Funky test result

I was using one of those $15 three light circuit testers on a receptacle. the tester lit up indicating correct wiring. As I went to pull it out, my thumb pushed on the GFCI test button. With the test button pushed in the lights lit up as if the Hot and Neutral were reversed. I had the same thing at another inspection once. Anyone have any idea what would make this happen?

It means you pushed the test button. It is not indicative of any problem.

I guess that is good but why does it only happen on that outlet? I couldn’t get it to happen at any other outlets.

Try it again, it will.