Test how animation methods react to too few arguments. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS requestAnimationFrame() threw exception TypeError: Failed to execute 'requestAnimationFrame' on 'Window': 1 argument required, but only 0 present.. PASS cancelAnimationFrame() threw exception TypeError: Failed to execute 'cancelAnimationFrame' on 'Window': 1 argument required, but only 0 present.. PASS successfullyParsed is true TEST COMPLETE