if __name__ == "__main__":
      unittest.main()
  
subject: Change tests to asserts in SetGraphRangeTest.py