New is_windows_os testable implementation.

Author: dmitry-ivanov

src/classes/System/OS.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace Illuminated\Helpers\System;
+
+class OS
+{
+    public static function isWindows()
+    {
+        return (strtoupper(substr(php_uname(), 0, 7)) === 'WINDOWS');
+    }
+}

src/system.php

@@ -1,8 +1,10 @@
 <?php
 
+use Illuminated\Helpers\System\OS;
+
 if (!function_exists('is_windows_os')) {
     function is_windows_os()
     {
-        return (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN');
+        return OS::isWindows();
     }
 }