1 files changed, 34 insertions, 0 deletions
diff --git a/testing/web-platform/tests/navigation-api/navigate-event/navigate-destination-dynamic-index.html b/testing/web-platform/tests/navigation-api/navigate-event/navigate-destination-dynamic-index.html
new file mode 100644
index 0000000000..2e0f1ea497
--- /dev/null
+++ b/testing/web-platform/tests/navigation-api/navigate-event/navigate-destination-dynamic-index.html
@@ -0,0 +1,34 @@
+<!doctype html>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../navigation-methods/return-value/resources/helpers.js"></script>
+<script>
+promise_test(async t => {
+  // Wait for after the load event so that the navigation doesn't get converted
+  // into a replace navigation.
+  await new Promise(resolve => window.onload = () => t.step_timeout(resolve, 0));
+  await navigation.navigate("#1").finished;
+
+  let back_destination;
+  navigation.addEventListener("navigate", t.step_func(e => {
+    back_destination = e.destination;
+    assert_equals(back_destination.index, 0);
+  }), { once: true });
+  await navigation.back().finished;
+
+  // Disposing the destination entry of back_destination should update
+  // back_destination.index, even though back_destination's navigation has
+  // completed.
+  await navigation.navigate("#clobber_back", { history: "replace" }).finished;
+  assert_equals(back_destination.index, -1);
+
+  navigation.addEventListener("navigate", t.step_func(e => {
+    assert_equals(e.destination.index, 1);
+
+    // Dispose the destination entry and destination.index should update.
+    navigation.navigate("#clobber_forward");
+    assert_equals(e.destination.index, -1);
+  }), { once: true });
+  await assertBothRejectDOM(t, navigation.forward(), "AbortError");
+}, "navigate event destination.index should be dynamic");
+</script>