How to test ground/neutral without outlets?
You can use the tester below.  If you touch one probe to the hot and the other to neutral or ground and the bulb should light.

If hot-to-ground lights but not hot-to-neutral the neutral is open. Vice versa for open ground. If you get nothing lighting either both neutral and ground are open or there's no power.

If hot-to-neutral and neutral-to-ground light, hot and neutral are reversed.

If neutral-to-ground and ground-to-hot light, but hot-to-neutral doesn't light, hot and ground are reversed.


http://byramlabs.com/store/images/hi-res/SPE-et-201a.gif

It's a little complicated. Since there's no outlet hooked up you should probably just test to make sure the black-to-white and black-to-green light the light, if not there's a problem further down the line.

I mostly use this kind of tester to see which wires are hot in old work with cloth covered wires that you can't tell which color is which anymore.

It's also a handy tool to have to test all the wires in a box to make sure there's no power in any of them before you start touching them with your hands.