My bf just got a saliva drug test and he smokes pot and uses opiates, will they show?

He smokes pot every day so I assume that will definitely show, right? He says he hasn't used opiates (heroin) for 5 days but I have a feeling he's lying. He may have used 3 days ago (he seemed like he was on it when I saw him that day). How long do these drugs stay in your saliva for a swab test?

: http://alcoholdrugstreatment.info/my-bf-just-got-a-saliva-drug-test-and-he-smokes-pot-and-uses-opiates-will-they-show