Puppy's first night at home, am I supposed to leave it alone...?

Basically all of the dog books I've read have told me to leave the puppy alone on it's first night at home to get used to a new place etc and even if it cries not to go and comfort it or it will become clingy and overly attached to you, but my friend said that he stayed with his puppy on it's first night to help toilet train it (in case it needed to go during the night) for the first couple of nights until it got used to toilet training, so what would be the appropriate thing to do here, stay up with the puppy to toilet train it properly or leave it until morning? Thank you