Add a test for scoped custom element registry API changes to unbreak Polymer's polyfill

rniwa · web-flow · commit f08d4a359b2b · 2025-02-28T08:07:20.000+01:00
diff --git a/custom-elements/revamped-scoped-registry/ShadowRoot-init-customElements.tentative.html b/custom-elements/revamped-scoped-registry/ShadowRoot-init-customElements.tentative.html
@@ -35,8 +35,8 @@
 
 test(() => {
     const host = document.body.appendChild(document.createElement('div'));
-    assert_throws_js(TypeError, () => host.attachShadow({mode: 'closed', customElements: null}));
-}, 'attachShadow() should throw for a null customElements value');
+    host.attachShadow({mode: 'closed', customElements: null});
+}, 'attachShadow() should not throw for a null customElements value');
 
 </script>
 </body>
diff --git a/custom-elements/revamped-scoped-registry/polymer-polyfill-regression.tentative.html b/custom-elements/revamped-scoped-registry/polymer-polyfill-regression.tentative.html
@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html>
+<head>
+<meta name="author" title="Ryosuke Niwa" href="mailto:rniwa@webkit.org">
+<link rel="help" href="https://github.com/whatwg/html/issues/10854">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+</head>
+<body>
+<script>
+
+test(() => {
+    document.createElement('div').attachShadow({mode: 'closed', customElements: { }});
+}, 'attachShadow should not throw an exception when an arbitrary type is passed to customElements');
+
+test(() => {
+    document.createElement('div').attachShadow({mode: 'closed'}).customElements = { };
+}, 'The setter of customElements IDL attribute should not throw an exception when assigned of an arbitrary type');
+
+</script>
+</body>
+</html>
