Bug 1794378 [wpt PR 36368] - history.state during a bfcache traversal…

…, a=testonly

Automatic update from web-platform-tests
history.state during a bfcache traversal

Per whatwg/html#6652, it must not get serialized and deserialized.
--

wpt-commits: 7d60342ce41a95f4db1e57dd324917a9bc8bf730
wpt-pr: 36368

testing/web-platform/tests/html/browsers/history/the-history-interface/history-state-after-bfcache.window.js

@@ -0,0 +1,43 @@
+// META: title=Navigating back to a bfcached page does not reset history.state
+// META: script=/common/dispatcher/dispatcher.js
+// META: script=/common/utils.js
+// META: script=/html/browsers/browsing-the-web/remote-context-helper/resources/remote-context-helper.js
+
+// See https:/whatwg/html/issues/6652.
+
+'use strict';
+
+promise_test(async t => {
+ const rcHelper = new RemoteContextHelper();
+
+ // Open a window with noopener so that BFCache will work.
+ const rc = await rcHelper.addWindow(null, { features: "noopener" });
+
+ // Add a pageshow listener to stash the event, and set history.state using replaceState().
+ await rc.executeScript(() => {
+ window.addEventListener('pageshow', (event) => {
+ window.pageshowEvent = event;
+ });
+
+ history.replaceState({ foo: 'bar' }, '', '');
+ window.stashedHistoryState = history.state;
+ });
+
+ const rc2 = await rc.navigateToNew();
+ await rc2.historyBack();
+
+ assert_implements_optional(
+ await rc.executeScript(() => window.pageshowEvent.persisted),
+ 'precondition: document was bfcached'
+ );
+
+ assert_equals(
+ await rc.executeScript(() => history.state.foo),
+ 'bar',
+ 'history.state was restored correctly'
+ );
+
+ assert_true(
+ await rc.executeScript(() => window.stashedHistoryState === history.state),
+ 'history.state did not get serialized and deserialized');
+});