Remove include or require declaration from all helpers test
diff --git a/tests/codeigniter/helpers/string_helper_test.php b/tests/codeigniter/helpers/string_helper_test.php
index a884d62..29c3d65 100644
--- a/tests/codeigniter/helpers/string_helper_test.php
+++ b/tests/codeigniter/helpers/string_helper_test.php
@@ -1,9 +1,12 @@
 <?php
 
-require_once(BASEPATH.'helpers/string_helper.php');
+class String_helper_test extends CI_TestCase {
 
-class String_helper_test extends CI_TestCase
-{
+	public function set_up()
+	{
+		$this->helper('string');
+	}
+
 	public function test_strip_slashes()
 	{
 		$expected = array(