old_contents: 
  from scriptcore.testing.testcase import TestCase
  from scriptcore.console.asciimatics.widgets.checkbox import CheckBox
  from asciimatics.widgets import CheckBox as ACheckBox
  
  
  class TestCheckBox(TestCase):
  
      def test_checkbox(self):
          """
          Test the checkbox
          :return:    void
          """
  
          changed_checkbox = []
  
          def change_handler(checkbox):
              changed_checkbox.append(checkbox)
  
          checkbox = CheckBox(self.rand_str(), on_change=change_handler)
  
          self.assert_is_instance(checkbox, ACheckBox)
          for value in [True, False, True]:
              previous_count = len(changed_checkbox)
              checkbox.value = value
              self.assert_equal(previous_count + 1, len(changed_checkbox))
              self.assert_equal(checkbox, changed_checkbox[-1])
  
new_contents: 
  from scriptcore.testing.testcase import TestCase
  from scriptcore.console.asciimatics.widgets.checkbox import CheckBox
  from asciimatics.widgets import CheckBox as ACheckBox
  
  
  class TestCheckBox(TestCase):
  
      def test_checkbox(self):
          """
          Test the checkbox
          :return:    void
          """
  
          changed_checkbox = []
  
          def change_handler(checkbox):
              changed_checkbox.append(checkbox)
  
          checkbox = CheckBox(self.rand_str(), on_change=change_handler)
  
          self.assert_is_instance(checkbox, ACheckBox)
          for value in [True, False, True]:
              previous_count = len(changed_checkbox)
              checkbox.value = value
              self.assert_equal(value, checkbox.value)
              self.assert_equal(previous_count + 1, len(changed_checkbox))
              self.assert_equal(checkbox, changed_checkbox[-1])
  
subject: Check if checkbox value has updated.