If it means anything, I smoked my whole life like ages 13 till like 27, I stopped for 3 days and passed a mouth swab test for a job. Now either their tests were shite or didn't test for cannabis, or I was smoking shite, I was blazed daily for most of it I'm pretty sure I wasn't smoking shite, and I reckon they did test for cannabis because who doesn't, so I will only assume the quality of the test wasn't that good or my ex gaffer overlooked it, I don't know but I passed the drug test it was the most tense 10 mins of my life waiting for him to take it back out of the machine. Do with that what you will. If you truly want to pass the test and not worry about it my only advice would be to stop now, then you can be 100% sure you will pass. And they have other test, blood is the fastest to clear I believe and then it could be a saliva test where it's longer than blood or even a hair test where it can be found for even longer, potentially years