diff --git a/enrol/lti/tests/helper_test.php b/enrol/lti/tests/helper_test.php
index c6c40f77056..b88b20ea4e1 100644
--- a/enrol/lti/tests/helper_test.php
+++ b/enrol/lti/tests/helper_test.php
@@ -433,7 +433,6 @@ class enrol_lti_helper_testcase extends advanced_testcase {
 
     /**
      * Test set_xpath when an incorrect xpath expression is given.
-     * @expectedException coding_exception
      */
     public function test_set_xpath_incorrect_xpath() {
         $parameters = [
@@ -451,10 +450,9 @@ class enrol_lti_helper_testcase extends advanced_testcase {
         $document = new \DOMDocument();
         $document->load(realpath(__DIR__ . '/fixtures/input.xml'));
         $xpath = new \DOMXpath($document);
+
+        $this->setExpectedException("coding_exception");
         $function->invokeArgs(null, [$xpath, $parameters]);
-        $result = $document->saveXML();
-        $expected = file_get_contents(realpath(__DIR__ . '/fixtures/' . $expected));
-        $this->assertEquals($expected, $result);
     }
 
     /**