def testSelection(self): b1 = Mock(spec=Buffer) b2 = Mock(spec=Buffer) blist = BufferList() self.assertEqual(blist.add(b1), b1) self.assertIsNotNone(blist.current) self.assertIsNot(blist.current, b1) self.assertEqual(blist.addAndSelect(b2), b2) self.assertEqual(blist.current, b2) self.assertEqual(blist.select(b1), b1) self.assertEqual(blist.current, b1)