URL: ensure deleting all params keeps ? in URL

diff --git a/url/urlsearchparams-delete.html b/url/urlsearchparams-delete.html
index fca6462..afc9c60 100644
--- a/url/urlsearchparams-delete.html
+++ b/url/urlsearchparams-delete.html
@@ -36,6 +36,14 @@
     params.delete('first');
     assert_false(params.has('first'), 'Search params object has no "first" name');
 }, 'Deleting appended multiple');
+
+test(function() {
+    var url = new URL('http://example.com/?param1&param2');
+    url.searchParams.delete('param1');
+    url.searchParams.delete('param2');
+    assert_equals(url.href, 'http://example.com/?', 'url.href has ?');
+    assert_equals(url.search, '', 'url.search does not have ?');
+}, 'Deleting all params keeps ? in URL');
 </script>
 </head>
 </html>