[feature/auto-loading] Only check subdir if there is another name part.

PHPBB3-9682

phpBB/includes/class_loader.php

@@ -115,7 +115,7 @@ class phpbb_class_loader
 
 		$dirs = '';
 
-		for ($i = 0; is_dir($path_prefix . $dirs . $parts[$i]) && $i < sizeof($parts); $i++)
+		for ($i = 0, $n = sizeof($parts); $i < $n && is_dir($path_prefix . $dirs . $parts[$i]); $i++)
 		{
 			$dirs .= $parts[$i] . '/';
 		}

tests/class_loader/class_loader_test.php

@@ -23,6 +23,12 @@ class phpbb_class_loader_test extends PHPUnit_Framework_TestCase
 
 		$prefix .= 'includes/';
 
+		$this->assertEquals(
+			'',
+			$class_loader->resolve_path('phpbb_dir'),
+			'Class with same name as a directory is unloadable'
+		);
+
 		$this->assertEquals(
 			$prefix . 'class_name.php',
 			$class_loader->resolve_path('phpbb_class_name'),

tests/class_loader/includes/dir.php

@@ -0,0 +1,6 @@
+<?php
+
+class phpbb_dir
+{
+}
+