diff --git a/modules/libjar/test/unit/test_jarchannel.js b/modules/libjar/test/unit/test_jarchannel.js
index 530ac65f453..49421b14c2b 100644
--- a/modules/libjar/test/unit/test_jarchannel.js
+++ b/modules/libjar/test/unit/test_jarchannel.js
@@ -310,4 +310,6 @@ if (inChild) {
     });
 } // if inChild
 
-function run_test() run_next_test();
+function run_test() {
+  return run_next_test();
+}