I just had to take a P test for work. I've been unemployed for 6 months or more, but finally I got an interview the same day I called, and a guaranteed job if I pass the drug test. I take the test knowing I was smoking the night before and sure enough I fail and bye bye job.

I'd listen to the test, but definitely drink so much water (atleast 2 liters) a couple of hours before taking the test so that you are P-ing clear.