How to use loginVisitor()?

[darkcode85]

I have AccountsGuest.enabled set as false, now I want to login a visitor when they enter an email in one input, I have this code:

Template.test.events({
  'submit .new-user': function (event) {
    event.preventDefault();
    email = $('.input').val();
    Session.set('email', email);
    Meteor.loginVisitor(email);
  }
});

After write the email and submit the form, if I check the session variable in the console it is correct but if I check for Meteor.userId() it is always 'null', how I have to use it?