diff --git a/test/unit/core-util.test.js b/test/unit/core-util.test.js
index 68cf980bb..0ebbf7bbd 100644
--- a/test/unit/core-util.test.js
+++ b/test/unit/core-util.test.js
@@ -20,7 +20,7 @@ describe('core/util', () => {
     });
 
     test('non external local url with three ///', () => {
-      const result = isExternal(`//${location.host}/docsify/demo.md`);
+      const result = isExternal(`///${location.host}/docsify/demo.md`);
 
       expect(result).toBeFalsy();
     });