Testing friendship bond
In response to your comment on trusting new friends, I can say that we, humans, are highly social, and therefore, we must trust others, to some extent. That would be some degree of xenophobia if we failed to trust new acquaintances, which in the long term, would seriously tighten and constrict the circle of our friends.
I guess it’s a better idea to be more optimistic about the decent intentions of new people around us. However, as a cautious and introverted person, I believe we need to evaluate and analyze new people and acquaintances’ behavior and give more and more credit to them as they successfully pass some benchmarks or criteria.