| <!DOCTYPE html> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <body> |
| <script> |
| promise_test(async () => { |
| assert_implements("HTMLPortalElement" in self); |
| var portal = document.createElement("portal"); |
| portal.src = "resources/portal-activate-inside-portal.html"; |
| let waitForMessage = new Promise((resolve, reject) => { |
| portal.onmessage = e => resolve(e.data); |
| document.body.appendChild(portal); |
| }); |
| var error = await waitForMessage; |
| assert_equals(error, "InvalidStateError"); |
| }, "activating a nested portal should throw an error"); |
| </script> |
| </body> |
