They make a hardware device for this, it has several usb plugs on it, and two rows of LEDs that light up if the wires are all connected.
See above thread for more details and links:
https://news.ycombinator.com/item?id=45513256
yes. not that expensive.
See above thread for more details and links:
https://news.ycombinator.com/item?id=45513256