function validate_fb_username($errors, $update, $user)
{
if (isset($_POST["fb"])) {
$fb_suspect = trim($_POST["fb"]);
if (!empty($fb_suspect)) {
$fb_user = largo_fb_url_to_username($fb_suspect);
if (preg_match('/[^a-zA-Z0-9\\.\\-]/', $fb_user)) {
// it's not a valid Facebook username, because it uses an invalid character
$errors->add('fb_username', '<b>' . $fb_suspect . '</b> ' . __('is an invalid Facebook username.') . '</p>' . '<p>' . __('Facebook usernames only use the uppercase and lowercase alphabet letters (a-z A-Z), the Arabic numbers (0-9), periods (.) and dashes (-)'));
}
if (!largo_fb_user_is_followable($fb_user)) {
$errors->add('fb_username', ' <b>' . $fb_suspect . '</b> ' . __('does not allow followers on Facebook.') . '</p>' . '<p>' . __('<a href="https://www.facebook.com/help/201148673283205#How-can-I-let-people-follow-me?">Follow these instructions</a> to allow others to follow you.'));
}
}
}
}
function test_largo_fb_user_is_followable()
{
/**
* With no input, there should be no <table> in the resulting iframe
*/
$result = largo_fb_user_is_followable("");
$this->assertFalse($result, "The Facebook follow button iframe HTML structure has changed and largo_fb_url_to_username no longer operates predictably. Please fix.");
unset($result);
/**
* With Mark Zuckerberg, we hope that he will remain followable.
*/
$result = largo_fb_user_is_followable("zuck");
$this->assertTrue($result, "Either Mark Zuckerberg is no longer followable, or the Facebook follow button iframe HTML structure has changed and largo_fb_url_to_username no longer operates predictably. Please log into Facebook and check that https://www.facebook.com/zuck has a 'Follow' button.");
unset($result);
/**
* With a user that does not exist, we hope that the user will continue to not exist
*/
$result = largo_fb_user_is_followable("abcdefghijklmnopqrstuvwxyz12");
$this->assertFalse($result, "Either https://www.facebook.com/abcdefghijklmnopqrstuvwxyz12 is user that exists and allows follows, or the Facebook follow button iframe HTML structure has changed and largo_fb_url_to_username no longer operates predictably.");
unset($result);
/**
* With an invalid username, this should return false
*/
$result = largo_fb_user_is_followable("%22Aardvarks+lurk%2C+OK%3F%22");
$this->assertFalse($result, "Either https://www.facebook.com/%22Aardvarks+lurk%2C+OK%3F%22 is user that exists and allows follows (not at all likely), or the Facebook follow button iframe HTML structure has changed and largo_fb_url_to_username no longer operates predictably.");
unset($result);
}
