Golang : Go test needs internet connection for every run?

I would like to know if there is a possibility to run go test without actually needing an internet connection.

I guess that go test is looking for packages every time we run it but isn't there a way to tell him "no it's ok I already have all the packages just run the tests"?

Because when coding on the train or simply in a place where you don't have the internet, this is a problem.

Thanks for your answers.