in the  future, use log instead of Println

t.Log(...)

but even better, if you can keep it from logging unless something bad has happened, that's preferable. In the early stages we don't care so much though.

In this case, you know that you put in 5 valid wallets, so you are probably good with something as simple as a length verification. If there are other potential errors, you should test for them when the error would have been introduced (so, to verify that the wallets have the correct balance, you'd make sure after 'AddWallet' it had the correct balance added).