IHF: Illuminate dependency removed.

Author: dmitry-ivanov

src/str.php

@@ -1,17 +1,15 @@
 <?php
 
-use Illuminate\Support\Str;
-
 if (!function_exists('str_lower')) {
     function str_lower($string)
     {
-        return Str::lower($string);
+        return mb_strtolower($string, 'UTF-8');
     }
 }
 
 if (!function_exists('str_upper')) {
     function str_upper($string)
     {
-        return Str::upper($string);
+        return mb_strtoupper($string, 'UTF-8');
     }
 }