| async_test(t => { |
| const frame = document.body.appendChild(document.createElement("iframe")); |
| t.add_cleanup(() => { frame.remove(); }); |
| const originalHTMLElement = frame.contentDocument.documentElement; |
| assert_equals(originalHTMLElement.localName, "html"); |
| const observer = new frame.contentWindow.MutationObserver(t.step_func_done(records => { |
| // Even though we passed `subtree: true` to observer.observe, due to the |
| // fact that "replace all" algorithm removes children with the "suppress |
| // observers flag" set, we still only get the html element as the sole |
| // removed node. |
| assert_equals(records.length, 1); |
| assert_equals(records[0].type, "childList"); |
| assert_equals(records[0].target, frame.contentDocument); |
| assert_array_equals(records[0].addedNodes, []); |
| assert_array_equals(records[0].removedNodes, [originalHTMLElement]); |
| })); |
| observer.observe(frame.contentDocument, { childList: true, subtree: true }); |
| assert_equals(frame.contentDocument.open(), frame.contentDocument); |
| }, "document.open() should inform mutation observer of node removal"); |