diff --git a/app/assets/javascripts/ide/stores/modules/file_templates/actions.js b/app/assets/javascripts/ide/stores/modules/file_templates/actions.js
index c86310be3794d85e273ad05d2760857627183635..43237a294663bce690cf7f2c219c1f4ca62d6ee2 100644
--- a/app/assets/javascripts/ide/stores/modules/file_templates/actions.js
+++ b/app/assets/javascripts/ide/stores/modules/file_templates/actions.js
@@ -78,4 +78,5 @@ export const undoFileTemplate = ({ dispatch, commit, rootGetters }) => {
   commit(types.SET_UPDATE_SUCCESS, false);
 };
 
+// prevent babel-plugin-rewire from generating an invalid default during karma tests
 export default () => {};