testing light bulbs

Just give the assembly to a supply.

Yes.. connect them to a supply using the correct ballast, if they ignite and produce light, they work, if not throw them out and buy new!

Yeah, could understand why most of the gurus have such an answer. The Op should be more specified.

There are electrical and mechanical standards the lights are built to, you could test them against those if you are

a) Building you own lights, or

b) Suspect that the lights are of dubious quality and need to be quality checked

This however seems unlikely.

Do you perhaps mean testing the light output and pattern against the manufacturers photometric data for the light?

If the light is working, and you have a rooster, he'll start crowing when the on/off discriminator is positioned in the "on" position and exposed to the visible light spectrum of the bulb under test. The rooster will need a rest between cycles to reset his internal mechanisms. Repeat as necessary. Btw, if the rooster does not crow, you can assume the bulb is defective, or the rooster is. Either way, it's a good test for bulbs and roosters. Maybe you just need a new rooster.