fixed karma

app/assets/javascripts/lib/utils/url_utility.js

@@ -85,9 +85,9 @@ export function redirectTo(url) {
 }
 
 export function webIDEUrl(route = undefined) {
-  let returnUrl = `${gon.relative_url_root}/-/ide/`;
+  let returnUrl = `${gon.relative_url_root || ''}/-/ide/`;
   if (route) {
-    returnUrl += `project${route.replace(new RegExp(`^${gon.relative_url_root}`), '')}`;
+    returnUrl += `project${route.replace(new RegExp(`^${gon.relative_url_root || ''}`), '')}`;
   }
   return returnUrl;
 }

spec/javascripts/lib/utils/url_utility_spec.js

@@ -2,6 +2,10 @@ import { webIDEUrl } from '~/lib/utils/url_utility';
 
 describe('URL utility', () => {
   describe('webIDEUrl', () => {
+    afterEach(() => {
+      gon.relative_url_root = '';
+    });
+
     describe('without relative_url_root', () => {
       it('returns IDE path with route', () => {
         expect(webIDEUrl('/gitlab-org/gitlab-ce/merge_requests/1')).toBe(