1 files changed, 29 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/document-write/module-delayed.html b/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/document-write/module-delayed.html
new file mode 100644
index 0000000000..acdeab59ff
--- /dev/null
+++ b/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/document-write/module-delayed.html
@@ -0,0 +1,29 @@
+<!doctype html>
+<title>async document.write in a module</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="log"></div>
+<script>
+async_test(t => {
+  // Expose {test} in the iframe for using the step_timeout helper.
+  document.test = t;
+  const iframe = document.createElement("iframe");
+
+  iframe.onerror = t.unreached_func("Error loading iframe");
+
+  let onLoadWasCalled = false;
+  iframe.onload = t.step_func(() => {
+    onLoadWasCalled = true;
+    assert_equals(iframe.contentDocument.body.textContent, "Initial body contents\n");
+    // Don't call the event handler another time after document.write.
+    iframe.onload = null;
+  });
+  document.addEventListener("documentWriteDone", t.step_func_done(() => {
+    assert_true(onLoadWasCalled, "onload must be called");
+    assert_equals(iframe.contentDocument.body.textContent, "document.write body contents\n");
+  }));
+
+  iframe.src = "module-delayed-iframe.html";
+  document.body.appendChild(iframe);
+});
+</script>