diff --git a/dom/nodes/attributes.js b/dom/nodes/attributes.js
index 096dd5fd7a37f3..ef32bf6a67732c 100644
--- a/dom/nodes/attributes.js
+++ b/dom/nodes/attributes.js
@@ -6,6 +6,7 @@ function attr_is(attr, v, ln, ns, p, n) {
   assert_equals(attr.namespaceURI, ns)
   assert_equals(attr.prefix, p)
   assert_equals(attr.name, n)
+  assert_equals(attr.nodeName, n);
   assert_equals(attr.specified, true)
 }