Documentation for "ensureAuthentication" "isAuthenticated" passport's functions?

While not explicitly documented anywhere easily found, you can see where the the isAuthenticated and isUnauthenticated flags are set in the Passport code at https://github.com/jaredhanson/passport/blob/a892b9dc54dce34b7170ad5d73d8ccfba87f4fcf/lib/passport/http/request.js#L74.

ensureAuthenticated is not official, but can be implemented via the following:

function ensureAuthenticated(req, res, next) {
  if (req.isAuthenticated())
    return next();
  else
    // Return error content: res.jsonp(...) or redirect: res.redirect('/login')
}

app.get('/account', ensureAuthenticated, function(req, res) {
  // Do something with user via req.user
});