function test_largo_fb_url_to_username()
{
/**
* A short list of valid Facebook IDs:
https://www.facebook.com/Foo-bar.1
https://www.facebook.com/profile.php?id=012345678901234&fref=ts
https://www.facebook.com/Foo-bar.2?rf=012345678901234
https://www.facebook.com/pages/Foo-bar.3/012345678901234
https://m.facebook.com/Foo-bar.4?_e_pi_=7%2CPAGE_ID10%2C0123456789
https://m.facebook.com/profile.php?id=012345678901234
https://m.facebook.com/?_rdr#!/Foo-bar.5?__user=012345678901234
*/
/**
* With no input, it should return an empty string
*/
$result = largo_fb_url_to_username("");
$this->assertEquals("", $result);
unset($result);
/**
* With a valid username, it should return that username
*/
$result = largo_fb_url_to_username("Foo-bar.0");
$this->assertEquals("Foo-bar.0", $result);
unset($result);
$result = largo_fb_url_to_username("012345678901234");
$this->assertEquals("012345678901234", $result);
unset($result);
/**
* With a valid URL, it should return the username
*/
$result = largo_fb_url_to_username("https://www.facebook.com/Foo-bar.1");
$this->assertEquals("Foo-bar.1", $result);
unset($result);
$result = largo_fb_url_to_username("https://www.facebook.com/profile.php?id=012345678901234&fref=ts");
$this->assertEquals("012345678901234", $result);
unset($result);
$result = largo_fb_url_to_username("https://www.facebook.com/Foo-bar.2?rf=012345678901234");
$this->assertEquals("Foo-bar.2", $result);
unset($result);
// For making a URL, Foo-bar.3 is a valid username, but so is the ID listed here.
$result = largo_fb_url_to_username("https://www.facebook.com/pages/Foo-bar.3/012345678901234");
$this->assertEquals("012345678901234", $result);
unset($result);
$result = largo_fb_url_to_username("https://m.facebook.com/Foo-bar.4?_e_pi_=7%2CPAGE_ID10%2C0123456789");
$this->assertEquals("Foo-bar.4", $result);
unset($result);
$result = largo_fb_url_to_username("https://m.facebook.com/profile.php?id=012345678901234");
$this->assertEquals("012345678901234", $result);
unset($result);
$result = largo_fb_url_to_username("https://m.facebook.com/?_rdr#!/Foo-bar.5?__user=012345678901234");
$this->assertEquals("Foo-bar.5", $result);
unset($result);
}
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>' . $fb_suspect . '</b> ' . __('does not allow followers on Facebook.') . '</p>' . '<p>' . __('<a href="https://www.facebook.com/help/201148673283205#How-can-I-let-people-follow-me?">Follow these instructions</a> to allow others to follow you.'));
}
}
}
}
<ul class="social-links">
<?php
if ($fb = $author_obj->fb) {
?>
<li class="facebook">
<a href="https://facebook.com/<?php
echo largo_fb_url_to_username(esc_url($fb));
?>
" title="<?php
echo esc_attr($author_obj->display_name);
?>
on Facebook" rel="me"><i class="icon-facebook"></i></a>
</li>
<?php
}
?>
<?php
if ($twitter = $author_obj->twitter) {
?>
<li class="twitter">
<a href="https://twitter.com/<?php
echo largo_twitter_url_to_username($twitter);
?>
"><i class="icon-twitter"></i></a>
</li>
<?php
}
?>
<?php