Make Laravel slug support utf8 characters

If you ever wanted to use Laravel Str:slug() method, you might notice it only supports Latin characters. By looking at Str class \vendor\laravel\framework\src\Illuminate\Support\Str.php you see:

public static function slug($title, $separator = '-')
{
  $title = static::ascii($title);

  // Convert all dashes/underscores into separators
  $flip = $separator == '-' ? '_' : '-';
  $title = preg_replace('!['.preg_quote($flip).']+!u', $separator, $title);

  // Remove all characters that are not the separator, letters, numbers, or whitespace.
  $title = preg_replace('![^'.preg_quote($separator).'\pL\pN\s]+!u', '', mb_strtolower($title));

  // Replace all separator characters and whitespace by a single separator
  $title = preg_replace('!['.preg_quote($separator).'\s]+!u', $separator, $title);

  return trim($title, $separator);
}

At the very first line, the string is converted to ANSI. That's why you cannot use UTF-8 characters on return. You can comment the line out and see the result. But editing the Laravel source is not the best solution

To change the slug method functionality, it's best to extend or override this method. For doing so, first create a file named app/macros.php, then copy/paste the main slug method into this file and convert it to a closure method:

Str::macro('slug_utf8', function($title, $separator = '-')
{
    //$title = static::ascii($title); //comment it out to suport farsi

    // Convert all dashes/underscores into separators
    $flip = $separator == '-' ? '_' : '-';

    $title = preg_replace('!['.preg_quote($flip).']+!u', $separator, $title);

    // Remove all characters that are not the separator, letters, numbers, or whitespace.
    $title = preg_replace('![^'.preg_quote($separator).'\pL\pN\s]+!u', '', mb_strtolower($title));

    // Replace all separator characters and whitespace by a single separator
    $title = preg_replace('!['.preg_quote($separator).'\s]+!u', $separator, $title);

    return trim($title, $separator);
});

Before this method is used in your application, you should add this macro.php file to the app/start/global.php, open this file and at the end of the file, add this line of code:

require app_path().'/macros.php';

Now you have a new slug_utf8 method that can be used in your applications:

$slug = Str::slug_utf8($value);