def test_non_default_reading(self):
"""Ensure NullSensor returns the value given at initialization"""
ns = NullSensor('foo', 'bar', value='TESTVALUE')
self.assertEqual(ns.get_reading(), 'TESTVALUE')
def test_default_reading(self):
"""Ensure NullSensor returns None"""
ns = NullSensor('foo', 'bar')
self.assertTrue(ns.get_reading() is None)