1 files changed, 43 insertions, 0 deletions
diff --git a/testing/web-platform/tests/dom/events/event-global-is-still-set-when-reporting-exception-onerror.html b/testing/web-platform/tests/dom/events/event-global-is-still-set-when-reporting-exception-onerror.html
new file mode 100644
index 0000000000..ceaac4fe2b
--- /dev/null
+++ b/testing/web-platform/tests/dom/events/event-global-is-still-set-when-reporting-exception-onerror.html
@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>window.onerror handler restores window.event after it reports an exception</title>
+<link rel="help" href="https://dom.spec.whatwg.org/#concept-event-listener-inner-invoke">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<body>
+<iframe src="resources/empty-document.html"></iframe>
+<iframe src="resources/empty-document.html"></iframe>
+
+<script>
+setup({ allow_uncaught_exception: true });
+
+async_test(t => {
+    window.onload = t.step_func_done(onLoadEvent => {
+        frames[0].onerror = new frames[1].Function(`
+            top.eventDuringSecondOnError = top.window.event;
+            top.frames[0].eventDuringSecondOnError = top.frames[0].event;
+            top.frames[1].eventDuringSecondOnError = top.frames[1].event;
+        `);
+
+        window.onerror = new frames[0].Function(`
+            top.eventDuringFirstOnError = top.window.event;
+            top.frames[0].eventDuringFirstOnError = top.frames[0].event;
+            top.frames[1].eventDuringFirstOnError = top.frames[1].event;
+
+            foo; // cause second onerror
+        `);
+
+        const myEvent = new ErrorEvent("error", { error: new Error("myError") });
+        window.dispatchEvent(myEvent);
+
+        assert_equals(top.eventDuringFirstOnError, onLoadEvent);
+        assert_equals(frames[0].eventDuringFirstOnError, myEvent);
+        assert_equals(frames[1].eventDuringFirstOnError, undefined);
+
+        assert_equals(top.eventDuringSecondOnError, onLoadEvent);
+        assert_equals(frames[0].eventDuringSecondOnError, myEvent);
+        assert_equals(frames[1].eventDuringSecondOnError.error.name, "ReferenceError");
+    });
+});
+</script>