diff --git a/enrol/lti/tests/tool_provider_test.php b/enrol/lti/tests/tool_provider_test.php
index 64f3354efa3..5e673ec720f 100644
--- a/enrol/lti/tests/tool_provider_test.php
+++ b/enrol/lti/tests/tool_provider_test.php
@@ -75,7 +75,7 @@ class tool_provider_testcase extends advanced_testcase {
      */
     public function test_constructor_with_non_existent_tool() {
         $this->expectException('dml_exception');
-        new tool_provider(1);
+        new tool_provider(-1);
     }
 
     /**