diff --git a/tests/functions/is_absolute_test.php b/tests/functions/is_absolute_test.php
new file mode 100644
index 0000000000..26425d2a36
--- /dev/null
+++ b/tests/functions/is_absolute_test.php
@@ -0,0 +1,34 @@
+<?php
+/**
+*
+* @package testing
+* @copyright (c) 2013 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+require_once dirname(__FILE__) . '/../../phpBB/includes/functions.php';
+
+class phpbb_functions_is_absolute_test extends phpbb_test_case
+{
+	static public function is_absolute_data()
+	{
+		return array(
+			array('/etc/phpbb', true),
+			array('etc/phpbb', false),
+
+			// Until we got DIRECTORY_SEPARATOR replaced in that function,
+			// test results vary on OS.
+			array('c:\windows', DIRECTORY_SEPARATOR == '\\'),
+			array('C:\Windows', DIRECTORY_SEPARATOR == '\\'),
+		);
+	}
+
+	/**
+	* @dataProvider is_absolute_data
+	*/
+	public function test_is_absolute($path, $expected)
+	{
+		$this->assertEquals($expected, is_absolute($path));
+	}
+}