I am using Elgg 1.12.4 and profile manager 9.1. 

In the profile manager plugin settings there is an option titled "Generate username from email", it is working correctly only when the username grabbed from the email does not exists in the users_entity or the user being looked up has been validated already. 

if user one comes with email address abcd@email.com and registers, his username will be abcd. If a second user comes with email address abcd@@xyz.com, although the email username are the same the following code makes the username unique but only when abcd@email.com user has been validated. 

profile_manager/libs/hooks.php

// generate username
    $username = get_input('username');
    $email = get_input('email');
    if (empty($username) && !empty($email) && (elgg_get_plugin_setting("generate_username_from_email", "profile_manager") == "yes")) {
        
        $email_parts = explode('@', $email);
        $base_username = $email_parts[0];
        $tmp_username = $base_username;
        
        $i = 1;
        while (get_user_by_username($tmp_username)) {
            $tmp_username = $base_username . $i;
            $i++;
        }
                
        set_input('username', $tmp_username);
    }
}

Function get_user_by_username seems to be able to read only when the username has been already validated. 

Line 241 in http://reference.elgg.org/users_8php_source.html

Should I create my own SQL and remove the access part or there is another built function that I can use?